Anti-leakage treatment method of portal ring beam of metro station

Abstract

The invention provides an anti-leakage treatment method of a portal ring beam of a metro station. The anti-leakage treatment method specifically comprises the following steps of, before the binding ofa steel bar of the portal ring beam, embedding a grouting steel pipe at a water leakage point of the portal ring beam, and mounting full-cross-section grouting pipes respectively at interfaces between the portal ring beam, an external structure and a shield pipe piece; enabling a grouting part of the embedded grouting steel pipe to partially stretch into a soil layer and to be partially placed ina pouring area for the portal ring beam; and after the binding of the steel bar of the portal ring beam and before the closing of a template, smearing water-swelling water-stop glue respectively on the interfaces where the full-cross-section grouting pipes are mounted, then integrally pouring the portal ring beam and a water receiving channel, after the portal ring beam and the water receiving channel meet a design strength requirement, simultaneously grouting by the embedded grouting steel pipe and the full-cross-section grouting pipes, and finally, constructing a water diversion ditch to communicate the water receiving channel with water drainage ditches on the two sides of a track. By using the anti-leakage treatment method, the defective workmanship that is inevitable in the pouring process of the portal ring beam is effectively made up; the phenomenon of the water leakage of the portal ring beam is effectively controlled; and the construction quality is guaranteed.

Description

technical field [0001] The invention relates to the field of shield tunnel construction, in particular to an anti-seepage treatment method for a door ring beam of a subway station. Background technique [0002] At present, the shield method has become the most commonly used construction method in subway construction. Shield tunnels inevitably pass through water-bearing strata, and water seepage is particularly common at the joints between segments and door ring beams and at segment joints. . The leaking water at the joints of the segments is usually treated by synchronous grouting and secondary grouting through the grouting holes reserved on the segments; the ring beam of the portal is usually made of ordinary concrete with an impermeability grade of P10, with large particle size, The fluidity is poor. Since only the pouring window is reserved at 12 o’clock during the pouring process of the portal ring beam, the concrete is not compacted well, especially the portal ring bea...

AI Technical Summary

Problems solved by technology

The leaking water at the joints of the segments is usually treated by synchronous grouting and secondary grouting through the grouting holes reserved on the segments; the ring beam of the portal is usually made of ordinary concrete with an impermeability grade of P10, with large particle size, The fluidity is poor. Since only the pouring window is reserved at 12 o’clock during the pouring process of the portal ring beam, the concrete is not compacted well, especially the portal ring beam is only relying on the self-weight of the concrete and the vibrating rod on the outside of the portal ring beam to vibrate the formwork during the pouring process. There are even cavities in the range from 11 o'clock to 1 o'clock on the top; at the same time, because the grouting pipe is not effectively protected, it is easy to be blocked during the pouring process of the door ring beam, resulting in subsequent grouting failure. These process defects inevitably cause severe water leakage

If there are no reliable waterproof and plugging measures, groundwater will invade the tunnel, affecting its internal structure and auxiliary pipelines, and even endangering the later operation and maintenance, reducing the service life of the tunnel

[0003] At present, the domestic treatment of leaking water from ring beams of portals usually uses single chemical material grouting such as epoxy resin for plugging. However, single chemical material grouting not only consumes a lot of manpower, but also consumes a lot of materials, with a low one-time success rate and high probability of re-leakage. , and will inevitably pollute the finished concrete structure

Therefore, it is difficult to meet the needs of on-site construction in terms of safety, quality, cost, management, and work efficiency by using the traditional waterproofing process and plugging process that only rely on concrete itself.

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