饱和土–结构动力相互作用分析中地震动输入方法研究

Wave input method for saturated soil-structure dynamic interaction analysis

为解决地震荷载下土–结构相互作用研究中地震动的输入和半无限地基的模拟两个关键问题,阐述并比较了不同地震动输入方法,如波动法、人工边界子结构法和DRM方法。相对于其他地震动输入方法,DRM方法将地震动外源激励转化为内源激励问题,且在考虑材料非线性时,不需要对整体模型进行非线性分析,提高了模型的计算效率和准确性。基于区域缩减法DRM提出了针对饱和土多孔介质的地震动输入方法,用数值算例验证了该方法的有效性。

In the process of establishing the numerical model to study the soil-structure dynamic interaction problem, the wave input method and the simulation of wave propagation behavior within the semi-infinite medium are critical. There are many wave input methods, such as the wave method, method of substructure of artificial boundary and domain reduction method. The domain reduction method has some advantages over the other methods. On one hand, the earthquake input motion is converted to the source excitation motion within the model, thus the absorbing boundary works better. On the other hand, the size of the numerical model is reduced. The domain reduction method is used for saturated soils through the similar formulation, and the effective forces and effective flow are derived. The proposed method is verified by a simple numerical test.