条带煤柱膏体充填开采覆岩结构模型及运动规律

Space-time structure model and movement law of overburden are researched during strip pillar mining backfill with cream-body, taking 2351 backfilling face for an example. The results show that as below. As the face advances, overburden strata are gradually transformed from the "C" type space structure into articulated rock beam with unequal height supports. The immediate roof of working face is the main roof; the first weighting interval is 33.6m, and the periodic weighting length respectively are 18.3m, 8.8m, 13.7m and 9m for the last four times.The overburden gravity mainly acted on coal wall in front of face and backfill paste, which had little effect on roof advance stress, and the influence scope was less than 15m. In current technology conditions of face 2351, the reasonably maximal roof control distance was 8.8m, the reasonable working resistance of support backfilling is 27Mpa, and the support setting load is 21Mpa.