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本研究開發一適用於ETABS分析軟體的結構物耐震分析輔助程式，主要目的為 (1) 提供國家地震工程研究中心《校舍結構耐震評估與補強技術手冊第三版》（簡 稱TEASPA V3）與《臺灣結構耐震評估與補強技術手冊》（簡稱TEASPA V4）之 輸入檔參數自動化輔助功能，如梁構件有效翼寬計算、梁柱構件有效長度計算、窗 台柱塑鉸位置調整等，讓在進行評估工作時，可以減少繁瑣之輸入與人為錯誤。(2) 以TEASPA V4之理論為依據，提出一修改後的柱塑鉸設定方式，提供自動化計算 與設置，除改善TEASPA V4柱構件使用軸力─彎矩 (axial force-moment, P-M) 互 制塑鉸可能收斂慢之情況，也讓僅有M3塑鉸功能之ETABS版本使用者，也可以 依TEASPA V4理論進行高層建物耐震評估。在簡化柱塑鉸上，假設地震造成之彎 矩與軸力為等比例增加，求得柱降伏時在P-M曲線上所對應之軸力，並依此軸力計算塑鉸容量。此外，亦提供可使用ATC-40容量震譜法或以耐震規範反算法求取耐 震能力之輔助功能，求得不同韌性容量下對應的耐震性能。以兩高層建物為例，分 析結果與TEASPA V3及TEASPA V4進行比對檢核，驗證內容包括基底剪力、耐 震性能、破壞行為的探討等，以驗證程式之正確性。本輔助程式與其使用說明可於 臺灣結構耐震評估側推分析法下載專區下載，網址為：
https://teaspa.ncree.org.tw/Home/DownloadFile/13

This research develops a seismic analysis auxiliary program for structures. The main objectives are (1) to provide automation assistance for input file of TEASPA (Taiwan earthquake assessment and strengthening of structures by pushover analysis) V3 and V4 developed by the National Center for Research on Earthquake Engineering, such as calculating the effective flange width of beams, the effective length of beams and columns, adjusting the plastic hinge position of windowsill columns, etc. This aims to reduce the tedious input work and minimize human errors for engineers. (2) Based on the theory of TEASPA V4, a modified model for column plastic hinges is proposed. It offers automated calculation of nonlinear hinge parameters, addressing to improve the slow convergence in using P-M interaction plastic hinges for columns. This modification also enables users of ETABS versions with only M3 plastic hinge function to conduct seismic assessments for high-rise buildings according to TEASPA V4. In modified P-M column hinges, the seismic-induced moment and axial force are assumed to increase proportionally. The corresponding axial force at the yield point of the P-M curve is determined, and the capacity of the column is calculated based on this force. Additionally, the program provides a function for determining seismic capacity using the ATC-40 capacity spectrum method or the method based on design code, obtaining seismic performance corresponding to different ductility. Two buildings are analyzed as examples, and the results are compared against TEASPA V3 and V4, including base shear strength, seismic performance, and discussions on failure modes to validate the accuracy of this program. The program can be downloaded at:                          https://teaspa.ncree.org.tw/Home/ DownloadFile/13

It has been shown that the current formula for predicting the shear strength of masonry window spandrel may not be reliable. Thus, a series of cyclically loading tests were conducted for the reinforced concrete (RC) frames with different heights of masonry window spandrels and then a new formula is proposed to predict the shear strength. Herein, a further study is focused on the effect of using these new and old formulas in pushover analysis of old RC buildings with masonry window spandrel. The results reveal: (1) The use of the old formula for high masonry window spandrel may underestimate its shear strength. Hence, it might be damaged first and there is no short column failure. As a result, the performance-target ground acceleration (Ap ) of the building under analysis will be overestimated; (2) There is no significant difference in Ap value for using either new or old formula if the building has low masonry window spandrel; (3) Some masonry window spandrels look like high masonry window spandrels and it is expected that a short column failure will occur for the RC building under analysis. However, it shows no short column failure. This is because these masonry window spandrels are low masonry window spandrels because they may have a large width or their brick bond has a large critical failure angle. Since the old shear strength formula underestimates the shear strength of the high masonry window spandrels, it is likely to cause these high masonry window spandrels fail first without short column failure in the pushover analysis. Consequently, the Ap value is overestimated. Thus, buildings with insufficient seismic resistance cannot be detected early. Based on this, it is strongly recommended that the authority should revise the old shear strength formula for masonry window spandrel to improve the reliability of seismic evaluation of RC buildings.

地震是地球上的主要災害之一，其影響涵蓋社會、經濟和環境等多個層面。然而目前對地震的預測能力有限，這促使許多研究者採取各種手段來應對可能發生的地震災害。像是地震早期警報 (earthquake early warning)、結構健康監測 (structural health monitoring) 和抗震建築等技術的開發，能夠在地震發生後迅速做出反應，減少損害。然而，這些方法的成功與否很大程度上依賴於豐富且具代表性的地震數據。由於大地震的發生頻率較低，因此可供分析的地震數據經常受到限制，特別是在地震發生較少或觀測技術尚未完善的地區。為了解決這一問題，本研究引入了變分自編碼器 (variational autoencoder, VAE) 這一種基於機械學習 (machine learning) 的方法，VAE 具有強大的學習和生成能力，能夠自動提取地震數據的特徵。通過應用地震資料在VAE上，能夠生成具有多樣性且保留原始特徵的人造地震，這為地震數據的模擬提供了新的途徑。而本研究中，本文首先使用單一事件下的數據921地震進行模擬，經過預處理後最終留下293筆資料，初步訓練結果表明VAE能夠生成具有多樣性且符合原始數據特徵的人造地震 (artifical earthquake)。後續進一步應用VAE 於台灣七個特定地區的地震資料，最終結果不斷地驗證地震數據應用於VAE的可行性，為結構工程與地震工程技術提供了更多可靠的數據，並提出未來的研究方向。

As one of the major disasters on earth, earthquakes and their impacts cover a wide range of social, economic, and environmental aspects. However, forecasting earthquakes is currently impracticable, so many researchers have adopted various measures to cope with possible earthquake effects, such as earthquake early warning (EEW), structural health monitoring (SHM), earthquake-resistant structures, etc. This development allows us to respond to events and reduce impacts quickly. Although those advances are successful, they heavily rely on the availability and variety of earthquake data, which is often limited for large earthquakes or areas that are not earthquake-prone. Therefore, not much earthquake data can be used for structural analysis due to the deficiency of observation. In order to address this issue, this study introduces the variational autoencoder (VAE), a machine learning (ML) based approach. VAE is a generative model capable of automatically extracting the seismic features and reproducing the earthquake data. Moreover, it can generate artificial earthquake waveforms with diversity by using the extracted features, which provides a new way to synthesize waveforms. In this study, the 921 earthquake was first adopted, and a total of 293 waveforms were used for training. The preliminary results show that VAE is great while generating artificial earthquake waveforms. Subsequently, VAE is applied to the earthquake data from seven regions in Taiwan, and the final results verify the feasibility. As a result, VAE can provide merits for the development of structural and earthquake engineering, and the paper ends by suggesting future research.

目前有助於隔震技術研發與隔震支承測試的大型壓剪試驗機，尤其是具有動態控制能力者，鮮少甚至不曾公開其動態特性與系統參數識別的研究報告。因此，對於國家地震工程研究中心雙軸向動態試驗系統提供研究與測試服務前，本研究規劃與執行一系列不同水平速度與位移振幅的三角波循環載重試驗，以及不同振動頻率與位移振幅的正弦波循環載重試驗，建立系統摩擦力（係數）與水平速度的關係式，並識別慣性力（等效質量），以更為清楚瞭解與掌握其動態特性。主要研究內容為三個階段：(1) 第一階段為在未加裝隔震支承下，進行一系列的三角波與正弦波循環載重試驗，其目的為求得試驗系統於垂直向空載下，對應不同水平速度之系統摩擦力（係數）與慣性力（等效質量）；(2) 第二階段採用經潤滑平面滑動摩擦隔震支承，於施加垂直軸向荷載為10 MN下，分別進行三角波與正弦波之循環載重試驗，並提出一迭代分析方法，識別系統摩擦力（係數）與水平速度之關係式；(3) 最後，將鉛心橡膠隔震支承與直接剪力測量系統串聯，使其排除試驗系統摩擦力和慣性力，進行一系列測試，並透過試驗結果的比較與探討，進一步證明雙軸向動態試驗系統數學模型的可靠性和直接剪力測量策略的可行性。

Large-scale testing machines with dynamic compression and shear testing capabilities play a crucial role in developing seismic isolation technology and testing full-scale seismic isolators. However, to date, relatively little research has been conducted on its dynamic performance verification and system parameter identification. Only a few studies have established the empirical model to predict the relationship between system friction and peak velocity of the Caltrans seismic response modification device (SRMD) test system in the University of California, San Diego (UCSD), based on the various characterization testing. To support academia and industry, the dynamic characteristics of the biaxial dynamic testing system (BATS) at the National Center for Research on Earthquake Engineering (NCREE) must be thoroughly investigated. When no specimens are installed, the system friction of BATS generated by the various sliding surfaces can be identified and mathematically characterized using the horizontal triangular reversed loading test results; then, the effective mass of BATS can be estimated using the horizontal sinusoidal reversal loading test results to solve the inertia force problem. Under vertical compression loading, it is assumed that the system friction of BATS and the shear force of the specimen are simply related to the applied total normal force (or vertical compression load) and horizontal excitation rate. An iteration methodology is proposed to identify and mathematically describe the dependency of the friction performance of BATS and the specimen on total normal forces (or vertical compression loads) and horizontal excitation rates by iterating the horizontal triangular and sinusoidal reversed loading test results. To simplify the tests, a lubricated flat sliding bearing is used as the specimen, subjected to horizontal triangular and sinusoidal reversed loading with a constant vertical compression load. The reliability of the proposed mathematical model for BATS and the feasibility of the proposed direct force measurement strategy are further demonstrated by comparing the calibrated force response with the directly measured response.