In order to characterize the behavior of a main gate during retreating of longwall faces and to evaluate the performances of five different support types, 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 convergence model, represented by an exponential function, was developed on the basis of statistical analyses. In addition to the convergence model, convergence velocity and convergence acceleration models were also derived and interpreted in terms of gate road behavior. It was determined that the convergence depends on the loading region, the time, the location of the upper and lower longwall faces, the support type and pattern, and the static and dynamic support loads. Convergence velocity and acceleration curves provide better means to interpret the performance of supports and gate roadway behavior.
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