The Comparison of Dynamic Response of Lined Tunnels under Internal Loading between Two Surrounding Media: the Elastic Medium and the Saturated Porous Medium
Abstract：Considering the dynamic interaction between lining and soil and the difference in dynamic response to the internal blast load between different soil media surrounding the lined tunnel, the dynamic responses of lined tunnels subjected to an internal blast load in the saturated medium and the elastic medium are compared and studied. First, the porosity of saturated medium surrounding the lining structure is set as n=0, which is degenerated into the elastic medium, and the solution to the dynamic response of saturated medium is then degenerated into the solution of elastic medium. This degenerate solution is completely consistent with the existed solution to the dynamic response of elastic media surrounding the lined tunnel. Subsequently, the dynamic responses of lined tunnel in saturated soil with different porosities and ideal elastic medium are computed and compared. It is found that (a) compared with the elastic medium, the dynamic response of lined tunnel in saturated medium is larger, and the attenuation of the response along the axis is faster; (b) the dynamic response at the inner surface of lining in the saturated medium increases gradually with the decrease of porosity, meaning that the trends of time-history curves of displacement and stress at the inner surface of lining in the saturated medium are similar to those in the elastic medium as the porosity decreases.
2019, Vol. 40 
