A kind of elastic long sleeper track bed for urban rail transit

Abstract

The present invention discloses an elastic long sleeper ballast for urban rail transit, with double-sided drainage ditches arranged on both sides of the ballast, and a drainage pipe buried inside the ballast in the middle of the ballast. Vibration-damping pads are installed on both sides of the bottom of the prestressed concrete long sleeper, a low-rigidity pad is installed in the middle of the bottom of the long sleeper, and isolation pads are installed around the sides of the long sleeper; an anti-debris filter block structure is arranged on both sides of the middle of the long sleeper to prevent debris from entering, and the contact range between the top of the drainage pipe and the bottom of the long sleeper and the contact range between the top of the drainage pipe and the bottom of the anti-debris filter block is cut off. Inspection wells are arranged at intervals in the center of the ballast, and the inspection wells are connected to the buried drainage pipes. The present invention can solve the technical problems of the poor flatness and patency of the evacuation surface of the traditional elastic long sleeper ballast with a central open ditch, the complex ditch forming template, the smoothness and stability of the track structure being greatly affected by construction factors, the weakening of the overall strength of the ballast structure, and the impact of local mold running on the vibration reduction performance.

Description

Technical Field

[0001] The invention relates to a technology for improving urban rail transit facilities. Background Art

[0002] The traditional elastic prestressed concrete long sleeper structure is composed of a prestressed concrete long sleeper, isolation rubber boots on both sides, and vibration damping pads inside the isolation rubber boots. The traditional center open ditch elastic long sleeper ballast structure is equipped with a center open ditch of a certain width in the center of the ballast. Under this ballast structure system, the prestressed concrete long sleeper relies on the isolation rubber boots and vibration damping pads on both sides to contact the ballast, which plays a role in supporting the upper structure and reducing vibration; the middle part of the prestressed concrete long sleeper is suspended in the air, which can avoid the middle area of ​​the prestressed concrete long sleeper from being subjected to a large negative bending moment, ensuring the structural safety of the prestressed concrete long sleeper itself; the accumulated water inside the isolation rubber boot can be discharged into the center open ditch through the lateral opening of the isolation rubber boot structure. The elastic long sleeper ballast structures currently used in urban rail transit projects in China all adopt the above structural system.

[0003] The main deficiencies of the traditional central open ditch elastic long sleeper track bed structure system are:

[0004] First, the setting of the central open ditch affects the evacuation function of the roadbed. The central open ditch of the roadbed is a continuous groove structure of a certain depth along the direction of the line on the roadbed surface. Coupled with the transversely distributed prestressed concrete long sleeper structure, it affects the operational patrol and safe evacuation channel functions realized by the roadbed surface, posing a safety risk;

[0005] Second, the track structure construction process is relatively complicated, which is not conducive to the construction progress. The casting of the central open ditch requires the cooperation of two sets of combined ditch templates (divided into the lower template of the prestressed concrete long sleeper and the middle template of the prestressed concrete long sleeper). The process is relatively complicated, the construction difficulty is relatively large, the project progress and the construction period are not well coordinated, and the construction period risk is relatively large;

[0006] Third, it is relatively difficult to control the overall stability and smoothness of the track structure. The isolation rubber boots and the prestressed concrete long sleepers need to be assembled on site. Affected by the production process, assembly process, and on-site concrete ballast pouring and extrusion, there is a possibility of large uneven gaps between the isolation rubber boots and the prestressed concrete long sleepers, which will directly affect the stability and smoothness of the ballast structure during the later operation process;

[0007] Fourth, the central open ditch has a certain weakening effect on the overall strength of the ballast structure;

[0008] Fifth, when concrete overflow occurs, there is a risk of reducing the local vibration reduction capacity, and subsequent control and transformation are relatively difficult. Summary of the invention

[0009] The purpose of the present invention is to provide an elastic long sleeper ballast bed for urban rail transit, so as to solve the technical problems of the traditional elastic long sleeper ballast bed with central open ditch, such as poor flatness and patency of the evacuation surface, complex ditch forming template, the smoothness and stability of the track structure being greatly affected by construction factors, the overall strength of the ballast bed structure being weakened, and local mold running affecting the vibration reduction performance.

[0010] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0011] An elastic long sleeper ballast for urban rail transit, comprising a prestressed concrete long sleeper, an isolation pad, a vibration-damping pad, a low-rigidity pad, an embedded drainage pipe, an anti-debris filter block, an inspection well and a double-sided ditch ballast; the isolation pad, the vibration-damping pad and the low-rigidity pad are prefabricated on the prestressed concrete long sleeper to form an integral elastic prestressed concrete long sleeper system; double-sided drainage ditches are arranged on both sides of the ballast, and an embedded drainage pipe structure embedded in the ballast is arranged in the middle of the ballast; vibration-damping pads are installed on both sides of the bottom of the prestressed concrete long sleeper, a low-rigidity pad is installed in the middle of the bottom of the prestressed concrete long sleeper, and the prestressed concrete long sleeper is installed in the middle of the bottom of the prestressed concrete long sleeper. Isolation pads are installed around the sides of the sleeper; anti-debris filter block structures are set on both sides of the middle of the long prestressed concrete sleeper to prevent the entry of debris; the contact range between the top of the buried drainage pipe and the bottom of the long prestressed concrete sleeper and the bottom of the anti-debris filter block are cut off, leaving a gap that can ensure that a small amount of accumulated water between the contact surface of the long prestressed concrete sleeper structure and the ballast structure can flow downward into the buried drainage pipe, while preventing foreign objects such as iron filings, oil stains, and stones from entering the buried drainage pipe; inspection wells are set at regular intervals in the center of the ballast bed to check the status of the buried drainage pipe and to clear and repair it, and the inspection wells are connected to the buried drainage pipe.

[0012] The advantages of the present invention are as follows:

[0013] The present invention can effectively improve the flatness and smoothness of the surface of the traditional central open ditch elastic long sleeper ballast structure as an evacuation passage through the above technical measures, significantly improve the safety and comfort of personnel walking, simplify the construction process, improve the construction progress, improve the ability to maintain the smoothness and stability of the track structure, improve the overall strength of the ballast, increase the factory prefabrication rate of track components, reduce the impact of on-site human factors, thereby ensuring the quality of the project, extending the service life of the ballast, effectively ensuring the vibration reduction capacity, and facilitating the partial replacement of failed prestressed concrete long sleepers, etc.

[0014] The central open ditch structure set in the elastic long pillow ballast of the central open ditch was cancelled, which effectively ensured the flatness and smoothness of the evacuation surface of the ballast;

[0015] The two sets of templates for casting the central open ditch of the elastic long pillow ballast of the central open ditch were reduced, which simplified the construction process, accelerated the construction speed and effectively guaranteed the construction period;

[0016] The combined use of drainage ditches on both sides of the ballast and buried drainage pipes effectively ensures the overall drainage capacity of the ballast structure; the drainage ditches on both sides are mainly responsible for the traditional drainage of the ballast structure; the buried drainage pipes, combined with anti-debris filter blocks, inspection wells and other structures, are mainly responsible for collecting and draining a small amount of accumulated water between the prestressed concrete long sleeper structure and the contact surface of the ballast, ensuring the working environment of the elastic prestressed concrete long sleeper system;

[0017] The low-rigidity pad can effectively prevent concrete from entering the bottom of the prestressed concrete long sleeper during the roadbed pouring, thereby avoiding excessive negative bending moment in the middle of the prestressed concrete long sleeper and ensuring the safety of the prestressed concrete long sleeper;

[0018] The isolation pad fits tightly with the prestressed concrete long sleeper, which can effectively solve the problem of separation between the isolation rubber boot and the prestressed concrete long sleeper in the traditional ballast structure, thereby improving the smoothness and stability of the ballast structure;

[0019] The vibration-damping pad fits tightly with the prestressed concrete long sleeper, which can effectively prevent debris from entering between the prestressed concrete long sleeper and the vibration-damping pad; the vibration-damping pad, the isolation pad and the low-rigidity pad fit tightly with each other, and the joints are sealed, which can effectively avoid the limitation of the vertical freedom of the prestressed concrete long sleeper structure caused by concrete running out of the mold when pouring the center open ditch of the traditional center open ditch elastic long sleeper ballast bed, resulting in a certain loss of vibration-damping capacity, thereby ensuring the working performance of the vibration-damping pad and the vertical freedom of the prestressed concrete long sleeper, so that the vibration-damping function of the ballast bed can be stably exerted;

[0020] The vibration-damping pads, isolation pads and low-rigidity pads are prefabricated on the prestressed concrete long sleepers, which effectively ensures the product quality, reduces the influence of on-site manual factors, and is beneficial to improving the durability, stability and service life of the track bed;

[0021] When replacing failed prestressed concrete long sleepers, the prestressed concrete long sleepers, isolation pads, vibration-damping pads and low-rigidity pads form a whole, which can be hoisted out and replaced as a whole, without the need for destructive operations on the ballast structure, which is conducive to later maintenance and repair;

[0022] The elimination of the central open ditch increases the integrity of the ballast section and significantly improves the overall strength of the ballast structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of an assembly embodiment of the elastic prestressed concrete long sleeper system of the present invention.

[0024] Figure 2 It is a schematic diagram of an exemplary embodiment of the three-dimensional structure assembly of the present invention.

[0025] Figure 3 It is a schematic diagram of an embodiment of the track structure of the present invention.

[0026] Figure 4 It is a schematic diagram of replacing a failed prestressed concrete long sleeper according to the present invention.

[0027] Numbers in the figure: 1. Prestressed concrete long sleeper; 2. Vibration-damping pad; 3. Isolation pad; 4. Low-rigidity pad; 5. Embedded drainage pipe; 6. Double-sided ditch; 7. Inspection well; 8. Anti-debris filter block; 9. Push aside the rails; 10. Lift out the failed elastic long sleeper; 11. Put in a new elastic long sleeper; 12. Failed sleeper; 13. New sleeper. DETAILED DESCRIPTION

[0028] The specific embodiments of the present invention are described as follows in conjunction with the accompanying drawings: Figure 1 , 2 As shown in Figure 3, an elastic long sleeper ballast for urban rail transit is composed of a prestressed concrete long sleeper, an isolation pad, a vibration reduction pad, a low-rigidity pad, an embedded drainage pipe, an anti-debris filter block, a manhole, and a cast-in-place concrete double-sided ditch ballast. The present invention cancels the central open ditch structure on the surface of the traditional central open ditch elastic long sleeper ballast structure, and double-sided drainage ditches are set on both sides of the ballast to undertake the drainage task of the original track structure central open drainage ditch, ensuring that the drainage capacity is not reduced.

[0029] An embedded drainage pipe structure is set in the middle of the ballast bed to drain a small amount of water that has seeped into the contact surface between the long prestressed concrete sleepers and the ballast bed. The embedded drainage pipe is required to be tied and fixed to the rail.

[0030] Vibration-damping pads are installed on both sides of the bottom of the prestressed concrete long sleeper to ensure the vibration-damping capacity of the ballast structure; (The vibration-damping pads are required to be installed during the prefabrication of the prestressed concrete long sleeper to ensure the quality of the combination of the two) A low-rigidity pad is installed in the middle of the bottom of the prestressed concrete long sleeper to prevent the middle part of the prestressed concrete long sleeper from being subjected to excessive negative bending moment when the train passes, thereby ensuring the safety of the prestressed concrete long sleeper structure; (The low-rigidity pad is required to be installed during the prefabrication of the prestressed concrete long sleeper to ensure the quality of the combination of the two) Isolation pads are set around the sides of the prestressed concrete long sleeper to avoid contact between the ballast concrete and the prestressed concrete long sleeper, thereby ensuring the vertical freedom of the prestressed concrete long sleeper structure and realizing the vibration-damping function. The isolation pads are fixed on the four sides of the prestressed concrete long sleeper, which can effectively solve the problem of excessive gap between the isolation rubber boot and the prestressed concrete long sleeper in the traditional center open ditch elastic long sleeper ballast structure; (The isolation pad is required to be installed during the prefabrication of the prestressed concrete long sleeper to ensure the quality of the combination of the two)

[0031] On both sides of the middle of the prestressed concrete long sleeper, an anti-debris filter block structure is set to prevent debris from entering. The contact range between the top of the buried drainage pipe and the bottom of the prestressed concrete long sleeper and the bottom of the anti-debris filter block is cut off. The cut range of the buried drainage pipe matches the bottom of the prestressed concrete long sleeper and the size of the anti-debris filter block structure on both sides, so as to ensure that a small amount of accumulated water between the contact surface of the prestressed concrete long sleeper structure and the ballast structure can flow downward into the buried drainage pipe, and at the same time, foreign matter such as iron filings, oil stains, and stones are prevented from entering the buried drainage pipe, so as to ensure the normal working environment of components such as vibration damping pads;

[0032] The contact part between the bottom of the prestressed concrete long sleeper and the cut edge of the buried drainage pipe, as well as the contact part between the debris filter block structure and the cut edge of the buried drainage pipe, should be sealed to prevent concrete from entering the buried drainage pipe when pouring the ballast bed;

[0033] Inspection wells are set up at regular intervals in the center of the roadbed to check the status of the buried drainage pipes and to clear and repair them.

[0034] See also Figure 4 As shown in the figure. The track bed is easy to maintain and can be used to replace the failed prestressed concrete long sleepers. The prestressed concrete long sleepers are integrated with the isolation pads, vibration damping pads and low-rigidity pads, and can be hoisted out and replaced as a whole without destructive operations on the track bed structure. The replacement speed is fast, the impact on line restoration is small, and the operation risk is low.

[0035] The construction process of the present invention:

[0036] When producing prestressed concrete long sleepers, isolation pads, vibration-damping pads and low-rigidity pads are prefabricated on the prestressed concrete long sleepers at the same time to form a whole, forming an elastic prestressed concrete long sleeper system. This effectively ensures the manufacturing accuracy and installation reliability of the main rail components; (Compared with traditional elastic prestressed concrete long sleepers: prestressed concrete long sleepers, isolation rubber boots, and vibration-damping pads are produced separately and need to be manually assembled at the construction site. The assembly accuracy, firmness, and tightness are greatly affected by human factors, and there are risks such as separation between the prestressed concrete long sleepers and the isolation rubber boots, and poor sealing of the tape.)

[0037] The track construction method is used to tie elastic prestressed concrete long sleepers, embedded drainage pipes, wooden blocks (of the same size as anti-debris filter blocks, which are replaced with anti-debris filter blocks after the ballast bed is poured), inspection wells, rails, and fasteners into track rows. The site is positioned according to the actual project requirements, and then the ballast bed concrete is poured. The two sets of ditch templates required to form the center open ditch structure of the traditional center open ditch elastic long sleeper ballast are eliminated, which significantly simplifies the construction process and improves the construction progress; (Compared with the traditional center open ditch elastic long sleeper ballast: In addition to the traditional construction process of the traditional center open ditch elastic long sleeper ballast using the rail row method, it is also necessary to focus on the assembly of the ditch template for forming the center open ditch. The templates of the center open ditch are divided into two sets, which are located between the prestressed concrete long sleepers and at the bottom of the prestressed concrete long sleepers. They are positioned by connectors and wedge-shaped wooden blocks. After checking that they are correct, the ballast bed concrete can be poured. During the pouring process, close attention should be paid to the concrete forming situation in the ditch template range. The construction process is relatively cumbersome and the construction speed is slow.)

[0038] The ballast structure formed by the scheme of the present invention has a smooth surface, eliminates the obstruction formed by the central open ditch and the transverse sleepers of the traditional central open ditch elastic long sleeper ballast structure, makes the ballast surface a passage for daily patrol and evacuation in emergency situations, and significantly improves the comfort of patrol work and the safety during evacuation; (Compared with the traditional central open ditch elastic long sleeper ballast: the traditional central open ditch elastic long sleeper ballast has a longitudinally distributed ditch structure of a certain width and a certain depth in the middle of the ballast, and the ditch structure is also separated by the vertically distributed prestressed concrete long sleepers, which increases the unevenness of the ballast surface, is not conducive to walking and evacuation, and has safety risks.)

[0039] Traditional double-sided ditches are set on both sides of the ballast, and the drainage capacity is equivalent to that of the central open ditch; the buried drainage pipe is cut in the range of contact with the bottom of the prestressed concrete long sleeper and the anti-debris filter block, which can collect a small amount of accumulated water between the contact surface of the prestressed concrete long sleeper and the concrete ballast, and directly flow downward into the buried drainage pipe and be discharged along the longitudinal direction of the line; an inspection well is set every 10-15m, and the inspection well is connected to the buried drainage pipe for checking the status of the buried drainage pipe and clearing and repairing it.

[0040] See also Figure 4 As shown in the figure, when the failed prestressed concrete long sleeper needs to be replaced, first loosen the fastener spring strips within a certain length range according to the maintenance requirements, and push away the rails, and use a small gantry crane to lift the failed prestressed concrete long sleeper (including various pads) out of the original ballast structure. Then put the new failed prestressed concrete long sleeper (including various pads) back in place, push back the rails, install the fastener spring strips, and fine-tune the track geometry to complete the replacement of the prestressed concrete long sleeper.

Claims

1. A construction method for an elastic long sleeper ballast bed for urban rail transit, characterized in that: The elastic long sleeper ballast bed is composed of prestressed concrete long sleepers, isolation pads, vibration reduction pads, low-rigidity pads, embedded drainage pipes, debris-proof filter blocks, inspection wells and double-sided water ditch ballast beds; Isolation pads, vibration-damping pads and low-rigidity pads are prefabricated on prestressed concrete long sleepers to form an integrated elastic prestressed concrete long sleeper system; double-sided drainage ditches are set on both sides of the ballast, and an embedded drainage pipe structure buried inside the ballast is set in the middle of the ballast; vibration-damping pads are installed on both sides of the bottom of the prestressed concrete long sleeper, and a low-rigidity pad is installed in the middle of the bottom of the prestressed concrete long sleeper to prevent the middle of the prestressed concrete long sleeper from being subjected to excessive negative bending moment when the train passes by, and isolation pads are installed around the sides of the prestressed concrete long sleeper; Anti-debris filter block structures are set on both sides of the middle of the prestressed concrete long sleeper to prevent the entry of debris. The contact range between the top of the buried drainage pipe and the bottom of the prestressed concrete long sleeper and the bottom of the anti-debris filter block are cut off, which can ensure that a small amount of accumulated water between the contact surface of the prestressed concrete long sleeper structure and the ballast structure can flow downward into the buried drainage pipe, and prevent iron filings, oil stains and stones from entering the buried drainage pipe; inspection wells for checking the status of the buried drainage pipe and clearing and repairing it are set at intervals in the center of the ballast bed. The inspection wells are connected to the buried drainage pipe. The construction method of the elastic long sleeper ballast for urban rail transit includes: when producing the prestressed concrete long sleeper, prefabricating the isolation pad, the vibration reduction pad and the low-rigidity pad on the prestressed concrete long sleeper to form a whole, thereby forming an elastic prestressed concrete long sleeper system; The track construction method is used for construction. The elastic prestressed concrete long sleepers are tied with embedded drainage pipes, wood blocks, inspection wells, rails and fasteners to form track rows. The track rows are positioned on site according to the actual project requirements, and then the track bed concrete is poured. Traditional double-sided ditches are set on both sides of the ballast, and the drainage capacity is equivalent to that of the central open ditch; the buried drainage pipe is cut in the range of contact with the bottom of the prestressed concrete long sleeper and the anti-debris filter block, which can collect a small amount of accumulated water between the contact surface of the prestressed concrete long sleeper and the concrete ballast, and directly flow downward into the buried drainage pipe and be discharged along the longitudinal direction of the line; an inspection well is set every 10-15m, and the inspection well is connected to the buried drainage pipe for checking the status of the buried drainage pipe and clearing and repairing it.

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