Thermal insulation method for high-ground-temperature tunnel surrounding rocks through grouting

Abstract

The invention discloses a thermal insulation method for high-ground-temperature tunnel surrounding rocks through grouting and belongs to the field of tunnels and underground engineering. The method comprises the steps of determining a grouting area according to geological conditions, defining the radius of a damage area and the radius of a perturbation area as d1 and d2, designing the grouting slurry mixing ratio of the damage area, and obtaining grouting slurry which meets performance requirements of the damage area; designing the grouting slurry mixing ratio of the perturbation area, and obtaining grouting slurry which meets performance requirements of the perturbation area; after a tunnel is excavated, conducting preliminary bracing before the excavation deformation, drilling holes at certain intervals by adopting the top-down segmented grouting method, clearing the holes, and arranging grouting plugs in segmented mode; when the surrounding rock deformation is stable after the bracing is conducted, conducting segmented grouting by adopting the top-down segmented grouting method, taking out the grouting plugs after the perturbation area grouting is completed, and then conducting grouting on the damage area; spraying a layer of polyurethane resin rigid foam at the outer side of the perturbation area; sealing the holes after the grouting is completed.

Description

technical field [0001] The invention belongs to the field of tunnels and underground engineering, and in particular relates to a method for grouting heat insulation of surrounding rocks of tunnels with high ground temperature. Background technique [0002] Many engineering projects such as deep buried tunnels, construction of hydropower stations, resource mining and deep national defense projects will face the dilemma of high ground temperature, which will have various adverse effects and hazards on tunnel engineering. High temperature will affect the physical and mechanical properties of the tunnel support structure, affect the structural stability of the primary and secondary masonry, and reduce the bearing capacity and durability of the lining structure system. The high-temperature surrounding rock releases energy through the tunnel face towards the tunnel, which will cause difficulties in tunnel construction. At present, as long as the lining and support structure of hi...

AI Technical Summary

Problems solved by technology

High temperature will affect the physical and mechanical properties of the tunnel support structure, affect the structural stability of the primary and secondary masonry, and reduce the bearing capacity and durability of the lining structure system

The high-temperature surrounding rock releases energy through the tunnel face towards the tunnel, which will lead to difficulties in tunnel construction

At present, as long as the lining and support structure of high ground temperature tunnels is developed from the inside of the support structure in China, thermal insulation materials are generally filled between the primary and secondary constructions to reduce the internal temperature of the tunnel, but this does not prevent the heat from flowing into the tunnel. transfer