Operation tunnel cavity renovation method

Abstract

The invention discloses an operation tunnel cavity renovation method, which comprises the following steps of: driving a reinforcing anchor rod into a renovation ring for stabilizing a tunnel lining and a tunnel primary support; filling the holes with foam concrete; a concrete foundation is arranged at a tunnel lining arch foot of the renovation ring, a steel plate base is pre-buried in the concrete foundation, and the steel plate base is connected with the tunnel lining through a reinforcing anchor rod; a corrugated steel plate arranged in a ring is erected between the two steel plate bases, the corrugated steel plate is arranged below the tunnel lining in the range of the renovation ring in a lining mode, and a pouring space is formed between the corrugated steel plate and the tunnel lining; and the pouring space is filled with waterproof mortar, and a waterproof layer is formed. Partial or whole-ring chiseling and rebuilding of the tunnel are not needed, time and labor are saved, efficiency is high, and influence on tunnel operation is small; and the holes are filled with foam concrete, the renovation ring structure adopts a reinforced anchor rod and corrugated steel plate reinforced structure, and a waterproof layer is arranged, so that the structure is stable, the waterproof effect is good, and the repairing quality is high.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel disease treatment, and in particular relates to a method for treating a cavity in an operating tunnel. Background Art

[0002] The voids behind the tunnel lining are hidden and potentially harmful. The voids will unload the load of the surrounding rock, causing the surrounding rock pressure to be redistributed, which will increase the ground pressure nearby and cause the tunnel structure to bear the bias load, resulting in stress concentration, which will cause insufficient structural bearing capacity, making the voids the focus of lining structure damage and even leading to collapse. Therefore, the research and application of void defect remediation solutions are of great significance to ensuring the safe operation of tunnels.

[0003] In the actual construction process, when voids appear behind the lining, the voids are currently mainly repaired by grouting. Although the slurry can play a repair role after solidification, the repair quality is low. Especially when the void is large, a single grouting method cannot meet the repair quality requirements. At present, to repair larger voids, partial or full ring chiseling and reconstruction are mostly adopted. This method is time-consuming and labor-intensive, and greatly affects the normal operation of the tunnel. In addition, the tunnel waterproofing board is generally located between the primary support and the lining. In order to repair the voids behind the primary support, existing conventional methods such as "opening skylights" and grouting filling require the removal of the waterproofing board. After implementation, the waterproofing performance of the tunnel will deteriorate, which is prone to secondary diseases such as water leakage. Summary of the invention

[0004] The present invention provides a method for repairing a cavity in an operating tunnel to solve the technical problems existing in the known technology. The method can be used to repair larger cavities with good repair quality and high efficiency.

[0005] The technical solution adopted by the present invention to solve the technical problems existing in the known technology is: a method for treating the cavity of an operating tunnel, which adopts the following steps:

[0006] S1. Detect the three-dimensional size of the tunnel cavity, and then draw lines on the lining surface in front of the cavity to determine the scope of the remediation ring according to the cavity size;

[0007] S2. Prefabricate repair materials according to the size of the tunnel and the size of the remediation ring; temporarily relocate existing lighting lines and network cables, and dismantle and remove related equipment;

[0008] S3. Drive reinforcing anchors into the regulation ring to stabilize the tunnel lining and primary support;

[0009] S4. Use foam concrete to fill the voids;

[0010] S5. A concrete foundation is set at the arch foot of the tunnel lining of the regulation ring, a steel plate base is embedded in the concrete foundation, and the steel plate base is connected to the tunnel lining by reinforcing anchors driven into step S3;

[0011] A corrugated steel plate arranged in a ring is erected between the two steel plate bases, and the corrugated steel plate is lined under the tunnel lining within the scope of the regulation ring, and a pouring space is formed between the two;

[0012] S6. Fill the grouting space with waterproof mortar to form a waterproof layer;

[0013] S7. After the construction is completed, restore the relevant equipment, lighting lines and network cables;

[0014] S8. Cleaning, inspection and acceptance.

[0015] When the cavity is a combined cavity composed of the cavity behind the primary support of the tunnel and the cavity behind the tunnel lining, the specific method of step S4 is: a large grouting hole is opened at the center of the cavity behind the primary support of the tunnel, and the corresponding primary support of the tunnel is broken; the grouting pipe is first extended into the cavity behind the primary support of the tunnel, and foam concrete is poured into it. After the grouting of the cavity behind the primary support of the tunnel is completed, a set volume of foam concrete is injected into the cavity behind the tunnel lining, and finally the large grouting hole is closed; a small grouting hole is opened at the edge of the cavity behind the tunnel lining, and foam concrete is injected into the cavity behind the tunnel lining to ensure that the cavity behind the tunnel lining is filled with a high degree of fullness, and then the small grouting hole is closed.

[0016] The fullness of the primary support cavity grouting should be above 85%, and the fullness of the lining cavity grouting should be above 95%.

[0017] In step S5, the corrugated steel plate is fixed to the tunnel lining by chemical anchor bolts.

[0018] In step S3, the anchor rods are reinforced at the arch foot and the cavity.

[0019] The specific method of filling the grouting space with waterproof mortar in step S6 is: opening grouting holes at the top and waist of the arch, pouring into the grouting gap from top to bottom and symmetrically, and closing the grouting holes after the overall pouring is completed.

[0020] In step S3, the corrugated steel plate is provided with a galvanized layer and is formed by splicing a plurality of blocks. Two adjacent blocks are overlapped and connected with high-strength bolts. Gaskets are provided on the high-strength bolts and chemical anchors. The connections between the high-strength bolts and chemical anchors and the corrugated steel plate are sealed with structural adhesive.

[0021] In step S5, the corrugated steel plates arranged in a ring are constructed symmetrically on both sides and closed at the top.

[0022] In the step S6, the waterproof mortar is epoxy resin mortar.

[0023] In the step S1, a geological radar is used to detect the three-dimensional size of the tunnel cavity.

[0024] The advantages and positive effects of the present invention are as follows: by adopting cavity grouting and adding a regulation ring structure, there is no need to partially or completely remove and rebuild the tunnel, which saves time and effort, is highly efficient, and has little impact on tunnel operation; and because foam concrete is used to fill the cavity, the regulation ring structure is reinforced with reinforced anchor rods and corrugated steel plates, and a waterproof layer is provided, the structure is stable, the waterproof effect is good, and the repair quality is high. Furthermore, the cavity grouting and the establishment of corrugated steel plates can be started at the same time, which can further shorten the construction period and reduce the impact on the normal operation of the tunnel; by reasonably arranging the filling grouting holes, the grouting fullness can be improved and the impact on the tunnel structure can be reduced; the use of foam concrete as the filling material of the renovation structure is convenient for pouring and can optimize the stress state of the lining; the use of epoxy grouting slurry as a waterproof layer can not only improve the waterproof performance of the tunnel, but also be closely combined with the corrugated steel plate to enhance the overall stability of the tunnel structure; the use of chemical anchors to fix the corrugated steel plate can stabilize the connection between the lining, the corrugated steel plate and the waterproof layer; the strengthening anchor rod with the end penetrating into the surrounding rock is driven into the tunnel lining, and the reinforced concrete foundation is connected to the tunnel lining, which can not only reinforce the weak points of the lining, but also enhance the stability of the connection between the renovation structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the application of the present invention;

[0026] Figure 2 for Figure 1 Structural cross-section of the cavity section;

[0027] Figure 3 for Figure 1 Structural cross-section of standard section;

[0028] Figure 4 The grouting drilling arrangement diagram of step S4 of the present invention;

[0029] Figure 5 It is a construction flow chart of the present invention.

[0030] In the figure: 1. Concrete foundation; 2. Reinforced anchor rods; 3. Chemical anchor bolts; 4. Tunnel lining; 5. Tunnel primary support; 6. Waterproof layer; 7. Corrugated steel plate; 8. Foam concrete; 9-1. Cavity behind tunnel primary support; 9-2. Cavity behind tunnel lining; 10-1. Large grouting hole; 10-2. Small grouting hole. DETAILED DESCRIPTION

[0031] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0032] See also Figure 1 to Figure 5 , a method for treating a cavity in an operating tunnel, using the following steps:

[0033] S1. Carry out three-dimensional size detection of tunnel voids, and then draw lines on the lining surface in front of it according to the size of the void to determine the scope of the remediation ring; usually geological radar is used to detect the three-dimensional size of tunnel voids.

[0034] S2. Prefabricate repair materials according to the size of the tunnel and the size of the remediation ring; temporarily relocate existing lighting lines and network cables, and dismantle and remove related equipment;

[0035] The repair material comprises a corrugated steel plate 7 hereinafter.

[0036] S3. Drive reinforcing anchor rods 2 into the regulation ring to stabilize the tunnel lining 4 and the tunnel primary support 5, and enhance the connection stability between the subsequent filling body, waterproof layer, concrete foundation and surrounding rock, and tunnel lining.

[0037] S4. Using foamed concrete 8 to fill the voids can fill the load gap, optimize the stress state of the lining, and prevent the development of voids.

[0038] When general concrete is used to fill the void in the vault, due to insufficient pouring pressure, concrete shrinkage and other reasons, it may not be in close contact with the surrounding rock and form a whole. Not only does it fail to fill the missing load and optimize the stress state of the lining, but its own weight also directly acts on the weak points of the lining, causing adverse effects. Foam concrete is light, high-strength, easy to pour, and has strong adhesion. It can fill the void more fully, and its own weight has little effect, which can better optimize the stress state of the lining.

[0039] S5. A concrete foundation 1 is set at the arch foot of the tunnel lining of the regulation ring, and a steel plate base is embedded in the concrete foundation 1. The steel plate base is connected to the tunnel lining through the reinforcing anchor rod 2 driven in step S3, which strengthens the connection between the concrete foundation and the tunnel lining, improves the stability of the foundation, and ensures that the corrugated steel plate and the waterproof layer are in a stable state.

[0040] The above-mentioned steel plate base provides a prerequisite for the installation of corrugated steel plates. A ring-shaped corrugated steel plate 7 is installed between the two steel plate bases. The corrugated steel plate and the steel plate base are connected with bolts. The corrugated steel plate 7 is lined under the tunnel lining 4 within the range of the regulation ring, and a pouring space is formed between the two.

[0041] S6. Fill the pouring space with waterproof mortar to form a waterproof layer 6, which can improve the overall waterproof performance of the tunnel.

[0042] S7. After the construction is completed, restore the relevant equipment, lighting lines and network cables;

[0043] S8. Cleaning, inspection and acceptance.

[0044] The construction of S4 and S5 basically does not conflict and can be carried out simultaneously.

[0045] The method of cavity grouting and adding repair rings eliminates the need to partially or completely remove and rebuild the tunnel, which saves time and effort, is highly efficient, and has little impact on tunnel operations. In addition, because foam concrete is used to fill the cavities, the repair ring structure is reinforced with reinforced anchor rods and corrugated steel plates, and a waterproof layer is set, the structure is stable, the waterproof effect is good, and the repair quality is high.

[0046] The more preferred solution of this embodiment is as follows:

[0047] See also Figure 1 and Figure 4 When the cavity is a combined cavity consisting of the cavity 9-1 behind the tunnel primary support and the cavity 9-2 behind the tunnel lining, the specific method of step S4 is:

[0048] A large grouting hole 10-1 is opened at the center of the cavity 9-1 behind the primary support of the tunnel, and the corresponding primary support of the tunnel is broken; the grouting pipe is first extended into the cavity 9-1 behind the primary support of the tunnel, and foamed concrete 8 is poured therein, and after the grouting of the cavity 9-1 behind the primary support of the tunnel is completed, a set volume of foamed concrete 8 is injected into the cavity 9-2 behind the tunnel lining, and finally the large grouting hole 10-1 is closed; a small grouting hole 10-2 is opened at the edge of the cavity 9-2 behind the tunnel lining, and foamed concrete 8 is injected into the cavity 9-2 behind the tunnel lining to ensure that the cavity behind the tunnel lining is filled with a high degree of fullness, and then the small grouting hole 10-2 is closed.

[0049] Basic principles of hole layout: large grouting holes should be arranged in the center of the primary support cavity as much as possible, and as few large grouting holes as possible should be set. However, if the circumferential range and radial height of the primary support cavity are large, more large grouting holes can be reasonably set; small grouting holes are generally set at the edge of the lining cavity, the grouting fullness of the primary support cavity should be above 85%, and the grouting fullness of the lining cavity should be above 95%.

[0050] By properly arranging the filling grouting holes, the grouting fullness of the combined cavity can be improved, and the impact on the tunnel lining, waterproof board and other structures can be reduced. Using foam concrete as the filling material for the renovated structure is convenient for pouring and can optimize the stress state of the lining.

[0051] In the step S5, the corrugated steel plate 7 is fixed to the tunnel lining 4 by using chemical anchor bolts 4, so that the connection between the tunnel lining 4, the corrugated steel plate 7 and the waterproof layer 6 can be stable.

[0052] In step S3, the anchor rods 2 are reinforced at the arch foot and the cavity. The reasons are as follows: the tensile stress at the arch foot is large, which is prone to lining cracks and water leakage; by reinforcing the weak parts with denser anchor rods, the associated diseases can be rectified; the end of the anchor rod penetrates deep into the surrounding rock, tightening the contact between the filling body and the surrounding rock, which can further optimize the stress state of the lining.

[0053] The specific method of filling the grouting space with waterproof mortar in step S6 is: opening grouting holes at the arch top and arch waist, pouring into the grouting gap from top to bottom and symmetrically, and closing the grouting holes after the overall pouring is completed. The two sides and the top are constructed at the same time, which is simple and fast.

[0054] In step S3, the corrugated steel plate 7 is provided with a galvanized layer, which has excellent corrosion resistance; the corrugated steel plate 7 is formed by splicing multiple blocks, two adjacent blocks are overlapped and connected with high-strength bolts, gaskets are provided on the high-strength bolts and chemical anchors, and the connection between the high-strength bolts and chemical anchors and the corrugated steel plate is sealed with structural adhesive, which can effectively improve the waterproof performance. The above structure can improve the strength and stability of the corrugated steel plate; the prefabricated gasket can prevent the overflow of the grouting grout and improve the waterproof performance of the corrugated steel plate to a certain extent.

[0055] In the step S5, the corrugated steel plate 7 arranged in a ring is constructed symmetrically on both sides and closed at the top, and both sides are constructed simultaneously, which has low difficulty and fast progress.

[0056] In step S6, the waterproof mortar adopts epoxy resin mortar, and uses epoxy grouting slurry as a waterproof layer, which can not only improve the waterproof performance of the tunnel, but also can be closely combined with the corrugated steel plate to enhance the overall stability of the tunnel structure. The epoxy resin mortar is mainly composed of epoxy resin and has high adhesion. The waterproof layer formed by it can stabilize the connection between the lining and the corrugated steel plate; it has high strength and can improve the overall safety performance of the tunnel; it has strong impermeability and can rectify the lining leakage problem caused by the combined voids.

[0057] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments, which are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can make many forms without departing from the scope of protection of the present invention and the claims, all of which fall within the scope of protection of the present invention.

Claims

1. A method for treating a cavity in an operating tunnel, characterized in that: Use the following steps: S1. Detect the three-dimensional size of the tunnel cavity, and then draw lines on the lining surface in front of the cavity to determine the scope of the remediation ring according to the cavity size; S2. Prefabricate repair materials according to the size of the tunnel and the size of the remediation ring; temporarily relocate existing lighting lines and network cables, and dismantle and remove related equipment; S3. Drive reinforcing anchors into the regulation ring to stabilize the tunnel lining and primary support; S4. Use foam concrete to fill the voids; S5. A concrete foundation is set at the arch foot of the tunnel lining of the regulation ring, a steel plate base is embedded in the concrete foundation, and the steel plate base is connected to the tunnel lining by reinforcing anchors driven into step S3; A corrugated steel plate arranged in a ring is erected between the two steel plate bases, and the corrugated steel plate is lined under the tunnel lining within the scope of the regulation ring, and a pouring space is formed between the two; S6. Fill the grouting space with waterproof mortar to form a waterproof layer; S7. After the construction is completed, restore the relevant equipment, lighting lines and network cables; S8. Cleaning, inspection and acceptance.

2. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: When the cavity is a combined cavity composed of the cavity behind the primary support of the tunnel and the cavity behind the tunnel lining, the specific method of step S4 is: a large grouting hole is opened at the center of the cavity behind the primary support of the tunnel, and the corresponding primary support of the tunnel is broken; the grouting pipe is first extended into the cavity behind the primary support of the tunnel, and foam concrete is poured into it. After the grouting of the cavity behind the primary support of the tunnel is completed, a set volume of foam concrete is injected into the cavity behind the tunnel lining, and finally the large grouting hole is closed; a small grouting hole is opened at the edge of the cavity behind the tunnel lining, and foam concrete is injected into the cavity behind the tunnel lining to ensure that the cavity behind the tunnel lining is filled with a high degree of fullness, and then the small grouting hole is closed.

3. The method for treating the cavity in an operating tunnel according to claim 2, characterized in that: The fullness of the primary support cavity grouting should be above 85%, and the fullness of the lining cavity grouting should be above 95%.

4. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: In step S5, the corrugated steel plate is fixed to the tunnel lining by chemical anchor bolts.

5. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: In step S3, the anchor rods are reinforced at the arch foot and the cavity.

6. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: The specific method of filling the grouting space with waterproof mortar in step S6 is: opening grouting holes at the top and waist of the arch, pouring into the grouting gap from top to bottom and symmetrically, and closing the grouting holes after the overall pouring is completed.

7. The method for treating the cavity in an operating tunnel according to claim 5, characterized in that: In step S3, the corrugated steel plate is provided with a galvanized layer and is formed by splicing a plurality of blocks, two adjacent blocks are overlapped and connected by high-strength bolts, and gaskets are provided on the high-strength bolts and chemical anchor bolts. The connections between high-strength bolts, chemical anchors and corrugated steel plates are sealed with structural adhesive.

8. The method for treating the cavity in an operating tunnel according to claim 7, characterized in that: In step S5, the corrugated steel plates arranged in a ring are constructed symmetrically on both sides and closed at the top.

9. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: In the step S6, the waterproof mortar is epoxy resin mortar.

10. The method for treating the cavity in an operating tunnel according to claim 1, characterized in that: In the step S1, a geological radar is used to detect the three-dimensional size of the tunnel cavity.

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