A NEW FORMULA FOR THE TOE RESISTANCE OF A HELICAL SCREW PILE CONSIDERING THE DIFFERENT LOAD SHARING BEARING MECHANISM AT THE CLOSED END AND THE HELIX

Abstract

The authors conducted vertical loading tests on a model screw pile in a calibration chamber where the different mechanism of toe resistance mobilizing at the closed end and helical screw was in focus. Layered sand deposits were prepared in two different densities concerning relative position of the pile toe and the thin layer around it. A new formula to evaluate the toe resistance of a screw pile is proposed based on the test results. The formula shows fairly good applicability to estimate the toe resistance of full-scale piles by taking different soil modulus at the closed end and helical screw.