Foaming agent for earth pressure balance shield machine

Abstract

The invention belongs to the field of foaming agent technology, and aims to solve the problem that the foam uniformity, stability, lubricity, permeability and other properties of the current domestic foaming agent cannot fully meet the requirements for foam in shield tunneling construction, and the adaptability has certain limitations. , providing a foaming agent for an earth pressure balance shield machine. It is prepared from sodium lauryl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-olefin sulfonate, modified silicone resin polyether emulsion, and water in a certain proportion. The foaming agent of the present invention has stable performance, good foaming effect, and long foam stabilization time, and can be well used for improving dregs in hard plastic and soft plastic expansive clays, and can improve the flow plasticity and stability of the excavated soil. Water-based, can prevent the compaction and adhesion of the soil, prevent the cutterhead from forming cakes, and rely on the support of air bubbles to maintain the pressure of the soil bin; its raw materials are easy to obtain and low in price, which effectively reduces construction costs; bulk chemical products are used, and the product is pollution-free , without any toxic and side effects on the muck and the surrounding environment.

Description

technical field [0001] The invention belongs to the technical field of foaming agents, and in particular relates to a foaming agent for an earth pressure balance shield machine. Background technique [0002] In recent years, subway tunnel projects have been excavated by a mechanical device called a shield machine. The type of shield machine currently used is mainly an earth pressure balance shield machine, which is characterized by using excavated muck as a support The stable medium of the excavation surface requires the muck as the supporting medium to have good plastic deformation, soft consistency and low permeability. Since the general soil cannot fully meet these characteristics, it needs to be improved. The technical point is to inject foam and other mixed materials into the front of the cutterhead of the shield machine and the soil bin, and then vigorously stir to improve the plasticity and stability of the excavated dregs. Mobility, reduce the water permeability of ...

AI Technical Summary

Problems solved by technology

[0003] In recent years, many domestic scientific research institutes have carried out research on foam adhesives, but most of the research directions are sandy pebble formations or sandy gravel formations, and there are few studies on foaming agents in hard plastic and soft plastic expansive clays. The foam agents used in similar formations are all imported products, which are expensive and the construction cost is high