Seismic behavior of vertical shaft in a multi-layered soil

Dynamic responses of a vertical shaft subjected to seismic loads in a layered soil were investigated by using a three-dimensional Finite Element (FE) approach. The emphasis was on quantifying the load distribution and deformation of the vertical shaft under earthquake loadings. The commercially available FE code ABAQUS was used to perform a series of dynamic parametric analyses. A comparison between the dynamic and the pseudo-static ( Response Displacement Method, RDM) method has also carried out for the specific structure geometry, including three cases of ground condition and three earthquake waves. It was found that the dynamic behavior of the vertical shaft was significantly influenced by the soil stratigraphy and input motion. Based on the dynamic analysis results, the maximum values of shear force and bending moment occurred near the interface between the soil layers. And also pseudo-static approach results are in a good agreement with dynamic analysis results. The deformation of vertical shaft was highly influenced by the amplitude of earthquake for the case of the vertical shaft constructed in a multilayered soil.