A waterproof structure and construction method for bolt hole of shield tunnel segment

Abstract

The invention discloses a shield tunnel pipe piece bolt hole waterproof structure and a construction method. The shield tunnel pipe piece bolt hole waterproof structure comprises a bolt located in a bolt hole for connecting pipe pieces, a bolt gasket, a first waterproof gasket and a second waterproof gasket, wherein the bolt gasket is located between a bolt head of the bolt and the pipe pieces, the first waterproof gasket is located between the bolt gasket and the pipe pieces, and the second waterproof gasket is located between the bolt head and the bolt gasket. The plane, making contact with the pipe pieces, of the first waterproof gasket is a plane, and the plane, making contact with the bolt gasket, of the first waterproof gasket is provided with at least one ring of semicircular protrusion. The two end faces of the second waterproof gasket are both planes. According to the shield tunnel pipe piece bolt hole waterproof structure and the construction method, the waterproof pressure of the bolt hole can be increased, the pre-tightening force of the bolt can be adjusted according to needs, different waterproof pressure requirements can be met by changing the contact stress between the waterproof gaskets and the pipe pieces and the contact stress between the waterproof gaskets and the bolt gasket, and better durability is achieved.

Description

technical field [0001] The invention belongs to the technical field of tunnel waterproofing, and in particular relates to a waterproof structure and construction method for tunnel segment bolt holes by a shield method. Background technique [0002] The shield tunnel is a structure formed by the on-site assembly of multiple prefabricated segments. The segments are connected by bolts. In order to prevent groundwater from leaking into the tunnel from the joints of the segments, the joints near the outside of the segments are equipped with Water-proof sealing pads are provided with water-expandable rubber sealing rings at the bolt holes, and caulking is carried out on the inside. In projects with high waterproof requirements, a second waterproof sealing pad is installed near the inside of the joints. In actual engineering, due to the influence of factors such as the quality of prefabricated segments, the quality of construction and assembly, and the quality of gasket pasting, it...

AI Technical Summary

Problems solved by technology

Since the diameter of the bolt hole is generally about 6mm larger than the diameter of the bolt, the sealing ring will be extruded into the bolt hole after it expands with water. Since there is no lateral restraint, no expansion pressure can be formed, so the waterproof effect is very poor.

In addition, the water-swellable rubber material has poor stability under long-term immersion conditions, and the water-absorbing material is easily lost from the elastic body network of the rubber, which is manifested as a large mass loss and a decline in physical properties before and after long-term or repeated immersion in water

That is to say, the water-swellable rubber ring commonly used at present cannot generate swelling force when it swells with water, and cannot achieve the proper waterproof effect, and its stability and durability are insufficient.

Images