中文摘要：

以京沪高铁沿线简支梁桥桥墩为试验原型，对6个缩尺比为1：5的桥墩试验模型进行低周反复荷载试验，并采用改进的刚度退化模型、Park-Ang模型和Mander-Cheng模型3种地震损伤模型对桥墩试验模型的损伤过程进行评估，研究不同损伤模型对高速铁路桥墩损伤的评估效果。研究表明：Park-Ang模型不能有效评估剪切破坏型桥墩的损伤状态，Mander-Cheng模型的评估结果离散性较大，而改进的刚度退化模型可以较好地评估高速铁路桥墩的损伤状态。结合桥墩试验模型的低周反复荷载试验结果，将高速铁路桥墩的损伤程度划分为基本无损伤、轻微损伤、中等损伤、严重损伤和完全损坏5个等级，并给出各损伤等级相应的损伤指数范围，各等级损伤指数的临界值分别为0，0．25，0．5和1。

英文摘要：

Six one-fifth scale pier models were tested under low cyclic loading, whose prototypes were piers of simply supported beam bridges along Beijing-Shanghai high speed railway. The damage processes of test models were evaluated using the modified stiffness degradation model, Park-Ang damage model and Man- der-Cheng damage model, and the effectiveness of different damage models on the damage assessment of high speed railway bridge pier was studied. The results show that the Park-Ang model cannot effectively e- valuate the damage state of shear failure type pier. The evaluation results calculated by Mander-Cheng model are of higher discreteness. However, the modified stiffness degradation model can better evaluate the damage state of high speed railway bridge pier. The damage degree of high speed railway bridge pier can be classified as no damage, minor damage, moderate damage, severe damage and complete damage according to the results of low cyclic loading tests of pier models. The corresponding damage indices for each damage degree are given and the critical values for each damage degree are 0, 0.25, 0. 5 and 1 respec- tively.