Concrete Pouring Method of Partition Wall Vault in Multi-Arch Tunnel

Abstract

A method for pouring concrete into a mid-board arch crown of a multi-arch tunnel is characterized by including the following steps of manufacturing and arranging a steel formwork, distributing concrete pump pipes, pouring concrete into the lower middle portion and concrete into the upper middle portion and pouring concrete into the arch part in a pressurizing mode. The method for pouring concrete into the mid-board arch crown of the multi-arch tunnel has the advantages that concrete poured into the arch crown is made to be compact at a time, working efficiency and engineering construction quality are improved, and engineering cost is reduced.

Description

technical field [0001] The invention relates to a concrete pouring method, in particular to a concrete pouring method for a partition wall vault in a multi-arch tunnel. Background technique [0002] my country is a mountainous country, about 75% of the land is mountainous or heavy hills. In the past ten years, the road network traffic has gradually crossed the mountains and mountains, and the road tunnels in the mountains have grown at an average annual rate of 350 kilometers. Generally speaking, the construction of road tunnels has entered a period of rapid development. [0003] Early road tunnels generally adopted the structure type of double-hole separation. However, due to various conditions, the distance between the left and right lines of the double-hole tunnel cannot meet the construction requirements in many cases, so the multi-arch tunnel structure type appears. For multi-arch tunnels, the wall type has changed from the initial integral straight center wall to san...

AI Technical Summary

Problems solved by technology

[0004] At present, the construction of the partition wall mainly adopts one-time concrete pouring from the window openings of the steel formwork on both sides, and then welds the pump pipe on the middle top of the steel formwork to connect and pour the middle and upper concrete. This method requires a lot of rearrangement of the pump pipes and takes a long time. Pipe plugging is prone to occur, and the concrete in the middle and upper parts cannot be vibrated, resulting in insufficient concrete density and reduced concrete strength. When pouring vault concrete, it can only be properly pressurized when the concrete reaches the top of the formwork, and the vault concrete can only be filled by pressing It is impossible for the concrete to rise under the condition of resisting its own weight and cohesive force, and the air in the surrounding concrete closed vault cannot be discharged, and finally form air bubbles to resist the increased pressure of the pump pipe, and finally form uneven permanent voids in the vault

At present, the way to deal with the uncompacted vault is to pre-embed the pipe for later grouting. The pre-embedded pipe may not be able to reach the actual cavity position smoothly. Even if it reaches the cavity position, the pipe may be closed due to the backflow of concrete grout during pouring concrete, and finally the grouting cannot be done. Reasonable filling of the vault will result in the existence of permanent voids, which will bring safety hazards to the later use of the tunnel

In this method, if the pipe is blocked during pipe replacement, cold seams will be generated. Once cold seams are formed in the partition wall, it is difficult to deal with cold seams. The construction team may ignore the cold seams, which will affect the quality of use.

[0005] Therefore there are above-mentioned inconveniences and problems in known partition wall vault concrete pouring method

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