Study On Damping Of Pile-Soil Interaction In Quantitative Analysis Of Defects

It is a difficult problem that how to detect the pile integrity exactly and quickly in quantitative analysis of pile defects. As a problem unsolved so far, many scholars have been probing into it .To solve the problem, following researches have been done.Instantaneous response analytic equations of the integrated pile are obtained from the model of pile-soil interaction. Instantaneous response analytic solutions in homogenous soil are obtained along the pile by solving the analytic equations using separation of variables. The degradation of stress wave along piles is analyzed on the solution by a Matlab programming, which supply to the theory basis for the following laboratory experiments.The analytic solution of impulse force impulsion in low-strain experiment is obtained by the elastic collision theory. Based on the solutions the relationship between hammer impulsion and parameters are analyzed. It is obtained that the length of pile in model experiments by analyzing the relationship between the natural frequency of pile and the operating frequency of sensor.Laboratory tests of pile-soil interaction at low-strain have been conducted to determine the damping coefficient. The correlation between the damping coefficient and overburden press of strata around pile is established. The correlation is combined with above analysis method to establish the model quantitatively analyzing the defects of piles.It is substituted into the quantitative analyzing model of the defects piles to verify the experimental results that correlation between the damping coefficient and overburden press of strata around pile.