The Numerical Simulation Study Of Dynamic Testing Method For The Bridge Foundation Pile

The pile of low strain reflected wave method has a number of advantages such as convenient, fast and economic, high accuracy, occupies important position in the pile integrity testing and has more rapid development in recent years. However, in the current projects, there are still some difficulties at the location and quantitative analysis of pile defects. Based on the current research of low strain reflection wave method, this paper mainly done the following works:First create the ideal state of elastic wave propagation in the bar one-dimensional wave theory of equations, use the D’Alembert general solution, draw elastic wave propagation in the upstream wave velocity and downstream wave velocity solutions, by discussing the relationship between the rod free end and fixed end conditions contrast elastic wave propagation process.Based on elastic wave propagation in one-dimensional medium, the wave equation and analytical solution, combined with the soil around the pile damping situation, use of the dominant analysis of ABAQUS in geotechnical engineering finite element simulation software ABAQUS/Explicit, simulate the complete friction piles containing soil around the pile and complete end bearing piles, compare the simulated time-domain curve perfect pile curve detected in the actual project with obtained using the software simulation of elastic wave propagation in three-dimensional pile.come to this approach is feasible.The numerical simulation software ABAQUS/Explicit is used to establish the pile-soil interaction under the conditions of expanding pile mode, by changing the soil around the pile or a parameter (Elastic modulus, soil density, damping coefficient, the scale of expanding) of pile, come to the various parameter changes in the time domain reflection wave velocity curve, by fitting the equation, find out the law and reach a conclusionThe establishment of shallow defects in the actual project pile three-dimensional model, compare with the bulk pile speed time-domain curve detected on the site. Concluded that the bulk pile shallow expanding pile of shallow-domain waveform changes in a fully non-essential reason.