NEGATIVE FRICTION COMPUTATIONAL RESEARCH OF ROCK-SOCKETED PILE BASED ON LOAD TRANSFER METHOD

The negative friction piecewise calculation model of a rock-socketed pile was established by the effective stress method, combining with the load transfer method. Then the analytical solution and the power series solution of pile body displacements and axial forces were obtained by a displacement control equation. Furthermore, the iterative calculation method used to calculate the pile shaft axial forces and the neutral position of negative skin friction resistance was proposed. Through the analysis of an engineering example and using linear fitting method to accurately describe the soil subsidence, the change curve of pile axial-forces along the pile within the scope is identical with a measured curve. The method can accurately describe the negative friction transmission process and its distribution along a pile.