Method and tool for repairing the joint between a track sleeper and a track bed of a ballastless track bed

Abstract

A method and fixture for repairing gaps between sleepers and ballast in ballastless track beds, belonging to the field of railway engineering maintenance technology, are disclosed. The method includes: determining the gap location and cleaning impurities; installing a special mold to form a sealed cavity, which is then fixed using a wedge-shaped clamping fixture; injecting preheated, low-viscosity repair material under pressure in stages, controlling and maintaining the injection pressure, and adjusting the material temperature using heating wires within the mold to ensure a material penetration depth ≥0.3mm; and removing the mold and inspecting the workpiece after recovering excess material. The repair fixture consists of U-shaped and I-shaped molds connected by spring clips, and includes built-in heating wires, pressure and temperature monitoring instruments. Inflatable airbags or flexible sealing strips are installed at contact points, and the mold frame is made of high-strength composite aluminum alloy. This invention solves the problems of incomplete filling, poor sealing, and low efficiency in traditional repair methods through sealed pressurization, precise temperature control, and material recovery. It offers advantages such as convenient operation, high repair quality, and environmental friendliness and economy, and is suitable for complex gap repairs.

Description

Technical Field

[0001] This invention relates to a repair method and repair tooling, and more particularly to a method and repair tooling for repairing the gap between the sleeper and the track bed in ballastless track bed. Background Technology

[0002] During long-term operation, ballastless track beds may develop gaps between sleepers and the track bed due to factors such as foundation settlement, temperature changes, and train loads. These gaps not only affect the track's geometry and stability but may also further impact the safety and operational quality of the railway line. Traditional repair methods often suffer from low efficiency, difficulty in guaranteeing repair quality, insufficient filling, and a high recurrence rate. Therefore, developing an efficient, precise, and environmentally friendly repair method and tooling is of paramount importance.

[0003] The prior art 1CN116815560A discloses a method for repairing gaps in ballastless tracks, which includes creating multiple grouting holes by drilling holes in a quincunx pattern along the track slab laying direction, avoiding the reinforcing bars, and drilling through the track slab to the surface of the filling layer; sealing the gaps with edge-sealing components and setting multiple vent holes at intervals; inserting grouting pipes into the grouting holes and injecting a flexible cement-based grouting material with mechanical properties similar to the raw materials of the filling layer into the gaps through the grouting pipes in a skip-hole grouting manner; after the flexible cement-based grouting material has hardened, removing the grouting pipes and edge-sealing components; cleaning the grouting holes and injecting a high-strength micro-expansion cement-based material with mechanical properties similar to the track slab into the grouting holes.

[0004] The prior art 2CN107476149B discloses a method for sealing joints in the mortar layer of trenchless track. It determines the sealing grouting area on the track slab sealing layer according to the joint grouting area of ​​the mortar layer, then sets grouting holes and pressure relief holes in the sealing grouting area, and installs an injection tube in each grouting hole. The grouting equipment is used to connect each grouting hole in sequence to complete the grouting, thereby forming a sealing curtain located on the side of the mortar layer.

[0005] The prior art 3CN115748334A discloses a method for grouting repair of vertical reflective cracks in the filling layer of ballastless track, including: drilling horizontally at the cut position of the base plate / support layer when the track slab is covered; cleaning the cut and cavity using a cleaning device connected to a hollow pipe; injecting flexible filling material into the cut and cavity to form flexible filling; drilling overflow holes or grouting holes on the top of the track slab to the vertical reflective crack; installing a pressure grouting head at the position corresponding to the vertical reflective crack, and injecting repair material into the vertical reflective crack through the pressure grouting head until the material overflows and then stopping the injection; replenishing grout through the grouting hole to ensure full injection, and then repairing the overflow hole or grouting hole.

[0006] Existing technology 4CN116005498B discloses a pulsed grouting device for repairing gaps in high-speed railway tracks. This device uses grout as the working medium and utilizes the adhesion effect of the jet in a specific-shaped cavity. The grout flowing out of the outlet has a large diffusion range and high grouting efficiency. When using multi-stage jet superposition, the grout velocity at the jet oscillation outlet is even faster. However, existing technologies 1 and 2 are methods for repairing gaps between the filling layer and the track slab of CRSTI I-type ballastless track. Document 1 uses grouting repair through drilling holes in the track slab, and document 2 uses grouting repair through side sealing. The purpose is to fill the gaps between the layers. The grouting repair material is a repair material with properties matching the mortar layer. These methods cannot repair non-planar gaps and may damage the track structure. Traditional crack and gap repair technologies cannot adapt to irregular sleeper surfaces, easily leading to poor sealing and grout leakage; they also cannot achieve effective pressurization, resulting in incomplete filling of the repair material and insufficient interface penetration.

[0007] Existing technology 3 is used to repair vertical cracks in the filling layer of CRSTI I type slab ballastless track. It mainly involves drilling holes and installing pipes to assist in grouting and filling the side plane. This method cannot be used to repair non-planar cracks.

[0008] The prior art 4 is a planar joint repair tool. This tool cannot adapt to irregular and non-planar joint repair methods, and it is difficult to ensure that the joint can be fully filled. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention discloses a method for repairing the gap between the sleeper and the track bed in ballastless track beds, the technical solution of which is as follows:

[0010] A method for repairing the gap between the sleeper and the ballast bed in a ballastless track bed, characterized by comprising the following steps:

[0011] (1) Determine the repair area: Based on the on-site defect statistics, determine the location and number of gaps between the sleeper and the track bed slab;

[0012] (2) Clean the gaps: Use a powerful vacuum cleaner to clean the impurities and loose materials in the gaps and within a 3-5cm range of the edges;

[0013] (3) Install and fix the mold: Insert the U-shaped mold part from the outside of the sleeper, and connect and fix the I-shaped part to the U-shaped part through spring buckles to form a closed cavity that matches the sleeper and track bed, and use wedge clamping fixture to clamp the mold.

[0014] (4) Pressurized grouting: Open the vent hole and inject the preheated low-viscosity repair material at a pressure of 0.2MPa. After the vent hole overflows, close the vent hole, pressurize to 0.5-0.8MPa and hold the pressure for 2-3 minutes.

[0015] (5) Heating materials: Heating the repair materials inside the mold to 15℃-50℃ according to the ambient temperature, and monitoring the temperature in real time;

[0016] (6) Continuous pressure maintenance: After the pressure is constant, maintain it for 2-3 minutes to ensure that the repair material is fully filled and the penetration depth is ≥0.3mm;

[0017] (7) Recover excess materials: shut down the grouting equipment, purge excess repair materials through the vent holes and filter and recover them;

[0018] (8) Remove the mold and inspect the repair quality after removing the mold and restore the circuit.

[0019] Preferably, the repair material in step (4) is a polymer resin or epoxy resin with a viscosity of ≤150mPa·s at 25°C, a 1d strength of ≥30MPa, a final strength of ≥60MPa, and an adhesive strength of ≥3MPa.

[0020] Preferably, the cavity formed by the mold and the sleeper and track bed in step (3) has a width of 10-15mm and a height of 30-35mm, and the contact part between the mold and the sleeper and track bed is provided with an inflatable airbag or a flexible sealing strip.

[0021] Preferably, in step (4), the grouting pressure is monitored in real time by a pressure monitoring instrument installed in the cavity, and the heating temperature is controlled by a temperature monitoring instrument, with the heating temperature ≤50℃.

[0022] Preferably, the excess repair material recovered in step (7) is filtered through a filter screen and then reused.

[0023] This invention also discloses a tooling for repairing the gap between the sleeper and the ballast bed in ballastless track beds. This tooling is applied to the aforementioned repair method and is characterized by comprising:

[0024] A special mold, consisting of a U-shaped part and an I-shaped part connected and fixed by spring clips, is matched with the shape of the sleeper to form a sealed cavity with a width of 10-15mm and a height of 30-35mm;

[0025] Sealing devices are installed at the contact points between the mold and the sleeper / track bed, including inflatable airbags or flexible sealing strips;

[0026] The wedge-shaped clamping fixture uses a steel rail to provide a reaction force to clamp the mold;

[0027] The inlet and outlet ports and the air inlet and outlet ports are respectively located at the bottom of the U-shaped section and the top of the I-shaped end;

[0028] The heating wire, pressure monitor, and temperature monitor are integrated into the cavity.

[0029] Preferably, the mold frame is made of high-strength composite aluminum alloy material with a strength ≥300MPa and a density of 2.7g / cm³. 3 Its temperature resistance range is -20℃ to 80℃.

[0030] Preferably, the sealing device is made of an elastic material that can adapt to the irregular surfaces of the sleepers and track slabs.

[0031] Preferably, the air inlet is connected to an air blowing device for inflating and expelling excess repair material after grouting.

[0032] Preferably, the heating wire adjusts the temperature of the repair material to 15℃-50℃ according to the ambient temperature, and the temperature is monitored and controlled in real time by a temperature monitoring instrument. Beneficial effects

[0033] (1) The present invention uses a specially designed mold, including a mold body that matches the shape of the gap and is slightly larger in size, an air-filled / flexible sealing strip at the bottom, and a reasonable method of pressurizing and injecting repair material to ensure that the repair material can fill the gap and penetrate into the concrete, thereby enhancing the adhesion to the concrete interface and the concrete strength, and effectively improving the repair quality.

[0034] (2) By setting up a sealed tooling, the present invention prevents the grouting repair material from overflowing, and at the same time enables the recycling of repair material, thus avoiding waste of repair material and achieving environmentally friendly repair.

[0035] (3) The viscosity and curing effect of the repair material are crucial to the repair quality. This invention uses a heating device to heat the mold and precisely controls the heating temperature and time according to the characteristics of the repair material to reduce the viscosity of the repair material, promote its diffusion in the joint and penetration into the concrete, thereby better exerting the performance of the repair material and improving the quality of joint repair.

[0036] (4) The special repair tool of the present invention has a simple structure, the shape of the mold body matches the sleeper and the gap, and the design of each component such as heating device, sealing device, and pressing mechanism is reasonable, making the operation more convenient and efficient. Attached Figure Description

[0037] Figure 1 Flowchart for repairing gaps between sleepers and track slabs;

[0038] Figure 2 : Schematic diagram of the gap between the sleeper and the track slab;

[0039] Figure 3 : Schematic diagram of special mold installation;

[0040] Figure 4 Schematic diagram of constant pressure grouting repair;

[0041] Figure 5 : Schematic diagram of the repair effect;

[0042] Attached figures and their corresponding numbers;

[0043] 1. Rails; 2. Sleepers; 3. Track slabs; 4. Joints; 5. Special molds; 5-1. Skeleton; 5-2. Inflatable airbags or flexible sealing strips; 5-3. Material inlet / outlet; 5-4. Air inlet / outlet; 5-5. Heating belt; 5-6. Pressure monitor; 5-7. Temperature monitor; 5-8. Wedge clamping device; 6. Repair materials. Detailed Implementation

[0044] Traditional crack and gap repair techniques are ill-suited to the irregular surfaces of railway sleepers, often resulting in incomplete sealing and grout leakage. They also fail to achieve effective pressure, leading to insufficient filling of the repair material and inadequate interface penetration. Because railway sleepers are irregularly shaped with varying heights and slopes at their bottom edges, the upper edge of the special mold frame needs to be machined to conform to the sleeper's protruding shape. Due to errors in the sleeper and machining fixtures, a layer of malleable and adaptable material is required between the special mold frame and the sleeper to accommodate any gaps caused by these errors. Furthermore, since the special mold frame's bottom contacts the track slab surface, the uneven height between the top surface of the track slab and the protruding sleeper points, coupled with the track slab's surface irregularity, necessitates the use of malleable and adaptable material at the bottom of the special mold frame to ensure a tight seal between the mold and the track slab. This malleable and adaptable material can be either an inflatable sealant or a flexible sealing material, offering strong adaptability to irregular surfaces.

[0045] Furthermore, traditional low-pressure grouting repair methods are difficult to use for cracks less than 0.2mm wide, requiring prolonged low-pressure penetration (15-20 minutes). This method cannot fully fill small cracks in a short time. However, this method, under relatively high pressure, can fully fill cracks in a short time (3-5 minutes). At the same time, the grouting material can penetrate into the track bed concrete, ensuring full filling while enhancing the bond between the grouting material and the concrete.

[0046] The present invention will be further explained below with reference to specific embodiments.

[0047] During long-term operation, various factors may cause gaps to appear between the sleepers and the cast-in-place ballast slab of ballastless track. These gaps not only affect the structural integrity of the sleepers and ballast slab but may also further impact the stability and safety of the railway line. The construction process for repairing these gaps using low-pressure grouting technology, based on this patented technology, is as follows: Figure 1 As shown, the specific content is as follows:

[0048] A method for repairing the gap between the sleeper and the ballast bed in ballastless track bed, the technical solution of which is as follows:

[0049] (1) Determine the repair area

[0050] Based on the on-site investigation and statistical results of the defects, the location and quantity of the defects 4 of the gap between sleeper 2 and track slab 3 were determined, and the amount of repair materials 6 and the required tools and equipment were reasonably arranged according to the construction characteristics of the track window.

[0051] (2) Clean the seams 4

[0052] Use a powerful vacuum cleaner to clean the impurities and loose materials inside the joint 4 and on the surface of the track bed slab 3 within a 3-5cm range around the edge of the joint 4. This will ensure that the repair material 6 is fully filled and can bond well with the concrete of the track bed slab 3. If the impurities in the joint 4 are not cleaned properly, it may result in incomplete filling of the joint 4 and low or even no adhesion at the interface of the track bed concrete.

[0053] (3) Install and fix the special mold

[0054] First, the U-shaped frame 5-1 of the special mold 5 is inserted around the sleeper 2 from one side of the track outside the sleeper 2. Then, the I-shaped frame 5-1 of the special mold 5 is connected and fixed to the U-shaped frame 5-1 on the other side of the sleeper 2 using spring clips, allowing the mold to be installed / disassembled within 1 minute. The shape of the special mold 5 matches the shape of the sleeper 2, forming a cavity 10-15mm wide and 30-35mm high with the sleeper 2 and the track slab 3. However, the upper part of the special mold 5 that contacts the sleeper 2 is completely aligned with the dimensions of the sleeper 2, while the lower part that contacts the track slab 3 is flat. At the same time, inflatable airbags or flexible sealing strips 5-2 are provided at the contact points with the sleeper 2 and the track slab 3 to ensure a tight fit and form a sealed cavity. Using the reaction force provided by the rail 1, a wedge-shaped clamping device 5-8 is used to clamp the mold, preventing the mold from running during pressurized grouting and causing the repair material 6 to overflow, affecting the joint filling repair effect.

[0055] The special mold frame 5-1 is made of high-strength composite aluminum alloy, which has high strength (≥300MPa), rigidity, and temperature resistance (-20℃~80℃), ensuring the compressive and deformation resistance of a relatively small structure within a certain temperature range; its density is low (2.7g / cm³). 3 This makes the mold lightweight, which is suitable for the lightweight construction requirements of skylight points.

[0056] The special mold 5 has a pre-set inlet / outlet 5-3 at the bottom of the U-shaped section to facilitate the injection of repair material 6 and the recovery of excess material. An air inlet / outlet 5-4 is set at the top of the I-shaped end to facilitate the discharge of gas from the cavity during grouting. After grouting, air is added to flush out excess material. At the same time, a heating band 5-5 is installed in the cavity to heat the repair material 6 when the ambient temperature is low. A pressure monitor 5-6 and a temperature monitor 5-7 are also installed to monitor the grouting pressure and material temperature in the cavity in real time.

[0057] (4) Pressure injection of repair material 6

[0058] Before grouting, open the air inlet / outlet 5-4 and inject preheated low-viscosity repair material 6 (such as polymer resin, epoxy resin, etc.) into the special mold 5 at a pressure of 0.2 MPa through the inlet / outlet 5-3 until grout flows out from the air inlet / outlet 5-4. Close the exhaust valve to form a sealed space. Control the grouting pressure between 0.5 MPa and 0.8 MPa and maintain the pressure for 2 to 3 minutes to ensure that the repair material 6 fills the entire joint 4 and penetrates 0.3 to 1 mm at the concrete interface of the track slab 3 to ensure the adhesion between the grouting repair material 6 and the concrete interface.

[0059] The grouting repair material has a viscosity of less than 150 mPa·s at 625℃, exhibiting excellent fluidity and permeability. Its gelation time is 50–60 min. The viscosity decreases with heating; at 35℃, the viscosity is 100–120 mPa·s with a gelation time of 40–50 min; at 50℃, the viscosity is 50–70 mPa·s with a gelation time of 30–40 min. The viscosity increases at lower temperatures; at 15℃, the viscosity is 170–185 mPa·s with a gelation time of 60–70 min. While ensuring excellent workability, its 1-day strength is greater than 30 MPa, its final strength is greater than 60 MPa, and its bond strength is greater than 3 MPa. It also meets the maintainability requirements during the maintenance window period, ensuring uninterrupted operation after the maintenance window ends.

[0060] (5) Heating materials

[0061] Depending on the site conditions, if the site temperature is low (below 15℃), the repair material 6 should be preheated and insulated offline. Then, heating belts 5-5 should be used online to heat the repair material 6 within the special mold 5. This ensures the material maintains good workability, increases its temperature, reduces its viscosity, promotes filling and penetration into the joint 4, and enhances its adhesion to the concrete. However, the heating temperature must not exceed 50℃; excessively high temperatures will cause the material to react too quickly, resulting in insufficient working time or the inability to recover excess material. The heating temperature and time must be precisely controlled based on the characteristics of the repair material 6.

[0062] (6) Continuous pressure maintenance

[0063] After the pressure inside the cavity is kept constant by injecting the repair material 6, a certain pressure is maintained for 2-3 hours, and the filling fullness of the gap 6 reaches 100%. At the same time, the repair material 6 is allowed to penetrate well into the concrete, with a penetration depth of more than 0.2mm.

[0064] (7) Recycle excess repair materials

[0065] After the pressure holding period, turn off the grouting machine, connect the receiving pipe to the inlet / outlet 5-3, and simultaneously inflate through the air inlet / outlet 5-4 to discharge and recycle excess grouting repair material 6. A filter screen is installed in the recycling device to filter out particulate impurities for later use.

[0066] (8) Remove the mold and restore the circuit.

[0067] After the materials are collected, the special mold 5 is removed, and the condition of the gap 4 after grouting is visually inspected to ensure that the repair quality meets the requirements and the line is restored.

[0068] This invention also discloses a tooling for repairing the gap between the sleeper and the ballast bed in ballastless track, comprising:

[0069] The special mold 5 is made of high-strength composite aluminum alloy and includes a U-shaped frame 5-1 and an I-shaped frame 5-1. The U-shaped frame 5-1 is inserted into the sleeper 2 from one side of the track. The I-shaped frame 5-1 and the U-shaped frame 5-1 are connected and fixed to the sleeper 2 on the other side by snap-fit. The shape of the special mold 5 matches the shape of the sleeper 2, forming a cavity 10-15mm wide and 30-35mm high with the sleeper 2 and the track bed slab 3. The upper part of the special mold 5 contacts the sleeper 2. The dimensions are perfectly matched, and the lower part is flat in contact with the track bed slab 3. Inflatable airbags or flexible sealing strips 5-2 are provided at the contact points with the sleepers 2 and the track bed slab 3. Material inlet and outlet ports 5-3 are preset at the bottom of the U-shaped section, and air inlet and outlet ports 5-4 are set at the top of the I-shaped end. Heating belts 5-5, pressure monitors 5-6 and temperature monitors 5-7 are provided in the cavity. The sealing device is made of elastic material and is used to seal and reinforce the special mold 5. The wedge-shaped clamping device 5-8 uses the reaction force provided by the rail 1 to clamp the mold.

[0070] The cavity size is determined based on the characteristics of the track maintenance period, which requires time-saving in each process. Therefore, the cavity size must be controlled to minimize grouting time, heating time, and material recovery time; thus, a smaller cavity volume is better. Because the cavity will house the heating belt 5-5, the pressure monitoring instrument 5-6 receiver, and the temperature monitoring instrument 5-7 receiver, the cavity width is 10-15mm. The cavity height is based on the ballastless track structure design drawing, with the protruding edge of the sleeper 2 30mm from the top surface of the track slab 3.

[0071] The inlet / outlet 5-3 of the special mold 5 is used for injecting the repair material 6 and recovering excess material. The air inlet / outlet 5-4 is used for venting gas from the cavity during grouting and for adding air to flush out excess material after grouting. The heating belt 5-5 is used to heat the material when the ambient temperature is low. The pressure monitor 5-6 and temperature monitor 5-7 are used to monitor the grouting pressure and material temperature in the cavity in real time.

[0072] The present invention aims to provide a method and special repair tool for repairing the gap 4 between the sleeper 2 and the track slab 3 of ballastless track bed. The method can repair the gap 4 between the sleeper 2 and the track slab 3 efficiently and accurately, while ensuring the full utilization of the repair material 6, thereby improving the repair quality and efficiency.

[0073] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A method for repairing the gap between the sleeper and the ballast bed in a ballastless track bed, characterized in that, Includes the following steps: (1) Determine the repair area: Based on the on-site defect statistics, determine the location and number of gaps between the sleeper and the track bed slab; (2) Clean the gaps: Use a powerful vacuum cleaner to clean the impurities and loose materials in the gaps and within a 3-5cm range of the edges; (3) Install and fix the mold: Insert the U-shaped mold part from the outside of the sleeper, and connect and fix the I-shaped part to the U-shaped part through spring buckles to form a closed cavity that matches the sleeper and track bed, and use wedge clamping fixture to clamp the mold. (4) Pressurized grouting: Open the vent hole and inject the preheated low-viscosity repair material at a pressure of 0.2MPa. After the vent hole overflows, close the vent hole, pressurize to 0.5-0.8MPa and hold the pressure for 2-3 minutes. (5) Heating materials: Heating the repair materials inside the mold to 15℃-50℃ according to the ambient temperature, and monitoring the temperature in real time; (6) Continuous pressure maintenance: After the pressure is constant, maintain it for 2-3 minutes to ensure that the repair material is fully filled and the penetration depth is ≥0.3mm; (7) Recover excess materials: shut down the grouting equipment, purge excess repair materials through the vent holes and filter and recover them; (8) Remove the mold and inspect the repair quality after removing the mold and restore the circuit.

2. The repair method according to claim 1, characterized in that, In step (4), the repair material is a polymer resin or epoxy resin with a viscosity of ≤150 mPa·s at 25℃, a 1-day strength of ≥30 MPa, a final strength of ≥60 MPa, and an adhesive strength of ≥3 MPa.

3. The repair method according to claim 1, characterized in that, In step (3), the cavity formed by the mold, sleeper, and track bed has a width of 10-15mm and a height of 30-35mm, and the contact area between the mold and the sleeper and track bed is provided with an inflatable airbag or a flexible sealing strip.

4. The repair method according to claim 1, characterized in that, In step (4), the grouting pressure is monitored in real time by a pressure monitoring instrument installed in the cavity, and the heating temperature is controlled by a temperature monitoring instrument, with the heating temperature ≤50℃.

5. The repair method according to claim 1, characterized in that, The excess repair material recovered in step (7) is filtered through a filter screen and reused.

6. A repair fixture for repairing the gap between the sleeper and the ballast bed in ballastless track, wherein the fixture is applied to the repair method described in claim 1, characterized in that, include: The special mold consists of a U-shaped part and an I-shaped part connected and fixed by spring clips. The mold matches the shape of the sleeper to form a sealed cavity with a width of 10-15mm and a height of 30-35mm. Sealing devices are installed at the contact points between the mold and the sleeper / track bed, including inflatable airbags or flexible sealing strips; The wedge-shaped clamping fixture uses a steel rail to provide a reaction force to clamp the mold; The inlet and outlet ports and the air inlet and outlet ports are respectively located at the bottom of the U-shaped section and the top of the I-shaped end; The heating wire, pressure monitor, and temperature monitor are integrated into the cavity.

7. The repair fixture according to claim 6, characterized in that, The mold frame is made of high-strength composite aluminum alloy with a strength ≥300MPa and a density of 2.7g / cm³. 3 Its temperature resistance range is -20℃ to 80℃.

8. The repair fixture according to claim 6, characterized in that, The sealing device is made of elastic material and can adapt to the irregular surfaces of sleepers and track slabs.

9. The repair fixture according to claim 6, characterized in that, The air inlet is connected to an air blowing device, which is used to inflate and expel excess repair material after grouting.

10. The repair fixture according to claim 6, characterized in that, The heating wire adjusts the temperature of the repair material to 15℃-50℃ according to the ambient temperature, and the temperature is monitored and controlled in real time by a temperature monitoring instrument.

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