Multi-pass waterproof sealing method for dewatering well of mass raft foundation

Abstract

A multi-channel waterproof plugging method for a thick and large raft foundation dewatering well, using a steel casing with a water stop ring and an end blocking plate and an inner drainage grouting core pipe to pour expansive concrete in the steel casing as the first One-step sealing; use cement slurry to quickly inject into the pores of the gravel filling body in the dewatering well and the surrounding soil body to form a cement slurry filling body as the second waterproof sealing; use high-strength cement-based grouting material and sealing material filled at the top of the steel casing The steel flange blocking plate on the top of the steel casing is used as the third waterproof sealing to realize three sealing measures, the success rate of the first sealing is high, and the hidden danger of leakage caused by the failure of sealing and the cost caused by the secondary treatment are avoided high and low efficiency. And it does not affect the overall precipitation operation of the foundation, and has little impact on the construction of the main structure.

Description

[0001] Technical field: [0002] The invention belongs to the professional technical field of reinforced concrete, and relates to a multi-channel waterproof plugging method for a dewatering well of a thick and large raft foundation. [0003] Background technique: [0004] In the existing high-rise building foundation pit dewatering projects, the dewatering wells in deep-buried large-scale basements are mostly blocked with high-strength concrete or cement grouting by indwelling steel casings. There are two main technical solutions as follows: [0005] 1. If figure 1 As shown, the cement-free sand-pipe dewatering well is constructed during the foundation excavation stage, and then the steel casing is set during the construction of the raft foundation cushion, and the concrete pouring of the raft foundation is completed while the dewatering is continued. Withdraw in time, fill in with high-strength concrete added with early-strength agent, and use the waterproof performance of h...

AI Technical Summary

Problems solved by technology

[0013] The purpose of the present invention is to provide a multi-channel waterproof plugging method for thick and large raft foundation dewatering wells, which solves the hidden dangers of quality and safety in the sealing and leakage of raft foundation tube wells when the groundwater level is high. The failure of plugging leads to poor quality assurance of secondary treatment, high cost, and low efficiency.

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