Dynamic Analysis of a Concrete-Cored Deep Cement Mixing Pile under Horizontal Dynamic Loads

Abstract

Concrete-cored deep cement mixing (DCM) pile is a novel type of pile foundation, and its lateral dynamic response analysis has great practical significance. Based on the elastic dynamic theory, this study investigated the lateral dynamic response of a concrete-cored DCM pile in the single-phase viscoelastic soil using theoretical deduction and parametric analysis. Considering the special structure of the concrete-cored DCM pile, the lateral vibration equation of the concrete-cored DCM pile is first established with mechanical equilibrium, and then the dynamic behavior of the soil around the pile is described using the existing governing equations of single-phase soils. Subsequently, the solutions for the dynamic impedances at the pile top are deduced after a series of rigorous theoretical derivations. Finally, the influence of the pile and soil parameters on the dynamic impedances at the pile top is studied using calculation examples and parameter analysis. The results reveal that the radius of the concrete-cored DCM pile obviously affects the dynamic impedances at the pile top. Enhancing the elastic modulus of the concrete-cored DCM pile is beneficial for augmenting the dynamic impedances at the pile top. An improvement in the soil density will increase the stiffness factors of the dynamic impedances at the pile top but will reduce their damping factors.