A step-by-step grouting reinforcement method for extremely broken surrounding rock in underground engineering

Abstract

The invention discloses a step-by-step grouting reinforcement method for extremely broken surrounding rocks in underground engineering, which comprises the following steps: S1, grouting reinforcement for shallow extremely broken surrounding rocks; Surrounding rocks are reinforced by grouting; S3. Perform a pull-out test on the grouted anchor cable in the middle to determine whether the pull-out force reaches the set range. If yes, execute step S4; if not, execute step S5; S4. The extremely broken surrounding rock in the deep part is reinforced by grouting; S5, adjusting the parameters of the grouting anchor cable support in the middle part. The invention can quickly and effectively reinforce the extremely broken surrounding rock in underground engineering; quickly condense the extremely broken surrounding rock in the shallow part into a whole, improve the integrity of the surrounding rock, and effectively solve the phenomenon of hole collapse and drill sticking in the surrounding rock; make the central part And deep extremely broken surrounding rock enhances its own bearing capacity, improves the initial support strength of surrounding rock, improves the mechanical properties of extremely broken surrounding rock and controls its deformation and failure.

Description

technical field [0001] The invention relates to the technical field of safety in underground engineering, in particular to a step-by-step grouting reinforcement method for extremely broken surrounding rock in underground engineering. Background technique [0002] With the continuous development and utilization of underground space, underground engineering is facing the problems of large in-situ stress and broken surrounding rock, especially when underground engineering passes through surrounding rock with complex geological conditions such as faults and old empty areas. The extremely broken surrounding rock has great influence on the stability of underground engineering. Sex poses a major hazard. [0003] At present, the commonly used reinforcement methods for extremely broken surrounding rocks are anchor rods (cables) and grouting reinforcement, which have the following defects: traditional grouting has long cement slurry solidification time, low early strength, easy segreg...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used reinforcement methods for extremely broken surrounding rocks are anchor rods (cables) and grouting reinforcement, which have the following defects: traditional grouting has long cement slurry solidification time, low early strength, easy segregation and precipitation of grout, and voids after injection and solidification Due to the poor integrity and stability of the extremely broken surrounding rock, the drill stuck phenomenon occurred when the anchor (cable) hole was drilled, and the extremely broken surrounding rock could not be effectively reinforced by the anchor (cable). Reinforcement; when anchor rods (cables) are used for support, because the cohesive force between the anchoring agent and the extremely broken surrounding rock is too small, the anchoring force cannot be guaranteed, and the mechanical properties of the anchor rod (cable) cannot be fully exerted; the cracks in the extremely broken surrounding rock Developed, conventional grouting is used for reinforcement. After the cement slurry is injected into the surrounding rock, it is easy to cause grout leakage, and it is impossible to effectively strengthen the extremely broken surrounding rock.

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