Reverse tunnel entering construction method for tunnel special-shaped protection arch on slope accumulation body

Abstract

The invention relates to a reverse tunnel entering construction method for a tunnel special-shaped protection arch on a slope accumulation body. The reverse tunnel entering construction method comprises the steps that the protection arch is divided into a front section and a rear section to be constructed in sequence, an upper section is constructed firstly for each section and then a lower section is constructed for each section; sectional and batched excavation and sectional and batched bottom falling are adopted for tunnel entering excavation, the single excavation amount is reduced as muchas possible, it is guaranteed that tunnel entering excavation is carried out under supporting of the protection arch and an advanced long pipe shed, and construction safety is guaranteed; and the structure of the protection arch is in a special shape, the heights of arch feet on the two sides are different, specifically, it is guaranteed that the arch feet fall on bedrock according to the elevation of the bedrock on site, the excavation amount is greatly reduced, construction disturbance to the slope accumulation body is reduced, the project amount of side slope and upward slope protection issaved, the construction cost can be reduced, and the construction period is shortened.

Description

technical field [0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a reverse construction method for a special-shaped protective arch of a tunnel on a slope deposit. Background technique [0002] Tunnel construction is one of the key processes in tunnel construction, and its success directly affects the construction period of the entire tunnel project and the structural safety of the tunnel entrance. Conventional tunnels generally adopt the support measures of 2m long sleeve arch and advanced long pipe shed, and excavate into the hole according to the step method or the reserved core soil method. [0003] However, when the tunnel entrance section is located in unfavorable geology such as loose deposits and slope deposits, and is under unfavorable terrain conditions such as shallow burial, obvious bias pressure, steep mountains, and high upward slopes, if the conventional tunnel entry method is adopted, the mountain at the...

AI Technical Summary

Problems solved by technology

[0003] However, when the tunnel entrance section is located in unfavorable geology such as loose deposits and slope deposits, and is under unfavorable terrain conditions such as shallow burial, obvious bias pressure, steep mountains, and high upward slopes, if the conventional tunnel entry method is adopted, the mountain at the entrance of the tunnel will be It is very prone to collapse when it encounters water or construction disturbance, and there is a major safety risk

Images