Numerical Study on the Effect of Grouting on Long-Term Settlement of Tunnels in Clay

Abstract

Abstract. The long-term settlements over tunnels can be rather significant, particularly when tunnels are embedded in soft and compressible soils. The influence of grouting on the evolution of long-term surface settlement, as well as ground loss, is simulated by imposing prescribed volumetric strain on the disturbed area around the tunnel due to shield tunneling. The volumetric strain could be detected from the grouting ratio of grouting volume and the volume of the physical gap of shield tunnel. Finally, some conclusions are drawn from the numerical simulations.

Study on Numerical Analysis of Tunnel Longitudinal Uneven Settlement Base on Elastoplastic Theory

“…The influence of the stratum uneven settlement can not be ignored in the location where the nature of soil is dramatic changes at the bottom of the tunnel, and the position where the thickness of covering soil is rapid changes. At present, for the theory models to analyze the tunnel structure, many researchers have done many study by site tests [1], theoretical analysis [2], numerical imitation [3] and other tools [4], to solve those problems such as why and how to eliminate the vertical differential settlement of tunnel, tunnel longitudinal stiffness, the model of interaction between tunnel and soil, and so on. Huang [5] proposes a 3d shell spring model using rectangular flat shell element to simulate the lining, and using the spring element to simulate the effect of joint segment.…”