Correlation between Pile Displacement from Pile Load Tests and FE Modelling: Case Study of Piles in Cawthorne Channel Area in Nigeria

Abstract

Pile load static tests are used to confirm that a pile would not exceed a prescribed displacement at service or ultimate limit load. In this work, 600mm diameter steel piles were driven to 30m depths at the project site in the Niger Delta region of Nigeria. The relationship between pile displacements obtained from field pile load tests on these driven piles and those obtained from a finite element (FE) program, PileAXL, was studied. It was observed that for loads lower than the elastic limit of the soils at the pile toe, the FE program was able to accurately predict the displacements obtained from pile load tests. However, as the test loads on piles increased, the FE program was not able to accurately predict the displacements obtained from the pile load tests. This suggests that as significant plasticity sets in the end-bearing pile spring in the FE program, a more rigorous end bearing nonlinear spring would be required to model the load-displacement behavior of piles. This paper aims at presenting a technical reference to show that pile load test results can be easily validated using simplified FE models at low service loads using simplified nonlinear springs to model pile shaft interaction and end-bearing displacements.

Keywords

• pile load test
• fe
• displacement
• modelling
• validation