Numerical Analysis of Effect of Jacked Pile on Performance of Buried Pipes

To analyse the influence of the driving process of jacked piles on the performance of adjacent buried pipes via the planar finite element method numerical simulation based on the displacement penetration method and achieve the dynamic pile driving process by establishing the pile-soil and pipe-soil contact surfaces and applying the displacement load at the top of the pile, comprehensive analysis was carried out to investigate the effect of the pile penetration depth, pile diameter, horizontal centre distance between the pile and buried pipe, and buried depth, on the performance of buried pipes during pile driving. The calculation results showed that when keeping other parameters identical and first increasing the horizontal distance, caused a decrease in the horizontal displacement, radial deformation, and stresses of pipes. The maximum horizontal stress of the soil surrounding the pipes is 1.5 times that of the soil without pipes. Secondly, with the increase in the pile penetration depth, there exists a critical penetration depth, after reaching it, the horizontal displacement of pipes increases significantly, then somewhat decreases, and finally becomes steady. Moreover, the maximum horizontal displacement of pipes can be reached when the penetration depth is equal to 2 times the buried depth of the pipe. Thirdly, increasing the buried depth of the pipe results in remarkable change in the deformation and mechanical performance of the pipes. For a buried depth of 5 times the diameter of pipe, the maximum horizontal displacement of the pipes reduced by 27.8% when the pile diameter decreased by 25%. This implied that reducing the diameter of jacked piles can considerably weaken its effect on buried pipes.