High-speed railway ballastless track expansion joint bed damage repairing method

Abstract

The present application belongs to the technical field of maintenance of high-speed railway ballastless track structure, and particularly relates to a method for repairing damage of expansion joint bed of high-speed railway ballastless track. The technical scheme is as follows: a method for repairing damage of expansion joint bed of high-speed railway ballastless track, comprising the following steps: S1: determining expansion joint structure design through finite element design calculation; S2: removing damaged part of expansion joint; S3: treating interface after removing damaged part of expansion joint; S4: placing expansion joint material according to expansion joint structure design of step S1; S5: pouring repair mortar in bridge section base area; S6: setting isolation layer on surface of bridge section base repair area; S7: pouring repair mortar in track bed area; S8: closing expansion joint caulking; and S9: closing surface of repair area. The present application provides a method for repairing damage of expansion joint bed of high-speed railway ballastless track.

Description

A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track. Technical Field

[0001] This invention belongs to the field of maintenance and upkeep technology for ballastless track structures in high-speed railways, and specifically relates to a method for repairing damage to the track bed of expansion joints in transition sections of ballastless track in high-speed railways. Background Technology

[0002] Double-block ballastless track structures are widely used in my country, where the track slab and base slab are separated at the expansion joint. However, existing projects often suffer from defects such as the absence of expansion joints, the use of dummy joints, or the connection of the transition section base slabs due to construction errors. Under temperature loads, tensile stress concentration occurs at the junction of the actual dummy joint and the actual base slab in the transition section of the ballastless track structure in road and bridge construction, causing cracking and damage at the expansion joint. There is an urgent need to develop a repair technique to restore structural function. Currently, repair techniques for expansion joints in high-speed railway ballastless tracks are limited to material replacement and repair, lacking techniques and methods for treating dummy joints and cracks in the track slab structure at expansion joints. Current ballastless track crack repair techniques mainly include the following:

[0003] Adhesive injection repair method: This method involves injecting a special adhesive to fill cracks, thereby improving the structural strength at the cracks. It has advantages such as ease of operation and significant results. Various types of adhesives are available, including inorganic and organic types. Inorganic adhesives mainly include water glass two-component materials and cement-based materials, while organic adhesives include epoxy resin, epoxy mortar, silicone-based materials, polysulfide-based materials, and polyurethane-based materials. It is important to pay attention to the durability and environmental friendliness of the adhesive. For cracks at expansion joints, the flexibility and adhesion of the repair material are also crucial, requiring high-performance materials.

[0004] Prestressed repair method: Prestressed steel bars or carbon fiber cloth are installed at the cracks to apply a certain amount of prestress and reduce crack expansion. This method is suitable for situations where there are many cracks and they are widely distributed. It requires professional structural design and construction process design, and the repaired cracks are rigid and do not have the ability to deform.

[0005] Steel plate reinforcement method: Steel plates are pasted or implanted at the crack to improve the structural strength at the crack. This method has the advantages of significant reinforcement effect and short construction period, but the repaired crack structure does not have the ability to deform, and the crack itself is not reinforced, the structural stress that caused the cracking is not resolved, and the function of the expansion joint is not restored.

[0006] In summary, existing methods for repairing track bed damage at expansion joints in ballastless tracks have the following drawbacks:

[0007] 1. Methods such as replacing or repairing expansion joint materials cannot solve problems such as false joints and structural cracking.

[0008] 2. After repair, the cracks lack flexibility, and the expansion joint cannot restore its function or release structural stress.

[0009] 3. The base plate of the roadbed section extends into the bridge section without an isolation layer, and the existing repair methods cannot solve this problem. Summary of the Invention

[0010] In order to solve the above-mentioned problems in the existing technology, the purpose of this invention is to provide a method for repairing the damaged track bed of the expansion joint of the ballastless track in high-speed railway, which can supplement the expansion joint structure of the ballastless track structure and repair the problem of longitudinal jointing of the bottom plate.

[0011] The technical solution adopted in this invention is as follows:

[0012] A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track includes the following steps:

[0013] S1: Determine the structural design of the expansion joint through finite element design calculations;

[0014] S2: Remove the damaged parts of the expansion joint;

[0015] S3: Processing the interface after chiseling away the damaged part of the expansion joint:

[0016] S4: Place the expansion joint material according to the expansion joint structure design in step S1;

[0017] S5: Pour repair mortar in the base area of ​​the bridge section;

[0018] S6: Install an isolation layer on the surface of the bridge base repair area;

[0019] S7: Pour repair mortar in the track bed area;

[0020] S8: Sealing expansion joints;

[0021] S9: Sealing and repairing the surface of the area.

[0022] This invention involves chiseling away the damaged area of ​​the expansion joint in a bridge section, then pouring repair mortar into the base area and the track bed area to fundamentally reinforce the cracks, eliminate the structural stress that causes cracking, and solve problems such as false joints and structural cracking.

[0023] This invention repairs the base area and track bed area of ​​a bridge section. Before repair, expansion joint material is placed in a certain area, so that the expansion joint is retained after repair, the track structures on both sides are completely separated, the function of the expansion joint can be restored, and the structure can release stress through the expansion joint.

[0024] The present invention sets an isolation layer between the base repair area and the track bed repair area, which can balance the transition section base plate and release stress after repair.

[0025] As a preferred embodiment of the present invention, in step S1, when determining the expansion joint structure design, specific parameters including the area to be removed, the amount of rebar to be installed, and the performance of the repair material are determined. Finite element design calculations are performed using finite element software.

[0026] As a preferred embodiment of the present invention, step S3 specifically includes the following steps:

[0027] When cleaning and removing damaged areas of expansion joints, roughen the hardened surfaces by chiseling.

[0028] Treat exposed rebar;

[0029] Based on the amount of rebar required by the finite element design, ribbed steel bars are implanted at the interface.

[0030] Apply the interface agent evenly to the exposed surface.

[0031] As a preferred embodiment of the present invention, in step S4, the expansion joint material is one of the following: precast foam board, cast-in-place polyurethane material, or silicone grouting material.

[0032] As a preferred embodiment of the present invention, step S5 specifically involves: erecting a template according to the design dimensions of the ballastless track, applying a release agent to the inner surface of the template; filling the repaired area of ​​the base with repair mortar, ensuring the poured surface is flush with the original base surface; and promptly removing the template after the repair mortar has fully set, followed by covering and water curing. The repair mortar includes, but is not limited to, cement mortar, epoxy mortar, green low-carbon composite cement mortar, alkali-activated oligomer mortar, etc., provided the repair material reaches its design strength.

[0033] As a preferred embodiment of the present invention, step S6 specifically involves placing the isolation material on the surface of the bridge section base repair area in step S5. The isolation material is one of geotextile, composite fiber cloth, or polyethylene film, restoring the design function of the isolation layer.

[0034] As a preferred embodiment of the present invention, step S7 specifically involves: erecting a template according to the design dimensions of the ballastless track, applying a release agent to the inner surface of the template; filling the repaired portion of the track bed with repair mortar, ensuring the poured surface is flush with the original track bed surface; and promptly removing the template after the repair mortar has fully set, followed by covering and water curing. Repair mortar includes, but is not limited to, cement mortar, epoxy mortar, green low-carbon composite cement mortar, and alkali-activated oligomer mortar.

[0035] As a preferred embodiment of the present invention, step S8 specifically involves: cleaning a certain area of ​​the expansion joint surface, and then evenly applying sealant to the expansion joint surface. The sealant material includes one of silicone, polysulfide, and polyurethane. To ensure an aesthetically pleasing appearance, adhesive tape can be pasted on the outside of the application area, and the tape should be cleaned off after construction is completed.

[0036] In a preferred embodiment of the present invention, step S9 specifically involves: grinding and cleaning the repair area and a certain surrounding area; preparing a surface sealing material according to the required proportions; and applying the surface sealing material evenly to the repair area multiple times. The sealing material includes one of silicone, polysulfide, or polyurethane. Applying the material evenly to the repair area multiple times prevents moisture from entering the repair interface.

[0037] As a preferred embodiment of the present invention, after step S9, the following steps are performed:

[0038] S10: Site cleanup: After the day's work is completed, conduct a comprehensive search of the work area to prevent tools and materials from being left behind, and promptly and properly dispose of construction waste and debris generated during the construction process, bagging and removing them from the site.

[0039] The beneficial effects of this invention are as follows:

[0040] 1. This invention involves chiseling away the damaged areas of a bridge section, then pouring repair mortar into the base area and the track bed area to fundamentally reinforce the cracks, eliminate the structural stress that causes cracking, and solve problems such as false cracks and structural cracking.

[0041] 2. This invention repairs the base area and track bed area of ​​a bridge section. Before repair, expansion joint material is placed in a certain area, so that the expansion joint is retained after repair, the track structures on both sides are completely separated, the function of the expansion joint can be restored, and the structure can release stress through the expansion joint.

[0042] 3. The present invention sets an isolation layer between the base repair area and the track bed repair area, which can restore the structural design function and release stress and deformation after repair. Attached Figure Description

[0043] Figure 1 is a method diagram of the present invention;

[0044] Figure 2 is a schematic diagram of the construction structure of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the invention can be combined with each other.

[0047] As shown in Figure 1, the method for repairing damaged track bed at expansion joints in high-speed railway transition sections according to this embodiment includes the following steps:

[0048] S1: Finite element software calculation. Using one of the finite element software programs, determine the structural design of the expansion joint, including parameters such as the area to be removed, the amount of rebar to be installed, and the performance of the repair materials.

[0049] S2: Remove damaged sections of the expansion joint:

[0050] Use one or more of the following mechanical tools in combination: electric hammer, hand hammer, etc., to completely remove the damaged area of ​​the expansion joint, down to the designed removal area. Also use a hand hammer and chisel to remove and clean up any loose particles at the interface.

[0051] S3: Interface Processing

[0052] Roughen the hardened surface after processing, and clean the interface using cleaning tools such as a hair dryer, brush, and industrial vacuum cleaner. Treat the exposed rebar, including one of the following steps: rust removal and grinding, removal of severely rusted rebar, or rebar re-insertion; insert φ8 ribbed rebars at the interface, and determine the amount of rebar to be inserted using finite element software, with a rebar spacing of 8-10cm and an exposed length such that the protective layer thickness is greater than 3cm; use a brush to evenly apply an interface agent to the exposed interface.

[0053] S4: Set expansion joints:

[0054] Place and secure the expansion joint material at the designed location. The material can be one of the following: precast foam board, cast-in-place polyurethane material, or silicone grouting material. The size of the expansion joint should ideally completely separate the track structures on both sides, restoring the function of the expansion joint.

[0055] S5: Pour repair mortar into the base area:

[0056] Erect formwork according to the design dimensions of the ballastless track, and apply a release agent to the inner surface of the formwork. Fill the repaired area densely with repair materials, including but not limited to cement mortar, epoxy mortar, green low-carbon composite cement mortar, and alkali-activated oligomer mortar, until the repair materials reach the design strength. The poured surface should be flush with the original base surface. After the repair mortar has fully set, remove the formwork promptly and cover and cure with water.

[0057] S6: Set an isolation layer:

[0058] Cut the appropriate size of the isolation material, place it on the surface of the repair area of ​​the bridge section base, and fix it firmly. The isolation material is one of geotextile, composite fiber cloth, or polyethylene film, restoring the design function of the isolation layer.

[0059] S7: Pouring repair mortar in the track slab area:

[0060] Erect formwork according to the design dimensions of the ballastless track, and apply release agent to the inner surface of the formwork; fill the repair area with repair materials, including but not limited to cement mortar, epoxy mortar, green low-carbon composite cement mortar, alkali-activated oligomer mortar, etc. When the repair materials reach the design strength, the pouring surface should be flush with the original track bed surface; remove the formwork in time after the repair mortar has finally set, and cover and water for curing.

[0061] S8: Expansion joint sealing:

[0062] Clean the surface of the expansion joint thoroughly, then apply sealant evenly. Sealant materials include silicone, polysulfide, and polyurethane. To ensure a neat appearance, you can apply adhesive tape to the outside of the applied area. Clean the tape off after application.

[0063] S9: Surface sealing of the repaired area:

[0064] Grind and clean the repair area and a certain area around it. Prepare the surface sealing material strictly according to the mixing ratio requirements. The sealing material includes one of silicone, polysulfide, and polyurethane. Apply the material evenly to the repair area multiple times to prevent moisture from entering the repair interface.

[0065] S10: On-site cleanup:

[0066] After the day's work is completed, a comprehensive search of the work area is conducted to prevent tools and materials from being left behind. Construction waste and debris generated during the construction process are promptly and properly disposed of, and bagged and taken out of the site.

[0067] This invention involves chiseling away the damaged areas of a bridge section and then pouring repair mortar into the base area and the track bed area to fundamentally reinforce the cracks, eliminate the structural stress that causes cracking, and solve problems such as false cracks and structural cracking.

[0068] This invention repairs the base area and track bed area of ​​a bridge section. Before repair, expansion joint material is placed in a certain area, so that the expansion joint is retained after repair, the track structures on both sides are completely separated, the function of the expansion joint can be restored, and the structure can release stress through the expansion joint.

[0069] The present invention sets an isolation layer between the base repair area and the track bed repair area, which can restore the structural design function and release stress and deformation after repair.

[0070] This invention is not limited to the above-described optional embodiments. Anyone can derive other various forms of products under the guidance of this invention. However, regardless of any changes made in their shape or structure, any technical solution that falls within the scope of the claims of this invention shall be protected by this invention.

Claims

1. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track, characterized in that: Includes the following steps: S1: Determine the structural design of the expansion joint through finite element design calculations; S2: Remove the damaged parts of the expansion joint; S3: Process the interface after chiseling away the damaged part of the expansion joint; S4: Place the expansion joint material according to the expansion joint structure design in step S1; S5: Pour repair mortar in the base area of ​​the bridge section; S6: Install an isolation layer on the surface of the bridge base repair area; S7: Pour repair mortar in the track bed area; S8: Sealing expansion joints; S9: Sealing and repairing the surface of the area.

2. The method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: In step S1, when determining the structure design of the expansion joint, specific parameters are determined, including the area to be removed, the amount of rebar to be installed, and the performance of the repair material.

3. The method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S3 specifically includes the following steps: roughening the hard surface when cleaning and chiseling the damaged parts of the expansion joint; removing rust from the exposed steel bars; inserting ribbed steel bars at the interface according to the amount of steel bars calculated by finite element design; and uniformly applying an interface agent to the exposed interface.

4. The method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: In step S4, the expansion joint material is one of the following: precast foam board, cast-in-place polyurethane material, or silicone grouting material.

5. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S5 is as follows: Erect the formwork according to the design dimensions of the ballastless track, and apply a release agent to the inner surface of the formwork; use repair mortar to fill the repaired part of the base tightly, and the pouring surface should be flush with the original base surface; remove the formwork in time after the repair mortar has finally set, and cover and spray water for curing.

6. The method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S6 specifically involves placing the isolation material on the surface of the bridge section base repair area in step S5.

7. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S7 is as follows: Erect formwork according to the design dimensions of ballastless track, and apply release agent to the inner surface of the formwork; use repair mortar to fill the repaired part of the track bed densely, and the pouring surface should be flush with the original track bed surface; remove the formwork in time after the repair mortar has finally set, and cover and water for curing.

8. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S8 specifically involves cleaning a certain area of ​​the expansion joint surface and applying sealant evenly to the expansion joint surface.

9. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to claim 1, characterized in that: Step S9 specifically involves: grinding and cleaning the repair area and a certain area around it, preparing the surface sealing material according to the mixing ratio requirements, and applying the surface sealing material evenly to the repair area multiple times.

10. A method for repairing damaged track bed at expansion joints in high-speed railway ballastless track according to any one of claims 1 to 9, characterized in that: After step S9, proceed with the following steps: S10: Site cleanup: After the day's work is completed, conduct a comprehensive search of the work area to prevent tools and materials from being left behind, and promptly and properly dispose of construction waste and debris generated during the construction process, bagging and removing them.

Images