Composite liner structure of four-track large-span wall-foundation arched tunnel

Abstract

The invention relates to a composite liner structure of a four-track large-span wall-foundation arched tunnel. According to the composite liner structure provided by the invention, subsidence of an arch crown of a four-track large-span tunnel can be effectively controlled, and crack of a liner, even a tunnel collapse accident caused by subsidence of an arch springing and deformation of the arch crown can be avoided so that the stability and the safety of tunnel construction and operation are ensured. The composite liner structure comprises a forepoling structure, a preliminary poling structure and a secondary liner structure which are arranged from inside to outside. The secondary liner structure comprises a secondary liner structure (31) at an arch part, wall-foundation structures (32) at two sides of a tunnel and an inverted arch; the forepoling structure comprises a forepoling structure (11) at the arch part and forepoling structures (12) on the side walls of a wall foundation; the preliminary poling structure comprises preliminary poling structures (21) at the arch part and preliminary poling structures (22) on the side walls of the wall foundation; and the lower ends of the preliminary poling structures (21) at the arch part and the secondary liner structure (31) at the arch part are respectively supported at the upper ends of the wall-foundation structures (32) at two sides of the tunnel.

Description

technical field [0001] The invention relates to a lining structure of a railway tunnel, in particular to a lining structure of a four-line long-span tunnel in a shallow buried section of a soft rock formation. Background technique [0002] my country is a mountainous country, especially in the southwestern mountainous area, where the terrain and geological conditions are extremely complex, and the proportion of bridges and tunnels is large. In most railway lines under construction and proposed, the proportion of tunnels accounts for more than 50% of the total length of the lines, and the proportion of tunnels in some sections It is more than 90%. Due to the limitations of terrain and transport capacity, a large number of station layouts need to extend into the tunnel. In recent years, with the development of road network construction to mountainous areas, the pre-design work of high-standard railways represented by Shanghai-Kunming Passenger Railway, Yungui, and Chenglan in S...

AI Technical Summary

Problems solved by technology

[0003] In the process of tunnel construction, the shallow buried section of the tunnel entrance has always been a difficult point in construction. For the four-line long-span tunnel, due to the large span, shallow buried depth, and heavy surrounding rock load, and most of the mountain surface rocks in the shallow buried section of the entrance are extremely weathered, the strength Low, poor stability, using traditional support structures and excavation methods, after excavation, the arch foot sinks heavily, and the deformation of the vault is not suitable for control, which may even lead to cracking and instability of the lining, resulting in collapse accidents

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