Method for laying jointed ballasted track for trams on small-radius curves

Abstract

The present invention relates to the field of tram track laying construction. Disclosed is a method for laying a jointed ballasted track for trams on small-radius curves. In the method, by adjusting and fixing track alignment before ballast laying and track finishing, the conventional construction sequence of ballast laying and track finishing is changed, track lifting and alignment adjustment for small-radius curves are carried out prior to ballast laying and tamping, and during track laying, sleepers are densely arranged at rail joints, and concrete buttresses are added beside the sleepers to secure the sleepers in place and counteract the bending stress of rails, ensuring precise control of track alignment and elevation on the small-radius curves, and realizing laying of the jointed ballasted track for trams on the small-radius curves. After construction, ballast laying and track finishing on the small-radius curves can meet track operation requirements in a single pass, ensuring smooth and safe tram operation.

Description

Method for laying ballast track on small-radius curve tram jointed lines Technical Field

[0001] This invention relates to the field of tram track laying construction, specifically to a method for laying ballast track on a small-radius curved tram line with joints. Background Technology

[0002] When there is a significant overlap between the location of a subway station and an existing operating tram line, the tram line must be temporarily rerouted before subway construction can proceed on the overlapping section. According to the "Subway Design Code," a curve radius of less than 350m is considered a small-radius curve. Due to site limitations, the curve radius for temporary tram rerouting projects is less than 350m. On small-radius curves, it is extremely difficult to pre-bend the rails using rail benders. Furthermore, at the joints of small-radius curves, the rails are not easily bent, resulting in a V-shape without external force, which does not meet the requirements for line smoothness.

[0003] Chinese patent CN106368089B discloses a construction method for laying and controlling the alignment of tram tracks with small radius curves. The method includes steps such as: construction preparation; surveying and setting out; long rail traction; long rail guiding and bending; temporary fixing of long rails; track panel support; fastener assembly; and track fine-tuning. This method uses standard steel rails welded into long rails, which are then pulled to the desired laying position using rail clamps and a winch. Pulleys and guide pulleys are placed at the target positions on the rails, and temporary fixing is performed simultaneously with the traction. Finally, fine-tuning is performed to complete the arrangement of the long rails in the designed positions. The main problem this method addresses is how to ensure the smoothness of the curve at the curved sections of the track, overcoming the shortcomings of existing technologies that use rail straighteners to pre-bend the rails, which cannot guarantee a constant value for the track curvature, leave significant and irreversible deformation at the track's stress points, and involve numerous and inefficient steps.

[0004] However, this method still cannot solve the problem that it is extremely difficult to pre-bend the rails using a rail bender on small radius curves, and that the rails at the joints on small radius curves are not easily bent, resulting in a V-shape without external force, which cannot meet the requirements for track smoothness.

[0005] Summary of the Invention

[0006] The problem this invention aims to solve is: how to achieve the laying of ballast track on jointed tram lines with small radius curves, and ensure that the track alignment control of small radius curves meets the requirements for operational smoothness.

[0007] The technical solution adopted in this invention is a method for laying ballasted track on jointed tram lines with small radius curves, comprising the following steps:

[0008] S1. Construction preparation: Measure and verify the roadbed elevation, and lay out the center stakes and side stakes of the line;

[0009] S2. Ballast laying: Measure and mark out the outer edge of the ballast laying, calculate the required ballast height for each section based on the loose laying coefficient, and then spread and compact the ballast.

[0010] S3. Laying sleepers: Based on the survey and layout, use the left side of the track and the outer rail of the curve as the basic rail and square the basic rail sleepers; spread sleepers on the ballast; according to the sleeper placement position on the track section table, locate the sleepers by measurement; on small radius curves, fix one sleeper every 3 meters by driving two ground anchors within the width of the sleeper; and densely arrange sleepers at the rail joint positions on small radius curves, and add additional support rods for fixation.

[0011] S4. Rail and fastener installation: When laying the rails, after the gauge at the small radius curve joint position is controlled to the design value, the fishtail clamps are connected.

[0012] S5. Ballasting and straightening: Gradually straighten the newly laid track;

[0013] S6. Measurement and verification: Perform plane and elevation measurements and verifications on the centerline and curve elements of the track line, check whether the track gauge widening and curve superelevation meet the design requirements, ensure the line is accurate, and check along the entire length of the line whether the sleepers are square, whether the rail fasteners and joint plates are installed correctly, and whether the bolts are tightened.

[0014] S7. Pier Construction: After all checks and verifications are completed, a four-sleeper-sized area is excavated on the outside of the sleepers at the joint of the small-radius curve. Reinforced concrete piers are then constructed to abut the ends of the four sleepers.

[0015] Furthermore, in step S2 above, the ballast is controlled to be 3-5cm lower than the design elevation after compaction.

[0016] Furthermore, in step S3 above, the sleeper spacing at the rail joint location on the small radius curve is 550mm. For curve radii of 50≤R<100m, three additional support rods are added to the sleepers before and after the joint. For curve radii of R≥100m, two additional support rods are added to the sleepers before and after the joint. Ground anchors are installed 1 meter away from both sides of the sleepers. The two ends of the support rods are fixedly connected to the sleepers and the corresponding ground anchors, respectively. The direction of the support rods is straight with the sleepers and aligns the sleepers.

[0017] Furthermore, the ballast alignment work in step S5 above includes square the sleepers, replenishing and tightening accessories and fasteners, straightening the track direction, tamping the ballast under the sleepers at the rail bearing points, and eliminating superelevation and triangular pits. The specific steps are as follows:

[0018] (1) Alignment: Align the track to the center line position, with a deviation of less than 30mm from the center line of the track;

[0019] Square sleepers: After alignment, straighten the bent and slanted sleepers to ensure that the spacing and slant of the sleepers are controlled within 2cm;

[0020] (2) Ballasting: After the track is laid, the ballast is evenly distributed in the track by machinery or manual labor;

[0021] (3) Track lifting: Use a hydraulic track lifting machine to raise each section of track at several points and padded with ballast. The amount of track lifting at one time shall not exceed 15cm. The track shall be raised to the design elevation and slightly increased by 10mm for settlement. The outer rail of the curve shall be raised to the required superelevation. After track lifting, the front-to-back height deviation of the track shall be ≤5mm and the left-to-right horizontal deviation shall be ≤5mm. When lifting the track, first check the elevation of one rail (the inner rail for curves), and adjust the elevation of the other rail accordingly. The elevation deviation shall be -30 to +50mm.

[0022] (4) Ballast filling: After the road is started, the ballast at the shoulder is filled into the sleeper box;

[0023] (5) Tamping: Tamp the ballast within 45cm of the outer and inner sides of the rail, and tamping is strictly prohibited within 60cm of the middle of the sleeper; strengthen the tamping range below the rail, rail joints and outer strands of curves;

[0024] (6) Track alignment: Correct the horizontal position of the track and make the center line of the track consistent with the center of the track; repair the track bed, replenish the ballast in the sleeper box, compact the side slope and top surface of the track bed and keep it stable; straighten the track, correct the hard bends of the rails to achieve a straight and smooth appearance from a distance, level small depressions when starting the track, and correct the horizontal level and vertical height of the rails; align the sleepers and tighten the fasteners;

[0025] (7) Tightening: Tighten the joint bolts daily to ensure that the torque reaches more than 500 N.m. Tighten the rail fasteners regularly, and keep the torque between 100 and 140 N.m.

[0026] Furthermore, in step S7 above, the support is 2.5m long, 1m wide, and more than half the height from the top surface of the roadbed to the end face of the sleeper. A double-layered, bidirectional steel mesh is arranged. The concrete support wraps around the prestressed steel bars of the positioned sleeper and fits tightly against the sleeper. The vertical steel bars are implanted into the roadbed. After the concrete strength reaches 100%, the support structure is removed.

[0027] Furthermore, the track bed constructed using this method is a crushed stone track bed, and the rails are laid using jointed track, 59R2 grooved rails with a bottom width of 180mm and no bottom slope. The width of the rail bearing groove is 355mm, and the distance from the center line of the rail bearing groove on both sides to the center line of the sleeper is 734.625mm. Anchoring holes are provided on both sides of the rail bearing groove. The rails used are 25m standard rails, and the fastening accessories are type I elastic clip fasteners. The rail slope at the gauge baffle fastening position of the type I elastic clip fastener is 1:10.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] The present invention provides a method for laying ballasted track on a small-radius curved tram line with joints, which enables the laying of ballasted track with a curve radius of 50m. Furthermore, the ballasted track on the small-radius curve can meet the line operation conditions in one go, ensuring smooth and safe train operation, and achieving good technical and economic benefits.

[0030] In addition to the effects described above, the present invention also has the following advantages:

[0031] (1) Concrete supports are used at the joints of small-radius curves, which can effectively fix the track alignment, ensure the stability of the line in later operation, and reduce the investment in later operation, maintenance and upkeep.

[0032] (2) Increase the density of sleepers at the rail joint locations on small-radius curves to enhance the stability of the rail joints;

[0033] (3) First, adjust the position of the fixed small radius curve track joint, then raise the track to the design elevation, adjust the track geometry to the specified range, and finally tamp the ballast to avoid secondary adjustment of the track linearity after the track is raised.

[0034] (4) Small radius curves first complete the track setting and alignment adjustment, which makes it easier to interchange the positions of the spring bar type I fasteners for track gauge adjustment, reducing the manual and mechanical input for secondary track gauge adjustment and improving work efficiency;

[0035] (5) It requires less machinery and equipment, reduces labor input, is easy to operate, and can effectively improve work efficiency. Attached Figure Description

[0036] Figure 1 is a flowchart of the method for laying ballasted track on jointed tram lines with small radius curves.

[0037] Figure 2 is a schematic diagram of the strut installation;

[0038] Figure 3 is a schematic diagram of the support rods and piers for fixing the steel rails;

[0039] Figure 4 is a top view of the pier;

[0040] Figure 5 is a schematic diagram of the sleeper structure;

[0041] Figure 6 is a schematic diagram of the installation of the spring clip accessories;

[0042] Figure 7. Schematic diagram of the track gauge baffle structure;

[0043] Figure 8 is a schematic diagram of the working side clamping plate structure of the fishtail clamping plate;

[0044] Figure 9 is a schematic diagram of the non-working side clamping plate structure of the fishtail clamping plate;

[0045] The diagram is labeled as follows: 1. Support pier, 2. Sleeper, 201. Rail support groove, 3. Support rod, 4. Ground anchor, 5. Roadbed, 6. Vertical reinforcement, 7. Circumferential reinforcement, 8. Diagonal reinforcement, 9. Elastic strip, 10. Gauge baffle, 11. Baffle seat, 12. Spiral spike, 13. Nut. Detailed Implementation

[0046] The present invention will be further explained and described below with reference to the accompanying drawings to enable those skilled in the art to better understand it.

[0047] Example 1

[0048] Please refer to Figure 1-9 for the method of laying ballasted track on jointed tram lines with small radius curves, which includes the following steps:

[0049] S1. Construction preparation: Measure and verify the roadbed elevation, and lay out the center stakes and side stakes of the line;

[0050] S2. Ballast laying: Measure and lay out the outer edge of the ballast laying, calculate the required ballast height for each section based on the loose laying coefficient, and then spread and compact the ballast. Control the compacted ballast to be 3 to 5 centimeters lower than the design elevation to reduce the need for track alignment adjustments during the later track raising process of small radius curves.

[0051] S3. Install sleepers: Based on the measurement and layout, take the left side of the track and the outer rail of the curve as the basic rail. After the basic rail is set, use a square caliper to square the sleepers.

[0052] Once the base rail is determined, sleepers 2 are first laid out on the ballast. Based on the sleeper placement according to the track section schedule, and through measurement and positioning, on small-radius curves, one sleeper is fixed every 3 meters using two ground anchors within the width of sleeper 2. The ground anchors are made of 32mm round steel, with their bottoms extending below the base. Sleepers 2 are densely arranged at rail joint locations on small-radius curves, with a spacing of 550mm. A support rod 3 is added to one side of each sleeper 2 for fixation. For curve radii of 50 ≤ R < 100 meters, three support rods are added before and after each rail joint. For curves with a radius of ≥100 meters, two additional support rods 3 are installed on each of the sleepers before and after the joint. Ground anchors 4 are installed 1 meter apart on both sides of the sleeper 2. The two ends of the support rods 3 are fixedly connected to the sleeper 2 and the corresponding ground anchors 4, respectively. The ground anchors 4 are fixedly connected to the roadbed 5. The support rods 3 and the sleeper 2 are kept in a straight line, and the length of the support rods 3 is adjustable to facilitate installation and to align the sleeper 2. This ensures that the sleeper 2 will not move after the rail is installed, and the curve will not be deformed. It also reduces the problem of the sleeper 2 not being squared according to the curve shape and the large amount of adjustment required for the curve shape during subsequent ballast laying and track grading.

[0053] S4. Rail and fastener installation: When laying the rail, the track gauge at the joint position of the small radius curve must be controlled to the design value before connecting the fishtail plate. This is to avoid adjusting the track gauge after the joint is connected, which would affect the joint and cause secondary construction.

[0054] S5. Ballast Preparation and Track Straightening: Manual ballast preparation and track straightening is the process of gradually straightening newly laid track using manual labor and small machinery during each ballast replenishment. The key points of this work are: square the sleepers, replenish and tighten accessories and fasteners, straighten the track direction, solidify the ballast under the sleepers at the rail bearing points, and eliminate superelevation and triangular pits. Specific steps are as follows:

[0055] (1) Alignment: Align the track to the center line position, with a deviation of less than 30mm from the center line of the track;

[0056] (2) Square sleepers: After the track is cleared, the bent and slanted sleepers must be squared to ensure that the spacing and slant of the sleepers are controlled within 2cm.

[0057] (3) Ballasting: After the track is laid, the ballast is evenly distributed in the track by machinery or manual labor;

[0058] (4) Track lifting: Use a hydraulic track lifting machine to raise each section of track at several points and padded with ballast. The lifting amount at one time should not exceed 15cm. The track should be raised to the design elevation and slightly increased by 10mm for settlement. The outer rail of the curve should be raised to the required superelevation. After track lifting, the front-to-back height deviation of the track should be ≤5mm and the left-to-right horizontal deviation should be ≤5mm. When lifting the track, first check the elevation of one rail. The curve is the inner rail. Adjust the elevation of the other rail accordingly. The elevation deviation of the rail should be -30 to +50mm.

[0059] (5) Ballast filling: After the road is laid, the ballast at the shoulder should be filled into the sleeper box so that it can be effectively compacted;

[0060] (6) Tamping: The ballast within a 45cm range on the outer and inner sides of the rails shall be tamped to withstand the load of passing trains. Tamping is strictly prohibited within a 60cm range in the middle of the sleepers; tamping should be strengthened under the rails, and the tamping range of rail joints and outer strands of curves should be strengthened; when tamping manually, five requirements should be met, namely: sufficient height of the pick, sufficient tamping force, sufficient eight-sided pick, sufficient number of tamping picks, and sufficient tamping width, in order to ensure the quality of tamping;

[0061] (7) Track alignment: Correct the horizontal position of the track and make the center line of the track consistent with the center of the track; repair the track bed, replenish the ballast in the sleeper box, compact the side slope and top surface of the track bed and keep it stable; straighten the track, correct the hard bends of the rails to achieve a straight and smooth appearance from a distance, level small depressions when starting the track, and correct the horizontal level and vertical height of the rails; align the sleepers and tighten the fasteners.

[0062] (8) Tightening: The joint bolts should be tightened daily to ensure that the torque reaches more than 500 N.m. The rail fasteners should be tightened regularly, and the torque must always be kept between 100 and 140 N.m.

[0063] S6. Measurement and Verification: Perform plane and elevation measurements and verifications on the centerline and curve elements of the track line, and check whether the track gauge widening and curve superelevation meet the design requirements to ensure the accuracy of the line. Check along the entire length of the line whether the sleepers are square, whether the rail fasteners and joint plates are installed correctly, and whether the bolts are tightened.

[0064] S7. Pier Construction: After all checks and verifications are completed, an area the size of four sleepers is excavated on the outside of the sleepers at the joint of the small-radius curve. Reinforced concrete piers are constructed to abut the ends of the four sleepers. The top surface of the pier is more than half and less than two-thirds of the height of the sleeper end face; as shown in Figure 2, pier 1 is 2.5m long, 1m wide, and its height extends from the end face of the roadbed 5 to the top of the sleeper 2. One side of pier 1 abuts against the end faces of the four sleepers 2 before and after the joint, and its bottom is fixed to the roadbed 5. Multiple vertical reinforcing bars 6 are arranged inside pier 1, with their lower ends embedded in the roadbed 5. These vertical reinforcing bars 6 are spaced apart and fixed by circumferential reinforcing bars 7 arranged at the top and middle. Diagonal reinforcing bars 8 are also included, with their ends welded to the top of the left vertical reinforcing bar 6 and the bottom of the right vertical reinforcing bar 6. After the concrete strength reaches 100%, the strut 3 structure is removed. Concrete grade ≥ C30, reinforcing bar grade ≥ C12.

[0065] The track bed for the small-radius curved tram jointed line uses a crushed stone track bed. The rails are the same 59R2 channel rails as the original line, with a bottom width of 180mm and no bottom slope. The sleepers are improved Type II sleepers, and the fastening fittings are improved Type I elastic clip fasteners. The rails are 25m standard gauge. The improved sleeper 2 is 2500mm long, the rail groove 201 is 355mm wide, and the distance from the centerline of both rail grooves 201 to the centerline of the rail is 734.625mm. Anchor holes are provided on both sides of the rail groove 201.

[0066] The elastic clip fastener includes an elastic clip 9 and a gauge baffle 10 located above the sleeper 2. The rear end of the gauge baffle 10 abuts against the baffle seat 11, and the front end is in close contact with the rail bottom. The baffle seat 11 is in close contact with the sleeper shoulder. The elastic clip 9 is installed on the gauge baffle 10 and is connected and fastened by matching spiral spikes 12 and nuts 12. The chin of the middle front end of the elastic clip 9 contacts the gauge baffle 10, and the torque of the nut 13 is maintained at 100-140 N.m. The rail slope at the gauge baffle fastening position is 1:10.

[0067] Application Examples

[0068] The temporary rerouting project for Tram Line 1 in a certain city involves a new line with a total length of 472.289m. The line includes 5 small-radius curves, with the smallest radius curve being 50m long and 103m in length. The track bed is made of crushed stone, and the rails are the same 59R2 grooved rails as the original line, laid in a jointed track. The sleepers are the improved Type II sleepers, and the fastening accessories are the improved Type I elastic clip fasteners. The rails are 25m standard gauge.

[0069] By adopting this method during construction, all procedures, from laying the ballast, placing the sleepers, installing rail fasteners, and raising and aligning the track, can be completed in one go, greatly saving construction time. Furthermore, because concrete reinforcement is used at the joints of small-radius curves, the safety of train operation after the line is connected is ensured, the workload of subsequent track maintenance is reduced, and the difficulty of maintenance and construction is lowered. It has extremely high value for promotion and application in similar projects in the future.

[0070] Economic benefits

[0071] Compared to traditional laying methods, this method, which adopts the process of "adjusting and fixing the track shape first, and then laying ballast and straightening the track," increases the input of materials such as top supports and concrete piers, as well as corresponding personnel. However, because the method addresses the issue of small-radius curves during implementation, the track laying progress is faster. It also avoids problems such as the quadratic squareness of sleepers and issues with track shape and gauge on curves in the later stages, greatly reducing the input of construction machinery and personnel required for later track shape processing. The method can reduce construction costs while ensuring the quality of track construction.

[0072] (1) Investment in materials such as top supports and pier concrete, and construction personnel: RMB 15,000

[0073] (2) Activity Benefits:

[0074] Saved machinery costs: 20 days × 1 unit × 1500 yuan / day = 30,000 yuan

[0075] Savings on migrant worker costs: 20 days × 20 people × 220 yuan / day = 88,000 yuan

[0076] Savings in employee wages: 20 days × 40 people × 280 yuan / day = 224,000 yuan

[0077] Conclusion: The economic benefits achieved by this method are 22.4 + 8.8 + 3 - 1.5 = 32.7 million yuan.

[0078] Social benefits

[0079] The control of the alignment of small-radius curves is implemented in advance before track laying, which speeds up the track laying process and avoids problems such as the quadratic squareness of sleepers and alignment and gauge on the curves in the later stages. This greatly reduces the amount of construction machinery and personnel required for later alignment treatment, resulting in significant time and cost savings.

[0080] In summary, this invention changes the traditional ballast laying and track tamping construction sequence by first adjusting the fixed alignment before ballast laying and track tamping. It places track setting and alignment adjustment for small-radius curves before ballast laying and tamping. During track laying, sleepers are densely arranged at rail joints, and concrete supports are added next to the sleepers to counteract the bending stress of the rails, ensuring the accuracy of alignment and track elevation control for small-radius curves. After sleeper placement, rail laying and fastener installation are carried out, and struts are used to fix the sleepers at the rail ends. The rails are fixed with sleepers, and then bent into the rail bearing groove by construction machinery. Fasteners are then installed to secure the rails, preventing deformation at the rail ends due to excessive bending stress. After these steps, ballast sizing begins to ensure the alignment and elevation are achieved in one go. Finally, concrete supports are constructed at the ground anchor positions on the outside of the curve to ensure that the track will not deform due to external forces during operation after the track is laid. This effectively fixes the track alignment, ensures the stability of the line in later operation, and reduces the investment in later operation, maintenance, and upkeep.

[0081] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit and principles thereof should fall within the protection scope defined by the claims of the present invention.

Claims

1. Method for laying a small-radius-curve tramway with a jointed line with ballast track, characterized in that, It comprises the following steps: S1, construction preparation: measuring and checking the subgrade surface elevation, and setting out the line stakes and side stakes; S2, bottom ballast laying: measuring and setting out the outer edge line of the bottom ballast laying, calculating the height of the ballast needed to be laid for each section according to the loose laying coefficient, and then laying and compacting the bottom ballast; S3, placing sleepers: placing sleepers according to the measurement and setting out, taking the left side of the line and the outer strand of the curve as the basic track and aligning the basic track sleepers; spreading sleepers on the ballast, positioning according to the sleeper position in the track joint table, and fixing a sleeper every 3 meters on the small radius curve by using two ground anchors within the sleeper width range; and additionally arranging sleepers at the rail joint position on the small radius curve and fixing them with support rods; S4, installing rails and fasteners: after the track laying, the rail joint position on the small radius curve is controlled to the design value, and the fish tail clamp plate is connected; S5, laying ballast: gradually aligning the newly laid track; S6, measurement and review: reviewing the position of the track center line and curve elements in terms of plane and elevation, checking whether the rail gauge widening and curve super elevation meet the design requirements, and ensuring that the line is accurate and correct, checking whether the sleepers are aligned, whether the rail fasteners and joint clamps are correctly installed, and whether the bolts are tightened; S7, pier construction: after all the checks and reviews are correct, four areas of the size of the sleeper range are planed on the outside of the sleepers at the joint of the small radius curve outer strand, and the reinforced concrete support pier is constructed to rest on the end of the four sleepers.

2. The small-radius curve tramway jointed ballast track laying method according to claim 1, characterized in that, In step S2, the compacted ballast is 3-5 cm lower than the design elevation.

3. The small-radius curve tramway jointed ballast track laying method according to claim 1, characterized in that, In step S3, the distance between sleepers at the rail joint position on the small radius curve is 550 mm, 50≤R<100 meters of small radius curve has two support rods before and after the joint, R≥100 meters of small radius curve has one support rod before and after the joint, and ground anchors are arranged 1 meter away from both sides of the sleepers, the ends of the support rods are fixedly connected to the sleepers and the corresponding ground anchors, the direction of the support rods is in line with the sleepers, and the sleepers are aligned.

4. The small-radius curve tramway jointed ballast track laying method according to claim 1, characterized in that, The operation content of step S5 includes aligning the sleepers, supplementing and tightening the fasteners and clamps, straightening the track direction, filling the ballast under the sleepers at the bearing rail, eliminating the reverse super elevation and triangular pits, and the specific steps are as follows: Track straightening: straighten the line to the center line position, and the track center line deviation is less than 30 mm; Aligning sleepers: after straightening, align the inclined sleepers to make the sleeper spacing and deviation within 2 cm; Laying ballast: after the track laying is completed, evenly spread the ballast in the track by using machinery or manual work; Track lifting: use the hydraulic track lifting machine to lift each track at several points and pad with ballast, the lifting amount at a time should not exceed 15 cm, the track is lifted to the design elevation with an additional 10 mm of subsidence amount; the outer strand of the curve is lifted according to the specified super elevation, the high-low deviation of the track after lifting is ≤5 mm, and the left-right horizontal deviation is ≤5 mm; first check the rail surface elevation of one strand, and then adjust the rail surface elevation of the other strand according to the curve, and the rail surface elevation deviation is -30~+50 mm; Ballast filling: fill the ballast at the shoulder into the sleeper box after lifting. Tamping: Tamp the ballast within a 45cm range on the outer and inner sides of the rails, and tamping is strictly prohibited within a 60cm range in the middle of the sleepers; strengthen the tamping range below the rails, rail joints, and outer strands of curves; Track alignment: Correct the horizontal position of the track and make the center line of the track consistent with the center of the track; repair the track bed, replenish the ballast in the sleeper box, compact the side slope and top surface of the track bed and keep it stable; straighten the track, correct the hard bends of the rails to achieve a straight and smooth appearance from a distance, level small depressions when starting the track, and correct the horizontal level and vertical height of the rails; align the sleepers and tighten the fasteners. Tightening: Tighten the joint bolts daily to ensure a torque of over 500 N·m, and tighten the rail fasteners regularly, keeping the torque between 100 and 140 N·m.

5. The small-radius curve tramway jointed ballast track laying method according to claim 1, characterized in that, In step S7, the support is 2.5m long, 1m wide, and more than half the height from the top surface of the roadbed to the end face of the sleeper. A double-layered, bidirectional steel mesh is arranged inside the roadbed. The concrete support wraps around the prestressed steel bars of the positioned sleeper and fits tightly against the sleeper. The vertical steel bars are implanted into the roadbed. After the concrete strength reaches 100%, the support rods are removed.

6. The small-radius curve tramway jointed ballast track laying method according to claim 1, characterized in that, The track bed constructed using this method is a crushed stone track bed, and the rails are laid using a jointed track. The 59R2 grooved rail has a bottom width of 180mm and no bottom slope. The width of the rail bearing groove is 355mm, and the distance from the center line of the rail bearing groove on both sides to the center line of the sleeper is 734.625mm. Anchoring holes are set on both sides of the rail bearing groove. The rails used are 25m standard rails, and the fastening accessories are spring clip type I fasteners. The rail slope at the gauge baffle fastening position of the spring clip type I fastener is 1:10.

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