Kinematical analysis of highway tunnel collapse using nonlinear failure criterion

YANG Xiao-li(杨小礼), YANG Zi-han(杨子汉), PAN Qiu-jing(潘秋景), LI Yu-lin(李育林)

(School of Civil Engineering, Central South University, Changsha 410075, China)

Abstract:For different kinds of rocks, the collapse range of tunnel was studied in the previously published literature. However, some tunnels were buried in soils, and test data showed that the strength envelopes of the soils followed power-law failure criterion. In this work, deep buried highway tunnel with large section was taken as objective, and the basic expressions of collapse shape and region were deduced for the highway tunnels in soils, based on kinematical approach and power-law failure criterion. In order to see the effectiveness of the proposed expressions, the solutions presented in this work agree well with previous results if the nonlinear failure criterion is reduced to a linear Mohr-Coulomb failure criterion. The present results are compared with practical projects and tunnel design code. The numerical results show that the height and width of tunnel collapse are greatly affected by the nonlinear criterion for the tunnel in soil.

Key words:upper bound theorem; tunnel collapse; highway tunnel; nonlinear failure criterion