Existing lining structure reinforcing method

Abstract

The invention discloses a method for reinforcing an existing lining structure, which comprises the following steps of: determining a deformation position of a lining in a tunnel, and selecting at least one coverage area along the inner wall of the lining at the deformation position; a reinforcing layer formed by pouring reinforcing material slurry is arranged in the covering area, the reinforcing layer with the UHPC reinforcing material slurry can effectively control continuous deformation of the duct piece, the reinforcing layer has a certain thickness, the section height of a pressed area on the inner side of the duct piece can be effectively increased, deformation of a pressed part on the inner side is controlled, then deformation of a pulled part on the inner side is indirectly controlled, and the service life of the duct piece is prolonged. Therefore, the overall rigidity and bearing capacity of the lining are improved.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering, and in particular to a method for reinforcing an existing lining structure. Background Art

[0002] Damage, cracking, water leakage and other defects in the tunnel lining will lead to a decrease in the overall bearing capacity and durability of the segment, posing a great threat to tunnel safety and normal operation. Excessive deformation of the lining often requires reinforcement measures on the inner surface. There are currently two main methods on the market: 1) pasting fiber cloth (FRP); 2) pasting steel plates. The former can effectively control the tensile deformation of the inner side of the segment, but the stiffness of the overall structure of the segment is not significantly improved, and it is not easy to control the overall deformation; although the latter can improve the overall stiffness of the structure and control deformation, it faces the problems of heavy weight and difficult construction, and pasting steel plates often requires planting steel bars, and drilling holes for planting steel bars can easily cause damage to the concrete segment structure. At the same time, both of the above reinforcement methods have disadvantages such as poor high temperature resistance and durability, and the organic bonding materials (epoxy resin glue) used are prone to aging, resulting in cracking and peeling of the reinforcement layer, requiring repeated reinforcement, which greatly increases the maintenance cost. Summary of the invention

[0003] A first aspect of an embodiment of the present invention is to provide a method for reinforcing an existing lining structure.

[0004] An embodiment of the first aspect of the present invention provides a method for reinforcing an existing lining structure, comprising the following steps: determining the position of lining deformation in a tunnel, and selecting at least one covering area along the inner wall of the segment at the position of the deformation; providing a reinforcement layer formed by casting a reinforcement material slurry in the covering area; wherein the reinforcement material slurry is made of UHPC material.

[0005] The reinforcement layer with UHPC reinforcement material slurry can effectively control the continuous deformation of the lining. The reinforcement layer has a certain thickness, which can effectively increase the cross-sectional height of the inner compression zone of the lining, control the deformation of the inner compression part, and then indirectly control the deformation of the inner tension part, thereby improving the overall stiffness and bearing capacity of the lining.

[0006] By selecting at least one coverage area, targeted construction settings can be made according to the different degrees of damage in the tunnel. The work can be carried out in sections or individually, making the overall construction operation more flexible and able to cope with different operational requirements, while avoiding the problem of a single overly large construction section causing trouble to the overall construction.

[0007] When the lining deformation is damaged, reinforcing material slurry is injected into the damaged position until it is flush with the inner wall of the segment, and a repair layer is formed after cooling and solidification; when the lining deformation is cracked, reinforcing material slurry is injected into the cracked gap and the damaged position until the crack is completely sealed; when the lining deformation is convex, reinforcing material slurry is not injected into the convex position.

[0008] When cracks appear on the inner wall of the lining, workers inject reinforcement slurry at individual points to pre-fill the cracks and bond the broken walls inside the lining, so that the narrow cavity inside the lining disappears and the lining becomes integrated again.

[0009] When the inner wall of the lining bulges outward, no shaping or smoothing treatment is performed to ensure the structural stability and integration of the lining as much as possible, so that the lining can drive the reinforcement layer when it continues to deform, so that the material properties of the UHPC material of the reinforcement layer can be fully exerted.

[0010] A method for reinforcing an existing lining structure also includes: roughening the inner wall of the lining in the covering area, and then spraying mortar on the roughened inner wall of the lining.

[0011] In this technical solution, the inner wall of the lining in the covered area is roughened to increase the unevenness of the inner wall, which helps to increase the bonding strength between the reinforcement layer and the pipe segment. Then, by injecting mortar, the bonding strength between the reinforcement layer and the lining can be further increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the present invention;

[0013] The corresponding relationship between the reference numerals and the component names is as follows:

[0014] 1 lining, 2 reinforcement layer, 3 repair layer, 4 reinforcement steel bar DETAILED DESCRIPTION

[0015] Specific implementation steps:

[0016] Step 1: Pour UHPC into the severely cracked parts of the lining for repair;

[0017] Step 2: Sandblasting, roughening, etc. are performed on the inner surface of the lining;

[0018] Step 3: Design the guide rail along the tunnel axis in advance and make the sliding steel mold. After installation, inject the UHPC reinforcement material slurry into the cavity between the steel mold and the lining and fill it up. The thickness should be more than 5 cm (actual thickness depends on the reinforcement design drawings).

[0019] Step 4: The next day, the formwork can be removed to complete the reinforcement of the current covered area, and the steel formwork can be slid to the next covered area in the tunnel for construction.

Claims

1. A method for reinforcing an existing lining structure, characterized in that: The method comprises the following steps: determining the position of the tunnel lining deformation, and selecting at least one covering area along the inner wall of the lining at the deformed position; arranging a reinforcement layer cast by reinforcement material slurry in the covering area; wherein the reinforcement material slurry is made of UHPC material.

2. The method for reinforcing an existing lining structure according to claim 1, characterized in that: When the lining is deformed into damage, reinforcing material slurry is injected into the damaged position until it is flush with the inner wall of the lining, and a repair layer is formed after cooling and solidification; when the lining is deformed into cracks, reinforcing material slurry is injected into the cracked gaps and damaged positions until the cracks are completely sealed; when the lining is deformed into convexity, reinforcing material slurry is not injected into the convex position.

3. The method for reinforcing an existing lining structure according to claim 1, characterized in that: The step of selecting at least one coverage area specifically includes: dividing the deformed lining and the inner wall around it into coverage areas along the circumferential direction of the tunnel.

4. The method for reinforcing an existing lining structure according to claim 1, characterized in that: Specifically include: Setting up a steel formwork in the tunnel corresponding to the covered area, and forming a casting cavity between the steel formwork and the inner wall of the lining; Reinforcement material slurry is injected into the casting cavity.

5. The method for reinforcing an existing lining structure according to claim 5, characterized in that: The step of setting up the steel mold in the tunnel corresponding to the coverage area specifically includes: when the coverage area is one, placing the steel mold on the ground of the tunnel corresponding to the coverage area; when the coverage area is more than two, placing a guide rail on the ground along the axial direction of the tunnel, slidably installing the steel mold on the guide rail, and moving it between adjacent coverage areas.

6. The method for reinforcing an existing lining structure according to claim 1, characterized in that: Also includes: The inner wall of the lining in the covering area is roughened, and then mortar is sprayed on the roughened inner wall of the lining.

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