Device for improving bearing performance of steel arch of dilative soil large-section tunnel

Abstract

The invention discloses a device for improving the bearing performance of a steel arch of a dilative soil large-section tunnel. The device comprises an arched support. High-strength round spiral steel bars and rigid supporting bases are arranged at large arch feet at the bottom of the arched support, each large arch foot comprises an upper-layer steel plate and a lower-layer steel plate connected with the upper-layer steel plate through five high-strength round spiral steel bars in a plum pile mode, and the rigid supporting bases penetrate through the high-strength spiral steel bars; five supporting base insertion grooves are formed in each lower-layer steel plate, and the supporting base insertion grooves are used for fixing the supporting bases so as to guarantee the overall stability of the steel arch. The device can relieve the settlement deformation of surrounding rock at the initial stage of excavation of the dilative soil tunnel, improve the self-stabilization capacity of the tunnel effectively and lastingly, form a multifunctional surrounding rock reinforcement area and guarantee the safety of tunnel constructors and protect equipment.

Description

Technical field [0001] The patent of the present invention relates to the technical field of geotechnical engineering, in particular to a device for improving the load-bearing performance of the steel arch frame of a large-section tunnel with expansion and contraction soil. Background technique [0002] In swelling and shrinking soil areas, when large-section tunnels such as railways and highways are constructed, the swelling and shrinking soils themselves have the characteristics of water-absorbing expansion and water-loss shrinkage, which can easily cause the tunnel surface to crack and the surrounding rock deformation, causing collapse, Geological disasters such as mud gushing occur, which endanger the lives of construction workers and damage production equipment. According to the monitoring results of the surrounding rock deformation of multiple railway and highway tunnels with large cross-sections, it can be seen that the deformation of the surrounding rock of the swelling a...

AI Technical Summary

Problems solved by technology

[0004] 1. Adopt large arch foot structure: Although the support structure of large arch foot can reduce the earth pressure on the tunnel face, reduce the vault and surface settlement, and improve the self-stabilization ability of the surrounding rock, but for the expansive soil itself Due to the characteristics of water absorption expansion and water loss contraction, the large arch foot structure cannot satisfy the free change with the deformation of the surrounding rock, resulting in uneven settlement deformation of the tunnel support structure

[0005] 2. Adopt flexible support structure: Although the deformability of the tunnel support structure can be realized, its reinforcement range is relatively small, and the action time is short, the ability to improve the self-stabilization of the tunnel surrounding rock is limited, and the effect of controlling the surface settlement is general. The reinforcement range cannot be effectively formed, thereby reducing reliability

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