在构造应力场中采动对底板运输巷道稳定性的影响

MINING-INDUCED INFLUENCES ON STABILITY OF FLOOR HAULAGE ROADWAY IN TECTONIC STRESS FIELD

利用有限元软件,建立了底板运输巷道锚喷支护稳定性分析的三维计算模型,分析了在范各庄煤矿构造应力场条件下不同工作面回采顺序对底板运输巷道稳定性的影响。提出在构造应力场中,开采运输巷道上方的煤体使巷道产生拉伸形变是巷道破坏的主要根源。指出在保留上方煤柱使运输巷道处于近似双向等压条件下,以减轻或避免回采引起的支撑压力的强烈影响,为在高水平应力场条件下底板运输巷布置的重要原则。经开滦范各庄工程实践检验,输运巷道使用期间减少了维护量,并保持了巷道稳定。

A three-dimensional computational model is applied to analyze the stability of rock-bolting and shotcreting support in the floor haulage roadway. The mining sequence effects in different working faces on stability of floor haulage roadway in high tectonic stress field in Fangezhuang Coal Mine are discussed. The main factor causing destruction of roadway in tectonic stress field is found to be the high tensile strain, which appears after the coal seam above haulage roadway is mined. In addition, the key principle of laying floor haulage roadway in high-level stress field is proposed in this paper to keep pillars above the haulage roadway unmined. In this way, the obvious influences of high abutment pressure induced by coal mining can be alleviated or avoided for the roadway is at nearly equal pressure on both directions. It is proved by engineering practices in Fangezhuang Coal Mine of Kailuan Group Limited Liability Company that the key principle is capable of reducing maintenance of haulage roadway in service and maintaining the stability of the roadway.