A construction method of water-rich loess tunnel passing through loess rush valley

Abstract

The invention discloses a construction method for a water-rich loess tunnel passing through a loess flushing valley. The constructed loess tunnel includes a tunnel entrance section, a flushing valley shallow-buried tunnel section and a front tunnel section. The flushing valley shallow-buried tunnel section is connected to the tunnel entrance Between the entrance section and the front tunnel section; during the construction of the loess tunnel to be constructed, the steps include: 1. construction of the entrance section of the tunnel; 2. construction of the tunnel section buried shallowly in the valley; The method of the invention has the advantages of simple steps, reasonable design, convenient construction, and good application effect. According to the different formations of the tunnel entrance section, the shallow-buried tunnel section and the front tunnel section, a reasonable advanced reinforcement method and a tunnel base reinforcement method are selected for the tunnel. The soil reinforcement can effectively ensure the safety and reliability of the excavation process of the rich water large-section loess tunnel, and can effectively improve the stability of the excavated and formed tunnel hole.

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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