桩土相互作用是桥梁抗震研究中的难点，计算模型的选用和参数确定直接影响计算结果的精度，为此，提出一种改进P日d曲模型及其参数的确定方法，井以此模型采用动力反应时程方法对国外某桥进行了实例计算分析，旨在为考虑桩土相互作用问题提供一种适舍工程应用的分析方法。

This paper proposes a simple lattice model for collapse analysis of RC bridges subjected to earthquakesby using the extended distinct element method (EDEM). In the model, a concrete element consistsof lumped masses connected to one another by springs, and a reinforcement bar is represented by adiscrete model or an integrated model. The proposed lattice model is simple but its parameters arereasonably defined. It has fewer element nodes and connecting springs, which will be of benefit byshortening the CPU time. The processes to determine the initial stiffness of concrete and steel springs,the parameters of the constitutive model and the fracture criteria for springs are described. A re-contactspring model is also proposed to simulate the re-contact of the concrete after fracture of springs; anda general grid searching method is used to decrease the CPU time for judging re-contact after fracture.The lattice model is assessed by numerical simulations and experiments. As an application, a damagedsingle-column pier subjected to the Kobe Earthquake in 1995 is analysed by EDEM with the proposedmodel. The simulation results indicate that the proposed model predicts well qualitatively the collapseprocess of RC bridges. Copyright

重泥水トィゾナ液c二加重材（バティト）キ加元制成ゐたれ高粘性，高比重れ特性老有寸否材雷力；安定教掖体ゆゅや。二机老TLDろ用よょい，高比重商品粮スロッツグン夕少减衰；TLD小型化制振劾果の向上力；可能生やむみ。本研究ぽは，非ントニ流体わゐろ重泥水の减衰特性乏把ょよ握後，重泥水TLD0举勤老模型夷骏，等佃减衰老撙入L广二非稼形波勤理揄解析めゐれ高橘脚施工畴の鲴管柱加振寞骏ひりり梭亏しげのと寸L秸果，重泥水TLDけは法TLD④2～3倍0减衰付加性能老有老碓恐したまた，重泥水TLDの简易段卦手法务提案した。