Construction method of water-rich loess tunnel capable of passing through loess gulley

Abstract

The invention discloses a construction method of a water-rich loess tunnel capable of passing through a loess gulley. The water-rich loess tunnel comprises a tunnel entrance entering section, a gulleyshallow-buried tunnel section and a front side tunnel section, wherein the gulley shallow-buried tunnel section is connected between the tunnel entrance entering section and the front side tunnel section; the construction method comprises the following steps: 1, constructing the tunnel entrance entering section; 2, constructing the gulley shallow-buried tunnel section; and 3, constructing the front side tunnel section. The construction method is simple in step, reasonable in design, simple and convenient in construction and excellent in using effect; the reasonable look-ahead reinforcing method and the tunnel base reinforcing method are selected to reinforce the tunnel soil mass according to different stratums of the tunnel entrance entering section, the gulley shallow-buried tunnel section and the front side tunnel section, the excavation process of the water-rich large-cross-section loess tunnel can be effectively ensured to be safe and reliable, and the stability of the dug formedtunnel can be effectively improved.

Description

technical field [0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a construction method for a water-rich loess tunnel passing through a loess flush valley. Background technique [0002] The valley is a trough-shaped depression formed by the erosion of the storm. The small one is only more than ten meters long, and the large one can reach tens of kilometers. Bursts are mostly formed by the collection of sheet flows on slopes, because the surface on slopes is not flat, so there are local low and flat depressions. In the depression, the flowing water particles on both sides and upstream of it converge to the lowest point in the middle to form a flow center line. When the water layer thickens, the flow velocity increases, and the scour capacity increases, the depression is gradually scoured and deepened to form a valley. and ravine water. According to the size and development shape of the valley, it can be divided into fou...

AI Technical Summary

Problems solved by technology

In particular, shallow buried tunnels and shallow tunnel sections have high permeability coefficient and high water content, and the water content of the surrounding rock is significantly affected by atmospheric precipitation. Great risk to the tunnel

[0006] In addition, due to the special mechanical properties and structural characteristics of loess, the poor stability and low bearing capacity of surrounding rock have become the main problems faced by loess tunnel construction

Loess tunnels during the operation period, especially heavy-duty railway tunnels, are prone to settlement and deformation of the base under the long-term train vibration load, which will lead to deterioration of driving conditions and endanger driving safety in severe cases

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