Stress-loading three-dimensional test device and method for analyzing stability of shield tunneling faces

Abstract

The invention relates to the field of tunnel shields and discloses a stress-loading three-dimensional test device and method for analyzing the stability of shield tunneling faces. The device comprisesa shell, a confining-pressure simulation mechanism, a synchronous stress-loading mechanism, at least two parts of filler and a measuring component, wherein the shell comprises a bottom wall, a side wall and a top wall; the confining-pressure simulation mechanism comprises a pressurizing plate and lifting machines; the pressurizing plate is connected at the inner side of the side wall in a slidingmanner, and the bottom wall, the side wall and the pressurizing plate are enclosed into a filler cavity; all the lifting machines lift and drive the pressurizing plate to move up and down synchronously; the synchronous stress-loading mechanism comprises an air compressor, a cylindrical barrel wall, a first air bag in the cylindrical barrel wall, a semicylindrical barrel wall and a second air bagin the semicylindrical barrel wall; the two air bags are mutually communicated, and the air compressor pressurizes the two air bags simultaneously; filler fills from bottom to top in a layering manner, and the colors of adjacent layers are different; the measuring component comprises a pressure sensor, an acquisition instrument and a processor which are arranged in the two air bags. The stress-loading three-dimensional test device and method are used for studying the displacement distribution, critical slip state and minimum supporting pressure of soil bodies of the shield tunneling faces.

Description

technical field [0001] The invention relates to the technical field of mud-water shield tunneling, in particular to a stress-loading three-dimensional test device and method for stability analysis of a shield tunneling surface. Background technique [0002] In the prior art, when analyzing the stability of the tunnel shield tunneling face, the soil is usually cut longitudinally or transversely, and the test is carried out by plane loading to study the soil pressure distribution of the soil in front of the tunneling face and the loss of the tunneling surface. For the slippage of the soil ahead when the tunnel is stable, there are many studies on the longitudinal section. However, simply studying the longitudinal section or cross section of the tunnel cannot reflect the entire situation of the soil ahead when the excavation face is unstable. Even if the longitudinal section and cross section of the tunnel excavation surface are studied at the same time on different test device...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, when analyzing the stability of the tunnel shield tunneling face, the soil is usually cut longitudinally or transversely, and the test is carried out by plane loading to study the soil pressure distribution of the soil in front of the tunneling face and the loss of the tunneling surface. The slippage of the soil in front of the tunnel when it is stable, among which there are many studies on the longitudinal section. However, simply studying the longitudinal section or cross section of the tunnel cannot reflect the entire situation of the soil ahead when the excavation face is unstable.

Even if the longitudinal section and cross section of the tunnel excavation surface are studied at the same time on different test devices, and then the combined analysis is carried out, there are also differences in the stress environment, and the loading synchronization is not clear, which leads to the fact that the three-dimensional soil cannot be truly reflected when the tunnel excavation faces boundary instability. Stress-strain relationship, the reliability of the analysis results is also doubtful

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