Structure for improving stress performance of CRTSII track slab post-cast strip

Abstract

The invention provides a structure for improving the stress performance of a CRTSII track slab post-cast strip, and belongs to the technical field of track slabs, the structure comprises a track slab, a base plate and a bridge which are distributed up and down, and a sliding layer is arranged between the base plate and the bridge; two post-cast strip tooth grooves are formed in the bottom of the bridge fixing end, a shear elastic assembly is arranged at the bottoms of the two post-cast strip tooth grooves and comprises two I-shaped steel structures, embedding grooves are formed in the two post-cast strip tooth grooves, and the top ends of the two I-shaped steel structures are embedded in the two embedding grooves correspondingly. The bottom ends of the two I-shaped steel structures are wrapped with elastic materials. According to the tooth socket structure, the contact area of the tooth socket structure and tooth socket concrete is increased, the acting force can be more uniformly transmitted to the tooth socket structure, the acting force can be more uniform through the elastic material, local stress concentration is avoided, the possibility that the tooth socket is damaged due to uneven stress is reduced, and the damage frequency is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of track slabs, and more particularly, relates to a structure for improving the stress-bearing performance of a post-cast strip of a CRTSII track slab. Background Art

[0002] With the development of high-speed railway construction in my country, the CRTSⅡ ballastless track system has become the track structure of major trunk railways in my country due to its high stability and low maintenance. It is mainly used in elevated bridge sections. To limit the sliding between the track structure base plate and the bridge, post-cast strip grooves are usually set at the fixed end of the bridge.

[0003] However, the CRTSⅡ track structure on the elevated bridge suffers from a high frequency of damage to the post-cast strip at the bridge end, primarily manifested in damage to the upper and lower grooves of the post-cast strip. Currently, the commonly used repair method for post-cast strip grooving damage is to chisel out the damaged concrete and re-cast it. However, this method only repairs the damaged concrete structure and does not improve the stress environment of the grooving. Therefore, a structure is needed that can improve the stress performance of the post-cast strip of the CRTSⅡ track slab and reduce the frequency of grooving damage. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a structure for improving the stress performance of the post-cast strip of the CRTSII track plate, so as to solve the technical problem in the prior art that the traditional track plate post-cast strip has a high damage frequency, which is mainly manifested in the destruction of the upper and lower teeth of the post-cast strip, and re-casting does not improve the stress environment of the teeth.

[0005] The purpose and efficacy of the structure of the present invention for improving the stress performance of the post-cast strip of the CRTSII track slab are achieved by the following specific technical means: A structure for improving the stress performance of a post-cast strip of a CRTSII track slab, comprising a track slab, a base plate and a bridge distributed vertically, wherein a sliding layer is provided between the base plate and the bridge; Two groups of post-cast strip grooves are provided at the bottom of the fixed end of the bridge, and shear elastic components are provided at the bottom of the two groups of post-cast strip grooves. The shear elastic components include two groups of I-shaped steel structures. Embedding grooves are opened in the two groups of post-cast strip grooves. The top ends of the two groups of I-shaped steel structures are respectively buried in the two groups of embedding grooves, and the bottom ends of the two groups of I-shaped steel structures are wrapped with elastic materials.

[0006] In a preferred embodiment, the shear elastic component further includes two sets of steel structure jackets, and the bottom ends of the two sets of I-shaped steel structures are respectively provided with two sets of steel structure jackets; The elastic material is located between the I-shaped steel structure and the steel structure outer shell.

[0007] In a preferred embodiment, the bottoms of the two groups of steel structure jackets are connected to shear bars, and the bottoms of the shear bars are welded to the bridge deck steel bars as a whole.

[0008] In a preferred embodiment, the length of the I-shaped steel structure is consistent with the width of the base plate; The elastic material can be rubber, polyurethane, polyethylene or similar materials.

[0009] Compared with the prior art, the present invention has the following beneficial effects: 1. The setting of shear elastic components improves the stress-bearing performance of the track slab post-cast strip. The tops of the two sets of I-shaped steel structures are buried in the buried groove. Through elastic deformation, the force can be more evenly transmitted to the tooth groove structure, avoiding local stress concentration. The elastic material filled between the I-shaped steel structure and the steel structure jacket can also buffer the longitudinal force and displacement generated by the track structure under the action of train load and temperature changes, allowing the track base plate and the top surface of the bridge to move relative to each other within a certain range, reducing the stress on the tooth groove of the post-cast strip, reducing the possibility of damage to the tooth groove due to uneven force, and reducing the damage frequency. The bottom of the steel structure jacket is connected to the shear reinforcement, and the shear reinforcement is welded to the bridge deck steel bar as a whole. This connection method closely combines the shear elastic component with the bridge structure to form a stable force system.

[0010] 2. The length of the I-shaped steel structure is consistent with the width of the track plate, ensuring that the force is evenly distributed within the width of the track plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the structure after assembly of a structure for improving the stress performance of the post-cast strip of the CRTSII track slab according to the present invention; Figure 2 This is a schematic diagram of the structure after expansion of a structure for improving the stress performance of the post-cast strip of the CRTSII track slab according to the present invention; Figure 3 This is a left view of a structure for improving the stress-bearing performance of the post-cast strip of a CRTSII track slab according to the present invention; Figure 4 yes Figure 3 Cross-sectional view of AA; Figure 5 yes Figure 4 A magnified schematic diagram of area a in the middle; Figure 6 This is a schematic structural diagram of the assembled shear elastic components in a structure for improving the stress-bearing performance of the post-cast strip of a CRTSII track slab according to the present invention; Figure 7 yes Figure 6 Schematic diagram of the structure after decomposition.

[0012] In the figure, the correspondence between the component names and the drawing numbers is: 11, base plate; 12, bridge; 13, sliding layer; 14, post-cast strip groove; 21, I-shaped steel structure; 22, buried groove; 23, steel structure jacket; 24, elastic material; 25, shear reinforcement; 26, bridge deck reinforcement. DETAILED DESCRIPTION

[0013] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the technical solutions of the present invention, but are not intended to limit the scope of protection of the present invention.

[0014] Example: As attached Figures 1 to 7 As shown: The present invention provides a structure for improving the stress performance of the post-cast strip of the CRTSII track plate, comprising a track plate, a base plate 11 and a bridge 12 arranged in sequence, a sliding layer 13 being arranged between the base plate 11 and the bridge 12, and the sliding layer 13 adopts a composite structure of geotextile-film-geotextile, the geotextile having good flexibility and puncture resistance, and the film having a low friction coefficient; this structure effectively reduces the friction between the base plate 11 and the top surface of the bridge 12, so that the longitudinal force generated by the base plate 11 under the action of train load and temperature change can be transmitted through the post-cast strip tooth groove 14, which plays a fundamental role in improving the stress environment of the post-cast strip tooth groove 14; the bottom of the bridge 12 Two groups of post-cast strip tooth grooves 14 are set, which are the parts of the track structure that bear longitudinal force and constrain bridge displacement. Shear elastic components are set at the bottom of the two groups of post-cast strip tooth grooves 14. The shear elastic components include two groups of I-shaped steel structures 21. Embedding grooves 22 are opened in the two groups of post-cast strip tooth grooves 14. The top ends of the two groups of I-shaped steel structures 21 are respectively buried in the two groups of buried grooves 22. After the top ends of the I-shaped steel structures 21 are buried in the buried grooves 22, the contact area between them and the tooth groove concrete is increased. When the applied force remains unchanged, the contact area is increased and the pressure per unit area is reduced, so that the applied force is more evenly transmitted to the tooth groove structure, avoiding the occurrence of local stress concentration.

[0015] Please refer to Figure 5 and Figure 7 As shown, the shear elastic component also includes two groups of steel structure jackets 23. The bottom ends of the two groups of I-shaped steel structures 21 are respectively connected to the two groups of steel structure jackets 23. Elastic material 24 is filled between the I-shaped steel structure 21 and the steel structure jacket 23. During the operation of the train, the track structure will vibrate and displace due to the train load. At the same time, changes in ambient temperature will also cause the track structure to expand and contract. The elastic material 24 can buffer these longitudinal forces and displacements by virtue of its own elastic properties; it allows the track base plate 11 and the top surface of the bridge 12 to move relative to each other within a certain range, relieves the stress on the tooth groove 14 of the post-cast strip, reduces the possibility of damage to the tooth groove due to uneven force, and thus reduces the frequency of damage.

[0016] Please refer to Figure 6 and Figure 7 As shown, the bottoms of the two sets of steel structure jackets 23 are connected to the shear bars 25, and the bottoms of the shear bars 25 are welded to the bridge deck steel bars 26 as a whole. Welding can form a reliable metal connection. This connection method firmly combines the shear elastic components with the bridge structure to form a stable force system. When the track structure is subjected to various forces generated by train loads and environmental effects, the system can cooperate to resist and ensure the stability of the structure.

[0017] The length of the I-shaped steel structure 21 matches the width of the base plate 11. This dimensional match ensures that the force is evenly distributed across the width of the base plate 11. The elastic material 24 can be made of rubber, polyurethane, polyethylene, or similar materials. Rubber has high elasticity and good wear resistance; polyurethane has high strength, good elasticity, and is resistant to aging; polyethylene has excellent chemical stability and self-lubrication. These materials all meet the elasticity and durability requirements of shear elastic components.

[0018] The specific usage and function of this embodiment: When the post-cast strip at the end of the CRTSⅡ track plate bridge of the viaduct is damaged, the damaged part must be processed first. First, use equipment to chisel out the concrete of the base plate 11 at the bottom of the damaged and failed track plate, and continue to chisel the bridge deck concrete at the bridge 12 tooth groove. The chiseling depth is not less than the depth required for the bottom of the I-shaped steel structure 21 in the shear elastic component to be buried. Remove the concrete debris generated during the chiseling process to fully expose the original shear reinforcement 25 and the bridge deck steel bars 26; align the top ends of the two groups of I-shaped steel structures 21 and bury them in the embedding grooves 22 in the two groups of post-cast strip tooth grooves 14. The length of the I-shaped steel structure 21 is consistent with the width of the base plate 11, ensuring that the force is evenly distributed within the width of the base plate 11. Next, the steel structure jacket 23 is connected to the bottom end of the I-shaped steel structure 21, and an elastic material 24 is filled between the two. The elastic material 24 can be selected from one of rubber, polyurethane, or polyethylene materials. Subsequently, the bottom of the steel structure jacket 23 is connected to the shear reinforcement 25, and the bottom of the shear reinforcement 25 is firmly welded to the bridge deck reinforcement 26 through a welding process. After completing the above steps, the bridge deck concrete is cast to make the repaired bridge deck level with the bottom of the steel structure jacket 23. After the bridge deck concrete solidifies, a sliding layer 13 is laid on the bridge deck. The sliding layer adopts a composite structure of geotextile-film-geotextile, which can effectively reduce the friction between the track plate and the top surface of the bridge 12. Finally, concrete is cast to repair the track plate to complete the installation of the entire structure.

[0019] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A structure for improving the mechanical properties of the post-cast strip of a CRTSII track slab, characterized by: It comprises a track plate, a base plate (11) and a bridge (12) distributed vertically, wherein a sliding layer (13) is provided between the base plate (11) and the bridge (12); Two groups of post-cast strip tooth grooves (14) are provided at the bottom of the fixed end of the bridge (12), and shear elastic components are provided at the bottom of the two groups of post-cast strip tooth grooves (14). The shear elastic components include two groups of I-shaped steel structures (21), and buried grooves (22) are provided in the two groups of post-cast strip tooth grooves (14). The top ends of the two groups of I-shaped steel structures (21) are respectively buried in the two groups of buried grooves (22), and the bottom ends of the two groups of I-shaped steel structures (21) are wrapped with elastic materials (24).

2. The structure for improving the mechanical properties of the post-cast strip of a CRTSII track slab according to claim 1, characterized in that: The shear elastic component further comprises two sets of steel structure outer sleeves (23), and the bottom ends of the two sets of I-shaped steel structures (21) are respectively provided with two sets of steel structure outer sleeves (23); The elastic material (24) is located between the I-shaped steel structure (21) and the steel structure jacket (23).

3. The structure for improving the mechanical properties of the post-cast strip of CRTSII track slab according to claim 2, characterized in that: The bottoms of the two groups of steel structure jackets (23) are connected to the shear reinforcement (25), and the bottoms of the shear reinforcement (25) are welded to the bridge deck reinforcement (26) as a whole.

4. The structure for improving the mechanical properties of the post-cast strip of a CRTSII track slab according to claim 3, characterized in that: The length of the I-shaped steel structure (21) is consistent with the width of the base plate (11); The elastic material (24) may be rubber, polyurethane, polyethylene or similar materials.

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