High-performance synchronous grouting modifier for shielding construction as well as preparation method and application thereof

Abstract

The invention discloses a high-performance synchronous grouting modifier for shielding construction as well as a preparation method and application thereof. The high-performance synchronous grouting modifier for the shielding construction comprises the following components: 1-1.5% of a water reducing agent, 3-4% of a thickener, 0.5-1.0% of an antifreezing agent and the balance of water, wherein the water reducing agent is HSB aliphatic efficient water reducing agent; the thickener comprises bentonite and hydroxypropyl methylcellulose according to a mass ratio of 1:(0.8-1.2). The high-performance synchronous grouting modifier for the shielding construction improves the workability, the dilution resistance and the dispersion resistance of a synchronous grouting slurry and lowers the volume shrinkage of the synchronous grouting slurry, so that synchronous grouting can still be constructed under a negative temperature condition; the high-performance synchronous grouting modifier can enable the synchronous grouting slurry to timely provide the strength, and tightly fill a shield tail gap. The synchronous grouting modifier consists of several environment-friendly and harmless components, so that the synchronous grouting modifier does not pollute the surrounding environment during the shielding construction while the synchronous grouting quality is improved.

Description

technical field [0001] The invention relates to the field of mud-water balance shield construction materials, in particular to a high-performance synchronous grouting modifier for shield tunneling and its preparation method and application. Background technique [0002] During muddy water shield excavation, there will be a certain gap between the segment and the surrounding soil. At this time, in order to suppress the deformation of the surrounding soil and control the ground subsidence, it is necessary to continuously inject a Provide grouting material with a certain strength within the specified time to play the role of filling support, that is, synchronous grouting for shield tunneling. There are many types of synchronous grouting for shield tunneling, but the most commonly used one is single-liquid grouting. The quality of synchronous grouting is the key to ensuring the safety and durability of shield tunneling. However, due to the existence of groundwater and other unce...

AI Technical Summary

Problems solved by technology

There are many types of synchronous grouting for shield tunneling, but the most commonly used one is single-liquid grouting. The quality of synchronous grouting is the key to ensuring the safety and durability of shield tunneling. However, due to the existence of groundwater and other uncertain factors underground, ordinary grouting Synchronous grouting has the following problems: ①The workability of synchronous grouting slurry is poor. When the fluidity increases, segregation will occur. When the fluidity decreases, it is not conducive to long-distance pumping; ②When the groundwater is abundant, synchronous The grouting grout is very easy to dilute, and the grout is washed away by groundwater, resulting in a large loss of cement and fine components, and the actual grouting quality cannot reach the expected effect; ③The volume shrinkage of the grout is large after hardening, so that the gap at the tail of the shield cannot be completely filled; ④In the cold Freeze-thaw damage is prone to occur after synchronous grouting

[0003] The grouting materials in the prior art generally eliminate the large volume shrinkage caused by the hardening of the grout by adding a volume expansion agent, so that the shield tail pores cannot be completely filled

After the expansion agent is mixed, there are strict requirements on the stirring and grouting of the grouting slurry. If the stirring is not uniform, the hardened grout will be deformed unevenly and the cracking will be aggravated.

At the same time, after the expansion agent is added to the grouting grout, there will also be a problem that the support strength will decrease after the grout hardens

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