Construction beam and construction method for replacing railway tracks without stopping operation
By installing support, longitudinal beam, cross beam and reinforcement on the railway track, the problem of insufficient support strength of the sleepers is solved, the load strength of the railway track is improved, and the safety and stability of railway track replacement under constant operation conditions are ensured.
Patent Information
- Application Number
- CN202210212629.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-03-05
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2042-03-05
AI Technical Summary
In the prior art, when installing cross beams, the support strength of the sleepers is relatively weak, which affects the support strength of the sleepers to the rails.
Using supporting parts, longitudinal beams, cross beams and reinforcement components, by opening cross grooves and reinforcement grooves in the railroadbed, installing cross beams and compacting, the reinforcement and support plates support the rails, and using jacks or concrete blocks to enhance the load on the rails Strength and secure the cross beam and the block through a fixing mechanism.
The support strength of the railway tracks is improved, the safety and stability of railway track replacement under constant operation conditions are ensured, and effective support for the railway tracks is achieved.
Smart Images
Figure CN114606809B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of railway construction, and in particular to a construction beam and a construction method for replacing railway tracks without stopping operation. Background Art
[0002] At present, with the rapid development of the domestic economy, railway transportation plays a vital role in people's daily work and life, so the requirements for railways are getting higher and higher. In the process of use, there are problems with base diseases in tunnels. In order to improve the railway carrying capacity, it is necessary to increase the locomotive axle weight. The most fundamental solution to the treatment of tunnel base diseases is to replace the ballasted track in the tunnel with a ballastless track, which can not only improve the railway carrying capacity, but also reduce the problem of base diseases in the track.
[0003] The existing Chinese patent with the patent publication number CN106758590A proposes a construction beam and construction method for replacing railway tracks without stopping operation. The construction beam is used to be set at the track to be replaced, including: a roadbed beam support, a longitudinal beam, a cross beam and a track support assembly; in the installed state, the roadbed beam support is set below the roadbed surface of the track to be replaced, and longitudinal beams are arranged on both sides of the railway track. Each longitudinal beam is erected between adjacent roadbed beam supports along the direction of the railway track. A plurality of parallel cross beams are erected between the longitudinal beams, and the cross beams and the longitudinal beams are detachably fixed; a track support assembly is set between the cross beam and the rail to fix the rail on the cross beam. The rail is supported by the construction beam at the track to be replaced to meet the normal operation under the train load. After supporting the rail, during the window time, the original track facilities are dismantled, and the track facilities of the ballastless track are laid, and finally the construction beam is dismantled, thereby realizing the replacement of the railway track without stopping operation, which is safe, stable and efficient.
[0004] With respect to the above-mentioned related technologies, the inventors believe that when installing the crossbeam, it is necessary to dig a transverse groove between the sleepers. At this time, the supporting strength of the sleepers becomes relatively weak, thereby affecting the supporting strength of the sleepers for the rails. There is a defect that affects the supporting strength of the sleepers for the rails. Summary of the invention
[0005] In order to improve the problem of insufficient support strength for rails, the present application provides a construction beam and a construction method for replacing railway tracks without stopping operation.
[0006] The present application provides a construction beam for replacing railway tracks without stopping operation, which adopts the following technical solution:
[0007] A construction beam for replacing railway tracks without stopping operation, comprising a support, a plurality of longitudinal beams and a plurality of cross beams, the two ends of the cross beams being placed on the longitudinal beams, reinforcement members for supporting the rails being installed on both sides of the contact position between the cross beams and the rails, a placement groove for placing the cross beams being provided on the track subgrade, reinforcement grooves being provided on both sides of the placement grooves close to the rails, support plates for supporting the reinforcement members being installed in the reinforcement grooves.
[0008] By adopting the above technical solution, the support is placed under the roadbed of the original rail, and then the longitudinal beam is placed on the support. Before laying the cross beam, a transverse groove and a reinforcement groove are first excavated, the cross beam is installed in the transverse groove, and the bottom of the reinforcement groove is compacted. Then the support plate is laid, and the reinforcement on the support plate supports the rail, so that the reinforcement and the cross beam cooperate with each other to support the rail, ensuring the effect of supporting the strength of the rail.
[0009] Optionally, the reinforcement member is configured as a jack, the jack is placed on the support plate, and the force-bearing end of the jack abuts against the bottom surface of the rail.
[0010] By adopting the above technical solution, the jack supports the bottom surface of the rail to increase the load strength of the rail.
[0011] Optionally, the reinforcement is configured as a block made of concrete, the block is integrally provided with the support plate and the upper surface thereof abuts against the rail, and a fixing mechanism for facilitating installation is provided between the crossbeam and the reinforcement.
[0012] By adopting the above technical solution, the building blocks are used to support the rails, and the beams and the building blocks are fixed by a fixing mechanism, so that the building blocks and the beams support the rails together, thereby ensuring the load strength of the rails.
[0013] Optionally, the fixing mechanism includes a threaded rod, a fixing rod and an anchor assembly connected to the building block, the threaded rod is connected to the anchor assembly, the fixing rod is fixedly connected to the cross beam, the fixing rod is provided with a sliding threaded sleeve, the threaded sleeve is threadedly connected to the threaded rod, and a clamping assembly is provided between the fixing rod and the threaded sleeve.
[0014] Optionally, the clamping assembly includes a clamping ring and an abutment plate, the clamping ring is fixedly connected to one end of the threaded sleeve away from the threaded rod, the abutment plate is fixedly connected to one end of the fixed rod close to the threaded rod, the clamping ring is sleeved outside the fixed rod, and the clamping ring abuts against the abutment plate.
[0015] By adopting the above technical solution, the abutment plate is abutted against the end of the threaded rod, and the threaded sleeve is driven to be threadedly connected with the threaded rod, and the threaded sleeve drives the clamping ring to move toward the abutment plate. When the clamping ring abuts against the abutment plate, the threaded connection between the threaded rod and the threaded sleeve and the pulling action of the clamping ring and the abutment plate can achieve a stable fixation effect between the fixing rod and the threaded rod, thereby facilitating the fixation of the building blocks and the beams.
[0016] Optionally, the anchoring assembly includes a slide cylinder, an expansion assembly for strengthening the connection strength between the threaded rod and the block, and a limiter, the slide cylinder slides outside the threaded rod, and the limiter is used to limit the expansion angle of the expansion assembly.
[0017] By adopting the above technical solution, the slide cylinder is used to increase the outward expansion angle of the outward expansion component, and the limiter is used to limit the outward expansion angle of the outward expansion component, thereby achieving a firm fixation effect between the threaded rod and the building block.
[0018] Optionally, the outward expansion component includes a first reinforcement rod and a second reinforcement rod, one end of the first reinforcement rod is hinged to the outer wall of the slide tube, the other end of the first reinforcement rod is hinged to one end of the second reinforcement rod, and the other end of the second reinforcement rod is hinged to the bottom end of the threaded rod.
[0019] By adopting the above technical solution, when the slide tube slides, the first reinforcing rod and the second reinforcing rod swing outward, thereby increasing the stability of the connection between the building block and the threaded rod.
[0020] Optionally, the limiting member is fixedly connected to the threaded rod via a limiting ring, and the limiting ring abuts against one end of the sliding cylinder close to the first reinforcing rod.
[0021] By adopting the above technical solution, when the slide tube slides to abut against the limit ring, the first reinforcement rod and the second reinforcement rod expand outward to the maximum angle.
[0022] The present application also provides a construction method for replacing a construction beam of a railway track without stopping operation, which adopts the following technical solution:
[0023] A construction method for replacing a construction beam for a railway track without stopping operation comprises the following steps:
[0024] S1. Determine the technical parameters of the construction temporary beam and set up the support. After determining the technical parameters of the construction temporary beam, place the support under the roadbed surface of the track to be replaced;
[0025] S2, installing longitudinal beams and excavating transverse grooves, placing two longitudinal beams on the supports, and excavating transverse grooves and reinforcement grooves in adjacent sleeper members;
[0026] S3, installing the crossbeam and supporting the rails. The crossbeam is erected between the two longitudinal beams, and the support plate is placed after the bottom surface of the reinforcement groove is leveled, and the blocks are poured to support the rails, and the crossbeam and the blocks are connected by a fixing mechanism;
[0027] S4, tighten the temporary beam, and tighten the longitudinal beam to the cross beam and the cross beam to the rail;
[0028] S5. Replacement of ballastless track: remove the original sleepers, remove all the gravel in the replacement trackbed section and transport it away, install the track slab concrete base formwork, pour concrete, and lay the track slab after the track slab base has a certain strength.
[0029] Optionally, in S3, a jack may be placed on the support plate to support the rail.
[0030] By adopting the above technical scheme, according to the railway track conditions, including the environment and track conditions of the track, the technical parameters of the construction temporary beam include: length, width, width of the longitudinal beam of the construction temporary beam, width of the cross beam, and size of the support; after determining the technical parameters of the construction temporary beam, the support is placed under the roadbed surface of the track to be replaced; two longitudinal beams are placed on the support, and transverse grooves and reinforcement grooves are excavated in adjacent sleeper members, the length direction of the transverse groove is parallel to the length direction of the original sleeper, and the reinforcement groove is connected to the transverse groove; the cross beam is erected between the two longitudinal beams, and the bottom surface of the reinforcement groove is leveled and then a support plate is placed, and a jack is placed on the support plate to support the rail, or a fixing machine is used to fix the rail. The structure connects the crossbeam and the blocks, and the threaded connection between the threaded sleeve and the threaded rod and the abutment between the clamping ring and the abutment plate are used to achieve the fixing effect between the fixing rod and the threaded rod. At the same time, the first reinforcing rod and the second reinforcing rod are driven to expand outward by the sliding cylinder, and then the outward expansion assembly and the support plate are used to support the enclosure, and then the concrete is poured. After the block curing is completed, the rails are supported; the longitudinal beams and the crossbeams are fixed by bolts, and the crossbeams and the rails are fastened by rail spring fasteners; the original sleepers are removed, all the gravel in the replacement track bed section is removed and transported away, the track slab concrete base template is installed, concrete is poured, and the track slab is laid after the track slab base has a certain strength.
[0031] In summary, the present application includes at least one of the following beneficial technical effects:
[0032] 1. Place the support under the roadbed of the original rail, then place the longitudinal beam on the support, dig the transverse groove and the reinforcement groove before laying the cross beam, install the cross beam in the transverse groove, and tamp the bottom of the reinforcement groove, then lay the support plate, and the reinforcement on the support plate supports the rail, so that the reinforcement and the cross beam cooperate with each other to support the rail, ensuring the effect of the support strength of the rail;
[0033] 2. Abut the abutment disk with the end of the threaded rod, and then drive the threaded sleeve to be threadedly connected with the threaded rod, and the threaded sleeve drives the clamping ring to move toward the abutment disk. When the clamping ring abuts the abutment disk, the threaded rod and the threaded sleeve are threadedly connected, and the clamping ring and the abutment disk are pulled together to achieve a firm fixation effect between the fixed rod and the threaded rod. BRIEF DESCRIPTION OF THE DRAWINGS
[0034] Figure 1 It is a schematic diagram of the overall structure of the first embodiment of the present application;
[0035] Figure 2 is a schematic diagram of a beam, a rail, a reinforcement member and an anchor assembly in Example 1 of the present application;
[0036] Figure 3 is a schematic diagram of a fixing rod, a threaded rod, a fixing mechanism and an anchoring assembly in Embodiment 1 of the present application;
[0037] Figure 4 It is a structural diagram of Embodiment 2 of the present application;
[0038] Figure 5 This is the process flow chart of Example 3 of the present application.
[0039] Figure numerals: 1. support; 2. longitudinal beam; 3. cross beam; 4. placement groove; 5. support plate; 6. jack; 7. building block; 8. threaded rod; 9. fixing rod; 10. clamping ring; 11. abutment plate; 12. outward expansion component; 13. first reinforcing rod; 14. second reinforcing rod; 15. limiting ring; 16. slide cylinder; 17. reinforcement; 18. rail; 19. reinforcement groove; 20. threaded sleeve. DETAILED DESCRIPTION
[0040] The following is combined with Figure 1-5 This application is described in further detail.
[0041] Embodiment 1
[0042] The present application discloses a construction beam for replacing railway tracks without stopping operation. Figure 1 and Figure 2 The construction beam used for replacing railway tracks without stopping operation includes a support 1, two longitudinal beams 2 and a plurality of parallel cross beams 3. The cross beams 3 are staggered with the original sleepers, and both ends of the cross beams 3 are placed on the longitudinal beams 2. The cross beams 3 are used to support the load of the rails 18. A placement groove 4 for placing the cross beam 3 is opened on the track subgrade. The cross beam 3 is placed along the length direction of the placement groove 4, and the width of the placement groove 4 is larger than the width of the cross beam 3, which is convenient for installing the cross beam 3.
[0043] Reference Figure 1 and Figure 2In order to support the rails 18, reinforcement grooves 19 are provided on both sides of the placement grooves 4 close to the rails 18, the reinforcement grooves 19 are connected to the placement grooves 4, and reinforcement members 17 for supporting the rails 18 are installed on both sides of the contact position between the crossbeam 3 and the rails 18, and support plates 5 for supporting the reinforcement members 17 are installed in the reinforcement grooves 19. The support plates 5 are used to provide a support platform for the reinforcement members 17. When the crossbeam 3 is installed, the reinforcement members 17 are used to support the rails 18 to further ensure the normal operation of the train on the rails 18; the reinforcement members 17 are configured as blocks 7 made of concrete, the blocks 7 are integrally arranged with the support plates 5 and the upper surfaces are in contact with the rails 18. In order to achieve the effect of the blocks 7 and the crossbeam 3 jointly supporting the rails 18, a fixing mechanism for easy installation is provided between the crossbeam 3 and the reinforcement members 17.
[0044] Reference Figure 2 and Figure 3 The fixing mechanism includes a threaded rod 8, a fixing rod 9 and an anchoring assembly connected to the building block 7. The threaded rod 8 is connected to the anchoring assembly. The fixing rod 9 is fixedly connected to the side wall of the beam 3. The fixing rod 9 is sleeved with a sliding threaded sleeve 20. The threaded sleeve 20 is threadedly connected to the threaded rod 8. A clamping assembly is arranged between the fixing rod 9 and the threaded sleeve 20. The clamping assembly includes a clamping ring 10 and an abutment plate 11. The clamping ring 10 is fixedly connected to the section of the threaded sleeve 20 away from the threaded rod 8. The abutment plate 11 is fixedly connected to one end of the fixing rod 9 close to the threaded rod 8. The clamping ring 10 is sleeved outside the fixing rod 9.
[0045] The abutment disk 11 is abutted against the end of the threaded rod 8, and the threaded sleeve 20 is driven to be threadedly connected with the threaded rod 8. The threaded sleeve 20 drives the clamping ring 10 to move toward the abutment disk 11. When the clamping ring 10 abuts against the abutment disk 11, the threaded connection between the threaded rod 8 and the threaded sleeve 20 and the pulling action of the clamping ring 10 and the abutment disk 11 achieves a firm fixation effect between the fixing rod 9 and the threaded rod 8, thereby achieving a fixing effect on the crossbeam 3 and the anchor assembly.
[0046] Reference Figure 2 and Figure 3 The anchoring assembly includes a slide 16, an expansion assembly 12 for strengthening the connection strength between the threaded rod 8 and the building block 7, and a limit piece. The slide 16 slides outside the threaded rod 8. The expansion assembly 12 includes a first reinforcement rod 13 and a second reinforcement rod 14. One end of the first reinforcement rod 13 is hinged to the outer wall of the slide 16, the other end of the first reinforcement rod 13 is hinged to one end of the second reinforcement rod 14, and the other end of the second reinforcement rod 14 is hinged to the bottom end of the threaded rod 8. The first reinforcement rod 13 and the slide 16, the second reinforcement rod 14 and the first reinforcement rod 13, and the second reinforcement rod 14 and the threaded rod 8 are all hinged through a hinge shaft, and the axial direction of the hinge shaft is horizontally set and arranged along a direction perpendicular to the axial direction of the threaded rod 8.
[0047] The limiter is used to limit the outward expansion angle of the outward expansion component 12. The limiter is set as a limit ring 15. The limit ring 15 abuts against one end of the slide 16 close to the first reinforcement rod 13. When the slide 16 is driven to move toward the bottom end of the threaded rod 8, the first reinforcement rod 13 and the second reinforcement rod 14 are swung outward at their hinged positions. When the slide 16 moves to a position abutting against the limit ring 15, the first reinforcement rod 13 and the second reinforcement rod 14 swing to their maximum angle.
[0048] At this time, the driving support plate 5 and the reinforcement groove 19 are reinforced with support panels, and concrete is poured into the support space. After the concrete pouring is completed, the top surface of the block 7 is ensured to abut against the bottom surface of the rail 18. At this time, under the anchoring action of the first reinforcing rod 13 and the second reinforcing rod 14, the strength of the connection between the beam 3 and the block 7 is strengthened, so that the beam 3 and the block 7 can support the rail 18 together, ensuring the effect of replacing the railway track without stopping operation.
[0049] The implementation principle of the construction beam and construction method of the embodiment of the present application for replacing railway tracks without stopping operation is as follows: the end of the threaded rod 8 is abutted against the abutment plate 11, and the threaded sleeve 20 is driven to be threadedly connected with the threaded rod 8. When the clamping ring 10 moves to the position of the abutment plate 11, the fixing effect of the threaded rod 8 and the fixing rod 9 is achieved. At this time, the slide 16 is pushed to move, and the first reinforcing rod 13 and the second reinforcing rod 14 swing outward. When the slide 16 moves to the position of the limit ring 15, the first reinforcing rod 13 and the second reinforcing rod 14 swing to the maximum angle; the support plate 5 and the anchoring assembly are reinforced and supported, and concrete is poured after the support is completed. After the concrete is cured, the construction of the block 7 is completed, and it is ensured that the beam 3 and the block 7 are firmly fixed, so that the beam 3 and the block 7 jointly support the rail 18.
[0050] Embodiment 2
[0051] Reference Figure 1 and Figure 4 The difference between the second embodiment and the first embodiment is only the reinforcement member 17. The reinforcement member 17 is configured as a jack 6. The jack 6 is placed on the support plate 5. The force-bearing end of the jack 6 abuts against the bottom surface of the rail 18. The jack 6 is used to support the rail 18 and enhance the load strength of the rail 18.
[0052] Embodiment 3
[0053] Reference Figure 5 The present application also discloses a construction method for replacing a construction beam for railway track without stopping operation. The construction method for replacing a construction beam for railway track without stopping operation includes the following steps:
[0054] S1. Determine the technical parameters of the construction beam and set up the support 1. According to the railway track conditions, including the environment and track conditions of the track, the technical parameters of the construction beam include: length, width, width of the longitudinal beam 2 and the width of the cross beam 3 of the construction beam, and the size of the support 1. After determining the technical parameters of the construction beam, place the support 1 under the roadbed surface of the track to be replaced;
[0055] S2, installing the longitudinal beam 2 and excavating the transverse groove, placing the two longitudinal beams 2 on the support 1, and excavating the transverse groove and the reinforcement groove in the adjacent sleeper parts, the length direction of the transverse groove is parallel to the length direction of the original sleeper, and the reinforcement groove is connected with the transverse groove;
[0056] S3, install the crossbeam 3 and support the rail 18, the crossbeam 3 is erected between the two longitudinal beams 2, and the support plate 5 is placed after the bottom surface of the reinforcement groove 19 is leveled, and the jack 6 is placed on the support plate 5 to support the rail 18, or the crossbeam 3 and the block 7 are connected by a fixing mechanism, and the threaded sleeve 20 is threadedly connected to the threaded rod 8 and the clamping ring 10 is abutted against the abutment plate 11 to achieve the fixing effect between the fixing rod 9 and the threaded rod 8, and at the same time, the first reinforcement rod 13 and the second reinforcement rod 14 are driven to expand outward through the slide 16, and then the expansion assembly 12 and the support plate 5 are used to support the enclosure, and then concrete is poured, and the block 7 is cured to support the rail 18;
[0057] S4, fasten the temporary beam, fix the longitudinal beam 2 and the cross beam 3 by bolts, and fasten the cross beam 3 and the rail 18 by rail spring fasteners;
[0058] S5. Replacement of ballastless track: remove the original sleepers, remove all the gravel in the replacement trackbed section and transport it away, install the track slab concrete base formwork, pour concrete, and lay the track slab after the track slab base has a certain strength.
[0059] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A construction beam for replacing railway tracks without stopping operation, characterized in that: The invention comprises a support (1), a plurality of longitudinal beams (2) and a plurality of transverse beams (3), wherein both ends of the transverse beams (3) are placed on the longitudinal beams (2), and both sides of the contact position between the transverse beams (3) and the rails (18) are provided with reinforcing members (17) for supporting the rails (18), a placement groove (4) for placing the transverse beams (3) is provided on the track subgrade, and both sides of the placement grooves (4) close to the rails (18) are provided with reinforcing grooves (19), and support plates (5) for supporting the reinforcing members (17) are installed in the reinforcing grooves (19), and the reinforcing members (17) are provided as blocks (7) made of concrete, and the blocks (7) and the support plates (5) are integrally provided and the upper surfaces thereof are in contact with the rails (18), and a fixing mechanism for facilitating installation is provided between the transverse beams (3) and the reinforcing members (17); the fixing mechanism comprises a threaded A rod (8), a fixing rod (9) and an anchoring assembly connected to the building block (7), the threaded rod (8) being connected to the anchoring assembly, the fixing rod (9) being fixedly connected to the crossbeam (3), the fixing rod (9) being sleeved with a sliding threaded sleeve (20), the threaded sleeve (20) being threadedly connected to the threaded rod (8), a clamping assembly being arranged between the fixing rod (9) and the threaded sleeve (20); the clamping assembly comprising a clamping ring (10) and an abutting plate (11), the clamping ring (10) being fixedly connected to an end of the threaded sleeve (20) away from the threaded rod (8), the abutting plate (11) being fixedly connected to an end of the fixing rod (9) close to the threaded rod (8), the clamping ring (10) being sleeved outside the fixing rod (9), and the clamping ring (10) abutting against the abutting plate (11).
2. The construction beam for replacing railway tracks without stopping operation according to claim 1 is characterized in that: The anchoring assembly comprises a slide cylinder (16), an expansion assembly (12) for strengthening the connection strength between the threaded rod (8) and the building block (7), and a stopper, wherein the slide cylinder (16) slides outside the threaded rod (8), and the stopper is used to limit the expansion angle of the expansion assembly (12).
3. The construction beam for replacing railway tracks without stopping operation according to claim 2 is characterized in that: The outward expansion component (12) comprises a first reinforcing rod (13) and a second reinforcing rod (14), one end of the first reinforcing rod (13) being hinged to the outer wall of the slide cylinder (16), the other end of the first reinforcing rod (13) being hinged to one end of the second reinforcing rod (14), and the other end of the second reinforcing rod (14) being hinged to the bottom end of the threaded rod (8).
4. The construction beam for replacing railway tracks without stopping operation according to claim 3 is characterized in that: The limiting member and the threaded rod (8) are fixedly connected to a limiting ring (15), and the limiting ring (15) abuts against one end of the slide cylinder (16) close to the first reinforcing rod (13).
5. A construction method for a construction beam for replacing a railway track without stopping operation, based on the construction beam for replacing a railway track without stopping operation according to any one of claims 1 to 4, characterized in that: The steps include: S1. Determine the technical parameters of the construction temporary beam and set up the support (1). After determining the technical parameters of the construction temporary beam, place the support (1) below the roadbed surface of the track to be replaced; S2, installing the longitudinal beams (2) and excavating transverse grooves, placing two longitudinal beams (2) on the support (1), and excavating transverse grooves and reinforcement grooves in adjacent sleeper members; S3, installing the cross beam (3) and supporting the rail (18), the cross beam (3) being erected between the two longitudinal beams (2), and placing the support plate (5) after leveling the bottom surface of the reinforcement groove (19), pouring the building blocks (7) to support the rail (18), and connecting the cross beam (3) and the building blocks (7) through a fixing mechanism; or placing a jack (6) on the support plate (5) to support the rail (18); S4, fastening the temporary beam, fastening the longitudinal beam (2) and the cross beam (3) and the cross beam (3) and the rail (18); S5. Replacement of ballastless track: remove the original sleepers, remove all the gravel in the replacement trackbed section and transport it away, install the track slab concrete base formwork, pour concrete, and lay the track slab after the track slab base has a certain strength.