A shield synchronous grouting construction material

Abstract

The invention discloses a shield synchronous grouting construction material including, by weight, 200-300 parts of composite Portland cement, 400-600 parts of fly ash, 50-80 parts of 200-mesh calcium based bentonite, 1200-1300 parts of grading river sand, 0.4-0.6 parts of hydroxypropylmethyl cellulose, 0.5-3 parts of a water reducer, 0.3-1 part of a retarder, 1-3 parts of an early strength agent and 16-24 parts of a volume stabilizing agent. Through reasonable adjustment of composition and content of the components, the compressive strength, bleeding ratio, setting time and flowability of the construction material are controlled, so that the construction material has long initial setting time, is quick in early strength development, is not liable to dissociation, has good volume stability, can effectively fill in gaps in buildings and prevent floatation and deformation of tunnel segments, has good flowability and anti-dispersing property, and is easy to transport and to store for a long period.

Description

technical field [0001] The invention relates to the technical field of tunnel construction materials, in particular to a shield synchronous grouting construction material. Background technique [0002] During the construction of the shield tunnel, when the shield tail comes out of the assembled shield segment, it will inevitably cause a building gap between the segment lining and the soil. At this time, timely shield tail grouting is required to prevent The soil around the shield segment is loosened, and at the same time, the wrapping effect of the soil on the lining structure of the shield segment is strengthened, so as to avoid the phenomenon of local stress concentration in the segment structure due to the lack of necessary resistance. Shield tail grouting refers to that in the process of shield tunneling construction, after the tunnel lining segments are assembled and the tunnel comes out of the shield tail, under a certain grouting pressure, an appropriate amount of gro...

AI Technical Summary

Problems solved by technology

Synchronous grouting is currently the most used synchronous grouting in the construction of shield tunnels in my country. There are many defects in the construction of synchronous single grouting: 1. The early strength of synchronous single grout is low, and the chemical stability is lacking in the later stage. It is easy to segregate, and cannot effectively control the buoyancy of the tunnel after it breaks away from the shield tail and maintain the longitudinal stability of the tunnel in the later stage; 2. The single liquid slurry is easy to segregate, causing difficulties in transportation and storage

Images