第三十六卷第二期 (期別140) (110年)

第三十六卷第二期 (期別140) (110年)

標題長跨桁架圍束式挫屈束制支撐之研究
作者陳雋、林昱成、吳安傑、陳律安、蔡克銓
關鍵字挫屈束制支撐、巨型斜撐、桁架圍束單元、撓曲剛度、剪力剛度、 穩定性分析
摘要跨越多樓層之挫屈束制支撐在高層建築結構中的抗震應用漸趨廣泛,桁架圍束式挫屈束制支撐(truss-confined buckling-restrained brace, TC-BRB) 為較新型之 BRB,TC-BRB 於圍束鋼管外部再配置一桁架圍束系統,由任意數量、方向與尺寸之桁架構架所構成,並與圍束鋼管共組成圍束單元來提供所需之撓曲剛度;因此其圍束鋼管與內灌水泥砂漿的撓曲剛度與斷面需求得以大幅下降。當安裝為具長跨與高軸力容量之斜撐構件時,更得以發揮減少材料用量、自重及初始凹曲等優點。本研究提出一全新型 TC-BRB,將桁架圍束系統之斷面高度由過去的等斷面改為沿 BRB 軸向變化,於跨中央最高並以正弦函數曲線向兩端漸縮,更有效率地使用材料並獲更優美之外觀。為使此新創型 BRB 方便實際工程應用,本研究建立穩定性理論模型與耐震設計方法並進行相關實驗與數值驗證。先提出桁架圍束系統等效撓曲剛度與剪力剛度計算方式,再建立穩定性理論模型。考量剪力效應計算 TC-BRB 之整體彈性撓曲挫屈強度(Pcr);並再考量初始缺陷與材料非線性行為來計算整體挫屈破壞強度(Plim)。本研究並藉 ABAQUS 有限元素模型分析進行數值驗證,結果顯示理論模型在圍束單元的 Pcr 計算上,誤差小於 10%;而於整體 TC-BRB 的 Pcr 計算上,誤差更小於 3%。為驗證理論並評估 TC-BRB 之實際遲滯消能行為,本研究第一階段設計並新造兩組具不同桁架圍束系統型態、1/5 縮尺總長 6.3 米、100 噸級之 TC-BRB 試體,利用國家地震工程研究中心多軸向試驗系統執行反覆加載試驗。理論模型考量殘餘應力的效應後,預測所得 Plim 與試驗結果的誤差小於 6%;實驗證實本研究所建理論模型於穩定性預測之準確性,更證實本研究所提之設計方法與檢核程序的可靠性。為觀察 TC-BRB 更嚴峻的耐震消能與穩定性表現,本研究第二階段再設計兩組 TC-BRB 試體並提高其整體穩定性容量,理論預測的 Plim 與試驗所得結果兩者誤差小於 7%,再次確認所提理論模型之準確性;本文提供 TC-BRB 之耐震設計流程與範例以供參考。
TitleLong-Span Buckling-Restrained Braces using Truss-Confined Restrainers
AuthorChun Chen, Yu-Cheng Lin, An-Chien Wu, Lu-An Chen, Keh-Chyuan Tsai
Keywordsbuckling-restrained brace, mega brace, truss-confined restrainer, flexural rigidity, shear rigidity, stability analysis
AbstractLong span buckling-restrained braces (BRBs) are getting popular for applications in seismic tall buildings. Recently, a novel type of BRB, namely the truss-confined BRB (TC-BRB) with a constant-depth truss built into the restrainerhas been investigated. The TC-BRB’s restrainer is constructed by attaching an additional truss system composed of several steel open-web truss frames outside the central steel casing in order to develop the overall restraining rigidity. Thus, the cross-sectionof the central steel casing and the weight of the infilled mortar in the TC-BRB can be significantly reduced in comparison with the conventional BRBs. The initial crookedness caused by the BRBs’ self-weight can also be reduced in the cases of long-span and large axial capacity BRB designs. This study investigates a new type of TC-BRB using a varying-depth truss system in the restrainers. This type of TC-BRB could save construction material and achieve the structural aesthetic more effectively than those using the constant-depth trusses. In this study, stability analytical model and seismic design procedures are developed and verified. Key mechanical properties including equivalent flexural rigidity and shear rigidity of the truss system are firstly presented. It is illustrated that the TC-BRBs’ elastic flexural buckling strength (Pcr) can be satisfactorily computed by incorporating Timoshenko shear effect into the classical stability theory. TC-BRBs’s buckling failure strength (Plim) can be further computed by considering the initial imperfections and inelastic material property.Abaqus finite element model (FEM) analysis results indicate that the proposed analytical model can satisfactorily predict the restrainers’ Pcr with errors less than 10%; and predict the TC-BRBs’ Pcr with errors less than 3%. In the first phase experiment, two 1/5-scale TC-BRB specimens, each of 6.3m long with the 1016-kN nominal yield strength anda constant- or varying-depth truss design, were tested in NCREE. Cyclic test results confirm that the Plim of the two TC-BRB specimens can be accurately predicted using the proposed analytical model with errors less than 6% when the effects of residual stresses in the truss members are considered. In the second phase experiment, two additional specimens were fabricated with significantly increased stability capacities. Cyclic test results show that the Plim of these two specimens can also be accurately predicted with the errors less than 7%, further confirm the reliability of the proposed analytical model. The TC-BRBs’ experimental performance also suggests that the proposed design procedures are generally conservative and practical. This study concludes with the recommendations, produres and examples on the seismic design of the proposed TC-BRBs using the constant- or varying-depth trussses.
標題非定值軸力作用下含組合繫筋 RC 柱之耐震性能
作者李台光、陳正誠
關鍵字組合繫筋、搭接長度、軸拉力、RC柱、耐震性能
摘要組合繫筋為由兩支一端為180度彎鉤另一端為直線的J形鋼筋搭接組合而成。本研究完成4座大尺寸鋼筋混凝土柱試體之反復側向載重試驗,探討非定值軸力作用下含組合繫筋RC柱之耐震性能。研究結果顯示:(1)非定值軸力作用下,使用180度彎鉤一體繫筋(兩端使用180度彎鉤之一體繫筋)之試體承受軸壓力之韌性(塑性轉角)表現最佳,使用組合繫筋之試體次之,使用傳統繫筋(一端具有135度彎鉤,而另一端為90度彎鉤之繫筋)之試體韌性表 現最差;(2)不論使用組合繫筋、180度彎鉤一體繫筋或傳統繫筋之RC柱試體,承受軸拉力之韌性表現優於承受軸壓力之韌性表現;(3)僅承受軸壓力之柱,當柱軸力比小於30%時,可採用組合繫筋取代傳統繫筋;(4)建築結構內柱承受較大之軸壓力,當柱在地震過程中僅承受軸壓力,且柱軸力比大於30%時,此時使用組合繫筋不但可以合乎規範要求且施工容易;(5)當柱在地震過程中承受反復軸力(即軸壓力及軸拉力)時,一般而言此種情形之 柱軸力比小於30%,此時可以採用組合繫筋取代傳統繫筋。
TitleThe seismic performance of reinforced concrete columns using the lap-spliced crosstie with various axial load
AuthorTai-Kuang Lee, Cheng-Cheng Chen
Keywordslap-spliced crosstie, lap splice length, axial tension, RC columns, seismic performance
AbstractA lap-spliced crosstie consists of two J-shaped steel bars (rebars) that have a straight end and an end featuring a 180° hook. In this study, the cyclic lateral load test of four large-scale reinforced concrete columns with axial force proportional to the lateral force was conducted to discuss the seismic performance of RC columns with lap-spliced crossties and investigate the axial tension load effect. The research results are presented as follows: (a) The seismic performance of the specimens that adopted lap-spliced crossties is superior to that of the specimen using conventional crossties and worse than that of the specimen using crossties featuring a 180° hook on the two ends. (b) The ductility of RC columns comprising lap-spliced crossties, crossties featuring a 180° hook on the two ends and conventional crossties under axial tension is superior to that under axial compression. (c) For RC columns under axial compression, when the axial force ratio is less than 30%, lap-spliced crossties can be used instead of conventional crossties. (d) The inner columns of the building structure are subjected to large axial compression. When the columns are only subjected to axial compression during the earthquake, and the column axial force ratio is greater than 30%, the use of lap-spliced crossties can not only meet the ACI design requirements, but also facilitate the construction. (e) When the columns are subjected to repeated axial forces (axial compression and axial tension) during the earthquake, generally speaking, the column axial force ratio in this case is less than 30%. In this case, lap-spliced crossties can be used to replace conventional crossties.
標題自來水配水池結構耐震評估之載重需求
作者翁元滔、劉季宇、沈文成、林敏郎、李昭賢、鍾立來
關鍵字自來水設施、耐震評估、配水池
摘要進行池狀結構之耐震評估與分析程序時,須先估算其所須考慮的靜載重、活載重、土壤載重、流體載重、溫度載重及地震載重,其中地震載重又可分成地震引致流體動態載重、土壤動態載重及構體本身之地震力等,而地震引致流體之動態載重又可分成流體衝擊模態載重、流體對流模態載重、流體垂直振動引致之水平動態載重等;其次,地震引致土壤之動態載重又可分成土壤主、被動土壓力等;另外,池狀結構構體本身亦應考慮其垂直地震力及池牆本身之側向慣性力。本研究針對國內常見的池狀結構的載重需求估算方式與耐震評估流程進行研討,俾使其耐震評估與分析程序更加完備。
TitleLoad demand assessment of liquid storage tank in water supply facilities
AuthorYuan-Tao Weng, Gee-Yu Liu, Wen-Cheng Shen, Min-Lang Lin, Lap-Loi Chung, Chao- Hsien Li
Keywordswater supply facilities, seismic evaluation, liquid storage tank
AbstractWhen carrying out the seismic evaluation and analysis procedure of the liquid storage tank, the static load, live load, soil load, fluid load, temperature load and seismic load must be estimated first. The seismic load can be divided into earthquake-induced fluid dynamic load, dynamic load of the soil and the seismic force induced by the self-weight of the structure. Firstly, the dynamic load of the fluid caused by the earthquake can be further divided into the fluid impulsive modal load, the fluid convective modal load, and the horizontal dynamic load caused by the vertical vibration of the fluid. Secondly, the soil dynamic load caused earthquakes can also be divided into active soil pressure and passive soil pressure. In addition, the vertical seismic force of the liquid storage tank and the lateral inertial force of the tank wall should also be considered. This study focuses on load demand assessment methods and seismic evaluation process for the common pool-like water tank structure in Taiwan to make the seismic evaluation and analysis procedures more feasible and reasonable.
標題跨斷層橋梁之地震反應研究
作者洪曉慧、何蓮桂、何宜哲、莊清鏘、黃仲偉
關鍵字跨斷層橋梁、非線性動力歷時、多支承輸入、地表位移輸入
摘要目前橋梁耐震規範主要是透過放大係數來考慮近斷層效應,對於跨斷層 橋梁並無相關的規定。然而跨斷層橋梁在斷層線兩側由於會因地表相對錯動而導致不同的變形趨勢,因此在數值模擬上必須採用多支承非同步輸入,計算橋梁模型在地震作用下的結構地震反應。本研究之目的在建立以地表位移輸入法為基礎之多支承地震輸入方式,用以探討跨斷層橋梁受地震作用之反應。首先以近斷層地震的地表加速度歷時經數值積分得到對應的地表位移歷時,利用多支承位移輸入方式進行非線性動力歷時分析來模擬跨斷層橋梁的地震反應。並進一步比較地表位移分配方式、斷層穿越角度、橋面板支承形式等對於跨斷層橋梁受震反應之影響。數值模擬結果顯示非同步輸入地震歷時會使橋梁結構產生局部較大變形與內力;同步輸入地震歷時則會使橋梁結構產生較大的絕對加速度。此外,本文就位移的分配方式區分為絕對錯位和相對錯位兩種,數值結果顯示在內力計算的部分,相對錯位與絕對錯位所得之最大值差異不大;但變形的部分,絕對錯位所得之最大值往往高於相對錯位所得之最大值。模擬同時顯示斷層水平角45度的作用下,對於柱底扭矩會產生較明顯的放大,但其餘物理量會小於斷層水平角90度的作用。最後,本文依主梁與柱頂接合處不同的邊界條件,將橋型分為連續橋、簡支梁橋和構架橋等三種。構架橋與連續橋的最大歷時反應相當接近,簡支梁橋各項物理量的最大歷時反應相較於連續橋可能增大或減少。
TitleSeismic Performance of Crossing–fault Bridges
AuthorHsiao-Hui Hung, Lian-Gui He, Yi-Che Ho, Ching-Chiang Chuang, Chang-Wei Huang
KeywordsCrossing-fault bridge, nonlinear time history, multiple excitation, ground displacement input
AbstractThe influences of near-fault earthquakes are taken into account only by the magnification factors in the seismic design code for highway bridges. There are no related specifications about crossing-fault bridges in the design code. However, cross-fault bridges which are subjected to different ground motions at opposite sides of the fault line suffer more attacks in earthquakes. In this study, the seismic responses of cross-fault bridges are simulated with the multiple-excitation method and solved by nonlinear dynamic time history analyses. The displacement time history of each excitation is obtained by integrating the acceleration time history of a near-fault ground motion. The influences of the velocity impulse and residual displacements of near-fault earthquakes on the seismic responses of cross-fault bridges are discussed. In addition, the effects of the boundary conditions of the bridge deck and the angle between the bridge and fault line on the seismic responses of cross-fault bridges are also elaborated here. Numerical results demonstrate that the multiple-excitation simulation obtained larger local deformation and internal forces. On the other hand, the single-excitation simulation obtained larger absolute acceleration. Moreover, the ground displacements from integration are further divided into absolute displacements and relative displacements, which are assigned to the ground motions at opposite sides of the fault line. Numerical results show that there are no obvious differences on internal forces between these two displacement distributions. However, the absolute displacement generates larger member deformation. Moreover, the torsions at the bottom of bridge columns are magnified when the fault angle is 45°. Finally, the influences of different boundary conditions between bridge slabs and columns on the seismic responses are investigated. The seismic responses of rigid connections are similar to those of pin connections while the seismic responses of simply supported bridges have different characteristics
標題不規則橋梁機率式耐震與倒塌風險評估之研究
作者劉光晏、呂依涵
關鍵字橋梁、勁度不規則、基樁裸露、土壤彈簧、機率式倒塌評估
摘要本研究探討既有群樁基礎橋梁,因沖刷導致基礎裸露前、後之耐震性能及倒塌機率。首先,針對土壤結構互制行為進行實驗與分析比較。根據群樁基礎單柱結構之雙軸向大型振動台實驗結果,比較美國石油協會(API )、日本道路橋示方書(JRA)及本研究之等值線性土壤彈簧法。研究結果顯示,在綜合考量時間成本與結果準確度下,API土壤彈簧法是較佳之樁土互制模擬方式。爰此,將API土壤彈簧應用至一座四跨全橋模型,採用增量動力分析法(IDA)並參考FEMA P58流程,探討不同橋基裸露程度之破壞模式、構件轉角韌性容量與不同等級地震之耐震能力與破壞機率,最後再與公路橋梁耐震評估與補強設計規範草案(2018年版)之靜力側推分析法進行比較。案例分析顯示,FEMA P58要求等級III地震作用下倒塌機率小於 10%,對於橋梁結構過於嚴格。短柱位置之樁基礎發生裸露時,對整體耐震性能有明顯降低。採用側推分析進行勁度不規則橋梁之耐震能力評估時, 其結構反應較動力分析有不保守的疑慮。
TitleProbabilistic Assessment of Seismic Performance and Collapse Risk for Irregularly Bridge
AuthorKuang-Yen Liu, Yi-Han Lu
KeywordsScouring Effect, Soil Spring, Group Pile Effect, Probabilistic Assessment Method, Collapse Risk Analysis, Incremental Dynamic Analysis, Static Pushover Analysis
AbstractThis study investigates the seismic performance and collapse risk of a group pile foundation irregularly bridge after scouring, which use API soil spring method to build a group pile foundation, four-span bridge models, and use probabilistic assessment to discuss the seismic performance due to different scouring places. This methodology was presented by previous researcher. For numerical analysis, this study uses SAP2000 to do incremental dynamic analysis (IDA). Afterward, based on the result, also establish fragility curve considering IO, LS, and CP performance. This study also uses pushover analysis to evaluate the seismic performance of bridge after scouring. The result shows the first yielding point for group pile will appear at the top of the pile. Second, Seismic performance for the bridge will have the greatest influence when scouring was taken place at the pier which has the biggest stiffness difference compare to its nearby pier. Last, pushover analysis for irregularly bridge may underestimate its reaction compare to nonlinear time history analysis. All in all, this simplified probabilistic procedure can be used as a reference for future seismic performance evaluation for bridges.

第三十六卷第一期 (期別139) (110年)

第三十六卷第一期(期別139)(110年)

第十五屆結構工程暨第五屆地震工程研討會特刊(下集)

客座主編:周中哲、廖文義、洪崇展

標題低矮型 RC 建築物之震後耐震性能評估方法研究
作者邱建國、宋欣芳、邱聰智
關鍵字殘餘耐震性能、損傷等級、折減因子
摘要為量化鋼筋混凝土(RC)柱構件的震後殘餘耐震性能,本文採用先前靜力、動力加載以及「太平洋地震工程研究中心結構性能數據庫(PEER)」所得的柱構件試驗研究結果所獲得之強度、勁度和能量消散的折減因子,並應用非線性鉸修正方法,提出針對震損低矮型RC建築物殘餘耐震性能的初步與詳細評估方法。另在案例研究中選擇一棟實際的震損建築物,以展示震後受損RC建築物的殘餘耐震性能評估方法的應用。
TitleStudy on a Post-earthquake Seismic Performance Evaluation Method for Low-rise RC buildings
AuthorChien-Kuo Chiu, Hsin-Fang Sung, Tsung-Chih Chiou
Keywordsresidual seismic capacity, damage level, reduction factor.
AbstractTo quantify the post-earthquake residual seismic capacity of reinforced concrete (RC) column members, the static-cyclic loading and dynamic loading experimental results obtained in previous work, and the “Pacific Earthquake Engineering Research Center Structural Performance Database (PEER)” are used to obtain reduction factors of strength, stiffness and energy dissipation. This work also applies the method of the modified nonlinear hinge and proposes the preliminary and detailed seismic performance assessment method for the residual seismic performance of earthquake-damaged RC buildings. In the case study, this work selects one actual earthquake-damaged building to display the post-earthquake assessment of seismic performance for a damaged RC building.
標題校舍補強工程經費之影響因素分析
作者楊元森、彭筠婷、黃羽璇、 邱聰智、鍾立來、黃世建
關鍵字校舍耐震補強、翼牆、擴柱、剪力牆、工程經費
摘要我國中小學校舍補強計畫從民國九十八年累積至今,已經普查了三萬多棟校舍建物,其中累積的補強案例資料具有相當大的分析價值。三萬多棟校舍所累積的評估資料及工程報告複雜且龐大,透過耐震補強資料庫得以妥善記錄補強各階段之資料。本研究依據校舍耐震補強資料庫,分析單價與地區、補強工法及耐震容量提升程度之關係,期能作為未來估算耐震補強工程經費之參考依據。
本研究針對校舍補強資料庫資料,在分析上分別藉由地區、工法以及耐震容量提升程度進行補強工程經費影響因素分析。影響補強工程經費的因素眾多,本文僅透過資料庫的資料探討單價與上述三種因素之間的關係。在校舍補強工法使用次數統計中,翼牆、擴柱及剪力牆為最常使用的補強方式,相較之下其它補強方式則為少數。本研究主要以翼牆、擴柱及剪力牆三種補強方式進行初步分析。
TitleConstruction cost analysis of school building seismic retrofit
AuthorYuan-Sen Yang,Yun-Ting Peng,Yu-Hsuan Huang, Tsung-Chih Chiou, Lap-Loi Chung, Shyh-Jiann Hwang
Keywordsschool building seismic retrofit, wing wall, RC jacketing, shear wall, construction cost
AbstractThe cases in the school building seismic retrofit have significant values for data analysis. The school building seismic retrofit data has been accumulated since 2009. More than 30,000 school building structures have been generally surveyed. More than 17,000 of them were preliminarily evaluated, and more than 10,000 of them which had significant risk of damage from earthquakes were evaluated. More than 6,000 of them have been retrofitted. As long as the analysis results are properly utilized, we will have more comprehensive understanding of construction cost, as well as potential for improving the administrative processes.
Based on the aforementioned database, this research analyzed the factors affecting the construction cost based on school locations, retrofit methods, and seismic capacity increment. In the statistics of the use of school building retrofit methods, it is found that wing walls, RC jacketing, and shear walls are the most commonly used retrofit methods. There are many factors that affect the project cost. This article studied the relationship between the retrofit cost and the above three factors through the data analysis.
標題考慮近斷層脈衝影響之隔震設計-以臺北盆地為例
作者楊甯凱、黃尹男、劉勛仁、趙書賢
關鍵字近斷層地震、隔震、鉛心橡膠支承墊、非線性動力歷時分析、強地動模型
摘要近斷層脈衝型震波因為含有中長週期速度脈衝,已為隔震結構之有效性帶來挑戰。然而台灣建築結構耐震設計規範並未提供具體作法來考慮脈衝型震波對隔震系統之影響,若因為脈衝型地震有可能造成隔震器過大位移而無法在近斷層區域採用,影響將十分重大。
本文提出一套流程將脈衝型地震的影響合理地納入隔震系統之設計,此設計流程不更動現行法規要求,建議以現行耐震設計規範公告之設計反應譜進行隔震系統之初步設計,再輔以定值法建立之脈衝地震檢核反應譜以及適當選取之脈衝型地震紀錄,透過非線性動力歷時分析進行隔震系統及上部結構之性能檢核。本文並以一棟位於臺北盆地的15層韌性抗彎鋼構建築為例,考慮山腳斷層發生規模7.3並產生長週期脈衝之地震,說明如何以本文提出之流程進行隔震系統之設計,包括檢核反應譜之建立、地震紀錄之選取與縮放、以及隔震系統及上部結構之性能檢核。
TitleDesign of base-isolation systems subjected to pulse-like ground motions
AuthorNing-Kai Yang,Yin-Nan Huang,Hsun-Jen Liu, Shu-Hsien Chao
KeywordsNear-Fault Ground Motions; Base Isolation; Lead-Rubber Bearings; Non-Linear Response-History Analysis; GMPE
AbstractModernbuilding codes do not provide clearguidelineson the design of base-isolation systems against pulse-like ground motions, which may produce excessive displacement demand for isolators and endanger the systems. A procedureis proposed in this paper to address the impact of pulse-like ground motionson isolation systems. The procedure involves 1) the development of an “evaluation spectrum” using newly developed Taiwan ground motion prediction equations and a model for the ratio of spectral accelerations of pulse-like to non-pulse ground motions, and 2) selection and scaling of pulse-like records for nonlinear response-history analysis of the isolated building of interest. This paper presents an example of a 15-story steel special moment resisting frame isolated using lead-rubber bearings to demonstrate the proposed procedure.
標題國道高速公路橋梁採隔震與基礎置換之耐震補強規劃設計
作者陳吟亘、蕭天任、吳明興、彭康瑜、陳國隆
關鍵字系統補強、隔震支承、換底工法 
摘要國內橋梁設計規範自民國76年版起,經過??耐震設計規範的改版更新,地震力多有提昇,為使既有橋梁符合現行規範之耐震能力標準,國道高速公路局自民國88年921集集地震後,持續推動橋梁耐震能力詳細評估,針對耐震能力不足者,分期辦理耐震補強工程。
橋梁基礎補強之工程經費較高,故優先採用「系統補強」的策略,研擬隔震或減震方案,當既有上部結構與橋墩之接合為故固接時,無法直接增設隔震支承,本文以國道3號高速公路「東山服務區跨越橋」為例,說明既有固接橋墩增設隔震支承之設計考量重點及方法。另外,部份橋梁有於河川行水區設置直接基礎的情形,因環境變遷與河床逐年下降,恐有基礎板底部承載層沖蝕疑慮,為一併辦理橋梁基礎耐震與耐洪能力的提昇,可考慮採用基礎置換工法(或稱換底工法),本文第二部份以國道3號高速公路「梅林溪排水橋」為例,說明直接基礎置換為樁基礎之施工步驟及方法。
TitleSeismic Isolation Retrofit and Foundation Replacement of Freeway Bridge
AuthorYin-Xuan Chen,Tien-Jen Hsiao,Ming-Shing Wu, Kang-Yu Peng, Guo-Long Chen
Keywordssystem of retrofit method, seismic isolator, foundation replacement method
AbstractTaiwan’s bridge seismic design specifications have evolved several version from 1987. In order to meet the seismic requirements under newest version specification. Freeway Bureau, MOTC has started existing bridge seismic capability evaluation and retrofitted after Chi-Chi Earthquake in 1999.
Because foundation retrofitting are expansive, we prefer to use “system retrofit method”. Conduct the feasibility studies on seismic isolation and damping devices. While the superstructure and pier are rigid connected, isolation bearing can’t install directly. An example of this is “Dong-Shan Bridge”. In this study, we explain the design considerations and methods of adding seismic isolation bearing to existing rigid piers. Furthermore, there are some cases where the spread foundation base will be scouring. An example of this is “Mei-Lin Bridge”. In order to increase earthquake and flood resistance at the same time. We use foundation replacement method to make spread foundation replace to pile foundation..
標題鄰近活動斷層耐震能力評估與補強-以嘉南大圳北幹一號橋為例
作者高墀修、蕭天任、吳明興、彭康瑜、陳國隆
關鍵字隔震橋、近斷層效應、耐震能力評估與補強、液態黏滯性阻尼器(FVD)
摘要隨著隔震技術的發展推廣,國內部分橋梁開始採用隔震支承作為其抗震的選擇,從早期第二高速公路的部份橋梁,到1999年921集集地震後遭到破壞的一些公路橋梁重建,隔震技術在國內橋梁工程的應用已將近三十年。交通部頒「公路橋梁設計規範」(97年)亦新增「隔震與消能設計」章節。由於鄰近活動斷層之地震,通常具有較長週期的脈衝震波,隔震橋亦具有較長振動周期特性,隨著經濟部中央地質調查所公告第一類活動斷層的增加,位於鄰近活動斷層之既有隔震橋,在近斷層地震波作用下,可能造成共振現象,產生超出原設計預期之較大變位。
本文以位在國3白河新化段的嘉南大圳北幹線一號排水橋為研究案例,利用隔震支承原型試驗結果,建立隔震橋梁分析模型,以探討一般遠域地震及近域地震對此隔震橋梁的影響與可行補強方法。研究結果顯示,因耐震規範地震力的改變,在一般遠域地震下,隔震支承即可能超出原設計位移量,而在近域地震下,當脈衝震波週期接近隔震橋梁振動週期時,位移將更加放大。經檢討研究,該橋之耐震補強方法,採用保留既有隔震支承,加裝液態黏滯性阻尼器(FVD),增加整體橋梁系統阻尼,以降低隔震支承位移反應。
TitleSeismic Evaluation and Retrofit of the Isolated Bridge near Active Faults: Chianan Irrigation, Beigan No. 1 bridge
AuthorChih-Siou Gao, Tien-Jen Hsiao, Ming-Shing Wu,Kang-Yu Peng,Guo-Long Chen
KeywordsIsolated bridge, Near-fault effect, Seismic Evaluation and Retrofit, Fluid Viscous Damper
AbstractWith the development of the seismic isolation technology in Taiwan, Seismic isolation bearing has been used in some bridges to resist earthquakes. Since the construction of freeway NO.3 and the reconstruction of the bridge damaged by Chi-Chi earthquake,isolation technology has been used in three decade.MOTC also added a chapter “Seismic Isolation and Energy Dissipation Design” to “Specification for Seismic Design of Highways and Bridges” (2008).But the pulses in the near fault ground motion have a large ­ displacement response which is exceed the design displacementon isolated bridges due to their long period property.
Take “Chia-nan Irrigation Channel No.1 Bridge” for example. We studied the effects of earthquakes near and far fault region on seismic behavior of isolated bridge, and suggest the retrofit method. This research shows that resultant displacement of the existing seismic isolated bearings may exceed the design displacement under the far-fault earthquake due to the seismic force increased.Furthermore, the resultant displacement will be much larger under the near-fault earthquake when the period of the isolated bridge is closed to the pulse period.Finally, we install fluid viscous damper (FVD) to increase the overall bridge system damping and to reduce the displacement response of the seismic isolated bearing.
標題以資料庫回歸台灣混凝土潛變預測公式並應用於預力橋梁長期變位分析
作者廖文正、高健鈞、黃禾程、黃炳勳、蔣啟恆
關鍵字資料庫、長期變形、潛變、預力橋梁、預力損失
摘要本研究統整台灣近40年的試驗資料並建立「台灣混凝土收縮與潛變資料庫」,並比較國內外資料庫後,發現台灣混凝土有漿體量高、低水灰比、低粒料勁度等特性,若直接套用國外預測式將不保守。故選用Bažant的Model B4為預測公式之基礎,對以上參數進行本土化修正,提出台灣普通混凝土之預測式。另外,近年來混凝土常添加卜作嵐材料,本研究將普通混凝土預測式延伸,針對添加卜作嵐材料之混凝土再進一步修正。混凝土潛變行為對於長跨預力橋梁長期變形影響甚鉅,為比較本土化與國外收縮潛變預測公式對橋梁長期變形的差異,本研究使用MIDAS Civil建立預力橋梁模型,套用國內外預測模型並比較分析結果,發現國外預測模型有嚴重低估變位與預力損失的現象,實務上若直接套用國外規範進行設計將會錯估使用年限與結構長期變位。
TitleRegression of Creep Prediction Formula of Concrete in Taiwan Basedon Database Analysisandits Applicationon Prestressed Concrete Bridge
AuthorWen-Cheng LIAO, Ho-Cheng HUANG, Jian-Jyun GAO , Ping-Hsun HUANG , Jumbo C.H. CHIANG
KeywordsDatabase, Long-term deformation, Creep,Prestressed concretebridge,Prestress loss
AbstractThis research integrates the test data of the past 40 years in Taiwan and establishes the “Shrinkage and Creep Database in Taiwan”. After comparing the domestic and foreign database, it is found that concrete in Taiwan has high cementitious material content, low water-cement ratio, and low aggregate stiffness, and it is not conservative if the foreign prediction model is directly applied. Therefore, Bažant’s Model B4 was selected as the basis of the prediction model, and the above parameters were localized and revised, and the prediction model of Taiwan ordinary concrete was proposed. In addition, this study extends the prediction model of ordinary concrete and revises the concrete with pozzolanic materials. Creep of concrete has a great influence on the long-term deformation of long-span prestressed bridges. In order to compare the difference between the domestic and foreign shrinkage and creep prediction models on the long-term deformation of the bridge, this study uses MIDAS Civil to establish a prestressed concrete bridge, and compares the analysis results between domestic and foreign prediction models. It is found that the foreign prediction models have seriously underestimated the deformation and prestress loss.

第三十五卷第四期 (期別138) (109年)

第三十五卷第四期 (期別138) (109年)

第十五屆結構工程暨第五屆地震工程研討會特刊(上集)

客座主編:周中哲、廖文義、洪崇展

標題以熔射覆膜技術提升摩阻型螺栓接合之滑移係數
作者陳誠直、謝宗成、張誠、李思維
關鍵字摩阻型接合、熔射覆膜、滑移係數
摘要摩阻型螺栓接合之設計理念為利用高強度螺栓鎖緊時,螺栓之預拉力將於接合鋼板上產生夾緊力,此夾緊力將進一步產生鋼板間的摩阻力。因此摩阻型接合將可提供螺栓剪力方向的抗剪強度,此抗剪強度與螺栓的夾緊力與鋼板間的滑移係數有關。本研究目的在探討以熔射覆膜技術於鋼板摩擦面上覆膜,提升摩阻型螺栓接合的滑移係數。實驗計畫設計試體以探討熔射覆膜材料(純鋁、鋁鎂合金)、覆膜厚度(150、300與450 µm)及鋼板鏽蝕對滑移係數之影響。實驗結果顯示,鋼板接合面之鏽蝕可提升滑移係數。於些微鏽蝕情況下,鋼板接合面僅噴砂未覆膜之平均滑移係數為0.74,純鋁覆膜之平均滑移係數為0.88,鋁鎂覆膜之平均滑移係數亦為0.88,皆高於設計規範中鋼板去除黑皮未塗裝表面之滑移係數0.33。熔射覆膜材料與覆膜厚度於滑移係數無顯著影響,但於鏽蝕情況下隨著覆膜厚度的增加會造成滑移發生後螺栓預力損失的提高。於鋼板接合面施以熔射覆膜鋁或鋁鎂合金,可提升摩阻型螺栓接合之滑移係數,增加摩阻型接合強度,達到減少接合尺寸及螺栓數量。
TitleIncreasing slip coefficient of bolted slip-critical joints using thermal sprayed coating technique
AuthorCheng-Chih Chen, Tsung-Cheng Hsieh, Cheng Chang, Sui-Wei Lee
KeywordsSlip-critical joint; thermal sprayed coating; slip coefficient
AbstractThe design philosophy of slip-critical joints is to utilize the friction force developed through the clamping force exerted by the pretension of the high-strength bolt. Thus, the slip-critical joint can have resistance in the direction of the bolt shear. This resistance is affected by the bolt clamping force and slip coefficient on the faying surface. The objective of this study is to increase the slip coefficient of bolted slip-critical joints by applying a thermal sprayed coating on faying surface. The specimens were designed to explore the effects of the coating material (aluminum or aluminum-magnesium alloy), coating thickness (150, 300 and 450 µm), and corrosion on the steel plate on the slip coefficient. The test results showed that exist of the rust increased the slip coefficient. In the case of slight corrosion, the blasted-cleaned faying surface resulted in an average slip coefficient of 0.74. The average slip coefficient was 0.88 for either the aluminum or aluminum-magnesium coatings. These slip coefficients are higher than the slip coefficient of 0.33 for unpainted clean mill scale specified in the design code. The coating material and thickness had insignificant effect on the slip coefficient. However, in the case of corrosion, the bolt pretension loss at slip was increased when the coating thickness was increased. The thermal sprayed coating of either aluminum or aluminum-magnesium on the faying surface can enhance the slip coefficient, increase the resistance of the slip-critical joint, and result in a smaller joint size and less high-strength bolts.
標題鋼筋混凝土梁滑移剪力設計之研究
作者王勇智、郭育廷
關鍵字New RC梁、塑性鉸區、塑鉸外移設計、滑移剪力破壞、斜向鋼筋
摘要本研究繼先前研究New RC梁設計,乃利用T擴頭鋼筋進行塑鉸外移設計時,雖有成功產生塑性鉸轉移,但卻有明顯垂直於梁向之滑移剪力裂紋發生;而塑性鉸區發生在傳統柱面時、或預鑄RC梁冷接縫在塑性鉸區時,亦有可能有類似滑移剪力裂紋破壞,因此引發本研究主題產生。故本研究主要目的是探討一般RC梁構件受震中,對於可能有潛在滑移剪力(sliding shear)破壞RC梁,如何檢查以及設計梁斜向鋼筋,以利抑制垂直剪力滑移破壞產生。
本文主要先收集先前計畫New RC梁與相關文獻一般RC梁之耐震測試數據,以統計方法檢核紐西蘭規範NZS 3101-2006判斷梁塑鉸區可能發生滑移剪力破壞規定之正確性。其結果為,建議以斷面剪應力0.25ඥf ୡᇱ(MPa)作為滑移剪力破壞之判別,且較適用於長跨梁(a/d≧2.5)。再者,對於梁構件塑性鉸區有潛在垂直滑移剪力裂縫產生時,則應考慮增設梁斜向鋼筋於塑性鉸區域,以利有效抑制此滑移剪力裂紋產生。本文亦參考其規範在斜向筋設計規定,以實驗作印證;結果為有加入斜向鋼筋RC梁,除了可以抑制垂直梁向滑移剪力裂縫發生外,亦可增進構材耐震性能。最後,綜合紐西蘭規定及本研究結果,乃建議一般跨度RC梁是否要設計斜向鋼筋之設計流程,以供參考。
TitleStudy on the sliding shear design for reinforced concrete beams
AuthorYung-Chih Wang, Yu-Ting Kuo
KeywordsNew RC, plastic hinge, hinge relocation design, sliding shear, diagonal reinforcement.
AbstractThis study follow up the previous research on the hinge relocation design by using T-headed bars. The main conclusion is that the T-headed bars as extra reinforcement can successfully relocate the plastic hinge zone from the column face to a distance away from the face, however the final failure mode of sliding shear occurred. The similar sliding shear failure could be also found in the plastic hinge zone occurred at the traditional column face, or in the precast cold connection located in the plastic zone. Therefore, the main purpose of this study is to discuss how to design the diagonal reinforcement of the beam to prevent the occurrence of vertical sliding shear cracks for the general RC beam members subjected to the major earthquake.
This article mainly collected the tested beams subjected seismic loading to verify the design of the sliding shear specified in the NZS 3101-2006. It was concluded that the sectional shear stress , 0.25ඥf ୡᇱ(MPa), to check the potential sliding shear failure occurred in the plastic zone of RC beams is suitable for normal-span beams (a/d≧2.5). Therefore, if the potential vertical sliding shear cracks may be occurred in the plastic hinge zone of RC beams, the diagonal reinforcement shall be considered. Meanwhile, the cyclic testing performed comparing two types of beams between with and without diagonal bars repealed that the RC beams with diagonal bars can prevent the sliding shear cracks from occurring, and improve their seismic resistance. The design flow chart for prevention of sliding shear failure occurred in RC beams is finally suggested in the paper.
標題幾何初始缺陷對具深寬翼鋼柱之抗彎矩鋼構架其耐震崩塌性能之影響
作者張廷浩、吳東瑜
關鍵字初始缺陷、鋼結構、抗彎矩構架、地震工程、崩塌性能
摘要熱軋型鋼由於軋制、運輸及安裝過程等影響,必定會存在初始變形,然而,幾何初始缺陷對特殊抗彎矩構架崩塌性能之影響,卻仍無詳細之研究或探討。因此,本研究以有限元素模擬,探討初始幾何缺陷對具深寬翼鋼柱之四層樓及八層樓之特殊抗彎矩構架其耐震崩塌性能之影響。模擬結果顯示,不同初始幾何缺陷的施加可改變鋼柱之挫曲行為,但對抗彎矩構架崩塌行為之效應於不同地震歷時下並無一致性。對於四層樓且軸力小之構架,初始幾何缺陷因構架在不同地震歷時下之崩塌模式不同,對崩塌性能之影響較不顯著;對於八層樓構架與軸力大之四層樓構架,因鋼柱挫曲於不同地震歷時下之行為較一致,因此初始幾何缺陷對構架崩塌性能影響較為明顯。然而平均而言,以挫曲模態疊加法所建立之初始缺陷,因其對崩塌性能之影響不大且可能會帶來正面影響,加上使用高擬真及高精度之有限元素模擬時,構件在加載初期即可生成初始缺陷,故建議以高精度之模擬探討構架於地震歷時下之崩塌行為時,可忽略初始幾何缺陷之效應。
TitleEffect of geometric initial imperfections on seismic collapse capacity of steel special moment frames with deep columns
AuthorTing-Hao Chang ,Tung-Yu Wu
KeywordsGeometric initial imperfections; steel special moment frames; seismic collapse capacity
AbstractAlthough wide-flange (W-shape) steel members are known to have initial geometric imperfections (IGIs) due to fabrication and installation, the effect of IGIs on seismic behavior of steel special moment frames (SMFs) is still not well understood. To address this shortcoming, seismic collapse capacity of 4-story and 8-story prototype SMFs with various types of IGIs is computationally evaluated to quantify the effect of IGIs created by combining buckling shapes. The results show that even though IGIs can affect column buckling behavior and frame collapse mode under certain conditions, their effect on seismic collapse capacity is generally small and inconsistent. Their influence also greatly depends on the directions of applied IGIs and column buckling shapes and may be positive if the directions are misaligned. As a result, it is suggested that initial geometric imperfections need not be incorporated in high fidelity numerical models with high precision, which can generate their own IGIs when loaded.
標題箱型鋼柱於不同寬厚比軸力及近斷層地震下的耐震行為與背骨曲線發展
作者周中哲、陳冠維、林德宏
關鍵字高強度銲接箱型鋼柱側向耐震實驗、高軸力柱構件、近斷層載重、背骨曲線
摘要本研究藉由分析7層樓挫屈束制斜撐構架受遠域及近斷層地震之反應,發展一樓鋼柱的遠域及近斷層側向載重位移歷時,並以實驗方式探討高強度銲接箱型鋼柱受遠域及近斷層載重作用下之耐震行為。自國內外地震中選取11組近斷層和11組遠域地震歷時紀錄,調整至最大考量地震(MCE)等級進行非線性歷時分析,發展一樓鋼柱受近斷層地震之側向載重歷時,含有自-2%到4%側位移角的位移脈衝,及2.5%的殘餘側位移角,藉此探討臺灣高強度鋼柱於中、高軸力下之耐震行為。試驗參數包括柱寬厚比、軸力比及近斷層載重歷時,共規劃6組使用SM570MC鋼材製造之全尺寸銲接箱型鋼柱試體,寬厚比介於11~21。試驗顯示寬厚比較小之銲接箱型鋼柱可有效減緩鋼板局部挫屈;美國AISC 341 (2016)之高韌性構件寬厚比限制為12.9(以標稱降伏強度Fyn=420 MPa及材料超強因子係數Ry=1.2為例),而臺灣鋼結構極限設計規範(2010)對全滲透銲接箱型鋼柱之寬厚比放寬至21,兩者差異極大,較寬鬆的鋼柱寬厚比無法確保在承擔中高軸壓力下的鋼柱在大位移下(側位移角>3%)的耐震行為,在高耐震區使用銲接箱型鋼柱承擔中高軸壓力(25~40%Py),建議應採用美國AISC 341 (2016)之高韌性柱構件進行設計。本研究並藉由搜集以往的實驗資料發展鋼柱的側向位移背骨曲線,預測鋼柱的側力與側位移行為,大幅改善ASCE 41(2013)及NIST(2017)對箱型鋼柱背骨曲線預測在高軸力下過度保守及低軸力下不保守的情形。
TitleSeismic Performance and Backbone Curve Development of Steel Box Columns Considering Compactness Ratios, Axial Loads and Near-Fault Motions
AuthorChung-Che Chou, Guan-Wei Chen, Te-Hung Lin
KeywordsSteel built-up box column, High axial compression force, Lateralcyclic test, Cyclic backbone curve
AbstractThis paper presents the seismic evaluation of high-strength steel columns in a seven-story buckling-restrained braced frame under two sets of 11 far-field motions and 11 near-fault motions, representative of maximum considered earthquake (MCE) level. The proposed near-fault displacement protocol contains a large displacement pulse from -2% to +4% drift with several small displacement cycles and a residual drift of 2.5%.The AISC 341 (2016) has a more stringent width-to-thickness (b/t) limit for highly ductile hollow box columns (HBCs) than the AIJ (2010) or Taiwan Code (2010), resulting in significant thickness difference in design. For example, the b/t limits for a highly ductile box column member with a nominal yield strength, Fyn=420 MPa, and an over-strength factor, Ry=1.2, are 12.9 and 21 based on AISC 341 (2016) and Taiwan Code (2010), respectively.Moreover, the cyclic backbone curves based on ASCE 41 (2013) and NIST (2017) underestimate the post-buckling flexural strength of HBCs, particularlyin high axial compression force.The authors conducted cyclic tests of six full-scale, built-up HBCs using SM 570M steel with the actual yield strength of 460-530 MPa using standard and proposed loading protocols.The gathered test data, supported by more test data in this work, are analyzed by a multiple regression method to obtain empirical formulations for the backbone curves of box columns that can predict the maximum column moment, plastic rotation and post-yield hardening stiffness. The proposed formulation reasonably predicts the first-cycle envelope curves of built-up HBCs, significantly improving prediction results based on both ASCE 41 (2013) and NIST (2017).
標題TMD於離岸風機結構減震之理論與振動台試驗研究
作者林錦隆、盧煉元、雷凱婷、 劉光晏
關鍵字離岸風機、調諧質量阻尼器、套筒結構、振動台試驗、減震技術、簡化模型
摘要風能兼具環保性及永續性,因此台灣近年於台灣海峽上建造風力發電機,實施海上風電場之計畫。但是台灣位處地震帶,為確保海上風力發電機的安全性及可靠性,避免風機結構或內部設備在受波浪、風及地震作用時,因振動量過大產生不穩定甚至損壞的情形發生,因此本文擬以理論與實驗方法探討調諧質量阻尼器(tuned mass damper, TMD)作為離岸風機結構減震元件之可行性。TMD為一種廣泛應用於高聳結構之有效減震技術。與其他減震裝置相比,TMD系統可整合為風機結構的一部份,因此對結構系統的影響較少。本文乃參考美國再生能源研究中心(NREL)所訂定之5-MW套筒式風機結構標準規格,製作1/25比例之套筒式風機縮尺模型及其TMD,以進行振動台測試。同時,為方便理論分析之用,本文乃針對套筒式風機支撐結構建議一簡化之分析模型,並推導其連體運動方程式,期以理論分析與實驗觀察,了解TMD於離岸風機之真實減震效益。本文透過縮尺風機支撐結構模型之振動台試驗,驗證所建議理論分析模型的正確性。同時,藉由比較裝設與未裝設TMD之風機結構振動台試驗結果,探討TMD對於套筒式風機支撐結構各自由度之減震效益。
TitleTheoretical and experimental study on vibration mitigation of off-shore wind-turbine using TMD
AuthorGing-Long Lin, Lyan-Ywan Lu, Kai-Ting Lei, Kuang-Yen Liu
Keywordsoffshore wind turbine, tuned mass damper, jacket-type structure, shaking table test, supporting structure, seismic vibration reduction, simplified model.
AbstractWind energy is clean and sustainable. Taiwan is establishing offshore wind farms using wind turbines in the Taiwan Strait. Since Taiwan is located in an earthquake active zone, in order to ensure the safety and reliability of offshore wind turbines under waves, wind and earthquakes, this study aims to investigate the suitability of using a tuned mass damper (TMD) to reduce the vibration of offshore wind turbine supporting structures. The TMD can be integrated as a part of the wind turbine structure, so it has less influence on the supporting structure of a wind turbine. In this study, based on the specifications of a 5-MW jacket-type offshore wind turbine suggested by the National Renewable Energy Research Center (NREL, USA), a 1/25 scaled-down test model and its corresponding TMD were fabricated and tested by a shaking table. Additionally, for numerical simulation, a simplified theoretical model for a jacket-type offshore wind turbine structure is proposed and its equation of motion was derived in this study. The proposed theoretical model was verified both in time domain and frequency domain using the result of the shaking table test. The experimental seismic responses of the offshore wind turbine model before and after the installation of TMD were compared, and the control performance of the TMD system for vibration mitigation of the wind turbine structure was evaluated in this study.
標題無預力且部分無握裹鋼絞線橋柱之耐震行為
作者歐昱辰、吳振維、Ade Yuniati Pratiwi
關鍵字橋柱、近斷層地震、殘餘變位、自復位、後降伏勁度、保護層
摘要近斷層地震所產生的脈衝型震動,容易造成傳統鋼筋混凝土橋柱於震後產生較大的殘餘變位,嚴重危害橋梁安全性與震後服務性。本研究開發先進自復位橋柱,利用高強度鋼絞線作為橋柱之彈性元件,使其於傳統竹節縱向鋼筋降伏後仍保持彈性,可降低橋梁在近斷層地震後常見之大殘餘變位。本研究完成了四座單曲率柱反覆載重試驗,包含一座對照組試體與三座先進自復位橋柱試體,試驗參數為鋼絞線的使用與不同的保護層厚度。
根據試驗所得到的後降伏勁度比α及真實保護層厚度C c,A ,利用線性回歸建立了橋柱深度保護層厚度比與後降伏勁度比之線性回歸公式,並發現於同一試體中,受壓側之保護層厚度越低者,具有越高的後降伏勁度k2 及後降伏勁度比α。橋柱後降伏勁度之維持,於拉力區使用不降伏的鋼絞線固然重要,壓力區強度的維持也是關鍵因素。由於拉力區鋼絞線維持彈性,因此在橋柱傳統縱向鋼筋降伏後,拉力區之拉力仍然持續顯示上升,為維持斷面力平衡,斷面壓力區之壓力得隨之升高,試驗結果顯示,前述升高的壓力易造成壓力區保護層混凝土較早壓碎,而壓力區的損失會造成斷面為維持力平衡,使得拉壓合力距離縮短,若保護層因施工誤差導致過厚,則會造成斷面彎矩無法再顯著提高,使後降伏勁度之維持不如設計預期。
TitleSeismic Behavior of Bridge Columns with Partially Unbonded and Non-prestressed Steel Strands
AuthorYu-Chen Ou, Jhen-Wei Wu, Ade Yuniati Pratiwi
KeywordsColumns, near-fault ground motions, residual displacement, self-centering, post-yielding stiffness, cover concrete
AbstractThe impulse vibrations generated by near-fault earthquakes are likely to cause large residual displacements of RC bridge columns after the earthquake, which seriously endangers the safety and the serviceability of the bridge. A new type self-centering bridge column is developed in this research. The new column uses high-strength steel strands as the elastic element, which can reduce the large residual displacement of the bridge after the near-fault ground motions. In this study, four large-scale columns were tested using single-curvature cyclic loading, including a conventional column and three new self-centering bridge columns. The test parameters were the use of steel strands and different cover concrete thicknesses.
According to the post-yielding stiffness ratio and the actual thickness of the cover concrete from the test results, a linear regression formula for the ratio between the depth of the column to the thickness of the cover concrete and the post-yielding stiffness ratio was established. For the same specimen, the lower the thickness of the cover concrete on the compression side, the higher the post-yielding stiffness. The use of steel strands in the tension zone is important to maintain the post-yield stiffness of the bridge column. The maintenance of the strength in the compression zone is also an important factor. Because the steel strands in the tension zone remain elastic, the tension in the tension zone continues to increase after the conventional longitudinal steel bars yield. Due to force equilibrium of the section, the compression force has to increase accordingly. Test results show that the aforementioned increased compression force is likely to cause early crushing of the cover concrete of the compressive zone, which leads to the loss of the compressive zone and decrease the distance between the tension and compression resultant forces of the section. The test results of CSC3 show that when the ratio between the depth of the bridge column to the thickness of the cover concrete is 30, the average post-yield stiffness ratio can reach 5.7%.

第三十五卷第三期 (期別137) (109年)

第三十五卷第三期(期別137)(109年)

標題SM570M-CHW 高強度鋼箱型柱翼厚與梁翼板高程偏心對電熱熔渣銲破壞效應
作者黃昱竣、胡祐瑋、覃志光、蔡青宜、李昭賢、莊勝智、 林克強、蔡克銓
關鍵字鋼箱型柱、鋼梁柱接頭、SM570M-CHW 鋼、電熱熔渣銲、圓周刻痕拉伸試驗、鋼材破裂預測模型、有限元素模型分析、橫隔梁翼交疊高度
摘要箱型柱具雙強軸特性,在台灣鋼結構中應用普遍,為將梁彎矩傳入柱構件,箱型柱中與梁翼相對應之高程須置入內橫隔板,內橫隔板與箱型柱之銲接工法通常採用電熱熔渣銲(Electro-Slag Welding, ESW),而為減少柱斷面積,高強度 SM570M-CHW 鋼的應用也漸普及。本研究利用高強度鋼材探討箱型柱中 ESW 的耐震行為,並採用既有的鋼材破壞預測模型探討ESW 是否會破裂與破裂時機。本研究以 11 組 ESW 元件單向拉伸試驗與 4組實尺寸梁柱接頭反覆載重試驗探討柱翼板厚度與梁翼板偏心對於 ESW 破壞的效應,試驗結果顯示 ESW 元件僅受單向拉力作用時,只要「梁翼橫隔交疊高度」小於等於零,且偏心大於一倍柱翼板厚度,ESW 就會發生破壞;但「梁翼橫隔交疊高度」大於或等於 1/4 梁翼厚時,偏心超過一倍柱翼板厚度仍不會於 ESW 發生破壞。實尺寸梁柱接頭反覆載重試驗中則證明當柱翼板厚度由 25mm 提升至 45mm 時,ESW 由原先 3%層間位移角發生破壞改善至層間位移角達 5%尚未發生破壞。為探討 ESW 元件能否有效模擬梁柱接頭中的 ESW 銲道受力行為,本研究亦建立圓周刻痕試棒有限元素模型獲得材料參數之後,再進行 ESW 元件有限元素模型分析,並進行 ESW 關鍵區域破裂預測,結果顯示不論梁翼對 ESW 往梁腹方向亦或是反向偏心,有限元素模型皆能預測出 ESW 元件試體破壞時機且誤差小於 12%;進而建立實尺寸梁柱接頭有限元素模型模擬接頭內 ESW 銲道在反覆載重作用下之受力行為,結果顯示當柱翼板厚度由 25mm 增厚至 45mm 時,應力集中現象明顯減緩,且尖端開口位移下降至原先 1/3 倍,並可準確預測梁柱接頭內ESW 破壞時機。本研究亦以柱翼板厚度、梁翼板厚度及橫隔梁翼交疊高度為參數進行研究,探討不同參數配置對 ESW 銲道關鍵區域破壞時機之影響。分析結果顯示,當柱翼板厚度與橫隔梁翼交疊高度提升,以及梁翼板厚度減少時,可降低 ESW 開裂之機會。本研究建議柱翼板厚度宜大於或等於橫隔板厚度,且橫隔梁翼交疊高度不宜低於四分之一倍之橫隔板厚度,以避免 ESW 之脆性破壞。
TitleEffects of SM570M-CHW steel beam flange eccentricity and box-column flange thickness on electro-slag welding failure
AuthorYu-Jun Huang, You-Wei Hu, Chih-Kuang Chin, Ching-Yi Tsai, Chao-Hsien, Li,Sheng-Jhih Jhuang, Ker-Chun Lin, Keh-ChyuanTsai
Keywordssteel box column, SM570M-CHW steel, electro-slag welding, circumferentially notched tensile test, steel fracture prediction model, finite element analysis, overlapping distance of beam flange and diaphragm
AbstractSteel box columns are widely used in seismic steel building structures in Taiwan. In order to effectively transfer the beam-end moment to the column, diaphragm plates are welded inside the box column at the same elevations of the welded beam flanges. Electro-slag welding (ESW) procedure is common applied to attach the diaphragm plates to the column. Recently, the SM570M-CHW grade high strength steel is prevailingas it reduces the column sizes. In this study, four full-scaled welded SM570M-CHW steel beam-to-column (BC)joint specimens and eleven ESW component specimens were fabricated and tested. The key design parameters of these specimens include column flange thickness, beam flange eccentricity with respect to the diaphragm plate. This study investigates the applicability of stress modified critical strain and degraded significant plastic strain modelsin predicting the crack initiation fracture of the diaphragm-to-column ESW joint. The ESW component specimens were subjected to monotonic tensile loads, while the welded BC joint specimenswere subjected to cyclically increasing displacement to investigate the effects of beam flange eccentricity and column flange thickness on the ESW fractures. Test results show that when the ESW was subjected to monotonic tension only, it could fracture when the “overlapping distance of beam flange and diaphragm” (OD) was smaller or equal to zero. On the contrary, it remained intact even when the ODwas greater or equal to thickness of beam flange. Cyclic test results of the welded BC joints show that the connection with the 25mm thick column flange failed at the 3% inter-story drift (IDR) cycle, while the specimen with the 45mm column flange went through 5% IDR cycle without failure. The finite element model analysisresults show that when the column flange thickness increases from 25mm to 45mm, the stress concentrations are reduced and the crack tip opening displacement is decreased by 3 times. This study also carried out parametric study, focusing on the effects of the column flange thickness, the beam flange thickness and the OD on ESW fracture. Results show that increasing the column flange thickness, or the OD and decreasing the beam flange thickness reduce the stress concentration near ESW. In order to avoid the ESW fracture, the results of this study suggest that column flange thickness be equal to or larger than diaphragm or beam flange thickness; and the ODbe larger than one quarter of the diaphragm or beam flange thickness.
標題地動特性預測模組與智慧型隔減震控制系統之研發
作者蕭迦恩、林光奕、林子剛、 盧煉元
關鍵字地表運動特性,支持向量機,隔減震控制,基因演算法,模糊控制
摘要近年來隔減震控制與地震預警的研究愈加受到重視,在地震工程領域中,地表運動特性除了常見的加速度、速度與位移的極值,還可分類為近斷層地表運動(near-fault ground motion)與遠域地表運動(far-field ground motion)。根據過去結構隔減震控制的相關研究,不同地表運動特性對於結構反應之控制結果影響甚鉅,故此研究試圖提出地表運動特性之預測模組,於地震主震波到來前預測此地震之地表運動特性,以優化隔減震之即時控制成效。本研究建立近斷層地表運動與遠域地表運動之資料庫,利用六項初達波特徵參數以及地表動態頻譜的高頻能量累加參數,以監督式機器學習—支持向量機建立地表運動特性預測模組。為了進一步開發智慧型隔減震即時控制系統,研究中採用槓桿式可變勁度隔震系統(Leverage-type Stiffness Controllable Isolation System, LSCIS)作為隔減震原型機構,此半主動控制機構可透過調整其控制律之控制參數,改變有效隔震勁度以即時控制結構動態反應。本研究亦將數個相異類型且具指標性的地表運動所對應之控制參數透過基因演算法最佳化,並以模糊控制建立地表運動與控制參數之關係模型,開發出智慧型隔減震即時控制系統。
TitleDevelopment of Ground Motion Characteristics Prediction Module and its Application to the Control of Intelligent Isolation System
AuthorChia-En Hsiao, Kuang-Yi Lin, Tzu-Kang Lin, Lyan-Ywan Lu
KeywordsGround motion characteristics, Support vector machine, Structural control, Genetic algorithm, Fuzzy control.
AbstractIn recent years, researches on structural control combining earthquake early warning have been widely studied. In the field of seismic engineering, ground motions can be mainly classified into near-fault and far-field ground motions. While the ground motion characteristics have a great influence on control performance; however, the existing earthquake early warning system can only predict the peak ground acceleration, and the optimal control efficiency cannot be promptly achieved. Therefore, a prediction module for ground motion characteristics is proposed in this study. A database of near-fault ground motions and far-field ground motions is first collected, and the six p-wave features and the high-frequency energy accumulations of the ground dynamic spectrum are used to establish the ground motion characteristic prediction module by utilizing support vector machine. In order to develop the intelligent structural control system, the Leverage-type Stiffness Controllable Isolation System (LSCIS) is used as the structural control mechanism. The effective isolation stiffness of the LSCIS can be swiftly changed to control the dynamic response of the structure. The control parameters corresponding to different types of ground motion are optimized by genetic algorithm, and fuzzy control is adopted for the intelligent isolation system.
標題壓電調諧質量阻尼器於垂直振動減振與能量擷取
作者賴勇安、周維苓、鍾立來
關鍵字調諧質量阻尼器、壓電材料、能量擷取、垂直振動、最佳化設計
摘要近年來人類對於能源的需求持續攀升,然而為因應氣候變遷,將迫使減少石化能源的使用,因此尋求更多更環保的能量來源,以因應未來需求,為當前各國的研究重點之一。由於土木結構與材料技術的發展,結構物設計建造越趨經濟,橋梁結構重量漸趨輕量,外觀也逐趨細長,結構週期也隨之延長,使得橋梁結構也較易受人行等外力激振。土木工程師為了有效降低此振動量,逐以加裝調諧質量阻尼器(Tuned Mass Damper, TMD)的方式,透過調諧質量阻尼器的振動頻率與結構自然頻率調諧,吸收結構的振動能量,並透過自身之阻尼器來消散傳入之振動能。然此能量為一綠色能源,如能量就此消散,實為浪費,有鑑於此,本文研究「壓電調諧質量阻尼器 (Piezoelectric Tuned Mass Damper, Piezo-TMD)」,以壓電材料將吸收之機械振動能轉換為電能,以便進行能量擷取。本文首先提出壓電調諧質量阻尼器之模型,推導出壓電調諧質量阻尼器系統之運動方程式。與一般調諧質量阻尼器不同,壓電調諧質量阻尼器除了力學之運動方程式外,另有一電路方程式,且兩方程式互為耦合。本文之壓電調諧質量阻尼器設計目標為能量擷取的平均功率最大化,並以一人行橋結構進行數值模擬,結果顯示壓電調諧質量阻尼器具有與傳統調諧質量阻尼器相近之結構減振效果,並可將人行外力所引致之振動能轉為可再利用之電能。且模擬結果顯示,壓電調諧質量阻尼器除其機械之自然頻率需與結構相調諧外,其電路之自然頻率也需與結構調諧,方可使結構之振動能量有效利用共振效應轉移至電路上。
TitlePiezoelectric Tuned Mass Damper for Vertical Vibration Reduction and Energy Harvesting
AuthorYong-An Lai, Wei-Ling Chou, Lap-Loi Chung
Keywordstuned mass damper, piezoelectric material, energy harvesting, vertical vibration reduction, optimal design
AbstractIn recent years, the energy consumption has continually grown. However, due to climate change, the use of fossil fuel to generate electrical power forces to be reduced. Therefore, looking for environmental friendly energy sources is one of the current research priorities. Because of the development of civil engineering technology, the design and construction of structures turn into more economical. The weight of the bridge structure is becoming lighter, the appearance is accomplishing slender, and the structural period is therefore prolonged, making the bridge structure more susceptible to external forces such as pedestrian loads. In order to effectively reduce the vibration, civil engineers designed and installed Tuned Mass Damper (TMD). Through the tuning of the natural frequency of TMD to the structure, the vibration energy of the structure was absorbed and then dissipated by dashpot. However, this absorbed energy is a kind of green energy source to waste to be dissipated. In view of this, this article studies “Piezoelectric Tuned Mass Damper (Piezo-TMD)”, which uses piezoelectric materials to convert the mechanical vibration energy into electricity for energy harvesting. This research proposes the model and derives the equation of motion of the Piezo-TMD system. Different from the conventional TMD, Piezo-TMD has a circuit equation in addition to the mechanical equation, and these two equations are mutually coupled. The design goal of the Piezo-TMD in this paper is to maximize the average power for energy harvesting, and the numerical simulations are carried out with a pedestrian bridge structure. The simulation results show that the Piezo-TMD achieves the similar performance of vibration reduction as the conventional TMD and thus the vibration comfort requirement can be satisfied. Moreover, the vibration energy is further transferred to electricity for harvest to verify the feasibility of Piezo-TMD. In addition to tuning the mechanical natural frequency of the Piezo-TMD, the natural frequency of the circuit also needs to be tuned to the structure, so that the vibration energy of the structure can be effectively transferred to the circuit by using the resonance effect.
標題五螺箍筋柱之雙曲率反覆載重試驗與離散計算剪力模型
作者歐昱辰、李哲諺
關鍵字剪力強度、五螺箍、柱、離散計算剪力模型、反覆載重
摘要五螺箍筋運用在正方形斷面鋼筋混凝土柱已證實具有優於傳統方箍筋的圍束能力。本研究目的在於探討五螺箍筋之剪力強度,設計雙曲率反覆載重試驗,測試大型剪力破壞五螺箍柱與傳統方箍柱對照組。測試結果指出,箍筋體積比相同、鋼筋降伏強度與混凝土抗壓強度相似的情況下,五螺箍柱展現稍弱於傳統方箍柱的極限剪力強度,所有五螺箍柱過最大剪力強度後力量衰退速率皆小於傳統方箍柱。高軸力五螺箍柱之破壞模式為箍筋拉斷,而高軸力傳統方箍柱之破壞模式為彎鉤鬆脫導致過早破壞。本研究發展一套改進離散計算剪力模型用來計算五螺箍柱剪力強度。與試驗結果比較,改進離散計算剪力模型能保守估計五螺箍剪力強度,此外,本模型具有與規範剪力公式用於傳統方箍剪力強度之相似保守程度。
TitleDouble-curvature cyclic test of columns with five-spiral reinforcement and discreet computational shear strength model
AuthorYu-Chen Ou and Jhe-Yan Li
Keywordsshear strength; five-spiral reinforcement; columns; discreet computational shear strength model; cyclic test.
AbstractFive-spiral reinforcement has been proved to have superior confinement capability to conventional rectilinear hoops. The objective of this research is to investigate the shear strength of five-spiral reinforcement. Large-scale columns with five-spiral reinforcement and control columns with conventional rectilinear reinforcement were tested in this research using double-curvature cyclic loading. Test results showed that with the same volume of reinforcement and similar reinforcement yield strength and concrete compressive strength, the shear strength of columns with five-spiral reinforcement was slightly less than that with conventional rectilinear reinforcement. However, the strength degradation after the peak strength for columns with five-spiral reinforcement was slower than that for columns with conventional rectilinear reinforcement. Under high axial load, the failure mode of columns with five-spiral reinforcement was fracture of spirals.In contrast, the failure mode of columns with conventional rectilinear reinforcement was the loosening of hook anchorage of the reinforcement. An improved discreet computational shear strength model is developed in this research and validated by the test results. The model can be conservatively used for estimating the shear strength of five-spiral reinforcement. Moreover, the model shows a conservatism for estimating the shear strength of five-spiral reinforcement similar tothat shown by the code shear strength equations for conventional rectilinear reinforcement.
標題結合振形之微振索力估算法中量測點位配置對精度的影響
作者陳建州、吳文華、陳欣怡、 賴國龍
關鍵字微振法、索力估算、振形、有效振動長度、多點同步量測、量測點位配置
摘要為克服複雜錨定條件造成微振索力估算法的較大誤差問題,本研究團隊近年來提出一項創新的方法,藉由導入振形函數正弦分量的擬合來決定各振態有效振動長度以排除索力計算公式中複雜邊界條件的影響,而其關鍵則在如何經由多點同步量測精準重現振形函數之正弦分量。本文首先根據理論推導出的頻率方程式與振形函數闡述此一索力量測方法的基本原理;接著再進一步利用有限元素模型,於考慮實測作業限制條件下建立包括數目與間距等量測點位配置準則;最後則進行實驗室單根鋼絞線索力量測,充分驗證所擬定量測點位配置準則的適用性以及對應的索力估算精度。
TitleEffect of sensor deploymentonen on the accuracy of ambient vibration method incorporating mode shape functions for cable tension estimation
AuthorChien-Chou Chen, Wen-Hwa Wu, Shin-Yi Chen and Gwolong Lai
Keywordsambient vibration method, cable tension estimation, mode shape, effective vibration length, multiple synchronous measurements, sensor deployment
AbstractThe complicated boundary conditions resulted from the anchorage systems at both ends usually deteriorate the accuracy of the ambient method for cable tension estimation. Motivated by tackling such a problem, a novel method incorporating the mode shape functions was recently proposed by this research group. More specifically, the fitting for the sinusoidal components of mode shape functions was adopted to determine the effective vibration length for each mode such that the interference from the complicated boundary conditions can be eliminated. The success of this method is most critically decided by the accurate reproduction of the sinusoidal components of mode shape functions based on multiple synchronous measurements. The current paper first explains the basic concepts of this cable tension estimation method with the theoretically derived mode shape functions and frequency equations. The finite element models are further employed to evaluate the accuracy of this method and establish the guidelines for the preferred sensor deployment in measurement points and spacing with the consideration of practical measurement limitations. Finally, the applicability of the developed guidelines and the corresponding accuracy in tension estimation are verified by demonstrative laboratory experiments with a prestressed strand.

第三十五卷第二期 (期別136) (109年)

第三十五卷第二期(期別136)(109年)

標題混凝土潛變及自體收縮對鋼管混凝土柱之影響研究及設計建議
作者游雅如、陳振川、廖文正
關鍵字鋼管混凝土、潛變、自體收縮、應力轉移、B4-TW潛變收縮模式
摘要鋼管混凝土柱(Concrete-filled steel tubular column,簡稱CFT柱)具高強度、高韌性,被視為具有良好耐震性能的結構構件。早期鋼管內灌混凝土是為了增加構件的側向勁度,並延緩挫曲行為的發生。近年工程師開始將核心混凝土納入實際承重單元。CFT柱受力後,混凝土潛變就會隨時間持續發展,而柱構件為了保持其斷面力平衡,混凝土會將承擔的部分軸力移轉至鋼管,這些移轉量可能會使鋼管降伏,影響結構物的安全。此外,低水膠比的高強度自充填混凝土,也會產生大量自體收縮,使構件內混凝土及鋼管間應力移轉現象愈嚴重。本研究以有限元素分析軟體ABAQUS建置三維鋼管混凝土柱模型,選擇可反映台灣混凝土特性之B4-TW潛變收縮模式,研究混凝土潛變及自體收縮引致之構件內部應力移轉的情形。模擬結果顯示,在初始鋼骨應力設定為0.6f_y的情況下,無論荷載是否偏心,考慮混凝土潛變收縮效應的最終鋼應力皆有機會超出「鋼構造建築物鋼結構設計技術規範」檢核標準。而且在使用高強度自充填混凝土及構件高寬厚比的極端情況下,鋼應力可上升0.33f_y,將大幅超過原始設計值。未來設計應注重長期荷載效應,並考量混凝土長期變形對於鋼管應力的影響。
TitleStudy of the Influence of Creep and Shrinkage on Concrete-Filled Steel Tubular Columns and Design Suggestions
AuthorYa-Ju Yu, Jenn-ChuanChern, Wen-Cheng Liao
KeywordsCFT, creep, autogenous shrinkage, stress transfer,B4-TW creep and shrinkage prediction model
AbstractConcrete-filled steel tubular (CFT) columns show not only high strength and high ductility but also exhibit favorable seismic performance. The primary intent of concrete infill is to increase lateral stiffness of member and delay the local buckling of the steel tubular. Once concrete is subjected to load, development of concrete creep begins. In order to maintain the equilibrium of forces of CFT section, part of axial load of concrete will be transferred to steel tubular which leads to the growth of steel stress. Furthermore, high strength self-consolidating concrete (SCC) with low water-to-cement ratio intensifies the rise of steel stress in CFT columns on account of high autogenous shrinkage.A three-dimensional finite element model of CFT column, which takes account of the phenomenon of concrete creep and shrinkage, is developed to evaluate stress transfer between concrete and steel in ABAQUS. B4-TWcreep and shrinkage prediction model is also applied to reflect a characteristic of high amount of paste in concrete mix designs in Taiwan owing to the soft nature of coarse aggregates. The analysis results show that under the condition of initial steel stress of 0.6݂௬, the final steel stress of CFT column is probably not qualified according to “Design and Technique Specifications of Steel Structures for Buildings” owing to the long term deformation of infilled concrete whether the load is eccentric or not. In the extreme case of high concrete compressive strength of SCC and high diameter to thickness ratio, the steel stress significantly exceeds the original design value with 0.33݂௬. It is suggested that relevant specifications should be revised accordingly in Taiwan.
標題考慮鋼筋腐蝕影響之RC建築物耐震能力初步評估法
作者邱建國、詹宗翰、蔡宜靜
關鍵字初步耐震能力評估、目視調查、劣化度、鋼筋腐蝕
摘要本研究參考過去計劃成果以建立鋼筋腐蝕構件之力學評估模型,對腐蝕構件之塑鉸容量進行折減,除進行相關試驗資料之比對與驗證外,根據文獻所收集一般典型校舍及街屋的常用構件尺寸及斷面配筋,計算柱構件於不同劣化程度下之強度折減係數,提供評估人員搭配既有之初步耐震能力評估法使用。換言之,評估人員可參考RC建築物耐久性能診斷技術手冊之建議,依目視調查構件外觀之劣損以判定其劣化程度,並參考本文建議之折減係數修正其強度。本文最後以一既有校舍為範例,考量構件於不同劣化程度下之耐震能力,以國震中心所建立之TEASPA搭配結構分析軟體ETABS進行詳細評估,並與本研究所提供之初步耐震能力評估進行比對,以了解其合適性。
TitlePreliminary Seismic Performance Evaluation Method of RC Buildings Considering the Corrosion Effect of Reinforcement
AuthorChien-Kuo Chiu, Zong-Han Jhan, Yi-Jing Cai
KeywordsPreliminary seismic performance evaluation, Visual inspevtion, Deterioration de gree, Corroded reinforcement
AbstractThis research establishes a mechanical evaluation model of a corroded RC member and reduces its plastic hinge capacity on the basis of the past research project. In addition to do the comparison and verification with the relevant experiment data, this research collects the general information of the size of column members and reinforcement arrangement in a typical reinforced concrete building and street house for investigation on the reduction factor of strength. Restated, the reduction factor of strength can be used to consider effect of the deterioration or corrosion in the strength or seismic capacity for a corroded RC column member. Therefore, this work can provide a preliminary seismic performance evaluation method for a corroded RC building structure. Additionally, for a corroded column member, its reduction factor of strength is determined based on the deterioration degree, which can be judged based on the visual inspection of deterioration following the technical textbook of the durability assessment of deteriorating RC building structures. Finally, taking an existing school building for an example, TEASPA which is established by NCREE is used to evaluate the seismic performance considering the corrosion and verify the application of the proposed preliminary seismic performance evaluation method for a corroded RC building structure.
標題以2018花蓮地震震害建物探討耐震初評方法之有效性
作者杜怡萱、葉桐
關鍵字震害,耐震評估,初步評估,鋼筋混凝土
摘要本研究蒐集2018年0206花蓮地震中12棟不同震害程度之建物資料,應用於三種國內現行耐震初步評估方法,以探討其有效性及合理性。三種耐震初評方法包括:鋼筋混凝土建築物耐震能力初步評估(PSERCB)、國家地震工程研究中心(NCREE)校舍耐震初評及街屋耐震快評;評估結果顯示,三種初評方法皆能大略篩選出耐震能力有疑慮之建物,各初評方法之評估結果與震害等級之相對關係亦大致符合,但皆呈現較保守之趨勢。各建物之三種初評結果大多相近,僅有二棟建物之NCREE街屋快評結果與另外兩種方法出現差異,且皆顯示PSERCB及NCREE校舍初評較NCREE街屋快評更為保守。
TitleVerification of Preliminary Seismic Evaluation Methods Using the Damaged Building Data of  2018 Hualien Earthquake
AuthorYi-Hsuan Tu and Tung Yeh
Keywordsearthquake damage, seismic evaluation, preliminary evaluation, reinforced concrete
AbstractData of thirteen buildings that damaged differently in the 2018 Hualien earthquake were collected and used to verify three preliminary seismic assessment methods. The three methods are all widely used in Taiwan, including the Preliminary Seismic Evalureliminary seismic evaluation of RC Buildings (PSERCB), the Preliminary Seismic Evaluation Method for Typical Building Structures of Primary and Secondary Schools by NCREE, and the Preliminary Seismic Evaluation Method for Typical Street-houses by NCREE. Comparison between the evaluation results and the observed damage states of the thirteen buildings showed that all three methods can identify the buildings that were heavily damaged. All three methods can sort the buildings in an approximately reasonable order. However, all three methods tended to give conservative results. The results from different methods for the same building were usually close. Only two buildings obtained different results between the NCREE method for street-houses and the other two methods. The PSERCB and the NCREE method for school buildings showed more conservative results than the NCREE method for street-houses in the two buildings.
標題具多重耐震性能等級之機率式結構耐震評估法
作者盧煉元、蕭輔沛、湯宇仕、黃尹男、陳慶輝、李官峰
關鍵字耐震評估、機率式評估法、多重性能等級、隔震結構、性能設計法、增量動力分析、非線性動力分析、非線性塑鉸
摘要現有耐震評估法大多僅能用於評估建物之抗倒塌耐震能力,因其損傷準則係依據結構瀕臨倒塌之行為為主。此種耐震評估法並不適用於評估重要之功能性建物(例如:醫院、高科技廠)或隔震結構,因為此類建物係以強震中必須保有其功能性為其耐震目標之一。有鑑於此,本文乃針對具高度耐震性能要求之重要建物與隔震結構研議一套可考量多種性能目標之機率式耐震評估法及流程,此法乃參採FEMA356與ASCE 41-13之建議將建物之耐震性能等級分為:立即可用(IO)、生命安全(LS)、倒塌避免(CP)。各性能等級之損傷準則分為整體損傷準則與局部損傷準則,前者採用FEMA 356及PEER-TBI之標準;而後者則參採ASCE41-13所建議之構件損傷準則。根據這些損傷準則與增量動力分析之結果,再據以建立不同性能等級之易損曲線作為耐震評估之依據。若為隔震結構,則新增隔震極限(IL)之性能等級,以便將隔震層之安全性納入耐震評估中,其損傷準則係以隔震支承位移超過隔震設計規範所訂定之最大總位移 為依據。本文以一幢耐震力不足之老舊建物為例,並採用滑動隔震技術對該建物進行耐震補強,再以所建議之多重性能耐震評估法,對隔震補強前後結構之耐震性能進行評估與比較,以量化隔震補強對於不同耐震性能等級之效益。評估結果顯示,原先倒塌風險極高之原始建物,經過隔震補強後,各性能等級之損傷機率指標皆明顯下降。因此,本文提出之機率式耐震評估法適用於隔震或固定基礎結構,可供工程界完整評估建物於不同耐震性能等級中之風險。
TitleAn approach for probabilistic seismic performance assessment of buildings considering multiple performance levels
AuthorLyan-Ywan Lu, Fu-Pei Hsiao,Yu-Shi Tang,Yin-Nan Huang,Ching-Huei Chen, Kuan Feng Lee
Keywordsseismic performance assessment, probabilistic assessment, multiple performance levels, isolated building, performance design, incremental dynamic analysis, nonlinear time history analysis, plastic hinge
Abstract Most of current seismic assessment methods for buildings aim to evaluate the collapse risk of buildings, since the damage criteria of these methods are associated with the mechanism of building collapse. These methods may not be suitable for the assessment of functional facilities or seismic isolated buildings, whose performance objective is usually required to maintain their functionality after a strong earthquake. For this reason, this study proposes an approachfor probabilistic seismic assessment of buildings considering multiple performance levels. This approach adopts the performance levels defined by FEMA 356 and ASCE 41-13, namely, immediate occupancy (IO), life safety (LS) and collapse prevention (CP). For each performance level, both global and local damage criteria are defined according to FEMA 356 and ASCE 41-13, respectively. Based on these damage criteria together with the result of incremental dynamic analysis, the fragility curves for each performance level can be established for seismic assessment. For buildings with isolators, a performance level called isolation limit (IL) is also considered, in order to include safety of the isolation system in the assessment procedure. The damage criterion for IL performance level is defined as when the isolator drift exceeds the maximum total isolator displacement   given in the current isolation design code of Taiwan. For demonstration of the proposed assessment method, a 5-story old apartment building was consideredas an example. The building was retrofitted by using sliding isolators, and the seismic performance of the building before and after the implementation of isolation was evaluated using the proposed method and the results were compared, so that the benefit of retrofitting can be quantified. Theassessment results show that the retrofit with the isolators greatly reduces the damage probabilities of the building at all performance levels. This demonstrates that the proposed method can be applied to evaluate seismic performance of either fixed-based or isolated building with consideration of multiple performance levels.
標題醫院消防撒水系統耐震性能補強評估
作者蔡詠安、林凡茹、柴駿甫、張國鎮
關鍵字消防撒水系統、易損性分析、數值分析、簡化評估、耐震補強
摘要

建築結構之耐震性能在長年的研究,相較早期之建築物已有明顯的提升,在受震後的主要災害與經濟損失往往不是建築結構造成,而是非結構系統之破壞造成。醫院內非結構設備中的消防撒水系統受中小地震後,若發生天花板遭撒水頭碰撞發生擴孔、粉塵掉落,或於大震中,撒水系統之支撐破壞,失去支承能力,可能造成醫院中斷醫療機能,甚至發生淹水、火災等自發性災害。因此消防撒水系統需以性能設計法進行耐震評估,若耐震容量不足則須加裝補強裝置。

本研究以台大雲林分院為案例醫院,依據甲仙地震後的破壞機制,提出消防撒水系統耐震詳細評估法以及適合業界應用之簡化評估流程,並參考NFPA13(National Fire Protection Association, 2010)補強之建議,提出四種補強方案,依據各方案之消防管線系統耐震性能表現建立易損性曲線,探討不同地震歷時之分析結果與適用性,並比較各方案之差異,以期做為消防管線系統耐震設計或補強之參考。

 
TitleSeismic evaluation and strengthening methods for fire protection sprinkler piping systems in hospitals
AuthorYung-An Tsai, Fan-Ru Lin, Juin-Fu Chai, Kuo-Chun Chang
KeywordsFire protection sprinkler system, fragility curve, numerical analysis, simplified assessment, seismic strengthening design
Abstract

In recent years, due to the vigorous development of performance design concepts, the seismic capacity of critical building structures (such as hospitals and high-tech factories) has been improved, and the major disasters and economic losses caused by the earthquake have changed from structural to non-structural systems, which include piping systems.

This study takes the medium-scale hospital in Southern Taiwan as an example to discuss the effects of installing strengthened elements on sprinkler piping systems which recommended by NFPA13. First, this research uses detailed analysis results to construct the fragility curves, and compares the fragility curves between before- and after-strengthened systems. Second, according to the dynamic characteristics of the sprinkler piping system, the simplified assessment method of original system and strengthened system are proposed in this study. It provides engineers with an alternative, rapid and approximate judgment in the seismic performances of piping systems based on in-situ observations and generic floor response spectrum.

  

第三十五卷第一期 (期別135) (109年)

第三十五卷第一期(期別135)(109年)

標題鋼筋混凝土構架填充高台度磚牆之反覆載重試驗
作者張順益、蘇柏翰、巫垂晃、婁光銘
關鍵字鋼筋混凝土、反覆載重試驗、側推分析、台度磚牆剪力強度
摘要台灣地區在夏天因氣溫高及濕度大,因而建築物的通風及採光就顯得非常重要,而為了能有較大的通風及採光面積,經常在窗台上方及兩邊柱間設置窗戶,因而出現了國內特有的台度磚牆,尤其是為了滿足儲藏室及廁所的隱密性更出現了高台度磚牆。國內對於台度磚牆的試驗研究相當稀少,應與缺乏大型實驗設備有關,近年台北科技大學已陸續進行相關的試驗研究,先後探討台度磚牆發生短柱破壞的臨界條件以及低台度磚牆剪力強度的反覆載重試驗研究,本文則進一步設計及製作兩座實尺寸鋼筋混凝土構架填充高台度磚牆試體進行反覆載重實驗研究,其填充台度磚牆高度分別為190公分與230公分。利用此兩座試體以及先前空構架試體的試驗結果來推估高台度磚牆的剪力強度計算公式。為了能可靠的預測高台度磚牆的剪力強度,計算公式除了考慮台度磚牆之高寬比對於剪力強度的影響之外,也納入紅磚劈裂強度對高台度磚牆剪力強度的貢獻。
TitleExperimental study of reinforced concrete frame filled with high masonry window spandrel
AuthorShuenn-Yih Chang, Bo-Han Su, Tsui-Huang Wu, Kuang-Ming Lou
Keywordsreinforced concrete building, highmasonry window spandrel, seismic evaluation, pushover analysis
AbstractTaiwan areais characterized by high temperature and high humidity in summer. Hence, light and air are important in designing a building. To permit light and air to enter, windows are designed as large as possible. As a result, a window is located below the RC concrete beam, above the masonry window spandrel and between the two adjacent RC columns. This type of window is very unique in Taiwan area. Furthermore, to meet the requirement of concealment for storage room or restroom, high masonry window spandrels appear. Experimental studies of this type of masonry window spandrels are very rare. This might be due to the lack of large laboratories for conducting prototype tests. In the recent, a series of experimental studies on this type of window spandrels have been conducted by National Taipei University of Technology. In fact, the critical condition to experience a short-column failure has been identified and the cyclic-loading test results for the reinforced concrete frame filled with low masonry window spandrelshas been completed and published. In this work, two reinforced concrete frames filled with low masonry window spandrels were designed and fabricated. A cyclically loading test was performed for each test specimen. A formula for estimating the shear strength of a masonry window spandrel was proposed.
標題包覆填充型箱型柱接力式繫筋對混凝土圍束的有效性
作者陳正誠 、吳品達、許瑜麟
關鍵字包覆填充型箱型柱、鋼骨鋼筋混凝土柱、填充型箱型柱、包覆型SRC柱、接力式繫筋
摘要包覆填充型箱型柱的橫向鋼筋,除了外圍之圍束箍筋外通常也需要配置繫筋以滿足規範之要求。但是傳統繫筋受到鋼骨箱型柱的阻撓而無法直通,因此箱型柱外側混凝土的圍束往往無法滿足規範的要求,使用「接力式繫筋」為可能解決這個問題的方法。接力式繫筋傳遞圍束力的路徑為「第1支短繫筋-橫向箱型柱柱板-縱向箱型柱柱板-另一橫向箱型柱柱板-第2 支短繫筋」。本文完成6組大尺寸(斷面尺寸550×550以上)包覆填充型箱型柱試體之反復側向載重試驗,探討接力式繫筋之有效性。試驗試體之寬厚比在27~37之間,因此下述結論適合使用於柱板寬厚比不大於37 之情況。試驗結果發現:(1)接力式繫筋可以取代直通式繫筋;(2)接力式繫筋可以有效圍束箱型柱外側之混凝土;(3)接力式繫筋對橫向鋼筋量之貢獻可以採用短繫筋之斷面積計算之。
TitleThe Effectiveness of Combined Ties on the Confinement of Encased Concrete-Filled Box Columns
AuthorCheng-Cheng Chen, Pin-Da Wu, Yu-Lin Hsu
KeywordsEncased Concrete-Filled Box Columns, steel reinforced concrete column, concrete filled box column, SRC column, encased box column, combined tie
AbstractIn an encased concrete-filled box column, the concrete inside the steel box column is confined by the box column. However, the confinement of the concrete outside the box column (referred as outer concrete hereafter) need to be provided by the steel cage which is composed of main reinforcement and transverse reinforcement. Due to the existence of the steel box column, the traditional ties used in RC columns can not be implemented here. The use of so called combined tie was introduce to solve this problem. The confinement force was transferred from the first short tie bar to the box column and then to the second short tie bar located at the opposite side of the box column. In this article, six large scale (column size larger than 550×550) was tested under cyclic lateral loading to investigate the effectiveness of using the combined tie.The range of the width-to-thickness ratio of steel plate investigated was between 27 and 37, therefore the test result was applicable to column with width-to-thickness ratio less than 37. Some conclusion can be drawn based on the test results: (1) the combined tie can substitute the use of conventional tie bar, (2) the combined tie is effective in confining the outer concrete, and (3) the confinement effect contributed by combined tie can be determined using the cross section of the short tie bar.
標題玻璃纖維包覆金屬螺紋管圍束混凝土之軸壓試驗與力學模型
作者李中生、周中哲、譚皓翔、陳威霖
關鍵字螺紋鋼管、玻璃纖維、圍束混凝土、軸壓試驗
摘要本文探討新發展之玻璃纖維包覆金屬螺紋鋼管圍束混凝土軸壓試驗結果與力學模型,此複合式圍束管的組成是以螺紋鋼管做為模具,於螺紋管外的凹槽中纏繞玻璃纖維紗束,形成環肋式加勁,再以預浸玻璃纖維布包覆加勁金屬螺紋管。本研究共進行36組圍束混凝土軸壓試驗,其中包含不同之圍束與斷面形式,目的為探討在不同圍束條件下之混凝土行為,以及混凝土圓柱中空斷面對於圍束效果的影響。本研究將中空斷面以面積比形式分成圍束與未圍束區域,利用試驗結果回歸出面積比與軸應變的關係式,利用所提出的面積比公式,可預測圍束中空混凝土圓柱的軸壓行為。
TitleAxial Behavior and Test of Concrete-Filled Spiral Corrugated Steel Tubes Wrapped with Glass Fiber Reinforced Polymer
AuthorChung-Sheng Lee, Chung-Che Chou, Hao-Hsiang Tan, V-Liam Chin
KeywordsSteel Corrugated Tube, Glass Fiber Reinforced Polymer (GFRP), Confined Concrete, Axial Compression
AbstractThis paper presents the axial behavior of concrete cylinders confined by a novel composite tube. This composite tube consists of a spiral corrugated steel tube and Glass Fiber Reinforced Polymer (GFRP) shell. The spiral corrugated steel tube serves as a mold for wrapping GFRP shell. The concave area of spiral corrugated tube are filled with pre-preg fiber strands and epoxy resins to form an enhanced flat tube, and a multilayer GFRP jacket are wrapped around the enhanced steel tube. Thirty-six cylinder specimens were designed and tested under uniaxial compression. The test parameters included different types of confinement tube and cross section. This paper proposes an analytical method to predict the axial behavior of concrete filled GFRP-wrapped spiral corrugated tube, and a calculation method for the ratio of effective confined area to predict the axial behavior of hollow section specimens.
標題利用虛擬側力與破壞機制探討挫屈束制支撐面外穩定性及案例評估分析
作者歐易佳、陳力維、蔡青宜、吳安傑、蔡克銓
關鍵字挫屈束制支撐、撓曲效應、面外穩定性、虛擬側向力、破壞機制、二次效應
摘要當BRB或端部接合發生面外不穩定時,其軸向勁度與強度將大幅降低,喪失消散能量之功能。本研究提出一套穩定性評估模型,考慮圍束單元撓曲效應及接合板旋轉效應,並利用虛擬側向力及破壞機制探討BRB及接合之面外穩定性。為驗證所提方法之有效性,本研究設計六組不同長度、外管尺寸及接合板勁度之實尺寸WES-BRB進行於不同初始缺陷及端部面外位移下之反覆載重試驗。試驗結果顯示,分析模型可確實反應初始缺陷、端部面外位移及接合板勁度效應對BRB整體穩定性之影響。本文另利用該評估模型對業界常用之BRB設計強度、構架尺寸與配置型式,以國震中心BOD雲端設計軟體規劃的581組BRB設計例進行挫屈強度分析。分析結果顯示,當BRB端部面外位移角由1%增至2%時,挫屈強度減損幅度約介於12%至15%,對整體穩定性影響非常顯著;若接合板緣無加勁,其挫屈強度較有加勁時減少約5%至20%,顯見工程應用時接合板加勁之重要性。案例分析亦顯示,外鋼管設計之需求容量比若控制在0.9以下,可使其面外穩定性更有保障。
TitleBuckling-Restrained Brace Out-of-Plane StabilityAssessment Using Notional Load and Failure Mechanism Analysis with Multi-Case Study
AuthorI-Chia Ou, Li-Wei Chen, Ching-Yu Tsai, An-Chien Wu, Keh-Chyuan Tsai
Keywordsbuckling-restrained brace, flexural effect, out-of-plane stability, notional load, failure mechanism, second-order effects
AbstractWhen the out-of-plane (OOP) instability of the BRB and the end gusset connections occurs, the energy dissipation capability of the BRB will be significantly reduced. This study develops a simplified analytical model using the concept of the notional load and considering the flexural restrainer to assess the BRB global stability. Cyclic loading tests on six full-scale BRBs with different lengths, steel casing sizes, and gusset connection stiffness were conducted under various initial imperfections and OOP drifts to demonstrate the effectiveness of the proposed method. Test results indicate that the effects of the initial imperfection, OOP drift, and gusset edge stiffener on the BRB stability are reasonably captured. Moreover, parametric analyses were conducted using the proposed method on 581 BRB and connection cases, detail designed by the Brace-on-Demand cloud service, with varying frame span-to-height ratios and brace yield strengths. Analytical results suggest that the stability limit strength is reduced by 12% to 15% with the OOP drift ratio increased from 1% to 2%,while it is reduced by 5% to 20% without the presence of gusset edge stiffeners.It is concluded that the global stability is vulnerable to the OOP drift and adequately stiffening the gusset is recommended in BRB practices. It also shows that as long as the demand-to-capacity ratio (DCR) is less than 0.9 for steel casing stability calculated by using the practical evaluation method, the overall stability can be effectively conserved.

第三十四卷第二期 (期別134) (108年)

第三十四卷第二期 (期別134) (108年)

標題輕型鋼管結構簡易接頭之受力行為與強度
作者陳正誠、林曉芳
關鍵字鋼管結構接頭、簡易接頭
摘要近年來臺灣因為少子化的問題,勞動市場逐漸邁向高齡化,勞力的缺乏以及營造業基層勞動人力招募不易等因素,使得需要高勞力的鋼筋混凝土構造建造成本持續提升。使用輕型鋼管結構配合新型式簡易接頭的施工方法,是一個可以有效降低勞力需求及建造時間的結構形式。但目前對於簡易接頭之強度以及與簡易接頭連接之銲道的強度,沒有相關研究結果可供參考。有鑑於此,本文採用結構試驗之方式,探討簡易接頭受力行為,建立接頭強度評估方法。每一個簡易接頭是由兩個形狀構造相同的接頭元件,配合兩顆高強度螺栓組合而成。簡易接頭有用於梁端接頭(簡稱BJ)及用於柱端接頭(簡稱CJ)兩種型式,目前適合使用於斷面100 x 100 mm 之方管及200 x 100 mm之矩形管。經過一系列共51 個試體之載重試驗,配合規範相關強度評估公式,得到主要結果如下:(1)與200 x 100 mm 矩形管連接之BJ 接頭,其正向剪力設計強度可達22.5 tf,負向剪力設計強度可達12.3 tf;(2)與100 x 100 mm 方管連接之BJ 接頭,其正向剪力設計強度可達10.7 tf,負向剪力設計強度可達9.98 tf;(3)與200 x 100 mm 矩形管連接之CJ 接頭,其拉力設計強度可達13.8 tf,壓力設計強度可達61.4 tf;(4)與100 x 100 mm 方管連接之CJ 接頭,其拉力設計強度可達13.8 tf;壓力設計強度可達37.0 tf。
TitleThe Strength of A New Type Connection for Rectangular Steel Tube Structures
AuthorCheng-Cheng Chen, Xiao-Fang Lin
Keywordssteel tube structure, steel tube construction
AbstractIn order to improve construction efficiency of low-rise buildings, a new type of connection for steel tube structures was developed.The new type connection for horizontal and vertical members are designated as BJ and CJ connections, respectively. Each of the new type connection is composed of two identical parts and assembled by two high strength bolts. The strength of this new type connection and the strength of the welds connecting the connection and steel tube were experimentally studied. A total of 51 successful tests were carried out and the following conclusions then are made accordinly: (1) The welds connecting the new type connection and the steel tube possess enough strength to transfer member forces from tubes to the connection. Therefore, it is suggested that the type and size of welds used in the test specimen should be used in the real structures. (2) The design shear strengths for BJ connection are proposed. (3) The design tensile strength and design compressive strength for CJ connection are also proposed.
標題2018 年CNS 560 鋼筋標準修訂
作者林克強
關鍵字竹節鋼筋、螺紋節鋼筋、節相對投影面積,總伸長率、均勻伸長率
摘要本文主要介紹並說明2018 年CNS 560「鋼筋混凝土用鋼筋」標準的主要修訂內容,包括:(1)新增SD 550W 與SD690 之鋼筋種類:SD 550W 之鋼筋屬於「耐震構材用」與「可銲接」鋼筋;SD 690 為一般用途之鋼筋,若欲應用於耐震構材,可要求實際抗拉強度與實際降伏強度比值不小於1.25,但因該鋼筋未明確規定化學成分,故須經驗證合格之銲接程序方可銲接加工,否則不可銲接。(2)新增螺紋節形式之鋼筋:螺紋節鋼筋可適用於灌漿式螺紋續接器,惟螺紋節鋼筋之節距最大值不大於鋼筋半徑,可獲得與竹節鋼筋相同之握裹性能,並可視為竹節鋼筋之一種。(3)修訂彎曲試驗法:依據ASTM A615 與A706 標準之精神,進行彎曲試驗時,鋼筋端部之軸向不得固定,以避免鋼筋在彎曲過程中受到額外軸向應力之影響。此外,建議未來的CNS 560 鋼筋標準能以對應於實際抗拉強度(actual tensile strength)之均勻伸長率(uniform elongation),作為鋼筋韌性變形能力的評估準則,使得鋼筋能符合結構性能設計原理,提供結構構件對應的變形需求。
TitleRevisions of CNS 560 Steel Bars Standard in 2018
AuthorKer-Chun Lin
Keywordsdeformed bars, threaded bars, relative projected area of rib, total elongation, uniform elongation
AbstractThis paper is intended to introduce and describe the major revisions of CNS 560 standard for steel bars using in reinforced concrete structures that include: (1) Adding two types of steel grade, SD 550W and SD 690. For the SD 550W steel, it is weldable and applicable for seismic members. For the SD 690 normal steel, a minimum ratio of 1.25 for the actual tensile-to-yield strength ratio is requested for seismic members, but welding is not allowed due to no limitations on its chemical compositions. (2) Creating a new type of threaded bars. The threaded bars are suitable for the grouted and threaded couplers. The requirements of deformation dimensions for the threaded bars are identical to those for the deformed bars, except that the rib pitch shall not exceed 0.5 times the diameter of steel bar. That is to get the same level of bond performance with the deformed bars. Therefore, the threaded bars can be regarded as one kind of the deformed bars. (3) Revising the method of bend test. For the bend test, based on the requirements of ASTM A615 or A706 standard, the steel bar shall not be restricted movement in its longitudinal direction to prevent from effects of the additional axial stress during the bend testing. In addition, it is recommended that the requirements of uniform elongation corresponding to actual tensile strength should be incorporated into the future version of CNS 560 standard as an assessment criterion of steel bar ductility. This conforms to the principles of performance-based design and provide the corresponding deformation demands of structural members.
標題板橋浮洲鋼筋混凝土高層建築結構補強實驗及ETABS非線性動力耐震評估
作者周中哲、鍾秉庭、粘評、陳威霖、劉郁芳、柯鎮洋、王志誠、陳景誠
關鍵字鋼筋混凝土高層建築、單側增築RC 梁、單側鋼板剪力補強、雙K型斜撐鋼框架剪力補強、U型鋼板剪力補強、耐震試驗、非線性靜力側推分析、非線性動力歷時分析
摘要本研究評估新北市板橋浮洲37棟鋼筋混凝土高樓層住宅的結構補強效益,內容先敘述補強構件的試驗,驗證補強設計的合理性,再藉由結構分析程式 ETABS(2016)進行其中一棟高層建築物的非線性靜力側推及非線性動力歷時分析求得耐震需求來評估補強效益。板橋浮洲建築物地上結構之補強構件共進行二種類型試驗:(1) 鋼筋混凝土連梁剪力補強試驗,主要探討以單側增築梁寬(增加箍筋量及無收縮水泥砂漿填補)和單側補鋼板對鋼筋混凝土梁剪力補強效益,(2)雙K 型斜撐鋼框架剪力補強試驗,主要探討鋼造雙K 型斜撐於反覆載重下之挫屈及與既有RC 結構接合行為。建築物地下結構之補強構件則進行鋼板剪力補強鋼筋混凝土梁試驗,探討兩側鋼板和U 型鋼板補強對鋼筋混凝土梁剪力補強成效。上述實尺寸構件補強試驗於2016~2017 年間在國家地震工程研究中心進行,補強試驗結果可滿足臺灣和美國規範ACI 374.2R-13(2013)之強度與韌性要求。本研究並進一步地以一棟24 層高樓鋼筋混凝土建築物作為分析標的,藉由非線性靜力側推及非線性動力歷時分析瞭解建築物於475及2500 年地震迴歸期下的變形及力量需求,驗證耐震補強成果。
TitleSeismic retrofit of existing high-rise RC buildings: full-scale test and nonlinear dynamic frame analysis using ETABS program
AuthorChung-Che Chou, Ping-Ting Chung, Ping Nian, V-Liam Chin, Yu-Fang Liu, Chen-Yang Ko, Chu-Chun Wang, Ching-Cheng Chen
Keywordshigh-rise RC building, shear retrofit, double K-braced steel frame, U-shaped steel plate, one-sided steel plate, seismic test, nonlinear static pushover analysis, nonlinear dynamic frame analysis
AbstractThis study evaluates the seismic retrofit of existing high-rise RC buildings in New Taipei City, Taiwan. The paper presents structural test results for verifying the design of member retrofit, nonlinear static pushover analysis and dynamic analysis of the high-rise RC building. The superstructure is mainly retrofitted by two methods. One way adopts a one-sided shear retrofit scheme for RC coupling beams, which are retrofitted with reinforced cement mortar or a steel side plate, respectively, from only one side of the beam to simulate the actual condition on site. The other way is to add a double K-type braced steel frame to increase the shear capacity of the RC frame. The RC beams in the basement are retrofitted with steel plates to increase the shear capacity. The full-scare members with shear retrofits were tested at the National Center of Research on Earthquake Engineering (NCREE) in 2016 and 2017. The test results meet the requirements of the strength and ductility based on Taiwan Seismic Specification and ACI 374.2R-13 (2013). In this study, a 24-story high-rise RC building was analyzed using the computer program, ETABS (2016). The nonlinear static pushover analysis and nonlinear dynamic analysis were conducted to evaluate the seismic performance of the building frame under a set of 2500 year-return period earthquakes, further verifying the seismic demands and technology of the seismic retrofit.
標題台灣混凝土彈性模數折減對數項結構相關設計規範的影響
作者胡瑋秀、廖文正
關鍵字彈性模數、台灣混凝土結構設計規範、台灣建築物耐震設計規範及解說、鋼結構容許應力設計法規範
摘要台灣混凝土彈性模數Ec 較現行規範所預估之値有偏低的趨勢,其值約為規範的80%左右,彈性模數的修正將會對版梁柱尺寸設計、設計基底剪力值和其餘與彈性模數相關的規範產生影響,如台灣混凝土結構設計規範、台灣建築物耐震設計規範及解說與鋼結構容許應力設計法規範等。然而上述相關規範沒有對其中受彈性模數影響的公式做出修改。為使設計更為準確,須探討彈性模數修正對規範的影響。本研究檢視前述規範中直接或間接與彈性模數有關的規定,探討其數項受影響的公式,並依據學理提出對應的建議。依據本研究結果,非預力單雙向版規範因應彈性模數的折減,其最小深度需要增加為1.077 倍;在柱的長細效應中,當細長比為40時,其彎矩放大係數則需要增加為1.15倍;當混凝土之抗壓強度小於360kgf / cm2 時,則單一剪力釘容許強度將變為0.89倍,所需剪力釘個數變為1.124倍。以上結果顯示,彈性模數的修正不僅單是修正Ec 值公式,規範中直接或間接與彈性模數有關的規定均須要修正。
TitleStudy of Influences of Reduced Elastic Modulus of Concrete on Related Structural Design Codes in Taiwan
AuthorWei-Hsiu Hu, Wen-Cheng Liao
Keywordsmodulus of elasticity, design code for structural concrete in Taiwan
AbstractIn Taiwan, the prediction of Ec calculated by current design code is usually overestimated by 20% of that obtained by experimental results. The revision code of Ec = 12000 (f’c)^0.5 is 80% of current Ec = 15000 (f′c)^0.5 . The reduction of Ec would influent the size of beam and column, design value of base shear and other related structural design codes in Taiwan, such as “Design Code for Concrete Structures”, “Seismic Design Specifications and Commentary of Buildings” and “Allowable Stress Design Specifications and Commentary of Steel Structures”. The objectives of this research are to clarify those influences on these related structural design codes with reduced Ec and to comment and give suggestions to the engineering society. The results show that because of the reduction of Ec, the minimum thickness of reinforced concrete slab should increase by 7.7% times, moment magnification factor would increase by 1.15 times (if slenderness ratio of column is 40), number of shear concrete stud would increase by 1.124 times (if compressive strength of concrete f′c < 360 kgf/cm^2). Structural design codes that directly or indirectly related to Ec should be modified accordingly because of the reduction of Ec.
標題初談浮動式房屋分析與設計
作者王峙蓉、尹世洵、張哲豪
關鍵字抗洪房屋、浮動式房屋
摘要本文的目的主要是介紹設計浮動式房屋時所需考慮的設計概念與流程。此具有抗洪能力之浮動式房屋由避淹鋼箱下部結構與輕型冷軋型鋼桁架上部結構所組成,並在房屋周圍設置引導房屋垂直運動之柱子,當洪水來臨時,利用洪水的浮力讓房屋沿著周圍柱子往上浮起,當洪水退去時,沿著周圍柱子下降至地面。由於房屋具有上浮的功能,所以無法直接固定於地面,因此藉由支承墊傳遞垂直向與水平向載重。本文將藉由一個浮動式房屋案例,針對浮動式房屋四個主要組成部分,包括避免洪水進入屋內的避淹鋼箱、屬於房屋主體的輕型鋼桁架結構、房屋未浮起時將房屋所受載重傳遞至基礎的支承墊、以及房屋浮起時限制房屋水平移動的導柱,進行實際案例分析與設計,希望所介紹之浮動式房屋設計流程與分析方法可以提供國內產官學界參考,對國內浮動式房屋的發展有所幫助。
TitlePreliminary discussions on analysis and design of floating houses
AuthorJhih-Rong Wang, Shih-Hsun Yin, Che-Hao Chang
Keywordsflood-proof house, floating house
AbstractThe main purpose of this paper is to introduce the concept and procedure needed to design a floating house which has flood-proof capability. The house was composed of steel box substructure and lightweight cold-form steel truss superstructure. Several columns were built up around the house, which can guide the house move up and down through a ring system connected to it. The house can float up along the columns due to buoyancy when flood waters invade and return back to the original location of the base when flood waters recede. Since the house has such a floating mechanism, it cannot be fixed to ground directly. Rubber Bearings were needed to pass vertical and horizontal loadings. In this paper, a real case study will be conducted for designing a floating house including a steel box structure preventing from invasion of flood waters, a lightweight truss structure forming the main house structure, rubber bearing pads transferring loads to foundation when the house is located on the ground, and guide columns limiting the horizontal movement of the house when it floats. The design and analysis procedure presented here may provide industry, government, and academic institutions in Taiwan with some design guidance and be beneficial to the development of floating houses.

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第三十四卷第一期 (期別133) (108年)

第三十四卷第一期 (期別133) (108年)

標題雙向鋼板剪力牆邊界梁柱耐震設計與分析研究
作者楊依璇、黃彤、李昭賢、蔡青宜、蔡克銓
關鍵字三維鋼板剪力牆、邊界柱、容量設計、軸彎剪互制、有限元素模型分析、合成梁
摘要針對雙向鋼板剪力牆底層角落邊界柱須抵抗兩正交向剪力牆之作用,本研究利用過去研究所提單向剪力牆底層邊界柱設計方法,考量雙向構架及鋼板共同造成之彎矩、剪力及軸力互制關係,設定底層柱塑鉸高程在0.3倍柱高,提出雙向鋼板剪力牆邊界柱設計方法。為驗證所提之設計方法,本研究利用四組兩層L 型平面之雙向鋼板剪力牆有限元素模型進行分析,分析結果顯示,所提設計方法可準確預測底層受壓邊界柱之雙向彎矩需求分佈與塑鉸發生位置。此外箱型邊界柱須承受與柱面垂直之鋼板拉力場作用力,柱面板厚不足時可能導致局部非線性變形,本研究亦探討雙向鋼板剪力牆交界處邊界箱型柱面外受拉力與變形之關係,並提出耐震設計方法。鋼板剪力牆頂層邊界梁構件須承受下方鋼板下拉力引致之正彎矩,本研究以有限元素分析探討邊界鋼寬翼梁與混凝土樓板合成之行為,分析結果顯示當合成梁受來自鋼梁下方之鋼板拉力,混凝土樓板與鋼梁之共同作用行為並不明顯,因此本研究建議設計時應保持一般鋼寬翼斷面梁之設計方法,僅考量鋼骨之彎矩強度。
TitleSeismic design and analysis on boundary elements in bidirectional steel plate shear walls
AuthorYi-Hsuan Yang, Tung Huang, Chao-Hsien Li, Ching-Yi Tsai, Keh-Chyuan Tsai
Keywordsbi-directional steel plate shear walls, capacity design, axial, shear and flexural interaction, finite element model analysis, composite beam
AbstractThe aim of this research is to propose a seismic design method for the corner vertical boundary elements (VBEs) in bidirectional steel plate shear walls (SPSWs) through a series of analytical and experimental studies. The VBEs at the intersection of bidirectional SPSWs must sustain the force demands induced from the two SPSWs simultaneously. The column axial force, bi-directional moments and shears are incorporated in the proposed procedures in computing the reduced column flexural capacities. The location of the bottom column flexural hinge is set at an elevation of 0.3 times the first story column height in order to achieve both performance and economy goals. In this paper, the effectiveness of the proposed design method is verified by four two-story L-shape bidirectional SPSW finite element model (FEM) analyses. The pushover analyses on the FEMs confirm that the flexural demands and the plastic hinge locations of the bottom corner VBEs can be predicted by the proposed method. This research also investigates the effectiveness of the composite action of the concrete slab and steel beam in the SPSW’s top boundary element using FEM analysis. Analysis results show that the composite action is not pronounced since the vertical downward panel forces are applied on the beam bottom flange.
標題 含鋼板阻尼器構架最佳化設計
作者 張舉虹、蔡克銓
關鍵字 鋼板阻尼器、耐震設計、容量設計、受剪挫屈、最佳化設計、抗彎構架
摘要 鋼板阻尼器(Steel Panel Damper, SPD)為三段式寬翼構件,中段為非彈性核心段,上下兩段為彈性連接段,在核心段配置加勁板,可延遲受剪挫屈的發生。在抗彎構架配置SPD,核心段腹板能反覆受剪降伏來消能,本研究利用MATLAB 最佳化工具箱,結合模擬退火法與梯度下降法成混合式演算法,考慮上下層SPD 相同且皆於梁跨中心,僅探討SPD、邊界梁與其交會區之設計,以最少SPD、加勁板、邊界梁全長、交會區疊合板與連續板總用鋼量為目標函數。SPD、加勁板、邊界梁斷面與交會區疊合板厚為設計變數;以滿足SPD、邊界梁與交會區容量設計、SPD 核心段加勁板設計及防止斷面局部與側向扭轉挫屈作為基本限制條件,研究最少用鋼量為「基本設計」。因SPD 勁度強度可分離,在固定強度下可增加勁度,然增加SPD或邊界梁勁度,皆能提升構架勁度,本研究根據反曲點取出SPD 與邊界梁十字子構架,在選定SPD 強度下,以子構架側向勁度增加50%為新增限制條件,再次進行最佳化設計,稱所得最少用鋼量為「1.5 倍勁度設計」。設計範例顯示在滿足基本限制條件下,只須增約9%用鋼量,即可達1.5 倍勁度設計。為提高勁度,主要以增加邊界梁深與腹板厚較有效,但將導致梁強度增加40%。另對梁強度增量設25%上限,發現須較基本設計增約11%用鋼量,才可得1.5 倍勁度設計。若另對梁深也設上限,須增約30%用鋼量,才可得1.5 倍勁度設計;此時梁強度為基本設計的1.2 倍。本研究也討論垂直載重對邊界梁設計之效應,並表列實際可供工程應用之最佳化SPD 與邊界梁的設計尺寸案例。
Title Optimization of Steel Panel Dampers for Moment Resisting Frame Designs
Author Chu-Hung Chang, Keh-Chyuan Tsai
Keywords steel panel damper, seismic design, capacity design, shear buckling, optimization design, moment resisting frame
Abstract The proposed 3-segment steel panel damper (SPD) consists of one middle inelastic core (IC) and two end elastic joint (EJ) wide-flange sections. During earthquakes, the two EJs of the same cross-sectional property, are designed to remain elastic while the IC could undergo large inelastic shear deformation thereby dissipating seismic energy. In order to sustain a large deformation and delay the shear buckling of the IC web, stiffeners must be properly devised. In this study, optimization algorithm is adopted to proportion the SPDs and the boundary beams, and achieve the minimum steel weight design. It is assumed that two identical SPDs, one above and one below, are attached to the boundary beam mid-span. The MATLAB optimization toolbox combined the simulated annealing algorithm with the gradient-descent method is adopted to find the minimum steel weight design. The objective function is the total weight of the SPD, the boundary beam and the panel zone. The design variables are the sectional properties of the SPD, the boundary beam and the doubler plate thickness. Constraints include the capacity design of the SPD, boundary beam and panel zone, the stiffeners of the IC web, compact section and lateral torsional buckling limit state design requirements. The ”basic design”  is the lightest sections meeting all the constraints. The lateral stiffness of the two SPDs- to-boundary beam subassembly can be enhanced by either increasing the stiffness of the SPDs or the boundary beam. As examples, the optimization designs of increasing 50% more stiffness of the subassemblies as the new constraint were conducted also. While complying with the aforementioned constraints, the steel weight is increased by about 9% to achieve a 50% more stiffened design. The stiffness of the subassemblies are found enhanced most effectively by increasing the beam depths and web thicknesses.
標題 鋼造自復位挫屈束制斜撐(SC-SBRB)發展及耐震試驗
作者 周中哲、蔡文璟、鍾秉庭
關鍵字 自復位挫屈束制斜撐、反覆載重、殘餘變形、能量消散
摘要 鋼造斜撐構架具有良好的耐震性能,然而在大變形下易使建築物產生結構損壞和殘餘變形,造成震後難以修復且費用昂貴,因此本文提出一種可提升建築物抗震能力的全新鋼造自復位挫屈束制斜撐(Self-Centering Sandwiched Buckling-Restrained Brace, SC-SBRB),此種斜撐同時具有雙核心自復位斜撐的自復位能力及挫屈束制斜撐的消能能力,自復位能力是利用斜撐中的兩組拉力構件束制斜撐中的鋼受壓構件,使斜撐在大變形下具有回到零殘餘變形的能力;消能能力是利用兩組獨立分離的圍束構件以栓接方式束制斜撐中的核心構件,使得斜撐受壓不會挫屈而產生飽滿的遲滯消能。本文首先介紹兩組不同構件配置的自復位挫屈束制斜撐,說明其力學行為及抗震機制,以減少建築物受震的最大變形及殘餘變形,並於實驗室進行兩組長度7860 mm 的實尺寸斜撐試驗驗證其耐震性能,試驗結果顯示斜撐的傳力機制與理論預測相符,試驗亦證明兩組斜撐試體分別經歷共3 次反覆載重及52 圈疲勞載重測試下仍保持良好耐震能力,斜撐更可在層間側位移角2.5%而不破壞,最大軸力可達1700 kN,全部試驗的累積韌性容量可達1090-1129,超過美國耐震規範AISC (2010)的建議值200。
Title Development and Seismic Tests of Steel Self-Centering Sandwiched Buckling-Restrained Braces (SC-SBRBs)
Author Chung-Che Chou, Wen-Jing Tsai, Ping-Ting Chung
Keywords Self-centering sandwiched buckling-restrained brace (SC-SBRB), Cyclic test, Residual deformation, Energy dissipation
Abstract Earthquake-resisting frame systems that are designed based on current seismic provisions provide life safety performance in a large earthquake, but may have significant structural damage or residual drift due to energy dissipation in designated structural members. The damage leads to difficult or expensive repairs after a large earthquake. Therefore, development of a structural system that has both energy dissipation and self-centering properties in earthquakes is needed to improve the seismic performances of buildings. This paper presents a viable solution that was validated by multiple cyclic tests of an innovative brace, called a dual-core self-centering sandwiched buckling-restrained brace (SC-SBRB). The proposed brace combines the self-centering property of a dual-core self-centering brace (DC-SCB) and the energy dissipation of a sandwiched buckling-restrained brace (SBRB) together. The dual-core SC-SBRB is essentially a DC-SCB that is positioned concentrically with a SBRB to create both the self-centering and energy dissipation properties in either tension or compression. A 7860 mm-long dual-core SCSBRB, which uses ASTM A572 Gr. 50 steel as bracing members and ASTM A416 Grade 270 steel tendons as tensioning elements, was cyclically tested six times to validate its kinematics and cyclic performance. The test program demonstrated that the proposed dual-core SC-SBRB provides stable hysteretic responses with appreciable energy dissipation, self-centering behavior and large deformation capacity before low-cycle fatigue failure of the SBRB core.
標題 考量強地動特性之可變勁度隔震系統研發與應用
作者 劉政嘉、林子剛、盧煉元、蕭迦恩
關鍵字 勁度可變、速度能量、隔震系統、半主動控制、半主動控制、最佳動位能比例法
摘要 近年來,結構物隔減震研究日趨受到重視,過去的研究顯示隔減震效應無法即時判定地震類型,並針對近遠域地震特性改變以達到最佳控制效果。為了使控制效果最佳化,本研究開發一套半主動控制系統「地震能量預測比例法」(Feed-forward Predictive Earthquake Energy Analysis, FPEEA),透過量測地震主波到來前之速度,計算頻率域之能量頻譜,進而區分出近遠域地震;並結合最佳動位能比例法(Minimal Energy Weighting, MEW)決定位能權重,以有效即時控制結構反應。本研究已開發完成此半主動控制理論, 搭配槓桿式可變勁度隔震系統(Leverage-type Stiffness Controllable Isolation System, LSCIS),調整槓桿支點位置進而改變隔震層勁度,以達到最佳的隔減震效果。與過去的半主動控制律相比,本研究之控制律可達到與MEW相同之控制效果甚至更佳。實際振動台試驗結果顯示,透過速度能量判定可於主要震波來前區分出近遠域地震,達到即時控制效果。而針對近域地震情況下,更可有效降低隔震層位移,並對上部結構加速度反應有良好的控制成效。
Title Development and Application of a Variable Stiffness Isolation System Considering Ground Motion Characteristic
Author Zheng-Jia Liu, Chia-En Hsiao, Tzu-Kang Lin, Lyan-Ywan Lu
Keywords Stiffness-variable, energy of velocity, isolation system, semi-active control, minimum energy weighting
Abstract In recent years, the research of isolation and mitigation system has become more and more important. In the traditional isolation and mitigation system, the control effect may be reduced because of unknown earthquake types. To have the best effect of response reduction, the systems have to be adaptive with the earthquake type. To achieve that, an upgraded algorithm, Feed-forward Predictive Earthquake Energy Analysis (FPEEA), is proposed by considering the energy of earthquake velocity to have the optimal response. The new algorithm quickly evaluates the velocity energy to have the optimal weighting of minimum energy weighting (MEW). With the optimal weighting of the potential energy and the kinetic energy, the PFEEA can reduce the structural responses efficiently. In order to demonstrate the performance of the proposed algorithm, a single-degree-of-freedom structure is used as a benchmark in both numerical simulation and experimental verification. With predicting the optimal weighting in advance, the type of earthquake can be defined before the main shock of earthquake comes. The results have shown that the dynamic response of the structure can be effectively alleviated. Comparing to the structural responses of the MEW method, the performance of the proposed algorithm is similar to MEW or even better. The shaking table test also demonstrates the feasibility of applying the proposed algorithm in practical application.
標題生命週期考量之鋼管混凝土建築結構合理設計分析法
作者陳振川、吳子良
關鍵字潛變、自體收縮、乾燥潛變、鋼管混凝土、結構設計
摘要鋼管混凝土建築結構已經成為一種常用之建築型式,其搭配自充填混凝土之內填,對於增加高層建築物之承載及勁度均有助益,並增加建築面積之有效使用。然而,現有規範及設計採用複合材料設計方式,其結構設計和所充填混凝土之潛變收縮行為及混凝土與鋼材之互制現象,則未在現有建築工程設計充分考量。本研究介紹混凝土時間變形特性及應用本土潛變預測之必要性,並提出一從生命週期考量之鋼管混凝土建築結構設計分析法,並提出設計程序與案例分析,以確保在生命週期之使用年壽期間,結構物可提供長期結構安全及服務性。
TitleA Life Cycle Consideration Structural Design Method for Concrete-Filled Steel Tubes Structure
AuthorJenn-Chuan Chern, Zu-Liang Wu
Keywordscreep, autogenous shrinkage, drying creep, CFT, structural design
AbstractThe concrete-filled steel tubular structure has become a common structural type for buildings, which is matched with the use of self-compacting concrete, which is helpful for increasing the bearing capacity and stiffness of the high-rise building and increasing the effective use of the building area. However, the existing specifications and designs adopt the composite design method, and the structural design and the creep & Shrinkage behavior of the in-filled concrete and the interaction between concrete and steel tube are not fully considered in the existing structural design. This study introduces the time-dependent deformation characteristics of concrete and the necessity of applying local developed prediction formulas and proposes a design analysis method for concrete-filled steel tubular structures considering life cycle, and proposes design procedures and case studies to ensure the life expectancy in life cycle. During the period, the structural safety and serviceability of the structure can be ensured.

第三十三卷第四期 (期別132) (107年)

第三十三卷第四期 (期別132) (107年)

標題強脊結構系統之耐震行為研究
作者郭銘桂、林瑞良、蔡克銓
關鍵字層間位移角、廣義建築模型、強脊系統、非線性反應歷時分析
摘要為解決結構受震層間位移角分佈不均之問題,本研究希望利用簡化分析模型對強脊系統(strongback system)進行大量的參數分析,提出有效的設計參數。本研究以廣義建築模型(generalized building model,GBM)及含強脊系統之廣義建築模型(generalized building model with strongback,GBMSB)作為簡化的數值模型,針對在台北二區,第二類地盤的三、六、九和二十層建築進行參數分析。採用SRSS 振態疊加法估算最大彈性層間位移角,並利用層間位移角的標準偏差作為均勻度指標,評估層間位移角分佈之均勻性,使層間位移角的標準偏差為最小之設計為最佳設計。分析結果顯示強脊系統為純剪力型式,且其層勁度呈線性遞減,並且於一樓加勁的勁度分配法效果最佳。為了驗證參數分析之有效性,採用SAC 研究計畫中的九層鋼構造抗彎矩構架,和國家地震工程研究中心台南實驗室的三層鋼筋混凝土構架試體作為驗證例。將原始結構模型(分別稱為SAC9 和T3)、含最佳強脊系統之結構模型(分別稱為SAC9-SB 和T3-SB)、及含非最佳強脊系統之結構模型,分別利用PISA3D 結構分析程式進行非線性反應歷時分析。結果顯示配置最佳強脊系統之SAC9-SB 和T3-SB 層間位移角之標準偏差平均值最小,能使層間位移角分佈最為均勻。
TitleStrongback systems for enhancing the seismic performance of buildings
AuthorMeng-Kwee Kek, Jui-Liang Lin, Keh-Chyuan Tsai
Keywordsinter-story drift ratio, generalized building model, strongback, nonlinear response history analysis
AbstractIn order to reduce the variations of peak inter-story drifts occurred in earthquakes along the building height, this research conducts the parametric study of the buildings with strongback systems through simplified numerical models. The generalized building model (GBM) and generalized building model with strongback (GBMSB) are employed as the simplified numerical models in the parametric study. This study investigated 3, 6, 9 and 20-story buildings.The peak inter-story drift ratios along the building height are computed by using the response spectrum analysis method, in which the peak modal responses are combined according to the SRSS method. The optimization objective is to minimize the standard deviation of the peak inter-story drift ratios. The optimal stiffness distribution of a strongback is thus obtained.The results of parametric study show that when a pure shear-type strongback, whose first story is stiffened and its story stiffness decreases linearly along the height, the standard deviation of inter-story drifts is minimized. The effectiveness of the proposed method is verified by investigating one 9-story steel building and one 3-story reinforced concrete (RC) building.The 9-story steel moment resisting frame, designated as SAC9, was a prototype building located in Los Angeles adopted in SAC steel research project. In addition, the 3-story RC building, designated as T3,was tested using shaking table at Tainan Laboratory of National Center for Research on Earthquake Engineering. The optimal designs of SAC9 and T3 with the strongbacks are designated as SAC9-SB and T3-SB, respectively. Nonlinear response history analyses (NRHA) of SAC9, T3, SAC9-SB, T3-SB models and the others with different properties of strongback systems were conducted using PISD3D program. The NRHA result shows that SAC9-SB and T3-SB have smaller standard deviations than those using other strongback properties. The analysis results confirm the effectiveness of the proposed method in proportioning the strongback for buildings.
標題鋼梁接箱型柱之內橫隔斷裂試驗與有限元素模型分析研究
作者吳忠哲、李昭賢、蔡青宜、林克強、莊勝智、蔡克銓
關鍵字鋼箱型柱、電熱熔渣焊、鋼材斷裂預測模型、鋼梁柱接頭、有限元素分析、圓周刻痕拉伸試驗、電熱熔渣焊儲倉口
摘要鋼箱型斷面柱構件具有雙強軸的特性,因此國內鋼建築結構中應用非常普遍。為傳遞梁端彎矩至柱構件,箱型柱內與梁翼同高處須配置與梁翼同厚的橫隔板。內橫隔板與柱板間焊接常使用電熱熔渣焊(Electro Slag Welding, ESW)工法,此種焊道施作便利且效率高,已大量使用於國內鋼結構製造廠。然而,ESW 施做時的高入熱量恐導致其焊道及其周圍母材結晶過大與抗衝擊性質較差,此現象亦常導致梁柱發生非預期的脆性破壞。為避免ESW 發生脆性破壞及量化ESW 破壞之機制,本研究採用既有的鋼材斷裂預測模型,利用有限元素模型對試體進行斷裂預測分析。本研究進行三組梁柱接頭試驗,藉由變化試驗之載重歷時與ESW 施工儲倉口截面形狀,探討試體破壞時機並驗證鋼材斷裂預測模型之可行性。實驗結果顯示證實累積塑性應變大小確實影響其破壞時機;ESW 儲倉口截面由矩形變為喇叭口形時,顯示若增加ESW 之熔透範圍可增加接頭試驗耐震性能。為應用斷裂預測模型,藉圓周刻痕拉伸(Circumferential Notched Tensile, CNT)試驗與有限元素模型分析,將所得之材料參數對ESW 元件試驗與梁柱接頭試驗進行斷裂預測分析。分析結果顯示,ESW 之幾何形狀及相對位置對於破壞時機影響甚大,因此顯示破壞預測分析與CNT 試驗之可行性,以及焊道超音波檢測(Ultrasonic Test, UT)之重要性。
TitleFracture Tests and Finite Element Analysis of Diaphragm Connection in Steel Beam-to-Box Column Joints
AuthorChung-Che Wu, Chao-Hsien Li, Ching-Yi Tsai, Ker-Chun Lin, Sheng-Jhih Jhuang, Keh-Chyuan Tsai
Keywordssteel box column, electro-slag welding, heat affected zone, fracture prediction model, steel beam-to-box column connection, finite element model analysis, circumferential notched tensile test, ultrasonic test
AbstractSteel box columns are widely used in steel building structures in Taiwan due to the strong axes in two directions. In order to transfer the beam end moment to column, diaphragm plates of the same thickness and elevations as beam flanges are usually welded inside box column. Electro-slag welding (ESW) process is typically used in attaching the diaphragms to column flanges. This ESW process has been widely used in steel beam-to-box column joints in Taiwan because of its’ convenience and efficiency. However, ESW may increase the hardness of the welds and heat affected zones (HAZs), while reduce the Charpy-V Notch (CVN) strength in HAZ. This situation could cause the diaphragm to column flange weld to suffer premature fracture before a large plastic rotation is developed in beam-to-box column joints. In order to quantify the critical eccentricity and the effectiveness of predicting the fractures, this study utilizes the fracture prediction model and finite element model (FEM) analysis to correlate the test results. In this study, three beam-to-box column connection subassembly tests have been conducted with a different loading protocol or the shape of ESW chamber. Test results show that the fracture instances can be predicted based on the cumulative plastic deformation in the HAZs. Tests confirm that the possible fracture of the diaphragm to column flange welds can be mitigated by enlarging the chamber of the ESW. When the fracture prediction model is applied, the material parameters were firstly established from the Circumferential Notched Tensile (CNT) tests and FEM analysis. Subsequently, these parameters were used to predict the fractures observed in the ESW component tests and beam-to-box column connection subassembly tests. The fracture locations and instances can be reasonably well predicted by a suitable FEM model analysis. Thus, the effectiveness of CNT and the fracture model are confirmed. Analytical results also show fracture instances and locations are sensitive to the relative locations of the ESW and the beam flange. Thus, the importance of ultrasonic test in assuring the quality of the ESW is evident.
標題考慮塗裝系統更新週期影響之鋼構橋梁生命週期成本評估方法建構
作者邱建國、陳正誠、陳敏祐
關鍵字鋼構橋梁、劣化速率、生命週期維護成本、防蝕塗裝系統
摘要鋼構橋梁於維護階段主要之費用分為定期維護成本及防蝕塗裝成本。對於定期維護成本而言,本研究主要使用貝氏更新決定構件/元件劣化速率,並且推估不同維護週期下之費用分布,以選擇成本最小之定期維護週期。防蝕塗裝成本除材料費用外須考慮施工費用,本研究主要參考歷史資料,以建立防蝕塗裝工程洐生之施工機具與相關費用推估模式。此外,為使設定之塗裝系統更換週期更貼近實務,本研究亦進行鋼構橋梁常用塗裝系統之耐用年限評估,除加速耐候試驗與現地曝曬試驗外,並參考文獻之塗膜消耗速率以建議不同性能要求下之對應耐用年限,以做為不同塗裝系統更新週期之設定依據。本研究以某直轄市之26 座鋼構橋梁為例,主要選取 8 項橋梁構件/元件,共包括:橋面板、支承、伸縮縫、面層、防落橋裝置、主結構、欄杆及護牆、排水設施等,利用上列元件/構件估算所得維護費用,再依係數進行修正以得出橋梁整體定期維護成本,並試算不同塗裝系統及更新週期下之費用,以了解其對生命週期維護成本之影響,可做為後續維護計畫之擬定參考。
TitleLife-cycle Cost Assessment Method Development for Steel Bridges Considering the Effect of the Renewal Periods of Coating Systems
AuthorC. K. Chiu, C. C. Chen, M. Y. Chen
Keywordssteel bridge, deterioration rate, life-cycle maintenance cost, anti-corrosion coating system
AbstractIn the maintenance stage of steel bridges, the costs can be divided into the regular maintenance cost and anti-corrosion coating cost. For the regular maintenance cost, this work adopts the Bayesian updating to determine the deterioration rate of each component or member. Additionally, based on the minimal regular maintenance cost, the corresponding maintenance period can be obtained. In order to quantify the renewal cost of the anti-corrosion coating system, this work conducts the accelerated-weathering test and site exposure test for the anti-corrosion coating materials. In addition to the testing results, the past investigations on the consuming rates of the specified coating materials for steel bridges are referred to determine the renewal periods of the anti-corrosion coating system. Finally, an assessment method of the life-cycle cost (LCC) of steel bridges is developed to investigate effect of the renewal period of the anti-corrosion coating system on the LCCs for 26 steel bridges located in a special municipality in Taiwan.
標題容量位移雙反應譜-基於損傷之鋼筋混凝土橋梁耐震設計與評估法
作者王柄雄、張國鎮、歐昱辰
關鍵字反應譜、非彈性位移比、損傷指標、平滑型遲滯模型、遠域地震、近斷層地震、耐震設計與評估、鋼筋混凝土橋梁
摘要本研究提出一套容量位移反應譜(Capacity-based inelastic displacement spectra),其係由一個非彈性位移比CR反應譜與一個相應之損傷指標DI反應譜所構成之雙反應譜(Dual spectra),可用於鋼筋混凝土橋梁之耐震性能設計與評估。反應譜之建置係藉由一個功能強大的平滑型遲滯模型,可考慮不同橋柱設計參數之影響,並分別就遠域及近斷層地震進行單自由度系統之非線性動力歷時分析而得。本研究證實在任何的位移加載歷程下,Park and Ang 所提出之損傷指標不但可用來準確地預測橋柱的強度衰減時機,更可作為評估橋柱真實可視破壞狀態的良好指標,進而得到較佳的橋梁耐震性能評估結果。採用遠域地震所計算之CR反應譜顯示,當結構週期約略大於0.8 秒時,非彈性位移比CR可近似滿足等位移原理;但就近斷層地震而言,在全部反應譜週期範圍內則皆不滿足此原理。此外,分析結果顯示近斷層地震會較遠域地震產生明顯較大的CR及DI值,且當相對強度比R = 5.0 時,大部分本研究所考量之設計方案皆無法承受所考慮之近斷層地震的侵襲。最後,根據所計算之反應譜分析結果,本研究分別就遠域及近斷層地震各提出一套非彈性位移比CR及相應之損傷指標DI之反應譜公式,並依據所建置之容量位移反應譜,提出一套基於損傷之鋼筋混凝土橋梁耐震性能設計與評估方法。
TitleCapacity-Based Inelastic Displacement Spectra for Seismic Design and Evaluation of Reinforced Concrete Bridges
AuthorPing-Hsiung Wang, Kuo-Chun Chang, Yu-Chen Ou
Keywordsspectrum, inelastic displacement ratio, damage index, smooth hysteretic model, far-field earthquake, near-fault earthquake, seismic design and evaluation, RC bridges
AbstractCapacity-based inelastic displacement spectra that comprised an inelastic displacement (CR) spectrum and a corresponding damage state (DI) spectrum was proposed in this study to aid seismic evaluation and design of reinforced concrete (RC) bridges. Nonlinear time history analyses of SDOF systems were conducted using a versatile smooth hysteretic model that accounted for the influences of various column design parameters when subjected to far-field and near-fault ground motions. It was proved that the Park and Ang’s damage index not only can be used to accurately predict the onset of strength deterioration, but also can be a good indicator for assessing the actual visible damage condition of column regardless of its loading history, providing a better insight into the seismic performance of bridges. The computed spectra show that the CR for far-field ground motions approximately conforms to the equal displacement rule for structural period (Tn) larger than around 0.8 seconds, but that for near-fault ground motions departs from the rule in the whole spectral regions. Moreover, the near-fault ground motions would lead to significantly greater CR and DI than far-field ground motions and most of the design scenarios investigated in this research cannot survive the near-fault ground motions when relative strength ratio R = 5.0. Based on the computed spectra, CR and DI formulae are presented as a function of Tn, R, and various design parameters for far-field and near-fault ground motions. Finally, application of the proposed spectra to the performance-based seismic design and evaluation of RC bridge was presented using DI as the performance objective.
標題以極值分析理論推估最佳設計風壓係數
作者羅元隆、Michael Kasperski
關鍵字設計風速、極值分布曲線、風壓係數、最佳設計非超越機率
摘要決定設計風載重大小取決於設計風速與設計風壓係數的評估。其中設計風速的評估由實場監測長年累積的數據經極值分析理論求得,因此首先必須對於標的物的氣象資料資訊進行了解。再者,設計風壓係數由標的物的幾何外型決定,可以經由正確的物理縮尺風洞試驗,在滿足各種無因次化參數條件下,獲得標的物每個局部位置的風壓係數值。設計風速與設計風壓係數的機率密度分布函數透過乘冪計算,必須滿足對於標的物破壞的目標超越機率。本研究以台灣本土的氣象資料進行設計風速的評估,輔以一簡單的高層建築物理縮尺實驗作為設計風壓係數的推算範例,推算出滿足於標的物分類及回歸期的最佳設計風壓係數值及其相對應之最佳設計非超越機率值、最佳設計風載重。
TitleEstimation of Design Pressure Coefficient Based on Extreme Value Analysis Theory
AuthorYuan-Lung Lo, Michael Kasperski
KeywordsDesign wind speed, Extreme value distribution, Pressure coefficient, Optimal design fractile
AbstractTo determine a proper design wind load relies on correct evaluations on design wind speed and design wind pressure coefficient. The evaluation on design wind speed requires the understanding of local meteorological information accumulated for a long-term period and the knowledge of extreme value analysis; wind pressure coefficient of the target structure can be obtained via properly arranged wind tunnel test fulfilling the satisfactory demand of all non-dimensional aerodynamic parameters. By satisfying the target exceedance probability of failure of a target building, convolution process of probability densities of design wind speed and pressure coefficients is carried out and then the optimal design pressure coefficient can be found through iterative calculation. This study intends to apply local meteorological information in Taiwan and a simple wind tunnel test to demonstrate the determination of the optimal design fractile and its corresponding design wind pressure coefficient and design wind load.

第三十三卷第三期 (期別131) (107年)

第三十三卷第三期 (期別131) (107年)

標題鋼筋混凝土圓形柱橫向鋼筋圍束效果之探討
作者李台光、陳正誠
關鍵字鋼筋混凝土圓形柱、橫向鋼筋、圍束效果
摘要本研究完成8支大尺寸鋼筋混凝土圓形柱試體之反復側向載重試驗,共規劃R、S33、S17 及D33 等4 個系列,以箍筋、繫筋總圍束力維持固定為原則,箍筋之圍束力以箍筋2 倍的斷面積與標稱降伏強度之乘積計算,而對於十字型及井字型配置之繫筋,分別以1 根及2 根繫筋斷面積與標稱降伏強度之乘積,計算繫筋之圍束力,探討井字型及十字型等2 種繫筋於圍束柱混凝土的可行性及有效性。研究結果顯示:(1)含十字型及井字型組合繫筋之鋼筋混凝土圓形柱,其耐震性能與側力方向具有某種關聯性,但並不顯著。故圓柱繫筋施工時應不需要特別旋轉或是調整十字型及井字型組合繫筋之方向或指定方向。(2)以本研究圍束力之定義,在相同總圍束力下,圓箍筋的圍束效果優於十字型及井字型配置之組合繫筋,另十字型繫筋比井字型繫筋圍束效果稍佳,組合繫筋之圓箍筋等效圍束力折減之計算,與繫筋配置形式及圍束力比有關,尚需後續進一步研究釐清。
TitleThe confinement effectiveness of transverse reinforcement in circular reinforced concrete columns
AuthorTai-Kuang Lee, Cheng-Cheng Chen
KeywordsCircular RC Columns, Transverse Reinforcement, Confinement Effectiveness
AbstractIn this study, a lateral cyclic load test was conducted on eight specimens of large-sized circular reinforced concrete (RC) columns to investigate the confinement effectiveness of circular ties and lap-spliced crossties. Totally, there are four series of specimens including R, S33, S17 and D33 constructed and tested. In single-cross crossties, the confining force of transverse reinforcement is calculated by adding the confinement effectiveness of one crosstie cross-sectional area. On the other hand, in double-cross crossties, the confining force of transverse reinforcement is calculated by adding the confinement effectiveness of two crosstie cross-sectional areas. The research results are presented as follows: (a) The seismic performance of circular RC columns with single-cross and double-cross lap-spliced crosstie correlates with the lateral loading direction. But its influence is not significant (b) The confinement effectiveness of circular tie is better than that of single-cross and double-cross lap-spliced crosstie. The reduction influence of lap-spliced crossties depends upon crosstie layout and the confinement force ratio. More details need further studies.
標題以應力波法非破壞檢測混凝土植筋epoxy握裹長度
作者鄧凱均、莊江隆、林宜清、江國睿
關鍵字植筋品質、非破壞檢測、應力波動、敲擊回音法
摘要本文開發以波動技術非破壞檢測植筋握裹長度與植筋深度。首先以有限元素法對植筋結構之應力波動訊號進行數值模擬分析,以瞭解植筋之波動行為,並經由植筋試體之敲擊回音試驗來驗證數值分析結果。研究結果顯示,在頻譜圖中可以發現明顯尖峰位於主導頻率上,該主導頻率主要由植筋外露長度與植筋握裹長度所控制,對特定之植筋外露長度時,植筋握裹長度越長所得頻率就越高。本文以數值分析建立三種不同植筋外露長度(10、15 與20公分),頻率與植筋握裹長度間之關係曲線。試驗檢測結果與數值模擬相當吻合。研究結果建議現場植筋握裹長度檢測程序如下:(1)以超音波測得植筋總長度,由測得之植筋總長度扣除外露長度即可求得植筋深度;(2)執行敲擊回音試驗測得主導頻率,代入所建立的迴歸方程式,即可以預估植筋握裹長度。試驗結果顯示預估之植筋握裹長度誤差大都在1 公分以內,證明本文所開發檢測法可以作為現地植筋施工品質之檢驗用。
TitleUse of Stress Wave methods for Nondestructive Inspection of Epoxy-Bonded Length of Post-installed Rebars in Concrete
AuthorKai-Chung Teng, Chiang-Lung Chuang, Yiching Lin, Guo-Ruei Jiang
Keywordsquality of planting bars, nondestructive evaluation, stress waves, impact-echo
AbstractThis article develops a stress wave-based technology to detect non-destructively the epoxy-bonded length and embedded depth of post-installed rebars in concrete. Firstly, the finite element method (FEM) was used to simulate the stress wave propagation signal of the post-installed rebars in concrete to understand the wave propagation behavior of anchorage rebar. The results of the numerical analysis were verified by the impact-echo test performed on the concrete specimens containing post-installed rebars. The results show that a high amplitude peak can be found at the dominant frequency in the spectrum. The dominant frequency is mainly controlled by the exposed length and the epoxy-bonded length of the post-installed rebar. For a specific exposed length of the planting rebar, the longer the epoxy-bonded length, the higher the dominant frequency. In this paper, numerical analysis of three different exposed lengths (10,15 and 20 cm) were considered to establish the relationship between the dominant frequency and the epoxy-bonded length. The experimental results are in good agreement with those obtained from the numerical simulation. The results obtained from this study suggested that the epoxy-bonded length of post-installed rebar can be evaluated as follows: (1) The total length of the post-installed rebar can be measured by ultrasound. The embedded depth of the post-installed rebar is obtained by deducting the exposed length from the measured total length; (2) Impact-echo test measured the dominant frequency. The epoxy-bonded length can be predicted by substituting the dominant frequency into the established regression equation. The test results show that the estimated error of embedding length of post-installed rebar is mostly within 1 cm, which proves that the test method developed in this paper can be used to evaluate the quality of planting bars.
標題台灣混凝土變形預測模式B4-TW 建置(ㄧ):基本潛變、乾燥潛變與總潛變
作者劉庭愷、陳振川
關鍵字混凝土、長期變形、潛變、收縮、資料庫
摘要台灣目前之混凝土工程設計規範缺乏混凝土潛變之預測公式,工程師設計大多依循美國ACI 規範,參考美國AASHTO 公路橋梁設計規範;歐洲CEB-FIP、RILEM;或日本JSCE、JCI 等作法。基於台灣混凝土材料、配比、施工與環境之地區特性,台灣著實需要發展良好之本土化混凝土潛變預測公式。本文指出運用現有之國內外混凝土潛變模式預測台灣混凝土資料之情形,結果顯示大多現有模式皆呈現低估的現象。本研究評估並選用Bažant 2015年提出之Model B4 潛變預測公式為基礎,針對上述之台灣混凝土特性進行本土化修正,分別是在瞬時應變項中考慮因粒料堅實度較為不足造成之混凝土彈性模數折減;在基本潛變項中考慮因高漿體量及粒料性質造成高變形之現象;在乾燥潛變項中考慮台灣常用之砂岩粒料造成之影響。結果顯示,進行本土化修正後之Model B4-TW 潛變預測公式與原始Model B4相比,預測台灣混凝土基本潛變資料時,迴歸分析中之決定係數 R2由 0.52提升至0.78;預測總潛變資料變形時R2由 0.76 提升至 0.81。除 R2外,各國學者提出之不同統計指標也顯示Model B4-TW 預測台灣潛變資料之表現較佳,建議發展成為適用台灣本土之混凝土潛變預測公式。
TitleEstablishment of B4-TW Prediction Model for Concrete Deformation in Taiwan ( I ) :Basic Creep, Drying Creep and Total Creep
AuthorTing-Kai Liu, Jenn-Chuan Chern
KeywordsConcrete, Long-term Deformation, Creep, Shrinkage, Database
AbstractAt present the concrete design code in Taiwan lacks any predictive model for concrete creep, which is why most engineers in Taiwan follow the models of the American Concrete Institute (ACI) or the American Association of State Highway and Transportation Officials (AASHTO) of the US; the European CEB-FIP and RILEM ; or the methods of the JSCE or JCI of Japan. Although the physical and chemical characteristics of concrete are essentially the same all across the world, each location uses its own constituent materials and mix design. In the present study, looking at the establishment of a concrete creep database for concrete in Taiwan, we have seen that the aggregate used in concrete of Taiwan is of lower quality. When formulating a mix design to attain higher strength, the resulting concrete will tend to have a high paste content, high cement content, low water cement ratio, and low aggregate/cement ratio. These local characteristics of concrete in Taiwan may lead to inaccuracies when they are applied to foreign predictive formulas, and in turn influence the structural behavior and safety of the concrete structures. Taiwan therefore has a manifest need for developing better localized predictive models for concrete creep. This study first presents the results from the predictive models for concrete creep (foreign and domestic formulas) applied to concrete in Taiwan. At present, it may be seen that the norms tend to undervalue. Then, it evaluates and actually uses the Model B4 predictive model for concrete creep suggested by Bažant in 2015 as a basis for the correction of characteristics in localized concrete in Taiwan in multiple situations: in instantaneous deformation items the reduction of the elasticity modulus in concrete due to low-quality aggregate was considered; in basic creep items the phenomenon of high levels of deformation due to high paste content and aggregate property were considered; in drying creep items the effect of sandstone aggregate, which is often used in Taiwan, was considered. Our results were as follows: after using the Model B4-TW model, which has been corrected for localized concrete in Taiwan, we may compare the two models (Model B4 and Model B4-TW); when predicting basic creep for Taiwan concrete, the coefficient of determination R2 rose from 0.52 to 0.78; when predicting the total strain, R2 rose from 0.76 to 0.81. In addition to R2, the statistical indicators given by scholars from around the world have shown that the predictive capabilities of the Model B4-TW model for concrete creep data in Taiwan are superior to other models; thus it can be further developed as a predictive model for concrete creep in Taiwan.
標題台灣混凝土變形預測模式B4-TW 建置(二):乾縮、自體收縮與總收縮
作者秦維邑、陳振川
關鍵字混凝土、長期變形、收縮、高爐石粉、飛灰、資料庫
摘要目前台灣之混凝土工程設計規範之混凝土收縮計算並未有明確公式,未能和混凝土材料之性質連結。致其計算常使用國外之美國 ACI、AASHTO,歐洲 CEB-FIP、RILEM 等預測公式。混凝土變形問題仍因牽涉世界各地區氣候環境、組成材料、配比及施工實務等,而有所差異性。台灣混凝土使用之粒料性質堅實度較為不足,配比設計時為追求強度達標,有使用高漿體量、高水泥量、低水灰比、低粒料量⁄水泥量比等特性,上述之本土化特性非使用國外預測公式可掌握,故台灣著實需要發展良好之本土化混凝土收縮預測公式。經評估現有國內外混凝土收縮預測規範,本文選用美國西北大學Bažant等人發展於2015 年提出之Model B4 收縮預測公式為基礎。針對上述之台灣混凝土特性進行本土化的修正,並考慮台灣常用之砂岩粒料造成之影響,找出適用於台灣之粒料修正參數。本文亦針對含有礦物摻料之混凝土進行摻料 影響之修正,選用FIB2000 作為自體收縮時間成長曲線,並修正Model B4 之礦物摻料參數表格,建立適合台灣使用之內含自體收縮項目的Model B4-TW 收縮預測公式。結果顯示,進行本土化修正後之Model B4-TW 收縮預測公式,在預測台灣普通混凝土或含有礦物摻料混凝土收縮時,均有極優表現,可發展為適用台灣本土之混凝土收縮預測公式。
TitleEstablishment of B4-TW Prediction Model for Concrete Deformation in Taiwan ( II ) : Drying Shrinkage, Autogenous Shrinkage and Total Shrinkage
AuthorWei-Yi Chin, Jenn-Chuan Chern
Keywordsconcrete, long-term deformation, shrinkage, blast-furnace slag cement, fly ash, dataset
AbstractAt present, there is no definite formula for concrete shrinkage calculation in the concrete engineering design code of Taiwan, which cannot link with the nature of local concrete material. Most engineers in Taiwan often use the formula of American Concrete Institution (ACI), the American Association of State Highway and Transportation Officials (AASHTO), and European CEB-FIP and RILEM codes. The problem of concrete deformation is still different because it involves the climate environment, mix design, proportion and construction practice in different areas. The aggregate quality of the concrete used in Taiwan is poor, and the mix is designed to achieve the strength with the use of high paste volume, high cement content, low water/cement ratio, low aggregate/cement ratio and other characteristics. The localization characteristics described above cannot be mastered by foreign prediction formula, so Taiwan really needs to develop a good local concrete shrinkage prediction formula. Based on the evaluation of the existing domestic and foreign concrete shrinkage prediction formulae, this paper chooses the model B4 shrinkage prediction formula developed in 2015 by Bažant of Northwestern University. With regard to the local characteristics of the concrete in Taiwan, and the effect of the commonly used sandstone aggregate in Taiwan, the modified parameters of the aggregate are found. In this paper, the influence of concrete containing mineral admixture is modified: the FIB2000 is selected as autogenous shrinkage time growth curve; and the mineral admixture parameter table of model B4 is modified. These local modifications led to the establishment of the Model B4-TW. The results show that the model B4-TW shrinkage prediction formula, which included autogenous shrinkage, after localization correction has excellent performance in predicting the shrinkage of normal concrete or concrete containing mineral admixture in Taiwan, and can be developed as a concrete shrinkage prediction formula for Taiwan.
標題鋼筋混凝土構架填充低台度磚牆之試驗研究
作者張順益、吳秉祈、巫垂晃
關鍵字鋼筋混凝土、低台度磚牆、反覆載重試驗、側推分析,剪力強度
摘要國內老舊校舍建築物在受到地震侵襲時,常因鋼筋混凝土構架內填充台度磚牆而發生短柱破壞。其中台度磚牆所提供的側向剪力強度,即是評估是否發生短柱破壞的重要因子,而台度磚牆的側向抗剪強度可能因其高寬比以及臨界破壞角的不同而有所差異。由於現行估算方法並未考慮台度磚牆高寬比的影響,因此並無法真實反應台度磚牆的側向剪力強度。本文特別針對低台度磚牆的側向抗剪強度進行三座試體的試驗研究,其中一座為空構架試體以及兩座填充不同高度之低台度磚牆構架試體,用來做為推估鋼筋混凝土構架內低台度磚牆側向剪力強度的重要依據。此三座試體除了進行反覆載重試驗之外,也利用側推模擬分析探討其耐震行為,將分析結果與試驗結果進行比較以推估低台度磚牆的側向剪力強度。從試驗結果可以得知低台度磚牆的高寬比為其側向剪力強度的重要因子之一,因此在推估低台度磚牆的側向剪力強度時,若能將高寬比這項因子適度的反應在計算的公式中,將可以更真實的預測台度磚牆的側向剪力強度。本研究已據此原則研擬出鋼筋混凝土構架填充低台度磚牆的剪力強度計算公式。
TitleExperimental Study of Reinforced Concrete Frame Filled with Low Masonry Window Spandrel
AuthorShuenn-Yih Chang, Ping-Chi Wu, Tsui-Huang Wu
KeywordsReinforced Concrete Building, Low Masonry Window Spandrel, Seismic Evaluation, Pushover Analysis
AbstractIn Taiwan area, structural damages caused by short column effect are very common in school buildings. The short column failure is closely related to the shear strength of the masonry window spandrel infilled within a reinforced concrete frame. The shear strength of a masonry window spandrel might be highly affected by its height-width ratio. However, this factor is not considered in the current evaluating formula and thus this formula seems unable to faithfully predict the shear strength. In fact, a formula for estimating the shear strength of a masonry window spandrel has been proposed. Because the height-width ratio of the masonry window spandrel was not considered in the formula its application is limited or might be inappropriate. To improve thisformula, three reinforced concrete frames were designed and fabricated for the cyclic loading tests for predicting the shear strength of a low masonry window spandrel within a reinforced concrete frame. One is a pure frame and the other two frames were infilled with different height of the masonry window spandrels. After conducting the cyclic loading tests of the three frames, the pushover analysis of each frame was also performed. Hence, after comparing the analytical result with the experimental results, the shear strength of the masonry window spandrel can be estimated. In this work, the height-weight ratio is chosen as an important factor for the newly proposed formula to estimate the shear strength of a low masonry window spandrel within a reinforced concrete frame. As a result, an improved formula for predicting the shear strength of the low masonry window spandrel within a reinforced concrete frame is proposed in this work.