Simulating the post-installation residual stress in jacked and driven piles

Residual stress is a product of the irretrievable elastic deformation of a shaft penetrated into friction material during a process of compression and rebound. Its effect could be very important for long piles installed in stiff soils. The insight of energy conservation universally sheds a light on simulating the residual stress in a rational and analytical way that may not involve excessive numerical efforts. Assuming that the interface shear and end-bearing behaviors are ideally elasto-plastic, the presented framework gives a simplified form of solution to the residual stress locked in preformed piles. This solution is novel as the influence of installation method is taken into consideration by introducing the number of loading cycles. Interpretation of full-scale load tests on jacked and driven piles has demonstrated that the new approach is able to simulate the field measurements.