Numerical Analysis on Anti-Seismic Dynamic Response of Rectangular Caisson Foundation

Based on the software FLAC3D, we set up the dynamic calculation model. By applying the horizontal (x direction) seismic waves at the bottom of the model, we simulate the earthquake action to the caisson foundation and the soil body around it and obtain the time-history curves of the acceleration, the velocity and the displacement of the key points in the model in x direction. We also obtain the rotation angle time-history curve and the relative displacement time-history curve of two key points at the bottom of the caisson foundation. Through the analysis on these curves, we know the maximum values of the acceleration, the velocity and the displacement of the top portion of the caisson foundation are 393.6 cm/s2, 75.9 cm/s, 28.5 cm, and the maximum rotation angle of the caisson foundation is 0.08°. We sure the bond of the caisson foundation bottom and the below soil layer is firm and the relative displacement is only 1.3 mm. Looked from the overall,the anti-seismic property of the caisson foundation is good. The above results provide a reliable basis for the future research on the dynamic response of caisson foundation.