中厚煤层用混凝土垛沿空留巷

Supports for road-side and for gateway left along the goaf

一、31114工作面概况 31114工作面为-600后组西区11煤层工作面。11煤层赋存稳定,厚度1.9～2.04m,煤层倾角16°～18°,顶板为砂质页岩,厚约8～10m,易冒落,底板为泥质细砂岩,厚度2.0m左右。31114工作面在F3断层以西采用单巷布置,采后留巷。

two papers in this issue, namely, 'Experience with using concrete cribs for supporting a gateway left along the goaf in a medium-thick coal, seam' and 'Experience with leaving a gateway along goaf in a thin seam', describe experience with roadside support, and supports in a gafeway leaving along the goaf in Xinwen Mining Administration, Shandong Province and in Linxi, Kailuan Mining Administration. Rockbolting with wire-mesh was employed to support a gateway in about 2m thick seam in Suncun Mine, Xinwen Mining Administration. After coal extraction, concrete slab cribs were used to maintain the gateway leaving along the goaf. Its cost reduced by about 200 Yuan per meter of gateway as compared with wooden chocks during the whole service life of the gateway. In Linxi mine, Kailuan Mining Administration, the immediate roof is thick. It collapses with the advance of coal face, and can fill the goaf with fallen rocks. No significant periodic weighting of the nether roof and floor heaving was observed. Under such conditions, 25 U yieldable arches strengthened by middle wooden props with wire mesh against waste flushing were used. At a dip angle of 12-22 deg, no road-side support was necessary. The advance rate and the heading efficiency were higher than those in gareway driven along the goaf and in gateway with coal pillars.