Fault processing method of high pressure water enrichment area

Abstract

The invention relates to a fault processing method of a high pressure water enrichment area, comprising the following steps of: a. ascertaining the boundary of a tunnel passing through a fault through geological exploration and advance geological prediction, and judging the inflow direction of the fault; b. excavating a drainage hole at the inflow side of the fault next to the tunnel according to the inflow direction of the fault; c. carrying out advanced grouting pre-strengthening per cycle on a tunnel working face under the condition that the drainage hole drains and depressurizes; d. drilling towards the tunnel direction in the drainage hole before excavation and after the grouting pre-strengthening per cycle of the tunnel meets requirements, increasing the drainage ability by using the drilled hole, and further reducing the seepage water pressure in a surrounding rock at the periphery of the tunnel; and e. tunneling from the tunnel working face. Through arranging the drainage hole, the invention reduces the seepage water pressure near the tunnel, effectively avoids the occurrence of the phenomenon of water burst, mud gushing (stones) of fault broken rocks under the action of high pressure water in the construction process and improves the safety and the reliability of tunnel construction and operation.

Description

technical field [0001] The invention relates to a processing method for a tunnel crossing a fault in a high-pressure water-rich area, belonging to the field of tunnels and underground engineering. Background technique [0002] With the rapid development of my country's transportation construction, tunnel projects may often encounter faults in high-pressure water-rich areas. The faults in high-pressure water-rich areas are generally large in scale, and the rock mass in the faults is broken. Coupled with the influence of high-pressure and water-rich areas, it is very easy to occur during tunnel construction. Large-scale water inrush, mud (stone) inrush phenomenon, resulting in casualties, seriously affecting the safety of tunnel construction and operation. [0003] At present, in accordance with the principle of "blocking-based" for tunnels passing through faults in high-pressure water-rich areas, the advanced full-section grouting method is used to reinforce the fault fracture...

AI Technical Summary

Problems solved by technology

[0004] The existing technology completely relies on the grouting reinforcement ring to resist the strong water and soil pressure during the tunnel excavation construction. On the one hand, the grouting reinforcement range is large, generally 1 to 2 times the tunnel diameter, and the number of grouting holes is large. Under these conditions, the grouting process is complicated and the construction time is long; on the other hand, because the grouting reinforcement effect is greatly affected by the heterogeneity of the stratum, material selection and technical level, it is easy to have grouting blind spots in the process of project implementation, and high-pressure water-rich faults Under the action of high water pressure, the broken rock mass in the tunnel can easily break through the grouting blind area, resulting in water inrush and mud (rock) inrush. The tunnel construction has great potential safety hazards, which is not conducive to the safe construction of the tunnel.

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