Method for predicting stability of tunnel grout-stopping wall under full-section grouting

Abstract

The invention relates to the field of infrastructure construction, in particular to a method for predicting the stability of a tunnel grouting-stopping wall under full-section grouting, which comprises the following steps: 1) measuring the vault elevation Z1 and the bottom elevation Z2 of a tunnel; (2) measuring and calculating the ground elevation Z3 of the water and mud bursting position of the tunnel, the mud surface elevation Z4 after water and mud bursting and the underground water level Z5; 3) acquiring characteristic data of the water-inrush and mud-inrush soft soil body below the underground water level: saturation weight gamma sat, effective weight gamma ', internal friction angle and static soil pressure coefficient K0; (4) the horizontal soil pressure sigma1x at the top face of the grout stopping wall, the horizontal soil pressure sigma2x at the bottom face of the grout stopping wall, the water pressure sigmaw1 at the top face of the grout stopping wall, the water pressure sigmaw2 at the bottom face of the grout stopping wall and the gravity G of the grout stopping wall are calculated; (5) the total horizontal thrust T borne by the grout stopping wall and the horizontal thrust resistance R of the grout stopping wall are calculated, and the stability of the grout stopping wall is judged according to R and T; if R is larger than or equal to T, it is judged that the grout stopping wall is in a stable state; and T, judging that the grout-stopping wall is in an unstable state.

Description

technical field [0001] The invention relates to the field of infrastructure construction, in particular to a method for predicting the stability of a grout stop wall of a tunnel under full-section grouting. Background technique [0002] When tunnels are excavated to weak zones such as fault fracture zones and intrusion contact zones, water and mud inrush disasters are likely to occur. Once the above-mentioned dangers occur in the tunnel, concrete grout-stop walls are generally used to support it, and then the grout-stop wall is used to carry out Grouting is performed on the entire section to reinforce the weak rock and soil mass behind. After the rock and soil mass is strengthened, the grout stop wall is gradually removed for excavation. However, when the grouting pressure of the grouting wall is too high or the thickness of the grouting wall is insufficient, the grouting wall may slide along the bottom of the tunnel to the outside of the tunnel, and then the retaining funct...

AI Technical Summary

Problems solved by technology

However, when the grouting pressure of the grouting wall is too high, or the thickness of the grouting wall is insufficient, the grouting wall may slide along the bottom of the tunnel to the outside of the tunnel, and then the retaining function of the grouting wall will fail

So far, the stability of the grout-stop wall under the action of grouting pressure is mostly judged by engineering experience, and there is no reliable theory to guide it.