Abstract:

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.

Key words: Tianping Tunnel, gas drainage and outburst prevention, meshshaped borehole drilling of coal, monitoring