應用多項式摩擦單擺支承於橋梁之設計

王濬暉(Chung-Whui Wang)

指導教授 ： 李姿瑩

國立中央大學/工學院/土木工程學系/碩士(2015年)

摘要

傳統摩擦單擺支承(Friction Pendulum System)其隔震週期為定值，在具長週期脈衝特性之近域地震下易與震波產生共振反應，折損其隔震效用；為了改善此缺點，發展出一具變頻特性之新型摩擦單擺支承：多項式摩擦單擺支承(Polynomial Friction Pendulum Isolator，PFPI)，其滑動曲面為一六次方多項式函數，利用支承回復勁度遞減之軟化段降低結構加速度反應，及利用支承回復勁度遞增之硬化段抑制結構位移反應。經研究已證實PFPI可發揮其變頻特性，於近遠域地震中皆可發揮良好的隔震效用。
過去研究採用最佳化搜尋流程：混合式搜尋法(PSO-SA)，尋找PFPI之最佳支承參數，隨著搜尋流程訂定之目標函數的不同，搜尋出之支承最佳參數有相當大的變化，輸入不同震波亦會搜尋出不同的最佳支承參數，使設計者在實際設計時難以進行。本研究嘗試將PFPI隔震橋樑設計與台灣現行公路橋梁耐震設計規範作結合，設計者可根據場址條件查閱公路橋梁耐震設計規範，遵循一簡單的流程進行PFPI隔震橋梁支承設計，最後並比較使用此流程設計出之隔震橋梁與無隔震橋梁於地震下之反應。結果顯示經由此一流程設計出之PFPI隔震橋梁亦可有效發揮良好隔震效果。
關鍵詞：變曲率隔震支承、變頻隔震支承、公路橋梁耐震設計規範。

關鍵字

變曲率隔震支承 ； 變頻隔震支承 ； 公路橋梁耐震設計規範

並列摘要

Since the isolated period of traditional Friction Pendulum System (FPS) is a constant. The potency of FPS will reduce by getting resonated from near-field earthquake with long period of impulse. To improve this defect, a new kind of various-frequencies seismic isolator call Polynomial Friction Pendulum Isolator (PFPI) has been developed. The sliding surface of PFPI is defined by a sixth-order polynomial function. The restoring force processes a softening phase and a hardening phase. The restoring stiffness is decreasing in softening phase to mitigate the acceleration response, and the restoring stiffness is increasing in hardening phase to reduce the displacement response. It has been proven that PFPI can reduce the response of structure efficiently both in far-field and near-field earthquake
The parameters of PFPI are developed by a hybrid PSO-SA procedure (Particle Swarm Optimization, PSO and Simulated Annealing, SA ) in fore research. It is hard to use for designer in realistic since the optimal parameters is various by setting the different object function in optimal procedure or inputting different ground motions. This study is trying to combine the design of PFPI bridges with the current Seismic Design Provisions and Commentary for Highway Bridge code in Taiwan. Designers can follow a simple process to design the bridge with PFPI according to the local site condition. Finally, compare the response of the PFPI bridges designed by this simple procedure to the non-isolated bridges. The results show that the PFPI bridges designed by this simple procedure can also reduce the seismic response effectively

Keywords: variable-curvature seismic isolator, various frequencies seismic isolator, Seismic Design Provisions and Commentary for Highway Bridge.

並列關鍵字

Variable-curvature seismic isolator ； Various frequencies seismic isolator ； Seismic Design Provisions and Commentary for Highway Bridge

參考文獻

方燕甄 “考慮垂直效應之多項式摩擦單擺支承之分析與設計”，國立中央大學土木系碩士論文(2011)，指導教授：莊德興。

莊玟珊 “PSO–SA 混合搜尋法與其他結構最佳化設計之應用”，國立中央大學土木工程學系碩士論文(2007) ，指導教授：莊德興。

Fukushima, Y., Irikura, K., Uetake, T., and Matsumoto, H. (2000). “Characteristics of observed peak amplitude for strong ground motion from the Hyogoken Nanbu (Kobe) earthquake.” Bulletin of the Seismological Society of America, 90, pp.545-565.

Lu, L. Y., Lee, T. Y., Juang, S. Y., and Yeh, S. W. (2013), “Polynomial friction pendulum isolators (PFPIs) for building floor isolation: An experimental and theoretical study” Engineering Structures, No.56, pp.970-982.

Pranesh, M. and Sinha, R. (2000). “VFPI: an isolation device for aseismic design.” Earthquake Engineering and Structural Dynamics, 29(5), pp.603-627.