Research on Uplift Static Load Test of Large-Diameter Steel Pipe Pile Based on Mechanics

Combined with the uplift static load test of large-diameter steel pipe pile in Xiangshan Port bridge of Ningbo, make analysis of Q-s curve and s-lgt curve, axial force distribution curve and unit shaft resistance, revealing the uplift characteristic of the steel pipe pile. The analyses show that the uplift steel pipe pile is pure friction pile, the uplift load is decreased downward through the axial force of pile body, the shaft resistance gradually plays from top to bottom and play completely in the upper soil. Moreover, it has used hyperbolic model to fit the measured Q-s curve by Matlab software, and the fitting precision is high. Then make the hyperbolic model non-dimensional, and attempt to predict ultimate bearing capacity using the maximum curvature point of the non-dimensional hyperbolic model, to get some mechanical characteristic.