New grouting fluid after shield tail wall with anti-loss

Abstract

The invention relates to a novel grouting slurry for a shield machine and a shield tail wall with loss prevention. The novel grouting slurry for the shield machine and the shield tail wall with loss prevention comprises cement mortar and external additive. The cement mortar is mixed with cement, flyash, bentonite, sand and tap water. The external additive comprises material A and liquid B, and thematerial A is bentonite, organic white clay and alumina, the liquid B is water glass or small cationic quaternary ammonium salt. The cement mortar mixing process is mixed with the material A and is stirred evenly. The cement mortar mixed with the material A is transported to the shield tail by pumping and slurry transport, and pumped into a grouting tank of the shield tail, the cement mortar is obtained by mixing with the liquid B in the tank and pumped into the gap of the shield tail through a grouting pump. The novel grouting slurry for the shield machine and the shield tail wall with lossprevention has the advantages that the novel grouting slurry for the shield tail wall is not prone to being diluted by water, can fill the gap of the shield tail in time, and is not prone to losing tothe pressure chamber of shield excavation face, thus the filling effect of slurry on the gap of the shield tail is ensured, and the construction difficulty of the shield tail slurry channeling into apressure chamber of the excavation surface along the narrow gap between a shield shell and a surrounding rock in the shield tunnelling process in a weathered rock formation is solved.

Description

technical field [0001] The invention relates to a novel shield tail wall grouting fluid capable of preventing loss, and belongs to the technical field of underground engineering construction. Background technique [0002] Due to the vast territory of our country, the construction of shield tunnels has encountered various geological conditions, from the soft soil foundation in Shanghai in the Yangtze River Delta to the pebble and weathered rock foundation in Chengdu in the upper reaches of the Yangtze River, to the soft soil and shallow buried weathered rock in the Pearl River Delta. Upper soft and lower hard strata formed by rocks. Especially in weathered rock formations, due to the good stability of the formation itself, the gap between the shield shell and the formation formed by the diameter of the cutter head of the shield machine slightly larger than the diameter of the shield shell cannot be automatically closed in a short time, and the slurry injected into the tail of...

AI Technical Summary

Problems solved by technology

[0003] The present invention proposes a new type of grouting fluid behind the tail wall of the shield that prevents loss, and aims to solve the long-term problems of shield tunneling in stable formations in my country when the grouting fluid in the shield tail gap is lost and the segment is lost. Quality problems such as floating, segment misalignment, cracking, etc.