Ballastless track system and macromolecule elastic composite material removing and replacing method thereof

Abstract

The invention discloses a ballastless track system and a macromolecule elastic composite material removing and replacing method thereof, and relates to the technical field of urban rail transit construction.The system comprises a rail bearing groove, a steel rail and a macromolecule elastic composite material, and a layer of PTEF teflon glass fiber composite bonding belt is further laid at the bottom of the rail bearing groove; and the bonding surface of the bonding belt is bonded with the groove bottom of the rail bearing groove. The method comprises the following steps: S1, confirming to clear a replacement section; s2, an integral cutting process; s3, cleaning work; s4, carrying out drying treatment; s5, treatment before pouring is conducted, specifically, a layer of PTEF Teflon glass fiber composite bonding belt is laid at the bottom of the rail bearing groove, the bonding belt is made to be completely attached to the interface of the bottom of the rail bearing groove, and the side wall of the rail bearing groove is coated with a layer of macromolecule elastic composite material bonding agent; s6, accurately positioning the steel rail; and S7, overall pouring is conducted. According to the method, the whole structure of the high-molecular elastic composite material coated steel rail can be easily taken out, so that the removal and replacement operations are more convenient, and the requirements of short outage period and rapid construction of urban rail transit can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of urban rail transit construction, and in particular to a ballastless track system using an elastic composite material to replace traditional spring fasteners and a method for quickly removing and replacing the elastic composite material. Background Art

[0002] At present, with the development needs of urban transportation and the increasing population, the rail transit industry in large and medium-sized cities is accelerating its development. The usage frequency of public transportation shows an obvious increasing trend. In particular, the rail transit industry in relatively developed cities is facing huge pressure. Therefore, the operation and maintenance of rail transit have become the key points and difficulties in the development of urban rail transit construction technology.

[0003] In rail construction projects, some polymer elastic composite materials for embedded continuous support ballastless track systems have emerged. The polymer elastic composite material is poured into the rail support groove and wrapped around the track to form a wrapped structure to replace traditional fasteners, playing the role of continuously supporting and fixing the rail.

[0004] During the normal service of the track, with the irregular vibration and frequent stress of the track, the polymer elastic composite material used to wrap the rail will face problems such as damage, reduced elasticity or failure, and local crushing, which may even directly lead to the failure of the rail vibration reduction stress mode. Therefore, manual removal and replacement operations of the material are required. However, due to the strong adhesion between the polymer elastic composite material and the concrete of the rail support groove, the two sides of the rail support groove can be cut off by a cutting machine, but the operation of the bottom of the rail support groove is more difficult. Moreover, due to the particularity of the operation time and the high frequency of use of urban rail transit, if problems occur, they must be quickly removed and replaced within a short time, and at the same time, the normal train operation requirements for the next day must be ensured. Therefore, it is very necessary to invent an efficient and rapid removal and replacement method for the polymer elastic composite material suitable for the ballastless track system.

[0005] The invention patent application with the publication number CN111663375A discloses a new type of beam-type embedded track system and its construction and maintenance process. The patent has the following deficiencies: The adjustment gasket structure used in it needs to be placed at multiple points when replacing a longer unit. Since the requirements of vibration reduction and noise reduction need to be met during train operation, the rail must generate a displacement of 1-2 mm during train operation. As the number of rail adjustment gaskets increases, the sinking displacement of the rail will be restricted by the gaskets, thereby reducing the sinking displacement of the rail, weakening the vibration reduction and noise reduction effect. The displacement amount decreases, and at the same time, there will also be a problem of inconsistent deformation between the gasket and the filling material. Moreover, in the removal process of this method, there will still be three cutting surfaces on the two sides and the bottom of the rail support groove, which reduces the construction efficiency and increases the construction period, and does not have the ability of fast construction. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a ballastless track system and a method for removing and replacing a polymer elastic composite material, so as to solve the technical problems of difficult removal and replacement operations of the polymer elastic composite material, slow construction speed, and long construction period existing in the prior art.

[0007] The technical solution for solving the above technical problem is: a ballastless track system, including a rail support groove, a rail, and a polymer elastic composite material. A layer of PTEF Teflon fiberglass composite adhesive tape is also laid on the bottom of the rail support groove. The adhesive surface of the adhesive tape is bonded to the bottom of the rail support groove, and the non-adhesive surface of the adhesive tape is in contact with the polymer elastic composite material.

[0008] Another technical solution of the present invention is a method for removing and replacing a polymer elastic composite material of a ballastless track system, including the following steps: S1. Confirm the removal and replacement section; S2. Overall cutting process: In the removal and replacement section, use a cutting machine to remove the polymer elastic composite material along the side wall of the rail support groove, and take out the overall structure of the polymer elastic composite material covering the rail; S3. Cleaning work: Use a cleaning solvent to completely clean the polymer elastic composite material on the inner wall of the rail support groove and the outer surface of the rail until there is no bonding phenomenon or attached particles in the rail support groove and on the surface of the rail, and place the rail outside the rail support groove to ensure that the rail is not re-polluted; S4. Drying treatment: Use a blower to dry the inner wall of the rail support groove and the outside of the rail until there is no obvious water mark or bonding particles on the inner wall of the rail support groove and the surface of the rail, which is regarded as the completion of the drying treatment; S5. Pretreatment before pouring: Lay a layer of PTEF Teflon fiberglass composite adhesive tape on the bottom of the rail support groove, so that the adhesive surface of the adhesive tape completely adheres to the bottom interface of the rail support groove, and apply a layer of polymer elastic composite material adhesive on the side wall of the rail support groove; S6. Precise positioning of the rail: Based on the center line of the line, adjust the position of the rail in the rail support groove to ensure that the geometric shape of the gauge line meets the line requirements; when the position of the rail is adjusted, use a fixed restraint element to restrain and fix the position of the rail; S7. Overall pouring: Use a pouring device to pour the polymer elastic composite material into the rail support groove in the removal and replacement section as a whole, and ensure that the poured material is completely bonded to other sections.

[0009] A further technical solution of the present invention is that when the ballastless track is initially laid, before initially pouring the polymer elastic composite material, it is necessary to lay a layer of PTEF Teflon fiberglass composite adhesive tape on the bottom of the rail support groove in the section to be poured as a whole.

[0010] A further technical solution of the present invention is that the PTEF Teflon fiberglass composite bonding tape should meet the requirements of the national standard GB / T39714.1-2020 "Plastics - Polytetrafluoroethylene (PTFE) Semi-finished Products". To ensure that the bonding tape completely covers the entire bottom cross-section of the track bed groove during the overall structure removal process in the cutting process, and there should be no bonding on the groove wall.

[0011] A further technical solution of the present invention is that the cutting machine used in step S2 should meet the requirements of the national standards GB / T38196-2019 "Safety Requirements for Construction Machinery and Equipment - Floor Cutting Machines" and GB13960.11-2000 "Safety of Movable Electric Tools - Part 2: Particular Requirements for Profile Cutting Machines". The cutting gear material is selected as ultra-high molecular weight polyethylene or nylon material.

[0012] A further technical solution of the present invention is that the cleaning solvent used in the cleaning work in step S3 is an organic solvent prepared by mixing acetone CH3COCH3 and ethanol CH3CH2OH in a mass ratio of 4:1.

[0013] A further technical solution of the present invention is that the high molecular elastic composite adhesive in step S5 is a silane coupling agent prepared by mixing two components of γ-glycidoxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a mass ratio of 2:1.

[0014] A further technical solution of the present invention is that the method of using fixed restraint elements to restrain and fix the position of the rail in step S6 is the two-way restraint method. Multiple finished high molecular elastic composite pads are used to support the bottom of the rail to control the vertical height of the track, and two finished high molecular elastic composite products are synchronously arranged at the rail waist to laterally fix the accurate position of the rail in the track bed groove.

[0015] Due to the adoption of the above structure, compared with the prior art, a ballastless track system of the present invention and its method for removing and replacing high molecular elastic composite materials have the following beneficial effects: 1. The removal and replacement operations of materials are convenient In the ballastless track system of the present invention, a layer of PTEF Teflon fiberglass composite bonding tape is also laid on the bottom of the track bed groove. The bonding surface of the bonding tape is bonded to the bottom of the track bed groove, and the non-adhesive surface of the bonding tape is in contact with the high molecular elastic composite material. When removing and replacing the elastic composite material in this ballastless track system, due to the setting of the bonding tape, the bonding between the high molecular elastic composite material and the bottom concrete of the track bed groove can be effectively isolated. After cutting off the high molecular elastic composite material on the side wall of the track bed groove, the overall structure of the high molecular elastic composite material covering the rail can be easily taken out, making the removal and replacement operations more convenient.

[0016] 2. Fast construction speed and short construction period The PTEF Teflon fiberglass composite bonding tape laid at the bottom of the track bed groove in the present invention can reduce the bonding surface between the poured material and the track bed groove, featuring a simple and fast method, with fast construction speed and short construction period, and can meet the requirements of short outage period and rapid construction required by urban rail transit.

[0017] 3. Can ensure that the material continuously provides the mechanical support requirements for train operation on the track Since the high molecular elastic composite material of the present invention is in a three-phase constraint state on two sides and one bottom surface in the track bed groove, the mechanical properties of the high molecular elastic composite material will not be affected by the arrangement of the bonding tape, and it can still ensure that the material continuously provides the mechanical support requirements for train operation on the track.

[0018] 4. Can accurately and quickly adjust the positioning of the rail in the track bed groove When positioning the rail in the present invention, the center line of the line is used as the reference to adjust the position of the rail in the track bed groove to ensure that the geometric profile of the gauge line meets the line requirements; after the position of the rail is adjusted, fixed constraint elements are used to constrain and fix the position of the rail. Therefore, the present invention can accurately and quickly adjust the positioning of the rail in the track bed groove and ensure the continuity of the track after construction.

[0019] 5. Can be constructed in sections The present invention can be constructed in sections and can quickly remove and replace the damaged section of the ballastless track system according to accurate positioning.

[0020] 6. Can avoid rejection Since the rail adjustment component used in the present invention is a cured product of the same material in the track bed groove, it can ensure the deformation coordination ability of the material. At the same time, due to the mutual bonding of the same material, rejection will not occur, avoiding the problems in the prior art that the rail settlement displacement decreases due to train operation load and requirements, and there is also a problem of inconsistent deformation between the gasket and the filler.

[0021] Next, in combination with the drawings and specific embodiments, the technical features of a ballastless track system and its method for removing and replacing the high molecular elastic composite material of the present invention will be further described. Description of the Drawings

[0022] Figures 1 - 3 : Schematic structural diagram of a ballastless track system of the present invention described in Embodiment 1, where: Figure 1 : Front view cross-sectional view, Figure 2 : Figure 1 A-A cross-sectional view of Figure 3 :Figure 1 Top view; Description of the drawings: 1 - Rail support groove, 2 - Rail, 3 - High molecular elastic composite material, 4 - PTEF Teflon fiberglass composite bonding tape. Detailed implementation manners Embodiment 1

[0023] As Figures 1 to 3 shown, a ballastless track system includes a rail support groove 1, a rail 2, and a high molecular elastic composite material 3. A layer of PTEF Teflon fiberglass composite bonding tape 4 is also laid on the bottom of the rail support groove. The bonding surface of the PTEF Teflon fiberglass composite bonding tape 4 is bonded to the bottom of the rail support groove, and the non - sticky surface of the bonding tape is in contact with the high molecular elastic composite material. Among them, Figure 1 is a cross - section along the length direction of the track system, Figure 2 is a cross - section along the width direction of the track system; the PTEF Teflon fiberglass composite bonding tape is a high - temperature - resistant tape made by using fiberglass as the base fabric, coating with Teflon emulsion, drying to form Teflon fiberglass cloth, and then secondarily coating with silicone adhesive.

[0024] The described rail support groove 1 belongs to a simplified structure. It can be a precast part or a cast - in - place part. Its main function is to place the rail and provide the coating function for the high molecular elastic composite material. The rail support groove 1 is connected to the base or the support layer of the ballastless track through a high - performance asphalt mortar or a self - compacting concrete layer to provide elastic support and load transfer. And the inside of the rail support groove 1 is a square structure, which has the advantages of convenient cleaning and replacement.

[0025] The types of the described rail 2 are diverse. Classified by mass per meter, there are rails of 43 kg / m, 50 kg / m, and 60 kg / m. Classified by shape, it can be specifically divided into flat - bottom rails and channel rails.

[0026] The described high molecular elastic composite material 3 is a prior art and can be composed of polysulfide rubber or single - and double - component polyurethane prepolymers combined with thickeners, toughening agents, accelerators, defoaming agents, etc. Embodiment 2

[0027] A method for removing and replacing the high molecular elastic composite material of the ballastless track system described in Embodiment 1 includes the following steps: S1. Confirm the section for removal and replacement: Confirm the section of the removal and replacement section according to the "Measures for the Operation, Maintenance and Management of Urban Rail Transit Facilities and Equipment", "Technical Specification for Monitoring of Urban Rail Transit Engineering" (GB 50911 - 2013), and the replacement requirements of the high molecular elastic composite material for rail transit.

[0028] S2. Removal process: In the replacement section to be removed, use a cutting machine to remove the polymer elastic composite material along the side wall of the track bed groove, and take out the overall structure of the polymer elastic composite material covering the rail; S3. Cleaning work: Use a cleaning solvent to completely clean the polymer elastic composite material on the inner wall of the track bed groove and the outer surface of the rail until there is no bonding phenomenon or attached particles in the track bed groove and on the rail surface, and place the rail outside the track bed groove to ensure that the rail is not re - contaminated; S4. Drying treatment: Use a blower to dry the inner wall of the track bed groove and the outside of the rail until there are no obvious water marks or bonded particles in the track bed groove and on the rail surface, which is regarded as the completion of the drying treatment; S5. Pretreatment before pouring: Lay a layer of PTEF Teflon fiberglass composite bonding tape on the bottom of the track bed groove, so that the bonding surface of the bonding tape adheres completely to the bottom interface of the track bed groove, and apply a layer of polymer elastic composite material adhesive on the side wall of the track bed groove; S6. Precise positioning of the rail: Based on the center line of the line, adjust the position of the rail in the track bed groove to ensure that the geometric profile of the gauge line meets the line requirements; when the position of the rail is adjusted, use fixed restraint elements to restrain and fix the position of the rail to ensure that the position of the rail is determined during the subsequent overall pouring of materials; S7. Overall pouring: Select a handheld or push - type pouring device according to the length of the replacement ballastless track, and pour the polymer elastic composite material into the track bed groove of the replacement section as a whole according to the specified mixing ratio. Before pouring, the polymer elastic composite material should be fully stirred, and ensure that the pouring process meets the requirements of continuous pouring, and ensure that the poured material is completely bonded to other sections.

[0029] When the ballastless track is initially laid in the present invention, before initially pouring the polymer elastic composite material, it is necessary to lay a layer of PTEF Teflon fiberglass composite bonding tape on the bottom of the track bed groove of the section to be poured as a whole; the PTEF Teflon fiberglass composite bonding tape should meet the requirements of the national standard GB / T39714.1 - 2020 "Plastics - Polytetrafluoroethylene (PTFE) Semi - finished Products". To ensure that in the overall structure removal link of the removal process, the bonding tape completely covers the entire bottom cross - section of the track bed groove and there is no bonding on the groove wall.

[0030] In step S2, the cutting machine used for cutting shall meet the requirements of the national standards GB / T 38196-2019 "Safety Requirements for Construction Machinery and Equipment - Floor Cutting Machines" and GB13960.11-2000 "Safety of Transportable Motor - Operated Tools - Part 2: Particular Requirements for Profile Cutting Machines". The cutting gear material is selected as ultra - high molecular weight polyethylene or nylon material.

[0031] Recommended values for cutting gear parameters: Module 4 - 6 Number of teeth 20 - 30 Pressure angle 20° - 25° Helix angle 15° - 20° Tooth width 30 - 50mm Addendum coefficient 1.0 - 1.25 Tooth root fillet radius 0.3 - 0.5mm.

[0032] In step S3, the cleaning solvent used in the cleaning work is an organic solvent prepared by mixing acetone CH3COCH3 and ethanol CH3CH2OH in a mass ratio of 4:1.

[0033] In step S5, the high - molecular elastic composite adhesive is a silane coupling agent prepared by mixing γ - glycidoxypropyltrimethoxysilane and γ - aminopropyltriethoxysilane components in a mass ratio of 2:1.

[0034] In step S6, the method of using fixed restraint elements to restrain and fix the position of the rail is the two - way restraint method. Multiple finished high - molecular elastic composite pads are used to support the bottom of the rail to control the vertical height of the track, and two finished high - molecular elastic composite products are synchronously set at the rail waist for lateral fixation to accurately position the rail in the bearing groove.

[0035] In step S7, the high - molecular elastic composite material used in the overall pouring is an existing technology, which can be composed of polysulfide rubber or single - component and double - component polyurethane prepolymer combined with a thickener, toughening agent, accelerator, and defoaming agent in a mass ratio of 72:17.5:0.05:1.5:0.2.

[0036] Steps S2, S3, and S4 can be carried out simultaneously according to the specified requirements to meet the more rapid construction requirements.

Claims

1. A ballastless track system, comprising a rail seat, a rail, and a polymer elastic composite material, characterized in that, A layer of PTEF Teflon fiberglass composite bonding tape is also laid on the bottom of the rail support groove. The bonding surface of the bonding tape is bonded to the bottom of the rail support groove, and the non-sticky surface of the bonding tape is in contact with the polymer elastic composite material.

2. A method for removing and replacing the polymer elastic composite material of the ballastless track system according to claim 1, characterized in that, It includes the following steps: S1. Confirm and clear the replacement section; S2. Overall cutting process: In the cleared replacement section, use a cutting machine to remove the polymer elastic composite material along the side wall of the rail support groove, and take out the overall structure of the polymer elastic composite material covering the rail; S3. Cleaning work: Use a cleaning solvent to completely clean the polymer elastic composite material on the inner wall of the rail support groove and the outer surface of the rail until there is no bonding phenomenon or attached particles in the rail support groove and on the surface of the rail, and place the rail outside the rail support groove to ensure that the rail is not re-contaminated; S4. Drying treatment: Use a blower to dry the inner wall of the rail support groove and the outside of the rail until there is no obvious water mark or bonding particles in the rail support groove and on the surface of the rail, which is regarded as the completion of the drying treatment; S5. Pretreatment before pouring: Lay a layer of PTEF Teflon fiberglass composite bonding tape on the bottom of the rail support groove, so that the bonding surface of the bonding tape completely adheres to the bottom interface of the rail support groove, and apply a layer of polymer elastic composite material adhesive on the side wall of the rail support groove; S6. Precise positioning of the rail: Based on the center line of the line, adjust the position of the rail in the rail support groove to ensure that the geometric shape of the gauge line meets the line requirements; when the position of the rail is adjusted, use a fixed restraint element to restrain and fix the position of the rail; S7. Overall pouring: Use a pouring device to pour the polymer elastic composite material into the rail support groove of the cleared replacement section as a whole, and ensure that the poured material is completely bonded to other sections.

3. A method for removing and replacing a polymer elastic composite material of a ballastless track system according to claim 2, characterized in that, When the ballastless track is initially laid, before initially pouring the polymer elastic composite material, a layer of PTEF Teflon fiberglass composite bonding tape needs to be laid on the bottom of the rail support groove of the section to be poured as a whole.

4. The method for removing and replacing the polymer elastic composite material of a ballastless track system according to claim 3, characterized in that, The PTEF Teflon fiberglass composite bonding tape shall meet the requirements of the national standard GB / T39714.1-2020 "Plastics - Polytetrafluoroethylene (PTFE) Semi-finished Products". To ensure that the bonding tape completely covers the entire bottom cross-section of the rail support groove during the overall structure removal process in the cutting process, and there should be no bonding on the groove wall.

5. A method for removing and replacing a polymer elastic composite material of a ballastless track system according to claim 2, characterized in that, In step S2, the cutting machine used for cutting shall meet the requirements of the national standards GB / T38196-2019 "Safety Requirements for Construction Machinery and Equipment - Floor Cutters" and GB13960.11-2000 "Safety of Portable Electric Tools - Part 2: Particular Requirements for Profile Cutters". The cutting gear material is selected from ultra-high molecular weight polyethylene or nylon materials.

6. The method for removing and replacing the polymer elastic composite material of a ballastless track system according to claim 2, characterized in that, The cleaning solvent used in step S3 for cleaning work is an organic solvent prepared by mixing acetone CH3COCH3 and ethanol CH3CH2OH in a mass ratio of 4:

1.

7. A method for removing and replacing the polymer elastic composite material of a ballastless track system according to claim 2, characterized in that, The polymer elastic composite material adhesive described in step S5 is a silane coupling agent prepared by mixing two components of γ-glycidyl ether oxypropyltrimethoxysilane and γ-aminopropyltriethoxysilane in a mass ratio of 2:

1.

8. A method for removing and replacing a polymer elastic composite material of a ballastless track system according to claim 2, characterized in that, The method of using fixed constraint elements to constrain and fix the position of the rail in step S6 is the two-way constraint method. Multiple finished polymer elastic composite material pads are used to support the bottom of the rail to control the vertical height of the track, and two finished polymer elastic composite materials are synchronously arranged at the rail waist to laterally fix the rail at the accurate position in the rail seat groove.

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