Modeling the behavior of longwall coal mine gate roadways subjected to dynamic loading

In order to characterize the behavior of a main gate during retreating of l ongwall faces and to evaluate the performances of five different support ty pes, including rock bolts and steel sets, a total of 21 convergence and 18 floor-heave stations were installed. Consequently, about 11,500 convergence and 7200 floor-heave data points were obtained over a period of 14 months. In order to simulate the behavior of a supported main gate roadway, a conv ergence model, represented by an exponential function, was developed on the basis of statistical analyses. In addition to the convergence model, conve rgence-velocity and convergence-acceleration models were also derived and i nterpreted in terms of gate road behavior. It was determined that the conve rgence depends on the loading region, the time, the location of the upper a nd lower longwall faces, the support type and pattern, and the static and d ynamic support loads. Convergence-velocity and acceleration curves provide better means to interpret the performance of supports and gate roadway beha vior. (C) 2001 Elsevier Science Ltd. All rights reserved.