Soil Damping Effects on Integrity Test of Piles

The effects of surrounding soil on pile integrity test results are still not precisely quantified despite its influence on test output. It is usually difficult to assess the integrity of piles socketed in hard soil strata due to soil damping effects. A method of calculating soil damping effects on stress wave force and velocity values during pile integrity test is presented. Theoretical model based on numerical solution of wave equation was formulated. This model incorporates soil resistance effects on wave propagation in piles. Results generated from the proposed model was compared with PIT-S software, which simulates low strain waves propagation in piles, assuming pile cast in very dense granular soil. The generated Force-Velocity curves were found to be similar comparing both methods; however, some variations were observed at pile toe due to the different procedures used for soil reaction estimation. Furthermore, the model produced results were compared with real in-situ pile integrity test and PIT-S results. The model had showed better prediction of pile toe received signal compared to PIT-S software.