Influence of large diameter deep buried pipe jacking construction on surface settlement

Abstract

Pipe jacking construction is widely used in urban construction due to non-excavation or less excavation, but the surface settlement caused by pipe jacking construction cannot be ignored. Relying on a pipe jacking project of a power tunnel in Foshan City, the law of surface settlement caused by pipe jacking construction was studied through field measurements, numerical simulations and Peck empirical formulas, and the effects of pipe-soil friction, grouting pressure and supporting pressure on the ground settlement were discussed. The results show that the lateral surface settlement caused by pipe jacking construction changes greatly within the range of approximately four pipe diameters from the axis, and the change in pipe-soil friction has a greater impact on the surface settlement within the range of approximately three pipe diameters from the axis. It has little effect on the surface settlement within the range of approximately one pipe diameter from the longitudinal ground surface to the excavation surface; the increase in grouting pressure can restrain the settlement of the surface. The surface settlement has a greater impact, and the research results can provide references for measures to control surface settlement caused by pipe jacking construction. At the same time, the measured value, simulated value and Peck's empirical formula have similar ground settlement trends and magnitudes, verifying the feasibility of numerical simulation and Peck's empirical formula in predicting surface settlement in actual projects.

Keywords

• pipe jacking construction
• surface settlement
• numerical simulation
• pipe-soil friction
• grouting pressure
• supporting pressure