Sand-layer grouting ground surface uplifting control method based on drilling collapse and induced splitting

Abstract

The invention provides a ground surface uplifting control method based on induced splitting and collapsing drilled holes. Aiming at advanced pre-grouting reinforcement of a transverse channel passingthrough a sand layer in subway engineering, the purposes of controlling the slurry direction and lowering ground surface uplift are achieved by distributing collapsing-induced-splitting drilled holesand the collapsing drilled holes. Through the induced-splitting drilled holes, the formation stress of a target reinforcement area is lowered, the slurry direction is controlled, and slurry runout ofthe ground surface is prevented; through the collapsing drilled holes, a formation uplift buffering area is created, and ground surface uplift is lowered; and the induced-splitting drilled holes and the collapsing drilled holes are matched with a pipe shed, thus the grouting effect can be ensured, and meanwhile, ground surface uplift can be effectively controlled.

Description

technical field [0001] The invention mainly relates to a control method for surface uplift during the grouting reinforcement process of the sand layer of the cross channel of the subway project. Background technique [0002] In recent years, my country's subway projects have been put into construction one after another, and the control of various geological disasters has become a key problem to be solved urgently. Sand layer grouting reinforcement, especially in coastal cities, is a common technical problem in subway construction. Advance grouting reinforcement of the cross passage passing through the urban highway is the most difficult, and the main difficulties are as follows: [0003] (1) Water supply pipelines, gas pipelines, power pipelines and sewage pipelines are generally laid along urban roads, and the requirements for surface uplift caused by grouting are more stringent. [0004] (2) The burial depth of the transverse channel is shallow, and there is a lack of su...

AI Technical Summary

Problems solved by technology

[0004] (2) The burial depth of the transverse channel is shallow, and there is a lack of sufficient grout-stop formation during the grouting process, so the grout is easy to escape from the surface; at the same time, the final grouting pressure is not high, and the grouting effect is not good

[0005] (3) The compressibility of the sand layer itself is not high, and the grouting will easily cause the surface to rise too much, and the grouting is more difficult

Images