The construction method of split self-propelled formwork trolley for the second lining vault of long-span subway tunnel

Abstract

The invention discloses a construction method for the second lining vault of a large-span subway tunnel using a split self-propelled formwork trolley. The construction adopts the three-step method of inverted arch first, side wall follow-up, and vault closure. Among them, inverted arch first: during the construction of the inverted arch, the I-beam next door in the bottom of the inverted arch construction section is partially removed, and then the inverted arch construction is carried out; Wall follow-up: when constructing the inner wall of the inverted arch range, partially remove the horizontal part of the partition in the construction section of the side wall; vault closure: construct the vault within the range of the side wall. The invention overcomes the structural deformation caused by the construction of the second lining of the high-risk large-span underground excavation tunnel under complex geological conditions, which causes risks such as surface subsidence and tunnel instability.

Description

technical field [0001] The invention relates to the field of tunnel construction. More specifically, the invention relates to a construction method for the second lining vault of a large-span subway tunnel using a split self-propelled formwork trolley. Background technique [0002] In urban rail transit, railways, highways, underground caverns and other underground engineering long-span tunnel constructions, for sections with poor surrounding rock grades and complex geological conditions, the double-side pilot pit method, The CRD method and other construction methods with temporary support structures such as temporary inverted arches and temporary partition walls are used for construction to control the deformation of the primary support structure. In traditional construction, before the construction of the secondary lining, it is necessary to carry out trial demolition of temporary supports one by one, and at the same time intensively observe the deformation of the primary...

AI Technical Summary

Problems solved by technology

The disadvantages of the existing conventional lining technology include: 1) The temporary support of the initial support structure is used as a whole, which is risky; 2) In order to prevent major hazards such as tunnel deformation caused by the removal of the temporary support, the distance of the construction section is limited, which cannot meet the requirements of the tunnel lining. The process flow operation is required, and the efficiency is low; the overall lining of the trolley is used, and the construction cost is high; 3) the overall support is broken, the workload is heavy, resulting in a poor construction environment in the tunnel; 4) the large section has a large arc, the arch wall is integrally lined, and steel The lashing operation is difficult and the efficiency is low; 5) Repeatedly building and dismantling the lining system takes a lot of time and the cycle is long; 6) High-altitude operations have high risks

Images