软岩巷道地压与支护

Rock Stress Around Roadway in Soft strata and Roadway Support

介绍长广矿区浅部、深部软岩矿压显现特征和试验各种支护形式,以锚喷和U型钢可缩性支护为合适.

It is difficult to support roadways in Changguang coal field because of mining depth of 920m; soft surrouding rock; large strata stress; value of roadway deformation of more than 500mm and duration of deformation of 18 months; strata temperature of 41℃. The experience of supporting can be summed up in three items. they are: (1) rigid strong supports combined with bolting, shotcreting, steel arch ribs and 0.6-0.8m annular reinforded concret, compression strength 30 Mpa, are destructible and not available. (2) supports combined with bolting, shotcreting and mesh are suitable for supporting roadways in soft strata and make openings safe. The deformation of supports are large so that the supports adapt themself to circumstances. First, roadway is supported by bolting and shotcreting. wait till deformetion is stable, then roadway is supported again. fully resin anchored roof bolts checkred with long bolts and short bolts bear the most of rock weight. (3) U-steel yieldable support is the best of all kinds of supports. Supports tested include annular five-section 25 U-steel yieldable support, four-section 25 U-steel yieldable support with two inclined legs and five-section 29 U-steel inverted arch yieldable support. They basically are able to control deformation of surrounding rocks and heave floor, reduce rock stress, adjust stress of surrounding rock and improve support bearing condition.