Grouting method for dealing with tunnel collapse

Abstract

The invention relates to a grouting method for dealing with tunnel collapse which comprises the following steps: (1) directly sending two grouting pipes from an opening of a collapsed section into a collapsed slag body, controlling the grouting point to be 5 to 6 meters above the top of the opening, injecting the slurry into the loose body. During the grouting process, the slurry is lowered and wrapped by the grouting point, and the lower loose body is consolidated. As the slurry is solidified in the lower part and the liquid level of the slurry in the slag body is gradually raised to the pulping point, completing the wrapping and the consolidation of the loose body below the pulping point; (2) using the traditional soil arching effect principle to consolidate the loose body of the top arch of the collapsed section, that is, after the consolidation of the loose body in the range of 5 to 6 meters above the top of the opening, excavating the top of the tunnel of the collapsed section into an arch shape, and bearing the load of the upper loose body by using the arch effect; (3) after completing the loose ring reinforcement of 5 to 6 meters at the top of the opening, according to the supporting method of the V-type surrounding rock, the steel support made of the I-shaped steel and the top arch excavation work surface are firmly fixed every 0.5 meter, jointly bearing the load of thetop arch. The aim of the grouting method is to overcome the defects existing in the prior three traditional grouting methods and to provide a fast, efficient and safe method for grouting tunnel collapse.

Description

technical field [0001] The invention relates to the field of tunnel engineering, in particular to a method for treating tunnel collapse by using grouting. Background technique [0002] After the existing tunnel landslides accumulate loose bodies on the operation face, most of the loose bodies are reinforced by grouting, and anchoring methods are adopted, such as grouting and anchoring method, large pipe shed grouting advance support method and collapse Pit grouting method. [0003] Most of the grouting anchoring methods are completed by hollow self-advancing anchor rods, using the drill bit that comes with the hollow self-advancing anchor rods to drill holes, and embedding them in the landslide body as the next grouting pipe. Control it between 15-30 degrees, and then use shotcrete to seal the tunnel face, then use medium and high pressure grouting method for grouting; during the process of drilling the hollow anchor rod into the landslide body, if there is a If there is a...

AI Technical Summary

Problems solved by technology

[0004] In the advance support method of large pipe shed grouting support, the pipe shed drilling rig is used to first drive the steel flower pipes with a diameter of Φ108~Φ189 into the landslide body along the top of the tunnel, and the drilling angle is controlled at 5-10 degrees, and then through the pipe shed on the pipe shed Hole grouting, if necessary, supplemented by a small pipe to adopt a larger external insertion angle to further increase the grouting range of the upper part of the pipe shed grouting; when using a large pipe shed grouting advance support, the lock must be made before the collapse section to prevent landslides Section expansion, the distance between the pipe shed is generally 20cm, and it is arranged along the tunnel arch at 120-180 degrees. The top of the tunnel is expanded to facilitate the arrangement of the pipe-shelf drilling rig for construction, but there is still a danger of expanding the collapsed tunnel section due to the expansion of the cavern adjacent to the collapsed section

[0005] For the above two methods, regardless of whether it is grouting anchorage or large pipe shed grouting, if the anchor rod or pipe shed is driven into the loose body, there may be multiple occurrences of pipe jamming or failure of normal construction.

[0006] The collapse pit grouting method directly injects grout into the landslide body at the surface collapse pit. The grouting range is enlarged and the cost is high. For example, if the distance between the surface collapse pit and the top of the tunnel is large, it is difficult for the grouting slurry to seep down to the top of the cave, for example, the grout cannot reach At the top of the tunnel, it cannot form a consolidation ring near the top of the cave. When cleaning the slag, a large amount of loose slag will slide down. Difficulty, and the controllability of crossing landslides cannot be guaranteed