房式开采煤柱回收时老顶来压步距研究

Study of Main Roof Weighting Pace During the Process of Pillar Extraction in Chamber Mining

以兰兴煤矿即将布置的回收旧房式开采所遗留的煤柱2201工作面为原型建立数值计算模型,经模拟计算得出,老顶的初次来压步距为30 m,周期来压步距为12 m,周期来压步距约为初次来压步距的1/2。老顶初次来压时的断裂位置位于旧采空区靠近煤柱一侧的上方,这与正常回采时老顶初次来压时两端破坏处位于老顶两侧靠近支座处的上端不同。

Based on the 2201 coal pillar working face which was left during the recovery of old type mining of Lanxing mine, by this analog calculation, the initial weighting pace is 30 m, and the periodical weighting pace is 12 m, the initial weighting pace is twice the length of the periodical weighting. The breaking position of the initial weighting pace of main roof is located over the old mine goaf near one side of the coal pillar,which is different from the location of the initial weighting of main roof in the normal backstopping, which is over the main roof near the support.