Tunnel antifreeze and thermal insulation structure based on phase change temperature-adjusting concrete and its construction and operation method

Abstract

The invention discloses a tunnel anti-freeze heat-insulation structure based on phase change temperature adjusting concrete and a construction method. The tunnel anti-freeze heat-insulation structure comprises a primary tunnel lining, a waterproof plate, a secondary tunnel lining and a fireproof plate which are sequentially arranged on the tunnel cavern wall from outside to inside. Concrete of the secondary tunnel lining contains porous lightweight aggregate and phase change capsules. A heating device is sandwiched between the secondary tunnel lining and the waterproof plate. The porous lightweight aggregate and a phase change material are combined with an active heat supply technology, the problems that upper underground water of tunnel surrounding rocks melts while lower underground water of the tunnel surrounding rocks is frozen are solved, and the freezing damage to tunnels is completely eliminated; the energy storage and temperature adjusting functions of the phase change material and the heat insulation performance of the porous lightweight aggregate are utilized, and purchase cost and operation cost are reduced; and in addition, the porous lightweight aggregate and the phase change material are directly doped into concrete, the excavation radius of the tunnels does not need to be increased, and the construction cost is reduced.

Description

technical field [0001] The invention relates to a thermal insulation structure of a tunnel in a cold region, in particular to a tunnel antifreeze thermal insulation structure based on phase-change temperature-regulating concrete and a construction and operation method. Background technique [0002] In the prior art, in order to prevent freezing damage of tunnels in cold regions, a certain thickness of insulation layer is laid on the inner surface of the second lining of the tunnel. However, it is found in engineering applications that the existing insulation layer has the following shortcomings and deficiencies: [0003] The cost of thermal insulation materials is high, which greatly increases the construction cost of the tunnel. Taking polyurethane thermal insulation materials with a thickness of 5cm as an example, the cost per square meter is about 300 yuan, and the vertical length is about 6,000 yuan per linear meter; [0004] The service performance is declining yea...

AI Technical Summary

Problems solved by technology

[0005] The air temperature in the tunnel and the temperature of the surrounding rock are different in time and space. As a solid insulation material, the polyurethane insulation layer cannot meet the synchronization of freezing and melting of the surrounding rock behind the tunnel lining at different heights on the same section.

During the spring thaw period, the surrounding rock at the top of the tunnel melts first, and the surrounding rock at the arch foot melts later, which prevents the groundwater behind the tunnel lining from being discharged into the longitudinal drainage ditch, which easily causes leakage, icing and icing on the surface of the tunnel lining. During the freezing period, the surrounding rock at the bottom of the tunnel freezes first, then the surrounding rock at the top freezes, and the groundwater above the tunnel cannot be discharged into the longitudinal drainage ditch, which also causes diseases such as leakage, icing, and icing on the tunnel lining surface;

[0006] ④ Polyurethane insulation materials occupy the tunnel space. In order to meet the requirements of the tunnel building boundary, it is necessary to expand the excavation size of the tunnel surrounding rock, which will increase the construction cost and prolong the construction period, and is detrimental to the stability of the tunnel surrounding rock.

Images