A 3-D Semi-Analytical Method for Subsidence Prediction and Stress Analysis in Coal Mining

摘要

The Semi-Analytical method can be used to solve a variety of problems in geomechanics and civil engineering. When it comes to layered rock strata and rock masses, it is superior to all other analytical methods. This paper presents the application of a 3-D semi-analytical method to 3-D surface subsidence and stress analysis caused by mining. In this semi-analytical method the layered elements and triangular elements are used alternatively. Their displacement pattern, strain matrix, elastic matrix, stiffness matrix, load matrix and stress matrix are presented. A numerical simulation program based on the semi-analytical method has been developed using Fortran 90. This program is suitable for subsidence prediction and stress analysis of room and pillar mining, strip longwall and mechanized longwall mining methods. It is applicable to all geological conditions and mining methods. Comparing with the finite method, this method reduces significantly the number of simultaneous equations to be solved and the amount of data preparation. It not only reduces the computer memory, but also runs faster and cost less.