Seismic Performance of Coal Mine Overburden Dump Slope Using Extended Finite-Element Method–Based Voronoi Tessellation Scheme

Abstract

Assessment of the seismic damage of coal mine overburden (OB) dump slopes gets compromised due to negligence of the consideration of heterogeneity in the shape and size of its particles. In this paper, in situ material parameters for an OB dump slope were evaluated through multichannel analysis of surface waves (MASW) investigations performed at the Jambad opencast coal mine of India. To realistically simulate the heterogeneity of the OB dump materials, Voronoi tessellation scheme coupled with extended finite-element method (XFEM) (using RS2 software) was employed. Behavior of a double-benched OB dump slope under earthquake excitations with a wide range of strong motion parameters (such as peak ground acceleration, predominant frequency, bracketed duration, and Arias intensity) was investigated through XFEM. The influence of strong motion parameters on the seismic behavior of a double-benched OB dump slope was reported in terms of transient (during the earthquake motion) and permanent deformation (after the earthquake motion) at various key points of the slope. Finally, the levels of damage experienced by the OB dump slope under earthquake ground motions were assessed qualitatively. The study would be advantageous for the mining industry in framing the safety guidelines for OB dump slopes in coal mine areas susceptible to earthquakes. The performance of a double-benched coal mine overburden (OB) dump slope under earthquake excitations with a wide range of strong ground motion parameters (such as peak ground acceleration, predominant frequency, bracketed duration, and Arias intensity) was investigated by employing Voronoi tessellation scheme coupled with extended finite-element method (XFEM). The influence of strong ground motion parameters on the seismic behavior of the double-benched OB dump slope was reported in terms of transient (during the earthquake motion) and permanent or residual deformation of the slope at various critical points. Further, the levels of damage experienced by the OB dump slope under earthquake ground motions were assessed qualitatively. This research work may provide guidance to practicing engineers for considering the heterogeneity of the OB dump slope while assessing its seismic performance. The study is going to be useful for the design of OB dump slopes for coal mines located in a seismically active region. If the site-specific earthquake parameters are available, the study may provide important aspects of seismic design of the OB dump slope.