Stability Analysis of Water-Resistant Strata in Karst Tunnel Based on Releasable Elastic Strain Energy

Abstract EN

In this paper, the energy instability criterion of water-resistant strata and rock mass failure index (RMFI) are proposed, respectively, based on releasable elastic strain energy Ue.

RMFI is employed to represent the damage extent of water-resistant strata.

When RMFI<1.0, rock mass is stable.

When RMFI=1.0, rock mass is in the critical instability state.

When RMFI>1.0, rock mass is unstable.

The releasable elastic strain energy Ue and RMFI program is performed by FISH programming language of Flac3D software.

Then, the authors apply Flac3D software to analyze the distribution law of releasable elastic strain energy Ue and failure zone under different width of concealed karst cave.

Finally, combined with the numerical analysis, a case study is carried out to illustrate the rationality, effectiveness, and feasibility through using RMFI to predict safe thickness of water-resistant strata.