条带煤柱膏体充填开采覆岩结构模型及运动规律

Structure model and movement law of overburden during strip pillar mining backfill with cream-body

以岱庄煤矿2351膏体充填工作面为例,研究了条带煤柱膏体充填开采覆岩时空结构模型及运动规律。结果表明:随着工作面的推进,覆岩由"C"型空间结构逐渐转化成不等高支撑的铰接岩梁;工作面的直接顶板即为基本顶,初次来压步距33.6 m,前4次周期来压步距分别为18.3、8.8、13.7、9.0 m;覆岩重力主要作用在工作面前方煤壁和充填膏体上,顶板超前应力和影响范围较小,主要影响范围小于15 m;2351工作面在现行工艺技术条件下,最大合理控顶距为8.8 m,充填支架合理工作阻力为27 MPa、合理初撑力为21 MPa。

Space-time structure model and movement law of overburden were researched during strip pillar mining backfill with cream-body,taking 2351 backfilling face for an example.The results show that 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 33.6 m,and the periodic weighting length respectively are 18.3,8.8,13.7 and 9.0 m 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 is less than 15 m.In current technology conditions of face 2351,the reasonably maximal roof control distance is 8.8 m,the reasonable working resistance of support backfilling is 27 MPa,and the support setting load is 21 MPa.