中文摘要：

为了快速准确地评估受地震影响的梁式公路桥的破坏状态，以朱美珍提出的震害经验统计回归方法为基础，选取更为合理的梁式公路桥震害影响因素，基于唐山地震和汶川地震中部分梁式公路桥震害资料，采用最小二乘法回归得到新的震害影响因素系数，建立了一个改进的梁式公路桥震害评估方法．改进后的方法与原方法相比，最大的区别是综合考虑场地类别和地震烈度2个因素，来代替原方法中有关液化和边坡失稳对桥梁的影响．在算例分析中分别采用朱美珍方法和改进的评估方法对汶川地震中部分桥梁进行震害评估，经过与实际震害对比，初步验证了改进方法的准确性．

英文摘要：

To estimate seismic damage of highway beam bridges quickly and accurately, influence factors of the seismic damage were more reasonably reselected in an improved methodology based on Zhu Mei- zhen＇s empirical methodology. The least squares method was used to analyze the data of partial bridges in Tangshan earthquake and Wenchuan earthquake. The improved methodology was formed with new regression coefficients of the influence factors. The main difference between the improved and original methodologies is that site classification and seismic intensity are considered together to take place of the influence factor of liquefaction and instability of side slope that are taken into account in original methodology. By using both the improved and original methodologies, some highway beam bridges in Wenchuan earthquake were estimated. Results show that compared with the real seismic damages, the improved model is preliminarily validated to be more accurate.