天坪铁路隧道瓦斯抽放防突技术

Study of Technologies for Gas Drainage and Outburst Prevention of Tianping Railway Tunnel

渝黔铁路天坪隧道横洞工区为瓦斯突出工区,施工中为防治瓦斯突出必须进行瓦斯抽放,分析瓦斯抽放已有经验,确定了采用穿层网格预抽煤层瓦斯施工技术;结合隧道大断面及天坪隧道煤层赋存条件,确定了该技术的瓦斯抽放参数,在材料设备选型、钻孔布设、封孔施工、管路连接和瓦斯抽放监测等关键环节严格把关,并对抽放效果进行了检验。总结采用该项技术在经济、技术和安全生产等方面所取得的主要成果,以期为该项技术在类似隧道施工中的推广应用提供参考。

Tianping tunnel on Chongqing-Guizhou Railway is a gas tunnel. As a result,gas drainage technology should be applied. The technology of mesh-shaped borehole drilling of coal layer is decided based on analyzing the gas drainage experience. The gas drainage parameters are decided based on studying the coal storage conditions. The material and equipment selection,layout of boreholes,borehole sealing,pipeline connection and gas drainage monitoring are strictly controlled; and the gas drainage effect is examined. Finally,the main achievements of the mentioned technologies are summarized in terms of economy,technology and safe construction.