Analytically-based simplified formulas for circular tunnels with two liners in viscoelastic rock under anisotropic initial stresses

摘要

The time-dependency in tunneling is mainly due to the theological properties of the rock and tunnel construction processes. Rock rheology results in tunnel convergence and pressures acting on the liners increase with time, both of which are critical parameters to be determined for tunnel and liner designs. In this study, a general analytical solution was derived and the simplified formulas were suggested based on the analytical results, which allow for the predictions of liner pressures and tunnel convergence. The anisotropic initial stresses and rock viscoelasticity, as well as the primary and secondary liners and their installation times were all accounted for.