Intercepting method for gas gushing out during tunnel construction

Abstract

The invention discloses an intercepting method for gas gushing out during tunnel construction. The intercepting method comprises the following steps that A, advanced detection of the gas concentrationof a tunnel face is conducted; B, the situation that the advanced gas concentration of the tunnel face endangers normal driving of the tunnel face is determined; C, a plurality of exhaust guiding holes are formed in the positions, 5-40 m behind the tunnel face, of the two side walls of a tunnel correspondingly, each exhaust guiding hole extends into the part, ahead of the tunnel face, of a rock mass in the tunnel driving direction, all the end points of the exhaust guiding holes are arranged along the periphery of the tunnel, and all the start points of the exhaust guiding holes communicate with a suction device; and D, the suction device sucks the gas in the part, in the tunnel face area, of the rock mass under the negative pressure. By applying the intercepting method for the gas, the exhaust guiding holes are formed in the positions, behind the tunnel face, of the two side walls of the tunnel and extend into the parts, ahead of the tunnel face, of the rock mass, and all the end points of the exhaust guiding holes are arranged on the outline periphery of the to-be-driven tunnel in an enveloping mode so that protection of the upper portion, the lower portion, the left portion andthe right portion of the tunnel can be formed, suction is well conducted accordingly, and the situation that the gas gushes out abnormally, and a safety accident occurs consequently is prevented; andall the exhaust guiding holes for suction are not located in the tunnel face, so that normal driving of the tunnel face is not affected.

Description

technical field [0001] The invention relates to the field of tunnel construction, in particular to a method for intercepting gas gushing out from tunnel construction. Background technique [0002] Gas gushing out of the rock body is often encountered during tunnel excavation construction, which can easily cause safety accidents. Therefore, gas drainage in tunnel excavation is a very important task. The existing method is to detect excessive gas concentration in advance at the face of tunnel excavation When drainage is required, drain holes are made on the face of the face, and then the gas gushing out of the holes is sucked by the suction device to reduce the gas concentration in the face area so that the gas concentration does not affect the gas concentration of the face. For normal excavation, although this method can make the tunnel face safe excavation, it greatly reduces the excavation speed of the tunnel face and affects the construction period. Contents of the inven...

AI Technical Summary

Problems solved by technology

[0002] Gas gushing out of the rock body is often encountered during tunnel excavation construction, which can easily cause safety accidents. Therefore, gas drainage in tunnel excavation is a very important task. The existing method is to detect excessive gas concentration in advance at the face of tunnel excavation When drainage is required, drain holes are made on the face of the face, and then the gas gushing out of the holes is sucked by the suction device to reduce the gas concentration in the face area so that the gas concentration does not affect the gas concentration of the face. Normal excavation. Although this method can make the tunnel face safe excavation, it greatly reduces the excavation speed of the tunnel face and affects the construction period.

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