Analysis of 3 D Effects in Low Strain Testing of Pipe Pile

Abstract:

A real three dimensional (3 D) pile soil model under cylindrical coordinate system is established in order to get a deep understanding of low strain integrity testing of pipe pile. According to elastodynamic equations, boundary conditions and initial conditions, the definite solution of this problem can be obtained. Then, based on the staggered grid finite difference method, the transient dynamic responses of a pipe pile subjected to transient vertical loading are discussed. Not only the velocities of different angles at pile top are obtained, but also the testing curves are presented, which directly reflects the 3 D effects of wave propagating in the pipe pile. Finally, the accuracy and feasibility of the numerical method are verified via comparing with the experimental data. In practice, especially under the conditions that the analytical solution of 3 D elastodynamic equations cannot be derived, the numerical solution has certain guiding significance.

Key words:3 D pile soil model; staggered grid; finite difference method; 3 D effects; experimental analysis