Dynamic Response and Blast-resistance Analysis of Double Thick Subway Tunnel Subjected to Blast Loading Within One Side of Tunnel

This article investigated on the dynamic response of double track subway tunnel subjected to blast loading within one side of tunnel, and analyzed the blast resistance property of the subway tunnel by choosing foamed aluminum as the blast protection measure. An integral calculation model comprising of two -way subway tunnel and its neighboring finite stratified soil and the far-field semi-infinite soil was established by using the coupled finite and infinite element methods to investigate the interaction between soil and structural dynamic force. The finite element model of soil was established on the basis of geological exploration data of actual subway engineering. Through numerical simulation for the actual subway engineering and the comparative analysis on the calculated results, this article revealed the influence of the explosive overpressure, the embedded depth and the spacing interval of the double track tunnel, and the soil condition around the tunnel on the stress field of the tunnel lining. The results show that the foamed aluminum is of desirable cushioning effect and energy absorption property, which could be used as an efficient measure to improve the blast-resistance ability of the subway tunnel.