Torsional Response of Piles

An analysis is described for the determination of the response of a single cylindrical pile subjected to torsion. The accuracy of the analysis is checked against existing solutions and found to be satisfactory. Parametric solutions for the torque-rotation relationship for the pile head are presented, for both a uniform soil and a soil in whih shear modulus and pile-soil adhesion increase linearly with depth. The results of a series of model tests on piles in clay are described in which the axial and torsional responses of the piles are investigated. The tests indicate that both the working load and ultimate behavior of a pile subjected to torsion may be reasonably predicted from the results of axial load tests or vice versa.