Design Parameters of Roof Support Systems for Pre-Driven Longwall Recovery Rooms

摘要

Reduction in the recovery time required and improvements in safety during a longwall face move have compelled coal mine operators to examine and use predriven longwall recovery rooms. The recovery entry is developed at the longwall stop position and supported ahead of time so that the required combinations of standing and internal supports can be installed before the longwall face approaches. A calibrated three-dimensional finite element model, developed in conjunction with an underground test area, provided the critical components and design principals for a comprehensive parametric study. The study indicates that vertical, horizontal, and shear stresses concentrated on the outby abutment pillar corner of the recovery room resulting in deformations in the immediate roof above the primary roof support anchorage level.