新一代房屋結構耐震性能評估法之簡易評估法研究

Simplified Analysis Procedures for Next-Generation Performance-Based Earthquake Engineering

詹旻霓(Min-Ni Jhan)

指導教授 ： 黃尹男

國立臺灣大學/工學院/土木工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.02589

摘要

臺灣位於板塊交界處，導致地震發生頻繁，因而容易造成人民生命與財產上的損失，故為了避免前述情形，房屋結構的耐震性能評估成了必要的手段之一；本研究使用美國ATC-58規範中的新一代房屋結構耐震性能評估法，其最大特點在於引入機率的概念，並採用業主與房屋使用者能理解的性能指標，以提升評估結果在應用上的方便性與普遍性。
新一代房屋結構耐震性能評估主要分為詳細評估法（非線性動力分析法）與簡易評估法（線性靜力分析法），本研究是針對簡易評估法的部分進行相關探討與分析；其是利用線性靜力分析所求得之結構反應再乘以一修正係數來預測建築物經歷地震情境下的非線性結構反應，而修正係數之公式和參數則是利用十三棟不同種類及樓層數之建物搭配不同的設計反應譜與地震歷時資料下的反應來迴歸求得，也因其相關假設與其他因素影響，導致此方法在預估彈性範圍之反應及加速度最大值反應可能有準確性較差的情況，因此提出新的修正係數計算公式，希望能改善前述方法預測過於保守或不保守之情形。
為比較簡易評估法套用規範與本研究建議之修正係數公式在預估建築物於地震下的結構反應最大值之準確度，因此使用三層樓、九層樓與二十層樓構架來進行分析與討論；結果發現，新的迴歸式能改善某些結構反應之預測成效或降低變異性，進而達到精確度的提升，但在預估彈性範圍之加速度最大值反應的部分，無論使用何種修正係數之計算方式仍無法達到最佳之估算效益。
為了解決簡易評估法於估計彈性的加速度最大值之缺陷，除了可使用非線性動力分析來解決此問題，亦可採用模態疊加歷時分析法來預測樓層最大加速度結果，其不但可達到一定之精確性，也可節省非線性動力分析所耗費的時間成本。

關鍵字

ATC-58 ； 耐震性能評估 ； 線性靜力分析 ； 非線性動力分析

並列摘要

Taiwan is located on the junction of Eurasian Plate and Philippine Sea Plate, so earthquakes occur frequently, thus cause multiple casualties and the loss of property of the people. Seismic performance assessment of buildings has become one effective tool to evaluate seismic risk of buildings. This study studies and improves the procedures for next-generation seismic performance assessment developed in the ATC-58 project in the Unites States, termed the ATC-58 procedures.
The ATC-58 procedures provide two levels of risk evaluation using nonlinear dynamic and linear static analyses, respectively, and this study focuses on the improvement of the procedures using linear static analysis, termed the simplified analysis herein. In the simplified analysis, the structural responses of a building are computed using linear static analysis and then multiplied by correction factors to predict the linear/nonlinear responses of the building subjected to ground motions with different intensity. The formulas and parameters of correction factor were developed using regression analysis on the responses of thirteen prototype buildings subjected to ground motions with a wide range of intensity. This study proposes a new formula for calculating the correction factor, and improves the accuracy of the results of the simplified procedures.
To compare the effectiveness of the correction factors recommended by the ATC-58 project and this study, this research performed a series of nonlinear response-history analyses using a three-story, a nine-story and a twenty-story moment resisting frames. The responses were compared with the predictions of the ATC-58 project and this study. For peak floor velocity, the formula of this study better predict the responses and reduce the variability in the residuals. The correction factors for both the ATC-58 procedures and this study fail to generate acceptable results for the peak floor acceleration (PFA) when the buildings are in the elastic range. This study recommends to use the modal superposition analysis to predict PFA in the elastic range.

並列關鍵字

ATC-58 ； seismic performance assessment ； linear static analysis ； nonlinear response-history analysis

參考文獻

[8] 黃尹男 (2011)，"美國新一代房屋結構耐震性能評估法"，結構工程第二十六卷第四期，中華民國結構工程協會，第59-74頁。

[2] Huang, Y., Whittaker, A., Luco, N., and Hamburger, R. (2009). "Scaling Earthquake Ground Motions for Performance-Based Assessment of Buildings." Journal of Structural Engineering, 137(3), 311-321.

[3] Federal Emergency Management Agency. (2003). "2003 NEHRP recommended provisions for seismic regulations for new buildings and other structures and accompanying commentary and maps." Report No. FEMA440, FEMA, Department of Homeland Security, Washington, D.C.

[4] Federal Emergency Management Agency. (2005). "Improvement of Nonlinear Static Seismic Analysis Procedures." Report No. FEMA 440, FEMA, Department of Homeland Security, Washington, D.C.

[5] Federal Emergency Management Agency. (1997). "NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures." FEMA273 (Provisions) and 274 (Commentary), Federal Emergency Management Agency, Washington, D.C.