Researches on the Excavation Disturbance of Shield Tunnel in Sandy Cobble Ground

The sandy cobble ground has loose structure, uneven particle size, and random distribution characteristics, which may lead to the local collapse of ground. This paper carried out field tests based on the project of Luoyang urban rail transit. For this, the surface settlement, pore water pressure, and earth pressure in the test section were measured. The excavation disturbance and influence range on the soil layer in each stage of earth pressure balance shield tunneling were studied. Meanwhile, based on the key construction elements in sandy cobble ground, a numerical simulation method was proposed based on shield construction parameters. The disturbance characteristics of deformation, seepage action, and stress state of the sandy cobble ground during shield construction were obtained through numerical calculation. The rationality of the simulation results was verified by the measured tests. The results showed that the measured data were in good agreement with the simulation results. The research results provide a calculation method for predicting the soil disturbance in the earth pressure balance shield construction in a sandy cobble ground.

Automated summary

This study conducted field tests and numerical simulations to investigate the soil disturbance in earth pressure balance shield construction in sandy cobble ground, and proposed a calculation method.