Quasi-static interaction between pipe piles and multilayered saturated soft soils with a fractional viscoelastic model

Abstract

This paper proposed an efficient method for analyzing the quasi-static interaction between the pipe pile and multilayered saturated soft soils. A pipe pile is simplified into a 1D compression bar and then discretized into a number of elements. The interaction forces on the inner and outer interfaces between the pipe pile and soft soils are integrated by the trapezoidal rule. Based on the precise integration solution of multilayered saturated soft soils with a fractional viscoelastic model, the flexibility matrix of the soil under a vertical annular load is formed. According to the force equilibrium and displacement compatibility on the pile–soil interfaces, the coupling interaction equations are established and solved. The correctness of the proposed method is verified by comparing the calculated results with those of the existing literature. Numerical examples are discussed to evaluate the effects of the viscoelasticity of soils, pipe wall thickness, pile length–radius ratio, pile–soil modulus ratio, and soil stratification on the interaction between pipe piles and soft soils.