Influence of jacking open-ended tubular piles on bearing behavior of existing in-service piles

Based on the classical pile side resistance formula and the round hole expansion theory, the effect of the implantation of new pipe piles on the bearing characteristics of in-service pile was calculated by considering the soil pressure coefficient, the growth rate of the soil plug, the plastic radius of the expansion hole and so on. Comparing the software and theoretical calculation results of finite factors, the effect of inter-pile soil extrusion caused by pipe piles is induced, so that the resistance on the side of the serving pile increases in a certain depth range, and the longer the pile length and the smaller the pile spacing, the more obvious the contribution is. The distance between the new pile and the in-service pile is less than 3 times the pile diameter, a local pile effect is formed so that the settlement of the top of the pile increases, when the pile works together. The distance is greater than 6 times the pile diameter, and the pressure of the pipe pile will has less effect on the existing pile side resistance and the group pile co-operation effect. © 2021, Zhejiang University Press. All right reserved.