土-承台动力相互作用对砂土场地桩基桥梁地震反应的影响

在桩基桥梁的地震反应分析中，桩-土动力相互作用是个重要的问题，而对于采用低桩承台基础的桥梁，承台埋在土面以下，还存在土与承台之间的动力相互作用。目前，地震反应分析中一般不考虑土-承台动力相互作用的影响，相关研究也很少。为此，利用OpenSees有限元分析程序，基于p-y曲线建立了土-结构一体化桩基单墩模型，选择40条实际岩石场地地震记录作为输入，开展了考虑土-承台动力相互作用的桩基桥梁地震反应分析。结果表明，考虑土-承台动力相互作用后，结构的基本周期会减小，墩底曲率会明显增大，桩顶曲率会大幅减小，但墩顶位移的减小可以忽略。

Influence of Soil-Base Slab Dynamic Interaction on Seismic Response of Pile Foundation Bridges in Sandy Soil Site

Soil-pile dynamic interaction is an important issue in the seismic response analysis of pile foundation bridges. For a bridge with the low-pile base slab foundation, the base slab is buried below the earth surface, and there is also dynamic interaction between soil and base slab. At present, the influence of soil-base slab dynamic interaction is generally not considered in seismic response analysis, and is rarely studied in the literature. Therefore, based on the p-y curve method, a soil-structure integrated pile foundation single-pier model is established by using OpenSees finite element analytical procedure. 40 actual rock site seismograms are selected as input to carry out the seismic response analysis of pile-supported bridge considering the soil-base slab dynamic interaction. The results show that the basic period of structure will decrease after considering the soil-base slab dynamic interaction, and the curvature of pier-bottom section will obviously increase and the curvature of pile-head section will greatly decrease, but decrease of displacement at the pier top can be neglected.