Study On The Characteristics And Influence Factors Of Horizontal Dynamic Response Of Pile Foundation Based On FLAC^3D

This paper uses the FLAC3 D software to do the numerical simulation of the single pile and pile group test mainly based on the shaking table test of pile foundation in liquefied soil. On this basis, this paper studies the influencing factors of the lateral dynamic response characteristics of pile groups and achieves many achievements.First of all, this paper analyses and introduces the calculation principle and calculation process of FLAC3 D software, and its application in pile foundation engineering.Secondly, this paper introduces the shaking test, including the organization and arrangement of the test, the data acquisition system, test samples,test conditions and so on.Then, this paper establishes the numerical model of single pile through the FLAC3 D software based on the shaking table test and then compares the simulation results with experimental results. The research shows that the acceleration and displacement of tables and piles cap increase linearly with the increase of the sine wave peak acceleration input in the non liquefied simulation, while that the lateral dynamic response of pile foundation is obvious with the increase of the sine wave peak acceleration input especially when the sandy soil is liquefied in the liquefied simulation, also that the numerical simulation results agree well with the experimental results. The simulation on the condition of seismic wave input can also get the same conclusion.Moreover, this paper completes the numerical simulation of pile group and compares the simulation results with experimental results based on the shaking table test. The research shows the laws of the acceleration and displacement of group piles cap are similar to those of single pile in non liquefied simulation, but that there are differences in the magnitude, while that the sandy soil is liquefied and the lateral dynamic response of pile group reaches the maximum when the acceleration is 0.15 g in liquefied simulation, but that it is not more significant than single pile, also that the numerical simulation results agree well with the experimental results. The simulation on the condition of seismic wave input can also get the same conclusion.Finally, this paper studies the factors of the lateral dynamic responses characteristics of pile groups. The research show that the acceleration curves and displacement curves of pile changes from to the beginning steep fall type to the gentle type, while that the proper increase of pile spacing and the number of piles can effectively improves the overall stability of the structure.