teacher – 第 9 頁 – 中華民國結構工程學會

標題	高強度竹節鋼筋之混凝土劈裂握裹性能與拉力伸展長度
作者	林克強、林垣彥、紀凱甯、莊勝智、王勇智
關鍵字	高強度鋼筋混凝土、伸展長度、鋼筋強度等級修正係數、劈裂指數、握裹應力
摘要	規範ACI 318-19 之竹鋼筋直線受拉伸展長度公式，增加鋼筋強度等級修正 Ψg鋼筋強度等級超過420 MPa 時，對於550 與690 MPa 者，須依規範ACI 318-14 的計算長度分別加長1.15 與1.3 倍。現行規範中鋼筋伸展長度設計公式是基於混凝土劈裂機制推導而得，混凝土的劈裂機制主要受混凝土與鋼筋接觸的性質影響，故本文的主要目的在探討鋼筋強度等級修正Ψg存在的合理性。本研究共進行20 組梁端的鋼筋握裹試驗試體，伸展鋼筋分別採用420、550 與690 MPa 三種強度等級之#10 鋼筋，同時也變化混凝土強度與劈裂指數兩參數。試驗結果顯示，20 組試體中的15 組試體發生如預期的混凝土劈裂破壞，試體之劈裂指數甚至達4.93。從試驗握裹應力的分析中也證實，若混凝土強度與劈裂指數分別採用70 MPa 與2.5 的上限限制時，規範ACI 318-14 計算所得之直線伸展長度的試驗平均握裹應力比介於1.72 至2.4 之間，可提供充分的安全餘裕，因此， ACI 318-19 之受拉伸展長度公式中，無需額外增加鋼筋強度等級修正增長因子 Ψ􀯚。若將混凝土強度與劈裂指數上限條件分別提升至100 MPa 與5.0，可獲得約 10%保守餘裕的準確結果，惟若應用於工程實務，應考量適當的安全係數。

Title	Bond Splitting Performance of Concrete and Development Length in Tension for High-Strength Deformed Bars
Author	Ker-Chun Lin, Yuan-Yan Lin, Kai-Ning Chi, Sheng-Jhih Jhuang, Yung-Chih Wang
Keywords	High-strength reinforced concrete, development length, modification factor of steel grade, split index, bond stress
Abstract	For ACI 318-19 Code, a modification factor of steel grade of Ψ􀯚 that is equal to 1.15 or 1.3 for 550 or 690 MPa grade of steel bar exceeding 420 MPa was added to increase straight development length in tension for deformed bar. It is known that the design equation of development length stipulated in the existing ACI 318 Code was obtained based on a mechanism of concrete splitting primarily dominated by contact characteristics between concrete and steel bar. This paper was intended to investigate the rationality of the Ψ􀯚 included in the design equation of development length. A total of 20 beam-end specimens was carried out to study bond behaviors of concrete splitting with a deformed bar in this research. A #10 bars for three various grades of 420, 550 and 690 MPa was used as developed steel bar per specimen. Concrete strength and split index were study parameters as well. Test results indicated that the anticipated concrete splitting occurred in 15 specimens of all 20 ones even took place in the specimens with the split index of 4.93. Based on analysis overcomes of the test bond stress in this research, it was confirmed that under upper limitations of 70 MPa for the concrete strength and 2.5 for the split index, the average bond stresses of the three various grade bars for ACI 318-14 Code ranged from 1.72 to 2.4. The modification factor of steel grade of Ψ􀯚 seemed to not be needed in the provisions of straight development length of ACI 318-19 Code. It was certificated as well that raising the limit limitations of 100 MPa for the concrete strength and 5.0 for the split index, good results with around 10% conservative margin could be obtained according to the provisions of straight development length of ACI 318-14 Code. However, a safety factor should be considered for applications of engineering practice.

建立臺灣普通及摻料混凝土強度及彈性模數時間成長函數研究

標題	建立臺灣普通及摻料混凝土強度及彈性模數時間成長函數研究
作者	王映捷、廖文正
關鍵字	飛灰、爐石、強度、彈性模數、時間函數
摘要	混凝土是由粒料、水泥、礦物摻料、水等材料，依配比設計產生之複合材料；又混凝土結構物之生命週期需考量安全性及長期服務性，其硬固後體積會受外力作用而變化，如因環境乾燥所產生的收縮、受持續載重產生潛變等現象，皆會影響結構物之長期行為。混凝土彈性模數受組成材料等因素影響甚鉅，彈性模數的增長也會直接影響收縮潛變的評估，但因為各地所使用之組成材料不甚相同，因此有臺灣本土化之預測模型是非常重要的。目前臺灣已經有本土化之收縮潛變模型，但缺乏混凝土強度及彈性模數之時間函數。有鑑於彈性模數、強度在工程應用上的重要性，以及近年來添加飛灰、水淬高爐爐碴粉等摻料混凝土被廣泛使用，因此本研究將從臺灣混凝土收縮潛變資料庫出發，以7 種不同水灰比之普通混凝土及固定水膠比為0.42 之6 種飛灰、爐石取代量之摻料混凝土，分別配合3、 7、14、28、56、91、180 天的齡期，進行抗壓及彈性模數試驗，提出普通混凝土之強度及彈性模數預測式及時間成長函數，再進一步修正摻料混凝土之相關模型，除了可供修正臺灣本土化收縮潛變模型外，也能提供工程界預測使用。

Title	Establishment of Time Dependent Functions for Ordinary and Pozzolanic Concrete Compressive Strength and Modulus of Elasticity in Taiwan
Author	Ying-Chieh Wang, Wen-Cheng Liao
Keywords	fly ash, slag, strength, elastic modulus, time function
Abstract	Concrete is a widely used construction material composed of aggregate, cement, water, mineral admixture in a specific proportion. Not only safety, long-term serviceability is also the main consideration for buildings and infrastructures made of concrete. The volume of concrete changes over time, such as shrinkage and creep, and all the above influence the long-term serviceability. The elastic modulus of concrete, mainly determined by composition of concrete, directly affects shrinkage and creep behaviors of concrete. However, because materials vary from different resources, a localized prediction model is essential to account for characteristics of concrete in Taiwan and this specific prediction model shall involve localized time function of strength and elastic modulus as well. In view of the importance of elastic modulus and strength in practical applications, and in recent years, the addition of fly ash and water-quenched blast furnace slag in concrete has been widely used, so this research also investigates the shrinkage and creep test data from the database. A comprehensive experimental program, including compression and elastic modulus tests for seven different water-to-cement ratios of ordinary concrete and six different fly ash and slag replacement ratios of water-to-binder ratio of 0.42 for 3, 7, 14, 28, 56, 91 and 180 days, were conducted. The prediction models of time function for strength and elastic modulus for ordinary and fly ash/slag concrete in Taiwan are proposed for further modification of shrinkage and creep model and practical applications.

淺談二階分析於鋼結構設計之應用

標題	淺談二階分析於鋼結構設計之應用
作者	彭瑞麟、呂良正、陳紹禮、劉耀鵬、陳惠發
關鍵字	臨界載重、直接分析法、假想側向力、初始缺陷、二階分析
摘要	近年來歐美等先進國家的鋼結構設計規範中，多建置有二階分析（Second-order analysis）或直接分析(Direct analysis method)的相關規定。事實上二階分析即幾何非線性分析，歐盟及大英國協國際組織內家的鋼結構設計規範採用此名詞；美國工程界認為二階分析與二階彎矩兩個名詞易混淆，故在其鋼結設計規範中採用直接分析法取代二階分析。傳統鋼結構設計以各類構件強度為依據進行，是一種間接計的概念。二階分析則是依據整體結構系統強度和穩定進行設計，是一種直接且更為合理的設計方式，因而受到歐美等先進國家鋼結構設計規範採用。二階分析尤其適合用於水平梁及非垂直柱之組合、且造型不規則又兼具美學外觀、有效長度難以確定的鋼構造物的設計。本文針對歐美等先進國家鋼結構設計規範採用的二階分析情形做初步介紹；為方便工程師掌握內容，文中特別將各國鋼結構設計規範中與二階分析及直接分析法相關的章節做重點節錄。期望經由本文的介紹，能讓國內工程師瞭解先進國家鋼結構設計的發展，未來的設計能與國際同步。

Title	Brief Introduction to Applications of Second-order Analysis in Design of Steel Structures
Author	Jui-Lin Peng, Liang-Jenq Leu, Siu-Lai Chan, Yao-peng Liu, Wai-Fah Chen
Keywords	Critical load, Direct analysis method, Notional lateral force, Initial imperfection, Second-order analysis
Abstract	In recent years, the steel structural design codes of advanced countries such as Europe and the United States have stipulated the related regulations of “second-order analysis” or “direct analysis method.” In fact, the second-order analysis, widely adopted in the steel structural design codes of the European Union and the Commonwealth of Nations, is the geometric nonlinear analysis. The American engineering community believes that the terms of “the second-order analysis” and “the second-order bending moment” are easily confused, so the “direct analysis method” is used to replace the “second-order analysis” in the steel structural design code. Traditional steel structural design is mostly carried out on the basis of component strength, which is an indirect design concept. The second-order analysis is designed based on the strength and the stability of the overall structural system. It is a direct and more reasonable design method, which is the reason for the adoption of steel structural design codes in advanced countries such as Europe and the United States. The second-order analysis is especially suitable for the design of steel structures that combine nonhorizontal beams and non-vertical columns, have irregular shapes and aesthetic appearances, and is difficult to determine the effective length. This paper makes a preliminary introduction to the second-order analysis of steel structural design codes in advanced countries such as Europe and the United States. In order to make it easier for engineers to grasp the content, the paper especially makes key excerptions from chapters related to the second-order analysis and the direct analysis method in the steel structural design codes of various countries. It is hoped that through the introduction of this paper, domestic engineers can understand the development of steel structural design in advanced countries, and their designs can be synchronized with international designs in the future.

預鑄工法大小梁部分剛性接合之設計

標題	預鑄工法大小梁部分剛性接合之設計
作者	吳子良、黃世建
關鍵字	預鑄工法、部分剛性接合、剪力傳遞
摘要	土木水利學會與台灣混凝土學會於105 年著手修訂「混凝土結構設計規範」[1]之第九章「預鑄混凝土構材」設計規定條文，業經營建署於106年8 月核定公布實施[2]。修訂之規範條文僅作原則性描述，設計人員不易理解；本文，主要就規範之部分剛性接合設計作補充說明，包括規範修訂主要內容說明、預鑄小梁之結構模型建立、部分剛性接合之定義與設計、及鋼筋細則等。特別針對部分剛性接合之預鑄小梁傳遞剪力提出可能破壞之路徑及計算公式，讓設計者參考；最後，並提供計算案例作為說明，讓有志從事預鑄設計工作者得到充份的瞭解。

Title	Design of partial rigid joint of precast girder and beam
Author	Tzu-Liang Wu, Shyh-Jiann Hwang
Keywords	precast, partial rigid joint, shear transfer
Abstract	In 2016, the Chinese Institute of Civil and Hydraulic Engineering and the Taiwan Concrete Institute began to revise the design provisions of Chapter 9 of the ” Design Code of Concrete Structures [2] “, “Precast concrete Structures”, which were approved and published by the Construction and Planning Agency Ministry of the Interior in August 2017 [3]. The revised provision is only a principle description, which is not easy for designers to understand; this article mainly provides supplementary explanations on partial rigid joint design of the code, including the description of the main content of the revised provisions, the establishment of the structural model of the precast beams, and the definition of partial rigid joint and design, and reinforcement details, etc. In particular, the path and calculation formula for possible failure of the shear force transmitted by the partial rigid join between girder and beam are proposed for the designer’s reference. Finally, a design case is provided as an illustration, so that those interested in precast design can fully understand.

挫屈束制斜撐鋼構架近斷層地震反應：一樓柱側位移及柱軸力加載歷時發展

標題	挫屈束制斜撐鋼構架近斷層地震反應：一樓柱側位移及柱軸力加載歷時發展
作者	劉郁芳、周中哲、彭冠儒、陳冠儒
關鍵字	靜態往覆加載，加載歷時，近斷層地震，非線性動力歷時分析，挫屈束制斜撐
摘要	國內多以美國AISC 規範中抗彎矩構架梁柱接頭加載歷時作為鋼構試驗參考依據，並未制訂挫屈束制斜撐構架(BRBF)之載重歷時，但因不同構架加載歷時對於結構的非線性行為無法真實反應，且一樓柱在反應建築物行為上最具代表性，因此提出建立BRBF 的一樓柱軸力變化及側向位移往覆加載歷時計劃。台灣居住在鄰近活動斷層10 公里內之人口超過860 萬人，受到近斷層地震機率相當高，若參考美國規範標準載重歷時，將無法反應國內近斷層效應帶來的破壞，因此提出一套涵蓋台灣地理特性考量之鋼構造加載歷時乃十分必要。本研究已完成不同週期BRBF 的非線性靜力側推及非線性動力歷時分析，瞭解BRBF 在地震作用下力學行為，並提出BRBF 之加載歷時建議，期望能作為未來國內鋼結構研究之參考依據。

Title	Lateral displacement and axial force protocols of the first-story steel column in buckling-restrained braced frames under near-fault earthquake motions
Author	Yu-Fang Liu, Chung-Che Chou, Guan-Ru Peng, Kuan-Ju Chen
Keywords	static cyclic loading, loading protocol, near-fault earthquakes, nonlinear dynamic analysis, buckling-restrained brace
Abstract	Most of the domestic researchers considered the loading protocol for beam to column moment connections in moment resisting frame (MRF), specified by AISC, as the reference for static cyclic test. The loading protocols for buckling restrained braced frame (BRBF) had not been developed yet. The nonlinear behavior of a structure cannot be truly reflected using the loading protocols of different type of structure. Since the first story columns are generally used to represent the seismic behavior of a building, loading protocols for the first story columns in BRBF with varied axial force and lateral drift should be developed. Moreover, the loading protocols suggested by American specifications might omit the effect of near-fault earthquakes which is common in Taiwan. Therefore, the near-fault effect on buildings is necessary to be considered for better developing the loading protocols for BRBF in Taiwan. This research has completed the nonlinear static and nonlinear dynamic analysis of BRBF which is designed with various periods for a better understanding of seismic performances of BRBF and developing loading protocols for the first story columns in BRBF with varied axial force and lateral drift. The developed loading protocols for BRBF is expected to be a beneficial reference to steel structure study in the future.

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Vol.37/No.1 (143) (2022)

2022 年 4 月 29 日2022 年 4 月 26 日作者: teacher

Vol.37/No.1(143)(2022)

Bond Splitting Performance of Concrete and Development Length in Tension for High-Strength Deformed Bars

Title	Bond Splitting Performance of Concrete and Development Length in Tension for High-Strength Deformed Bars
Author	Ker-Chun Lin, Yuan-Yan Lin, Kai-Ning Chi, Sheng-Jhih Jhuang, Yung-Chih Wang
Keywords	High-strength reinforced concrete, development length, modification factor of steel grade, split index, bond stress
Abstract	For ACI 318-19 Code, a modification factor of steel grade of Ψ􀯚 that is equal to 1.15 or 1.3 for 550 or 690 MPa grade of steel bar exceeding 420 MPa was added to increase straight development length in tension for deformed bar. It is known that the design equation of development length stipulated in the existing ACI 318 Code was obtained based on a mechanism of concrete splitting primarily dominated by contact characteristics between concrete and steel bar. This paper was intended to investigate the rationality of the Ψ􀯚 included in the design equation of development length. A total of 20 beam-end specimens was carried out to study bond behaviors of concrete splitting with a deformed bar in this research. A #10 bars for three various grades of 420, 550 and 690 MPa was used as developed steel bar per specimen. Concrete strength and split index were study parameters as well. Test results indicated that the anticipated concrete splitting occurred in 15 specimens of all 20 ones even took place in the specimens with the split index of 4.93. Based on analysis overcomes of the test bond stress in this research, it was confirmed that under upper limitations of 70 MPa for the concrete strength and 2.5 for the split index, the average bond stresses of the three various grade bars for ACI 318-14 Code ranged from 1.72 to 2.4. The modification factor of steel grade of Ψ􀯚 seemed to not be needed in the provisions of straight development length of ACI 318-19 Code. It was certificated as well that raising the limit limitations of 100 MPa for the concrete strength and 5.0 for the split index, good results with around 10% conservative margin could be obtained according to the provisions of straight development length of ACI 318-14 Code. However, a safety factor should be considered for applications of engineering practice.

Establishment of Time Dependent Functions for Ordinary and Pozzolanic Concrete Compressive Strength and Modulus of Elasticity in Taiwan

Title	Establishment of Time Dependent Functions for Ordinary and Pozzolanic Concrete Compressive Strength and Modulus of Elasticity in Taiwan
Author	Ying-Chieh Wang, Wen-Cheng Liao
Keywords	fly ash, slag, strength, elastic modulus, time function
Abstract	Concrete is a widely used construction material composed of aggregate, cement, water, mineral admixture in a specific proportion. Not only safety, longterm serviceability is also the main consideration for buildings and infrastructures made of concrete. The volume of concrete changes over time, such as shrinkage and creep, and all the above influence the long-term serviceability. The elastic modulus of concrete, mainly determined by composition of concrete, directly affects shrinkage and creep behaviors of concrete. However, because materials vary from different resources, a localized prediction model is essential to account for characteristics of concrete in Taiwan and this specific prediction model shall involve localized time function of strength and elastic modulus as well. In view of the importance of elastic modulus and strength in practical applications, and in recent years, the addition of fly ash and water-quenched blast furnace slag in concrete has been widely used, so this research also investigates the shrinkage and creep test data from the database. A comprehensive experimental program, including compression and elastic modulus tests for seven different water-to-cement ratios of ordinary concrete and six different fly ash and slag replacement ratios of water-to-binder ratio of 0.42 for 3, 7, 14, 28, 56, 91 and 180 days, were conducted. The prediction models of time function for strength and elastic modulus for ordinary and fly ash/slag concrete in Taiwan are proposed for further modification of shrinkage and creep model and practical applications.

Brief Introduction to Applications of Secondorder Analysis in Design of Steel Structures

Title	Brief Introduction to Applications of Second-order Analysis in Design of Steel Structures
Author	Jui-Lin Peng, Liang-Jenq Leu, Siu-Lai Chan, Yao-peng Liu, Wai-Fah Chen
Keywords	Critical load, Direct analysis method, Notional lateral force, Initial imperfection, Second-order analysis
Abstract	In recent years, the steel structural design codes of advanced countries such as Europe and the United States have stipulated the related regulations of“second-order analysis” or “direct analysis method.” In fact, the second-order analysis, widely adopted in the steel structural design codes of the European Union and the Commonwealth of Nations, is the geometric nonlinear analysis. The American engineering community believes that the terms of “the secon-dorder analysis” and “the second-order bending moment” are easily confused, so the “direct analysis method” is used to replace the “second-order analysis” in the steel structural design code. Traditional steel structural design is mostly carried out on the basis of component strength, which is an indirect design concept. The second-order analysis is designed based on the strength and the stability of the overall structural system. It is a direct and more reasonable design method, which is the reason for the adoption of steel structural design codes in advanced countries such as Europe and the United States. The second-order analysis is especially suitable for the design of steel structures that combine nonhorizontal beams and non-vertical columns, have irregular shapes and aesthetic appearances, and is difficult to determine the effective length. This paper makes a preliminary introduction to the second-order analysis of steel structural design codes in advanced countries such as Europe and the United States. In order to make it easier for engineers to grasp the content, the paper especially makes key excerptions from chapters related to the second-order analysis and the direct analysis method in the steel structural design codes of various countries. It is hoped that through the introduction of this paper, domestic engineers can understand the development of steel structural design in advanced countries, and their designs can be synchronized with international designs in the future.

Design of partial rigid joint of precast girder and beam

Title	Design of partial rigid joint of precast girder and beam
Author	Tzu-Liang Wu, Shyh-Jiann Hwang
Keywords	precast, partial rigid joint, shear transfer
Abstract	In 2016, the Chinese Institute of Civil and Hydraulic Engineering and the Taiwan Concrete Institute began to revise the design provisions of Chapter 9 of the ” Design Code of Concrete Structures [2] “, “Precast concrete Structures”, which were approved and published by the Construction and Planning Agency Ministry of the Interior in August 2017 [3]. The revised provision is only a principle description, which is not easy for designers to understand; this article mainly provides supplementary explanations on partial rigid joint design of the code, including the description of the main content of the revised provisions, the establishment of the structural model of the precast beams, and the definition of partial rigid joint and design, and reinforcement details, etc. In particular, the path and calculation formula for possible failure of the shear force transmitted by the partial rigid join between girder and beam are proposed for the designer’s reference. Finally, a design case is provided as an illustration, so that those interested in precast design can fully understand.

"Lateral displacement and axial force protocols of the first-story steel column in buckling-restrained braced frames under near-fault earthquake motions"

Title	Lateral displacement and axial force protocols of the first-story steel column in buckling-restrained braced frames under near-fault earthquake motions
Author	Yu-Fang Liu, Chung-Che Chou, Guan-Ru Peng, Kuan-Ju Chen
Keywords	static cyclic loading, loading protocol, near-fault earthquakes, nonlinear dynamic analysis, buckling-restrained brace
Abstract	Most of the domestic researchers considered the loading protocol for beam to column moment connections in moment resisting frame (MRF), specified by AISC, as the reference for static cyclic test. The loading protocols for buckling restrained braced frame (BRBF) had not been developed yet. The nonlinear behavior of a structure cannot be truly reflected using the loading protocols of different type of structure. Since the first story columns are generally used to represent the seismic behavior of a building, loading protocols for the first story columns in BRBF with varied axial force and lateral drift should be developed. Moreover, the loading protocols suggested by American specifications might omit the effect of near-fault earthquakes which is common in Taiwan. Therefore, the near-fault effect on buildings is necessary to be considered for better developing the loading protocols for BRBF in Taiwan. This research has completed the nonlinear static and nonlinear dynamic analysis of BRBF which is designed with various periods for a better understanding of seismic performances of BRBF and developing loading protocols for the first story columns in BRBF with varied axial force and lateral drift. The developed loading protocols for BRBF is expected to be a beneficial reference to steel structure study in the future.

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第16屆結構工程研討會暨第6屆地震工程研討會

2022 年 3 月 23 日作者: teacher

各位專家學者您好,

第16屆結構工程研討會暨第6屆地震工程研討會由台灣科技大學營建工程系、結構工程學會、地震工程學會主辦，

會議日期：2022年8月24日(星期三)~26日(星期五)，

會議地點：淡水將捷鬱金香酒店(新北市淡水區中正路一段2-1號)，

會議形式：實體(on-site)方式進行。

報名網頁：https://www.ncree.org/conference/index.aspx?n=N20220824A2

敬邀大家踴躍報名參加、投稿或協助宣傳。

中華民國結構工程學會敬啟-2/23/2022

國震中心111年4月22日(四)的工程技術講座資訊

2022 年 3 月 22 日作者: teacher

2022工程技術講座(1)

主辦單位：財團法人國家實驗研究院國家地震工程研究中心、中華民國結構工程學會。

協辦單位：築遠工程顧問有限公司、永峻工程顧問股份有限公司、中華民國鋼結構協會。

時間：民國111年4月21日 (星期四)。

地點：國家地震工程研究中心一樓R101會議室。

費用：400元整，民國111年4月15日(星期五)前截止報名。

名額：講座人數預計75人，依報名順序，額滿為止。

工程技術講座(1)當天下午2點安排上海商銀總部(中山北路與民權東路交叉口)工程參觀，

請於報名基本資料中的工程參觀欄位勾選是否參加工程參觀，參觀人數預計15人，

依報名繳費完成順序，額滿為止

報名方式：即日起開始報名，請上網址：https://conf.ncree.org.tw/indexCht.aspx?n=A11103310

備註：本研討會已向行政院公共工程委員會申請技師積點及公務人員終身學習護照相關證書。

聯絡人：莊勝智/sjjhuang@ncree.narl.org.tw

紀凱甯/ knchi@narlabs.org.tw

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「結構工程」季刊第142期(第36卷第4期)

2021 年 12 月 29 日2021 年 12 月 28 日作者: teacher

「結構工程」季刊第142期(第36卷第4期)

電子檔已經上線。歡迎會員登入後下載全文。

中文網址: 第36卷第4期 (2021)

英文網址: Vol.36 / No.4 (2021)

若有任何意見歡迎 email 至 csse@csse.org.tw。

Vol.36/No.4 (142) (2021)

2021 年 12 月 29 日2021 年 12 月 27 日作者: teacher

Vol.36/No.4 (142) (2021)

Detailed evaluation and its checking for seismic performance of steel building structures

Title	Detailed evaluation and its checking for seismic performance of steel building structures
Author	Lap-Loi Chung, Dan Chiao, Min-Lang Lin, Jing-Fang Liang, Tsung-Chih Chiou, Kai-Wen Deng
Keywords	steel structure, nonlinear hinge, pushover analysis, detailed evaluation method of seismic capacity
Abstract	With the evolution of the times and the development of the code, the existing steel structures may also be insufficient in earthquake resistance, which need to be evaluated and reinforced. The detailed evaluation method of steel structure is a continuation of the principle of the detailed evaluation method of seismic capacity of reinforced concrete buildings. It is based on the capacity spectrum method and nonlinear static pushover analysis by using ETABS program. In this paper, the rationality and applicability of the nonlinear hinge are checked by referring to ASCE 41-13. After the capacity curve (the relationship between the structural base shear and the roof displacement) is obtained from the pushover analysis, this paper further proposes the checking method, including the structural stiffness (the slope of the capacity curve) and the maximum base shear, so as to confirm the rationality of the pushover analysis results, and avoid the poor communication between the engineer and the analysis program, which leads to systematic errors. If the engineer fails to detect the error of the analysis result immediately, he may misjudge the evaluation result seriously. Finally, a case is used to evaluate the seismic capability in detail, and then the evaluation results are verified to be reasonable.

Simplified Seismic Detailed Evaluation Method on Mid-to High-Rise Buildings

Title	Simplified Seismic Detailed Evaluation Method on Mid-to High-Rise Buildings
Author	Kai-Wen Teng, Chu-Yuan Chang, Yu-Chih Lai, Lap-Loi Chung, Tao Lai, Gin-Show Liu
Keywords	maximum base shear, seismic evaluation, simplified seismic evaluation method
Abstract	To find out the buildings with less seismic capacity is an important issue. However, conducting detailed evaluation for all buildings will cost a lot and uneconomical. This article focuses on Simplified Seismic Detailed Evaluation for mid-rise to high-rise buildings. The method needs not to use structural analysis software to obtain the results, but only consider strength of member, failure mode, etc. The article uses Ultimate Moment Balanced Method to evaluate the maximum base shear of building and assesses the seismic ability of the building. The result of Simplified Seismic Detailed Evaluation can be reference for engineers to check with Seismic Detailed Evaluation. The article adopts both Simplified Seismic Detailed Evaluation and Seismic Detailed Evaluation for a mid-rise to high-rise building to compare the differences of two methods. The Seismic Detailed Evaluation in the article is the method provided by NCREE. The results show that the base shear and seismic ability evaluated by both two methods only with minor difference. The method can be proposed to conduct seismic evaluation on mid-rise to high-rise buildings.

Seismic Analysis of NCREE Office Building Extension

Title	Seismic Analysis of NCREE Office Building Extension
Author	Guan-Hong Lin, Ming‐Chieh Chuang, Keh-Chyuan Tsai, Jui-Liang Lin
Keywords	Composite structure, RC structure, Steel structure, RC shear wall, FRP strengthening, BRB, SPD, FVD, PISA3D, Nonlinear response history analysis
Abstract	This study conducts the seismic analysis of NCREE office building extension. The extended NCREE building becomes a composite structure including the original six-story RC structure with RC shear walls and FRP strengthened beams, vertically added seven-story steel structure with BRBs, SPDs and FVDs. In addition, a service core was extended from the first floor to the roof at the north side of the building. PISA3D program was used for conducting the modal and nonlinear response history analyses (NRHAs). Bilinear, degrading, hardening material models were adopted for RC beam and column, RC shear wall, steel members, BRB and SPD. Maxwell model was applied on FVDs. In order to gain insight into the force transfers between the RC structure and steel service core interfaces, dual rigid diaphragms with two individual mass centers and several 6DOF joint elements were incorporated into the lower six floors of the structural model. Single rigid diaphragm and mass center were considered in all other floors. Modal analysis results show that the first three natural periods are 1.24s (longitudinal translation), 1.19s (transverse translation and rotation) and 1.05s (rotation), respectively. A total of 21 sets of ground accelerations and scaling factors were chosen in fitting the Taipei Zone 2 DBE design spectrum. The scale factors range from 2.22 to 6.35. 0921TAP042 earthquake scaled spectrum is closest to the design spectrum among all selected earthquake records. SLE and MCE earthquake hazard levels are 0.29 and 1.3 times of DBE, respectively. Under three different earthquake hazard (SLE, DBE, MCE) levels, maximum story drifts (SD) are distributed evenly in the LG direction but unevenly in the TR direction and coupled with rotation. Obvious story rotations occurred from the 2nd to the 7th floor. The averaged SDs occur at the LG 7th floor and TR 5th floor, which are 0.35, 1.22, 1.61% radians and 0.34, 1.12, and 1.52% radians respectively. In the DBEs, the SDs are less than 1.5% radians, and within the ASCE/SEI 7-10 limitation of the risk3 category having an importance between hospital and general buildings. In the MCEs, SDs are less than 2% radians within the FEMA356 performance limitation for life safety. Through the results of NRHAs, the satisfactory seismic performance of the extended NCREE building can be demonstrated.

Study on the Earthquake Response of Shulin Art & Administrative Building in New Taipei City

Title	Study on the Earthquake Response of Shulin Art & Administrative Building in New Taipei City
Author	Cheng, Li-Hui
Keywords	system identification, earthquake response, building health monitoring, vibration period, building period
Abstract	For promoting the building safety AI system, Taiwan Architecture & Building Center installed an earthquake monitoring system including four triaxial seismometers and a host computer in Shulin Art & Administrative Building in New Taipei City for health monitoring in October, 2020. Earthquake response data of the building will be collected by the system in the following consecutive three years. The research is based on the data recorded from the earthquakes on Dec.10, 2020 and Jan. 09, 2021 in North Taiwan. By system identification methods, the periods of the building are 0.3 second in X direction and 0.35 second in Y direction while the results of damping ratio are about 3%~5%. Since the building was just finished in July 2019, the identification results from the above earthquake records can be regarded as the initial properties of the structural stiffness which could be the reference for the building health monitoring in the future. In addition, the identified periods of the studied building are only 1/3 of both the empirical equation of Taiwan’s earthquake designing code and dynamic analysis of ETABS base on a mere RC frame model assumption. Thus, the research infers that, without taking the inner and outer walls into analysis consideration, the estimation of building periods will be much different from the actual values. Furthermore, in the studied building, the designing earthquake forces based on the empirical period equation might be less 10% than the forces based on the periods given from the identification results. In the result, the research proposes that the relationship between the periods and building categories shall be studied more thoroughly.

Optimal Sensors Placement for Micro-Vibration Monitoring of Mid-High Rise Building

Title	Optimal Sensors Placement for Micro-Vibration Monitoring of Mid-High Rise Building
Author	Yen-Yu Yang, Leng-Jenq Leu
Keywords	Optimal Sensors Placement, Structural Health Monitoring, Stochastic Subspace Identification, Cubic Spline Interpolation
Abstract	Taiwan is located in the seismic zone with high frequency earthquake occurrences. In order to increase structure safety, it needs to monitor the structural health before and after disaster occurs. This study proposes a method to obtain the optimal sensors placement(OSP), which could reduce the number of sensors for building monitoring. In additions, the method could find out the higher modal frequencies for structures. First, collect the real time-histories and use Cubic spline interpolation method to obtain simulated time-histories for each floor. Second, use Stochastic Subspace Identification to generate stabilization diagrams. Third, K-means clustering method is used to obtain modal frequencies. Finally, use Genetic Algorithm method to find OSP. There are four in-situ experiments for the method verifying, one is in National Taiwan University Cancer Center, one in Tamsui(a new building) and others are 5 years buildings in Banqiao.

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