On stability of shallow tunnel by model test and numerical simulation

Abstract

The geometry and mechanical properties of the discontinuity as well as opening dimensions are the govern parameter in the instability of the shallow underground tunnels. Presented research is relate to the analyses such structure using small scale experimental and numerical models. In the tested models beddings dip varies from 0 to 90°. Layer thickness is considered 16 mm. The tunnel width and height are considered 10, 12, and 14 times as big as the bedding thickness. Also, the joint spacing is one to two times as big as the bedding thickness. Based on the 72 model results the extension of the collapsed zone measured and its variation analyzed. Among other considered parameters, the bedding dip has notable effect on collapsed zone for shallow underground spaces.