Behavior of ACIP Piles in Tension and Compression in Very Dense Sand: Load Test and FEM Analysis

Abstract

The behavior of ACIP pile under axial loading in very dense sand was studied by conducting a full scale load test on an instrumented ACIP pile which was designed to support a highway bridge. A load test was performed on a 760 mm (30 in.) diameter and 10 m (33 ft) long ACIP pile to verify its design capacity of 800 kN (92 tons). The loading frame was supported on 8 reaction ACIP piles with a diameter of 460 mm. The pile was loaded to over 350% of the design load. The test pile was instrumented using load cell and axial vibrating wire strain gages at four levels and lateral vibrating wire strain gages at two levels. The reaction pile was instrumented using vibrating wire strain gages at three levels. The load-settlement and load transfer relationships of the piles were investigated based on the load test and was modeled using the finite element code PLAXIS. Development of skin friction in the load test pile and the reaction pile in the very dense sand was also investigated.