Method for constructing from inclined shaft to main tunnel in weak surrounding rock

Abstract

The invention discloses a method for constructing from an inclined shaft to a main tunnel in weak surrounding rock, which is performed according to the following construction steps: 1) climbing at a gradient of 20 to 25 percent and expanding and excavating the inclined shaft at a position 8 to 12 meters away from a construction edge of the main tunnel, and expanding and excavating a curved roadway at a position 1 to 3m higher than a contour line of a main tunnel cross section wherein the climbing height from a starting point to an ending point is 1 to 3m; 2) installing a large arch supporting frame on the main tunnel cross section, cutting off side wall supporting legs of a small arch supporting frame, and overlapping the two supporting legs of the small arch supporting frame on the large arch supporting frame; 3) inserting a plurality of advanced small pipes into a rock strata transversely along the top of the large arch supporting frame and vertically excavating to three steps of preserved core soil of the main tunnel; and 4) excavating an upward arch at the bottom of the main tunnel because the other side of an intersection of the inclined shaft and the main tunnel is an end wall. The method solves the problem of difficult construction from the inclined shaft to the main tunnel in the weak surrounding rock or sites with complex geological condition changes, greatly reduces safety risks, and has obvious effects.

Description

technical field [0001] The invention relates to the field of excavating tunnels in mountains, in particular to a construction method for turning inclined shafts into normal tunnels in weak surrounding rocks. Background technique [0002] The main tunnel of the tunnel is designed as a single-hole double-track tunnel, and two inclined shafts are set up for construction. Among them, the surrounding rock at the intersection of the Tubozi inclined shaft and the main tunnel is Tertiary sandstone interbedded with thin mudstone, and the sandstone is layered and horizontally bedding. A small amount of water seepage, poor diagenesis, extremely soft surrounding rock, suitable for deformation and collapse. For this kind of surrounding rock, if the conventional "small pilot tunnel expansion" method is adopted, the safety risk is extremely high, and the cost is high and the progress is slow. [0003] With the rapid development of railway construction, there are more and more long tunnels...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a construction method for turning an inclined shaft into a normal tunnel in weak surrounding rocks, which solves the construction problem of turning an inclined shaft into a normalizing tunnel in areas with weak surrounding rocks or complex geological conditions, greatly reduces safety risks, and has remarkable effects

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