Construction method for wind-blown sand tunnel

Abstract

The invention discloses a construction method for a wind-blown sand tunnel, belonging to the construction field of tunnels. The construction method for the wind-blown sand tunnel is realized by the following steps: 101: construction of upper steps; 102: construction of lower steps; 103: construction of inverted arch combining parts; 104: construction of secondary lining; and 105: ring closing of inverted arch. Aiming at the loose, soft and unstable geometrical conditions of sand layers, wind-blown sand layers and the like, the construction method for the wind-blown sand tunnel solves the problems of collapse due to frequent sand leakage, and deformation of supporting in the normal construction method; the inverted arch combining parts are constructed firstly, therefore, the bearing capability of the wall corner foundation of a primary supporting is enhanced, the side pressure transferred by soil bodies at two sides is inhibited effectively, simultaneously conditions are created for achieving the aim that the deformation of the primary supporting finally tends to be stable by quickly starting the construction of the secondary lining; the excavation is carried out according to the characteristics of the tunnel, such as long distance, ultra-shallow buried layer, large profile and granular bulk rocks, the technical difficult problems in the field are overcome, therefore, the construction method provides important guide significance for the construction of the tunnels of similar geometrical conditions.

Description

technical field [0001] The invention relates to a construction method of a tunnel, in particular to a construction method of an aeolian sand tunnel. Background technique [0002] As we all know, the geographical conditions of the aeolian sand stratum are harsh. In this stratum environment, the sand layer and the aeolian sand layer are loose, weak and unstable, especially the shallow hilly unit of the desert, which is a typical aeolian silt geology. The formation has a loose structure, single particles, small particle size, low cohesion, no plasticity, poor gradation, low compressibility, strong water permeability, relatively low shear strength, and no self-stabilizing force. It is already quite difficult to excavate ordinary tunnels in the geographical environment, and it is even more difficult to excavate large-span tunnels. [0003] The Shenmu No. 1 Tunnel in Shaanxi Province is located on the top of the mountain between Laolongchigou and Shuimo River, on the west side of...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for the aeolian sand stratum, in view of the loose, weak and unstable geological conditions such as sand layers and aeolian sand layers, where sand leaks often occur in conventional construction and cause collapse and support deformation. Convenience in construction, beneficial to control of settlement deformation, safety and controllability, the construction method of aeolian sand tunnel excavated by adopting the method of "constructing the junction of the inverted arch side wall first and reserving the core soil step method" for tunnel excavation

Images