Slow-release grouting material for steel shell immersed tube grouting and construction method of slow-release grouting material

Abstract

The invention discloses a slow-release grouting material for steel shell immersed tube grouting and a construction method of the slow-release grouting material, and the slow-release grouting materialfor steel shell immersed tube grouting is composed of quick-hardening Portland cement, microbeads, superfine slag powder, quartz sand, a composite functional component and water. The composite functional components comprise an expanding agent, a slow-release water reducing agent, an early strength agent, a quick-acting defoaming agent, a rheological agent, a plastic expanding agent and a slump retaining agent, all the components (except water) are fully premixed into uniform dry powder in a professional factory, the grouting material dry powder and water are stirred in a container by a handheld stirrer according to a specified proportion, wherein the stirring time is not shorter than 3 min, uniform slurry is obtained by stirring, and after standing for not less than 5 minutes, and theuniform slurry can be pumped and grouted. The slow-release grouting material for steel shell immersed tube grouting has the characteristics of good fluidity, long fluidity retention time (more than or equal to 5 hours), accurate vertical expansion rate control, early strength, high strength and the like, and can be compactly filled in a gap between self-compacting concrete and a steel shell in a steelshell immersed tube.

Description

technical field [0001] The invention belongs to the field of building materials, and particularly relates to a slow-release grouting material for filling the gap between concrete and the wall of the steel immersed tube in a steel shell immersed tube and a construction method thereof. Background technique [0002] In underwater tunnels, steel immersed tunnels are a commonly used tunnel form, which is constructed by pouring and filling self-compacting concrete between double steel shells. In the steel shell, the self-compacting concrete poured in this structure will shrink during the process of setting and hardening due to poor exhaust and insufficient pouring, resulting in gaps and seams between the concrete and the steel shell. In order to ensure that the load capacity of the steel shell immersed tube is not affected, and to prevent harmful media from accumulating in these gaps and eroding the concrete and steel shell, it is necessary to fill these gaps with grout. Due to t...

AI Technical Summary

Problems solved by technology

In order to obtain super-long slump retention, fluid cement-based materials often use retarders such as sodium gluconate, but a single retarder often cannot achieve super-long slump retention and affects setting time and early (1d) strength

The current national standard "Technical Specifications for the Application of Cement-based Grouting Materials" (GB / T 50448-2015) requires the vertical expansion rate of grouting materials to be 0.10 to 3.50% in 3 hours, and the difference between the expansion rates in 24 hours and 3 hours is 0.02 ~0.50%, the limit on the expansion rate is relatively broad, while the grouting material for steel shell immersed tube tunnel grouting has more detailed and strict requirements on this technical index, which cannot be achieved only by conventional technical means: for the setting time exceeding For a long slurry system, only plastic expansion agent is used to meet the 3h vertical expansion rate, the difference between the 24h and 3h expansion rate will often exceed the standard, and the slurry will often shrink too much after hardening to achieve the construction purpose

In the searched scientific papers and patents, no grouting material that can meet the requirements of the above indicators at the same time was found

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