Abstract Large-scale shaking table tests were conducted for tunnel models with different stiffnesses in a liquefac? tion soil layer, and the effect of tunnel stiffness on the surrounding liquefiable foundation soil was analyzed by comparing the pore water pressure of the soil around the tunnel and the acceleration time history and its Fourier frequency amplitude spectrum and strain of the tunnel structure. The results show that the larger the stiffness of a tunnel structure, the larger the constraint to the surrounding soil layer and the smaller the acceleration of the soil layer nearby and the greater the influence on the shape of the acceleration Fourier spectrum curve. The laws of the acceleration amplification coefficient varying with the soil layer depth are different under different relative stiffnesses of the soil-tunnel structure. The surrounding soil layer is more inclined to be liquefied when the stiffness of the tunnel is small, and the influence of tunnel stiffness on the development law of the soil layer′s pore pressure is large. The shallower the soil layer, the faster the dissipation of the pore pressure, and the smaller the tunnel stiffness, the more likely it is to yield to the movement of the surrounding soil layer.
Abstract：
Large-scale shaking table tests were conducted for tunnel models with different stiffnesses in a liquefac? tion soil layer, and the effect of tunnel stiffness on the surrounding liquefiable foundation soil was analyzed by comparing the pore water pressure of the soil around the tunnel and the acceleration time history and its Fourier frequency amplitude spectrum and strain of the tunnel structure. The results show that the larger the stiffness of a tunnel structure, the larger the constraint to the surrounding soil layer and the smaller the acceleration of the soil layer nearby and the greater the influence on the shape of the acceleration Fourier spectrum curve. The laws of the acceleration amplification coefficient varying with the soil layer depth are different under different relative stiffnesses of the soil-tunnel structure. The surrounding soil layer is more inclined to be liquefied when the stiffness of the tunnel is small, and the influence of tunnel stiffness on the development law of the soil layer′s pore pressure is large. The shallower the soil layer, the faster the dissipation of the pore pressure, and the smaller the tunnel stiffness, the more likely it is to yield to the movement of the surrounding soil layer.
.Shaking Table Test for a Tunnel Structure with Different Stiffnessces in a Layer of Soil Liquefaction[J] MODERN TUNNELLING TECHNOLOGY, 2018,V55(4): 97-105
2018, Vol. 55 