Method for strengthening insulation protection net in unlined tunnel

Abstract

The invention discloses a method for reinforcing an insulating protection net in an unlined tunnel. The method comprises the following steps that the insulating protection net is spread on surroundingrock of the unlined tunnel, and a plurality of anchor backing plates are fixed to the surrounding rock through meshes of the insulating protection net, that is, the insulating protection net is reinforced. The anchor backing plates are each in a circular ring shape, and the outer diameters of the anchor backing plates are not smaller than 3 times the side lengths of the meshes. The method for fixing the insulating protection net through the anchor backing plates has the characteristics of rapidness, simpleness and convenience, and the requirement on short tunnel protection construction periodcan be met. The adopted anchor backing plates have the characteristics of practicability and attractiveness, abrasion of the insulating protection net can be effectively reduced, and the service lifeis prolonged. The adopted anchor backing plates adopt galvanized steel plates, and transition chamfers are processed at the edges.

Description

technical field

[0001] The invention relates to a method for strengthening an insulating protection net in a tunnel without lining. Background technique

[0002] Many old tunnels have no lining and have reached the development stage, and there are problems such as falling blocks and cracks, which seriously affect driving safety. Especially, the anti-falling reinforcement of electrified tunnels requires insulating materials and the construction time is short. The existing reinforcement methods are as follows: Concrete, carbon fiber mesh, metal mesh, etc. are all difficult to meet the reinforcement requirements. The former requires too long to open the skylight, and the latter two have problems of conductivity and electrification. use The insulating protective net made of para-aramid fiber has the characteristics of high strength, corrosion resistance, good insulation, flame retardancy, and convenient construction, and is suitable for the application of tunnel reinforcement....

Examples

Embodiment 1

[0025] Embodiment 1, use the anchor backing plate to The insulation protection net is reinforced in the tunnel

[0026] The materials used are as follows:

[0027] Anchor plate, the schematic diagram of which is shown in figure 1 As shown, it is made of galvanized steel sheet in a circular shape with an outer diameter of 180mm, an inner diameter of 25mm, and a thickness of 10mm, and the upper and lower surfaces have the same chamfer as the sides, and the radius of the chamfer is 3mm, Such as figure 2 shown.

[0028] Bolt: Hollow full-length grouted bolt is used, and the anti-corrosion adopts hot-dip galvanizing process. The diameter of the bolt is 25mm, and the length is 1-2.5m (including the exposed section). The specific design length is determined according to the test report of the surrounding rock stress circle.

[0029] Suture rope: use diameter 9mm The rope is used as a sewing rope.

[0030] Auxiliary bolt: used to make the protective net better cling to the su...

technical field

[0001] The invention relates to a method for strengthening an insulating protection net in a tunnel without lining. Background technique

[0002] Many old tunnels have no lining and have reached the development stage, and there are problems such as falling blocks and cracks, which seriously affect driving safety. Especially, the anti-falling reinforcement of electrified tunnels requires insulating materials and the construction time is short. The existing reinforcement methods are as follows: Concrete, carbon fiber mesh, metal mesh, etc. are all difficult to meet the reinforcement requirements. The former requires too long to open the skylight, and the latter two have problems of conductivity and electrification. use The insulating protective net made of para-aramid fiber has the characteristics of high strength, corrosion resistance, good insulation, flame retardancy, and convenient construction, and is suitable for the application of tunnel reinforcement....

Examples

Embodiment 1

[0025] Embodiment 1, use the anchor backing plate to The insulation protection net is reinforced in the tunnel

[0026] The materials used are as follows:

[0027] Anchor plate, the schematic diagram of which is shown in figure 1 As shown, it is made of galvanized steel sheet in a circular shape with an outer diameter of 180mm, an inner diameter of 25mm, and a thickness of 10mm, and the upper and lower surfaces have the same chamfer as the sides, and the radius of the chamfer is 3mm, Such as figure 2 shown.

[0028] Bolt: Hollow full-length grouted bolt is used, and the anti-corrosion adopts hot-dip galvanizing process. The diameter of the bolt is 25mm, and the length is 1-2.5m (including the exposed section). The specific design length is determined according to the test report of the surrounding rock stress circle.

[0029] Suture rope: use diameter 9mm The rope is used as a sewing rope.

[0030] Auxiliary bolt: used to make the protective net better cling to the su...

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