掘进巷道爆破后排烟时间计算

Calculation of fume-drainage time of tunnel after blasting

摘要:

为研究掘进面爆破后排烟时间，推导掘进面炮烟运移规律公式，对排烟时间影响因素进行灰色关联度计算，得出主要影响因素的敏感性大小排序为：巷道出口到掘进面迎头的距离(0.827)＞风筒口到掘进面迎头的距离(0.738)＞风筒供风量(0.628)＞炮烟中CO初始体积分数(0.547).在归来庄金矿掘进巷道中进行炮烟监测试验，研究了压入式通风条件下，风筒口到掘进面迎头的距离L_O分别为10、15、20、25、30 m时，巷道出口到掘进面迎头的距离L_P分别为40、60、80、100、120 m的排烟时间.研究结果表明：排烟时间随巷道出口到掘进面迎头的距离增加而变长，两者拟合成线性关系；排烟时间随风筒口到掘进面迎头的距离增加而变长，成非线性增加；排烟系数c与L_O拟合成线性关系，并推导出不同工况下排烟时间的计算式；在试验及相似巷道的5个工况下进行验证，相对误差为6.1%，3.8%，5.4%、8.8%，9.3%，具有较好的准确性和可靠性

Abstract:

To research fume-drainage time of tunnel after blasting, the formula of removal law of blasting fume in tunnel is deduced. Through calculating the grey correlation degree of influential factors of fume-drainage time, the ranking results of sensitive degree of main influential factors are: distance of entrance to tunnel face (0.827) > distance of duct to tunnel face(0.738) > air flow in duct(0.628) > initial volumetric concentration of CO in blasting fume(0.547). Blasting fume monitoring tests were conducted in tunnel to study the fume-drainage time when the distance of duct to tunnel face L_O are respectively 10, 15, 20, 25, 30 m and the distance of entrance to tunnel face L_P are respectively 40, 60, 80, 100, 120 m under the condition of forced ventilation. Research findings reveal that: fume-drainage time increases with the longer distance of entrance to tunnel face. The fitting result of the both is linear relation; fume-drainage time shows nonlinear rise with the addition of the distance of duct to tunnel face. The fitting result of fume-drainage coefficient c and L_O is linear relation, and calculation formulas of fume-drainage time in different working condition are concluded. Verification of equation is carried out in 5 tested similar tunnels. And relative errors are respectively 6.1%, 3.8%, 5.4%, 8.8%, 9.3%, which have remarkable accuracy and reliability