Surface Subsidence Prediction by Nonlinear Finite‐Element Analysis

Abstract

An improved two‐dimensional plane‐strain numerical procedure based on the incremental‐iterative nonlinear finite‐element method is developed to predict ground subsidence caused by underground mining. The procedure emphasizes the use of the following features: (1) An appropriate constitutive model that can accurately describe the nonlinear behavior of geological strata; and (2) an accurate algorithm for simulation of excavation sequences consistent with the actual underground mining process. The computer code is used to analyze a collapse that occurred in the Blue Goose Lease #1 Mine in northeastern Oklahoma. A parametric study is conducted to investigate the effects of some selected factors on the shape and extent of subsidence profiles. Analyses of the numerical results indicate that the nonlinear finite‐element technique can be employed to meaningfully predict and characterize the potential for ground subsidence due to underground mining.