由於台灣之特殊地理位置與地形，使得島內橋梁於雨季中經常飽受洪水衝擊，此外，人為與天然的災害造成河道改變、河床沖刷、以及基礎淘空，大幅地降低橋梁之耐震能力。本文研究基礎裸露之鋼筋混凝土橋梁的耐震行為，使用LS-DYNA有限元素分析軟體，建立並模擬不同橋柱高度、以及不同基礎裸露深度下混凝土橋梁之非線性分析模型，其中，樁基土壤互制結構以彈簧元素模擬，並分別採用擬靜態側推與動態歷時分析，探討基礎裸露橋梁之抗震能力與倒塌機制。並利用ATC40(Applied Technology Council) 內之容量震譜性能評估方法，評估與調查基礎裸露鋼筋混凝土橋梁之抗震性能。;Due to the special geographical location and topography of Taiwan, bridges often suffer from flood impacts in the rainy season. In addition, natural and man-made disasters cause alterations of the river path, riverbed erosion, and basis underrun, reducing the seismic capacity of bridges. This research discusses the seismic performance of reinforced concrete bridges with exposing pile foundations by using LS-DYNA finite element analysis software. Nonlinear numerical bridge models with different height and exposed depth of bridge piers are established. Soil-structure interactions are modeled using spring element. The seismic performance of bridges are investigated using pushover analysis and dynamic analysis. The capacity spectrum method suggested in ATC-40(Applied Technology Council) is also implemented for evaluation and investigation of reinforced concrete bridges with exposing pile foundations.
