Concrete frog structure and manufacturing method

Abstract

The application discloses a concrete frog structure and a manufacturing method thereof, and relates to the technical field of track transportation, so as to solve the problems of high maintenance cost and long time consumption after the damage of a pre-embedded part. The concrete frog structure comprises a concrete sleeper body and a frog bolt, and a bolt hole is formed in the concrete sleeper body; the bolt hole comprises an upper hole section, a middle hole section and a lower hole section which are connected in sequence from top to bottom; the cross section of the upper hole section is a first rectangle; the bolt head of the frog bolt is a second rectangle in cross section, the length of the second rectangle is smaller than the length of the first rectangle and larger than the width of the first rectangle, and the width of the second rectangle is smaller than the width of the first rectangle; a rotation stopping structure is arranged in the middle hole section and is integrally formed, and is used for limiting the rotation of the bolt head of the frog bolt in the horizontal direction. The concrete frog structure and the manufacturing method thereof provided by the application are used for abandoning the traditional pre-embedded sleeve or iron seat, and improving the maintenance efficiency, the maintenance cost and the availability of the railway line.

Description

Technical Field

[0001] This invention relates to the field of rail transit technology, and in particular to a concrete turnout sleeper structure and its manufacturing method. Background Technology

[0002] Prestressed concrete turnout sleepers are one of the important pieces of equipment in railways. Currently, concrete turnout sleepers mainly adopt two structural forms: pre-embedded sleeve type and pre-embedded iron base type. Both of these structures belong to the pre-embedded design, and the core components (sleeves or iron bases) used for connection and fixation must be precisely fixed in the designated positions within the sleeper mold before concrete pouring.

[0003] However, in the current situation where existing concrete turnout sleepers suffer damage to the embedded parts used for connection and fixation (such as corrosion, cracking, thread failure, or misalignment), the replacement and repair process is extremely complex, time-consuming, and labor-intensive. The construction is difficult, the procedures are intricate, the time is long, and the costs are high. In particular, the newly filled repair material requires sufficient curing time (usually several hours to several days), during which time the sleepers cannot bear train loads, severely restricting the normal operational efficiency of the line. Therefore, damage to the embedded parts used for connection and fixation not only results in high repair costs and long repair times, but also poses a significant challenge to the availability and ease of maintenance of railway lines. Summary of the Invention

[0004] The purpose of this invention is to provide a concrete turnout sleeper structure and manufacturing method, which eliminates the need for traditional pre-embedded sleeves or iron seats, thereby improving maintenance efficiency, maintenance costs, and the availability of railway lines.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a concrete turnout sleeper structure comprising a concrete sleeper body and turnout sleeper bolts. The concrete sleeper body has a bolt channel extending from top to bottom. The bolt channel comprises, from top to bottom, a connected upper section, a middle section, and a lower section. The upper section has a first rectangular cross-section. Along the extension direction of the bolt channel, the projection of the middle section on the horizontal plane completely covers the projection of the upper section. The bolt head of the turnout sleeper bolt has a second rectangular cross-section, the length of which is less than the length of the first rectangle but greater than the width of the first rectangle, and the width of the second rectangle is less than the width of the first rectangle. An integrally formed anti-rotation structure is provided within the middle section to restrict the rotation of the bolt head of the turnout sleeper bolt in the horizontal direction.

[0006] During installation, the bolt head of the turnout bolster is parallel to the length of the first rectangle, allowing it to pass downward through the upper hole section and into the middle hole section. When the turnout bolster is rotated, the bolt head abuts against the anti-rotation structure, thereby limiting its positioning in the horizontal direction.

[0007] Compared to existing technologies, the concrete turnout sleeper structure provided by this invention features a first rectangular cross-section in the upper section and a keyed structure with a second rectangular cross-section for the bolt head. The length and width of the second rectangle are both less than the length and width of the first rectangle. Therefore, when the bolt head is parallel to the length of the first rectangle, it can pass through the upper section and enter the middle section. After the turnout sleeper bolt rotates a certain angle, the first and second rectangles intersect, preventing the bolt head from protruding from the upper section. This prevents the bolt from rotating to a position where the long side of the bolt head is nearly parallel to the first rectangle, thus confining it within the middle section and allowing it to pass through, rotate, and lock into place. Replacement is achieved simply by rotating the bolt in the opposite direction until the bolt head's length is parallel to the first rectangle, allowing it to be removed from the upper section. A new turnout sleeper bolt can then be installed onto the concrete sleeper body. No pre-embedded bolts or sleeves are required, eliminating the complex procedures of precise positioning and fixing of pre-embedded parts before pouring, and simplifying the turnout sleeper manufacturing process. The turnout sleeper bolts and concrete sleeper body are designed separately, so the replacement process does not require disassembling a large number of rail components, removing the entire concrete turnout sleeper structure, drilling and chiseling away the concrete sleeper body, or waiting for the new pouring material to cure. This simplifies the originally complex and time-consuming maintenance work into a simple bolt-level quick disassembly and assembly operation, greatly reducing construction difficulty and cost, thereby improving maintenance efficiency, maintenance costs, and the availability of railway lines.

[0008] For example, when the bolt head of the turnout sleeper bolt enters the middle hole section and rotates 90°, the first rectangle and the second rectangle are orthogonally distributed. Since the length of the second rectangle is greater than the width of the first rectangle, the turnout sleeper bolt is prevented from protruding from the upper hole section.

[0009] In some possible implementations, the anti-rotation structure includes two inwardly protruding limiting bosses integrally formed at two corners symmetrical to the diagonal of the first rectangle within the central hole section. The inner surfaces of the limiting bosses constitute anti-rotation walls. The two limiting bosses are located at two corners symmetrical to the diagonal of the first rectangle, and their inner surfaces each form an anti-rotation wall. Each long side wall of the bolt head abuts against one of the anti-rotation walls, thereby limiting positioning in the horizontal direction. This achieves effective anti-rotation without pre-embedding, ensuring precise positioning of the turnout bolt during installation and preventing the turnout bolt from rotating to a position where the long side of the bolt head is nearly parallel to the first rectangle, thus preventing the turnout bolt from sliding out of the upper hole section during operation. During installation, the bolt head of the turnout bolt, with its length direction parallel to the length direction of the first rectangle, passes downward through the upper hole section into the central hole section. When the turnout bolt rotates a certain angle, the long side wall of the bolt head abuts against the anti-rotation wall, which serves to limit the positioning of the bolt head in the horizontal direction.

[0010] For example, the anti-rotation wall can be perpendicular or nearly perpendicular to the long side of the first rectangle. After the bolt head of the turnout bolt enters the middle hole section, it can rotate 90° first. At this time, the long side of the bolt head of the turnout bolt abuts against the anti-rotation wall, and the first rectangle and the second rectangle are orthogonally distributed, thereby preventing the turnout bolt from protruding from the upper hole section.

[0011] In some possible implementations, the width of the cross-section of the upper hole is 1.05-1.2 times the width of the bolt head, and its length is 1.1-1.3 times the length of the bolt head.

[0012] In some possible implementations, the cross-section of the lower hole is circular, and its diameter is smaller than the length of the second rectangle; In some other possible implementations, the cross-section of the lower hole section is a third rectangle, the length of which is less than the length of the second rectangle; In some other possible embodiments, the cross-sectional shape of the lower hole segment is the same as that of the middle hole segment, and the cross-sectional shape of the lower hole segment is smaller than that of the middle hole segment. Along the length direction of the first rectangle, the length of the cross-sectional shape of the lower hole segment is smaller than the length of the second rectangle, and along the width direction of the first rectangle, the width of the cross-sectional shape of the lower hole segment is smaller than the width of the second rectangle.

[0013] In some possible implementations, the width of the cross-section of the lower hole section along the width direction of the first rectangle is 0.7-0.9 times the width of the bolt head, and the length of the cross-section of the lower hole section along the length direction of the first rectangle is 0.7-0.9 times the length of the bolt head.

[0014] In some possible implementations, the concrete turnout sleeper structure also includes an elastic element disposed within the middle bore section and located between the end face of the upper bore section facing the middle bore section and the bolt head; the top surface of the elastic element is connected to the end face of the upper bore section facing the middle bore section.

[0015] In some possible implementations, the top surface of the concrete pillow is provided with a mounting groove, and the bottom wall of the mounting groove is provided with an inlet for the upper hole section. The concrete turnout sleeper structure also includes: Rubber pads and iron pads are arranged sequentially from top to bottom in the mounting grooves; The fastening system, installed on the iron pad, is used to clamp and fix the rail; The bolt of the turnout sleeper bolt passes through the upper hole section, the rubber pad, and the iron pad in sequence and then protrudes upwards. The rubber pad and the iron pad are pressed and fixed in the installation groove by the fastening assembly.

[0016] In some possible implementations, the fastening system includes a spring clip and a fastening bolt, with an iron seat fixedly mounted on the iron pad. The fastening bolt passes through the spring clip and connects to the iron seat, thereby pressing and fixing the rail between the spring clip and the iron pad.

[0017] Secondly, the present invention also provides a method for manufacturing the above-mentioned concrete turnout sleeper structure, the method comprising the following steps: S1. Making the inner mold: Based on the preset shape and size of the bolt hole, make an inner mold that matches the structure of the bolt hole. The material of the inner mold is a fusible or soluble material. S2. Fixing the mold: Fixing the inner mold in the preset position inside the main concrete mold; S3. Pouring concrete: Pouring concrete into the main concrete mold with the inner mold fixed, and vibrating to compact it; S4. Remove the inner mold: After the concrete has solidified and reached the predetermined strength, remove the inner mold by heating and melting or dissolving it with a solvent to form bolt holes in the concrete pillow.

[0018] This method is key to achieving the aforementioned concrete turnout sleeper structure. Traditional machining methods cannot mill channels with bosses inside concrete. However, lost foam casting technology can form internal cavities of any complex shape with high precision in a single process, including the aforementioned integrated limiting boss, thus solving the manufacturing process problem. The formed concrete turnout sleeper structure has the same technical effects as the aforementioned concrete turnout sleeper structure, which will not be elaborated here.

[0019] Specifically, in the above manufacturing method, in step S2, when fixing the inner mold, the elastic element is pre-fitted onto the inner mold at the position corresponding to the formation of the middle hole segment, so that after pouring in step S3, the elastic element is fixed in the concrete pillow.

[0020] Specifically, in the above manufacturing method, the material of the inner mold is foam plastic or industrial wax.

[0021] Specifically, in the above manufacturing method, in step S4, the inner mold is melted by injecting high-temperature steam or heated air into the channel where the inner mold is located. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 A cross-sectional view of a concrete turnout sleeper structure provided in an embodiment of the present invention; Figure 2 A cross-sectional view of a concrete sleeper provided in an embodiment of the present invention. Figure 3 for Figure 2 The cross-sectional view of the upper hole section of the concrete sleeper at point AA is shown. Figure 4 for Figure 2 The cross-sectional view of the middle hole section of the concrete pillow at point BB is shown. Figure 5 for Figure 2 The cross-sectional view of the upper and lower sections of the concrete sleeper at point CC is shown. Figure 6 This is a flowchart of a method for manufacturing a concrete turnout sleeper structure, provided as an embodiment of the present invention.

[0023] Figure label: 1-Concrete sleeper body; 11-Bolt hole; 111-Upper hole section; 112-Middle hole section; 113-Lower hole section; 12-Anti-rotation structure; 121-Limiting boss; 122-Anti-rotation wall; 13-Mounting groove; 2-Side sleeper bolt; 21-Bolt head; 3-Elastic element; 4-Rubber pad; 5-Iron pad; 6-Fastening system; 61-Elastic strip; 62-Fastening bolt; 7-Rail; 8-Fastening assembly; 81-Nut; 82-Washer; 9-Iron base. Detailed Implementation

[0024] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0025] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0026] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0027] In the description of this invention, it should be understood that the terms "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] As a crucial piece of railway equipment, prestressed concrete sleepers are constantly being upgraded and replaced. The production process of prestressed concrete sleepers is becoming increasingly sophisticated, and their structural performance, production technology and equipment, and product quality are gradually reaching international advanced levels. Currently, domestic concrete sleepers mainly adopt two structural forms: pre-embedded sleeve type (with shoulder) and pre-embedded iron seat type (without shoulder). Both structures belong to the pre-embedded design, and their core components (sleeve or iron seat) must be precisely fixed in designated positions within the sleeper mold before concrete pouring.

[0030] This pre-embedded method brings a significant maintenance challenge: once the pre-embedded parts are damaged (such as rust, cracking, thread failure or positional displacement), the replacement process is extremely complicated and time-consuming. Since the pre-embedded parts are completely wrapped and anchored by concrete, maintenance usually requires: (1) disassembling the rail parts: first, removing all the fasteners, rails and other related parts on the sleeper. (2) removing the sleeper (or local treatment): for ordinary sleepers, it is often necessary to remove the entire sleeper from the track; for special parts such as turnout sleepers, sometimes local cutting or special treatment is required to remove the damaged part. (3) destructive removal and positioning: at the location of the damaged pre-embedded part, the original concrete needs to be destroyed by drilling, chiseling and other methods, and the old pre-embedded part and the surrounding failed concrete need to be carefully removed. (4) re-implantation and pouring: accurately install the new pre-embedded part in the cleaned hole, and then use special repair materials (such as epoxy mortar or fast-hardening high-strength concrete) to fill, level and cure.

[0031] This series of operations is difficult to carry out, involves complex procedures, and is time-consuming. In particular, the newly filled repair material requires sufficient curing time (usually several hours to several days), during which time the sleepers cannot bear the train load, severely restricting the normal operating efficiency of the line. Therefore, damage to embedded parts not only results in high repair costs but also poses a significant challenge to the availability and ease of maintenance of railway lines.

[0032] To solve the above problems, firstly, such as Figure 1 , Figure 2 , Figure 3 and Figure 4As shown in the figure, an embodiment of the present invention provides a concrete turnout sleeper structure, including a concrete sleeper body 1 and turnout sleeper bolts 2. The concrete sleeper body 1 has a bolt channel 11 extending from top to bottom. The bolt channel 11 includes, from top to bottom, a connected upper section 111, a middle section 112, and a lower section 113. The upper section 111 has a first rectangular cross-section. Along the extension direction of the bolt channel 11, the projection of the middle section 112 on the horizontal plane completely covers the projection of the upper section 111. The bolt head 21 of the turnout sleeper bolt 2 has a second rectangular cross-section. The length of the second rectangle is less than the length L of the first rectangle, but greater than the width W of the first rectangle, and the width of the second rectangle is less than the width W of the first rectangle. An integrally formed anti-rotation structure 12 is provided in the middle section 112 to restrict the rotation of the bolt head of the turnout sleeper bolt 2 in the horizontal direction.

[0033] During installation, the bolt head 21 of the turnout bolt 2 is parallel to the length direction of the first rectangle, allowing it to pass downwards through the upper hole section 111 and into the middle hole section 112. When the turnout bolt 2 is rotated a certain angle, the bolt head 21 abuts against the anti-rotation structure 12, thereby limiting its positioning in the horizontal direction. If the turnout bolt 2 is damaged (such as by corrosion, cracking, thread failure, etc.) and needs to be replaced, the turnout bolt 2 is rotated in the reverse direction so that the length direction of the bolt head 21 is parallel to the length direction of the first rectangle, allowing it to be removed from the upper hole section 111. Then, the new turnout bolt 2 is installed onto the concrete sleeper body 1 according to the aforementioned steps.

[0034] Compared to existing technologies, the concrete turnout sleeper structure provided by this invention has a first rectangular cross-section in the upper hole section 111, and a keyed structure with a second rectangular cross-section for the bolt head 2 of the turnout sleeper bolt 2. The length of the second rectangle is less than the length of the first rectangle, and the width of the second rectangle is less than the width of the first rectangle. Therefore, when the bolt head 21 of the turnout sleeper bolt 2 is parallel to the length of the first rectangle, the bolt head 21 can pass through the upper hole section 111 and enter the middle hole section 112. After the turnout sleeper bolt 2 rotates at a certain angle, the first and second rectangles are intersected. Because the length of the second rectangle is greater than the width of the first rectangle, the bolt head 21 cannot extend out of the upper hole section 111 and is thus confined in the middle hole section 112. This achieves the elimination of pre-embedding and effectively prevents rotation, ensuring that during installation, the workers can accurately position the turnout sleeper bolt 2 and prevent the turnout sleeper bolt 2 from rotating to a position where the long side of the bolt head 21 is nearly parallel to the first rectangle, causing the turnout sleeper bolt 2 to slip out of the upper hole section 111 during operation. The process involves passing, rotating, and locking the turnout sleeper bolt 2. During replacement, the bolt 2 is simply rotated in the opposite direction until the length of the bolt head 21 is parallel or nearly parallel to the length of the first rectangle, allowing it to be removed from the upper hole section 111. The new bolt 2 is then installed onto the concrete sleeper body 1. This eliminates the need for pre-embedded bolts or sleeves, removing the complex procedures of precise positioning and fixing of pre-embedded parts before pouring, thus simplifying the turnout sleeper manufacturing process. The separate design of the turnout sleeper bolt 2 and the concrete sleeper body 1 eliminates the need to disassemble numerous rail components, remove the entire concrete sleeper structure, drill or chisel away the concrete sleeper body 1, or wait for the new pouring material to cure. This simplifies the originally complex and time-consuming maintenance work into a simple bolt-level quick disassembly and assembly operation, greatly reducing construction difficulty and cost, thereby improving maintenance efficiency, maintenance costs, and the availability of the railway line.

[0035] In addition, the anti-rotation structure 12 of the concrete pillow 1 is integrally formed with the other parts of the concrete pillow 1, which ensures the integrity and high strength of the concrete pillow 1 and avoids the loosening problem that may be caused by prefabricated parts.

[0036] In addition, the bolt hole 11 is designed to run from top to bottom, allowing rainwater to be drained out from the lower hole section 113, preventing water accumulation in the hole and slowing down the corrosion of the fork bolt 2.

[0037] For example, when the bolt head 21 of the turnout bolt 2 enters the middle hole section 112 and rotates 90°, the first rectangle and the second rectangle are orthogonally distributed. Since the length of the second rectangle is greater than the width of the first rectangle, the turnout bolt 2 is prevented from protruding from the upper hole section.

[0038] In some possible implementations, the anti-rotation structure 12 includes two inwardly protruding limiting bosses 121 integrally formed at two corners symmetrical to the diagonal of the first rectangle within the central hole section 112. The inner surfaces of the limiting bosses 121 form anti-rotation walls 122. When the turnout bolt 2 rotates a certain angle, the long side wall of the bolt head 21 abuts against the anti-rotation wall 122, thereby limiting its positioning in the horizontal direction. During installation, the bolt head 21 of the turnout bolt 2, with its length direction parallel to the length direction of the first rectangle, passes downward through the upper hole section 111 and enters the central hole section 112. When the turnout bolt 2 rotates a certain angle (exemplarily, the certain angle can be 70°, 80°, 90°, 100°, 110°, etc., as long as it can ensure that the bolt head 21 cannot protrude from the upper hole section 111), the long side wall of the bolt head 21 abuts against the anti-rotation wall 122, which is used to limit the positioning of the bolt head 21 in the horizontal direction.

[0039] For example, the anti-rotation wall 122 can be perpendicular or nearly perpendicular to the long side of the first rectangle. After the bolt head 21 of the fork bolt 2 enters the middle hole section 112, it can rotate 90° first. At this time, the first rectangle and the second rectangle are orthogonally distributed, thereby preventing the fork bolt from protruding from the upper hole section.

[0040] As an example, the anti-rotation wall 122 can also be other shapes, and the anti-rotation wall 122 and the long side of the first rectangle can also have other angles, as long as the bolt head 21 can be limited. The embodiments of the present invention do not make specific limitations.

[0041] In some possible implementations, such as Figure 3 As shown, the width W of the cross-section of the upper hole section 111 can be 1.05-1.2 times the width of the bolt head 21; for example, the width W of the cross-section of the upper hole section 111 can be 1.05, 1.1, 1.15, or 1.2 times the width of the bolt head 21. The length L of the cross-section of the upper hole section 111 is 1.1-1.3 times the length of the bolt head 21; for example, the length L of the cross-section of the upper hole section 111 is 1.1, 1.2, or 1.3 times the length of the bolt head 21. When the width or length of the cross-section of the upper hole section 111 is too small, the bolt head 21 may not be able to pass smoothly through the upper hole section 111 into the middle hole section 112. When the width or length of the cross-section of the upper hole section 111 is too large, the forklift bolt 2 may be loose in the bolt hole 11, affecting the fixing effect of the forklift bolt 2.

[0042] In some embodiments, the lower hole section 113 has a circular cross-section, the diameter of which is smaller than the length of the second rectangle. This configuration prevents the bolt head 21 from passing through the lower hole section 113, thereby limiting the position of the turnout bolt 2 in the vertical direction and preventing it from falling to the bottom.

[0043] In some other possible implementations, the cross-section of the lower hole section 113 is a third rectangle, the length of which is less than the length of the second rectangle. Similarly, the bolt head 21 cannot pass through the lower hole section 113, thus limiting the switch bolt 2 in the vertical direction and preventing the switch bolt 2 from falling to the bottom.

[0044] In other possible implementations, such as Figure 4 and Figure 5 As shown, the cross-sectional shape of the lower hole section 113 is the same as that of the middle hole section 112, but the cross-sectional shape of the lower hole section 113 is smaller than that of the middle hole section 112. Along the length direction of the first rectangle, the length l of the cross-section of the lower hole section 113 is smaller than the length of the second rectangle. Along the width direction of the first rectangle, the width w of the cross-section of the lower hole section 113 is smaller than the width of the second rectangle. Similarly, the bolt head 21 cannot pass through the lower hole section 113, thus limiting the position of the turnout bolt 2 in the vertical direction and preventing it from falling to the bottom. Furthermore, the cross-sectional shape of the lower hole section 113 is the same as that of the middle hole section 112, but smaller. This arrangement results in a smoother transition between the inner walls of the middle hole section 112 and the lower hole section 113, helping to reduce stress concentration and improve the stability of the internal structure of the bolt hole 11.

[0045] In some possible implementations, along the width direction of the first rectangle, the width of the cross-section of the lower hole section 113 is 0.7-0.9 times the width of the bolt head 21; exemplaryly, the width of the cross-section of the lower hole section 113 is 0.7, 0.8, or 0.9 times the width of the bolt head 21. Along the length direction of the first rectangle, the length of the cross-section of the lower hole section 113 is 0.7-0.9 times the length of the bolt head 21; exemplaryly, the length of the cross-section of the lower hole section 113 is 0.7, 0.8, or 0.9 times the length of the bolt head 21. If the width or length of the cross-section of the lower hole section 113 is too small, water may not be able to flow smoothly out of the bolt hole 11; if the width or length of the cross-section of the lower hole section 113 is too large, the turnout bolt 2 may enter the lower hole section 113, failing to effectively limit the turnout bolt 2 in the vertical direction.

[0046] In some possible implementations, such as Figure 1As shown, the concrete turnout sleeper structure also includes an elastic element 3, which is disposed within the middle hole section 112 and located between the end face of the upper hole section 111 facing the middle hole section 112 and the bolt head 21; the top surface of the elastic element 3 is connected to the end face of the upper hole section 111 facing the middle hole section 112. Exemplarily, the elastic element 3 can be a nylon or rubber component, etc. The elastic element 3 can: 1. Buffer and dampen shock: effectively absorb and buffer the dynamic impact load generated when a train passes, protecting the concrete sleeper 1 from being broken. 2. Distribute stress: more evenly transfer the concentrated stress transmitted from the bolt head 21 to the concrete body, improving the stress state. 3. Assist in preventing loosening: its elastic force can provide a continuous preload to the turnout sleeper bolt 2 system, inhibiting the possible loosening of the turnout sleeper bolt 2 under vibration. 4. Reduce noise: reduce the noise from hard impact and friction between the bolt head 21 and the inner wall of the concrete.

[0047] In some possible implementations, such as Figure 2 As shown, the top surface of the concrete sleeper 1 is provided with an installation groove 13, and the bottom wall of the installation groove 13 is provided with an entrance to the upper hole section 111. The concrete sleeper structure also includes a rubber pad 4, an iron pad 5, and a fastening system 6. The iron pad 5 and the rubber pad 4 are arranged sequentially from top to bottom in the installation groove 13. The fastening system 6 is set on the iron pad 5 and is used to press and fix the rail 7. The bolt of the sleeper bolt 2 passes through the upper hole section 111, the rubber pad 4, and the iron pad 5 in sequence and extends upwards. The rubber pad 4 and the iron pad 5 are pressed and fixed in the installation groove 13 by the fastening assembly 8. For example, the fastening assembly 8 may include a nut 81 and a washer 82. For further example, the nut 81 may be a self-locking nut or a lock nut. This configuration achieves a high degree of modularity. The installation groove 13 provides precise positioning and accommodating space for the iron pad 5 and the rubber pad 4. The turnout sleeper bolt 2 is responsible for anchoring the iron pad 5 to the concrete sleeper body 1, making the entire superstructure (iron pad 5, fastener, rail 7) a modular unit that can be quickly disassembled and assembled. During maintenance, if only the bolt needs to be replaced, the entire superstructure does not need to be disturbed; if the entire module needs to be replaced, disassembly is also extremely convenient.

[0048] For example, the fastening assembly 8 may also include an anti-rotation component to prevent the nut 81 or the fork bolt 2 from rotating, causing the bolt head 21 of the fork bolt 2 to rotate to a position where its long side is parallel to the long side of the upper hole section 111 and fall out of the upper hole section 111.

[0049] In some possible implementations, such as Figure 1As shown, the fastening system 6 includes a spring clip 61 and a fastening bolt 62. An iron seat 9 is fixedly mounted on the iron base plate 5. The fastening bolt 62 passes through the spring clip 61 and connects to the iron seat 9, thereby pressing and fixing the rail 7 between the spring clip 61 and the iron base plate 5. The turnout sleeper bolt 2 connects the concrete sleeper body 1 to the iron base plate 5, and the fastening bolt 62 of the fastening system 6 connects the iron base plate 5 to the rail 7. The two-stage system has clearly defined functions and does not interfere with each other, thus achieving stable fixing of the rail 7.

[0050] For example, the fastening bolt 62 can be a double-ended bolt, which is threaded to the iron base 9 and then used with a nut to fix the spring clip 61 and the rail 7. Alternatively, for another example, the fastening bolt 62 is fixed to the iron base 9 and then used with a nut to fix the spring clip 61 and the rail 7.

[0051] Secondly, such as Figure 1 and Figure 6 As shown, the present invention also provides a method for manufacturing the above-mentioned concrete turnout sleeper structure, the method comprising the following steps: S1. Making an inner mold: Based on the preset shape and size of the bolt hole 11, make an inner mold that matches the structure of the bolt hole 11. The material of the inner mold is a fusible or soluble material. S2. Fixing the mold: Fixing the inner mold in the preset position inside the main concrete mold; S3. Pouring concrete: Pouring concrete into the main concrete mold with the inner mold fixed, and vibrating to compact it; S4. Remove the inner mold: After the concrete has solidified and reached the predetermined strength, remove the inner mold by heating and melting or by dissolving it with a solvent, forming bolt holes 11 in the concrete pillow 1.

[0052] Traditional machining methods cannot mill bolt holes 11 with limiting bosses 121 inside concrete. However, lost foam casting technology can form bolt holes 11 of any complex shape in a single, high-precision process, solving the manufacturing challenges and enabling the fabrication of the aforementioned concrete turnout sleeper structure. The concrete turnout sleeper structure obtained through this process achieves the same technical effects as the previously described concrete turnout sleeper structure, and will not be elaborated further in this embodiment.

[0053] Specifically, in the above manufacturing method, in step S2, when fixing the inner mold, the elastic element 3 is pre-fitted onto the inner mold at the position corresponding to the formation of the central hole segment 112, so that after pouring in step S3, the elastic element 3 is fixed in the concrete pillow body 1. This achieves precise pre-embedded positioning of the elastic element 3. By fixing it to the inner mold before pouring, it can be ensured that after the concrete is formed, the elastic element 3 is in the designated position, and its top surface can be tightly connected to the end face of the upper hole segment 111, ensuring the best performance and stress state.

[0054] Specifically, in the above manufacturing method, the inner mold material is either foam plastic or industrial wax. Foam plastic is inexpensive, and industrial wax is recyclable and reusable; both are mature and reliable lost foam casting materials.

[0055] Specifically, in the above manufacturing method, in step S4, the inner mold is melted by injecting high-temperature steam or heated air into the channel where the inner mold is located. Removing the inner mold using a high-temperature fluid (steam or hot air) is an efficient, clean, and easily industrialized method. The fluid can fully contact the surface of the inner mold, causing it to melt or vaporize quickly and completely and be carried out. The resulting channel has a smooth inner wall, eliminating the need for secondary cleaning.

[0056] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0057] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A concrete switch tie structure, characterized by, include: A concrete pillow body (1) is provided with a bolt channel (11) that runs from top to bottom. The bolt channel (11) includes, from top to bottom, an upper section (111), a middle section (112), and a lower section (113) that are connected. The cross-section of the upper section (111) is a first rectangle. Along the extension direction of the bolt channel (11), the projection of the middle section (112) on the horizontal plane completely covers the projection of the upper section (111). Forklift bolt (2), the cross-section of the bolt head (21) of the forklift bolt (2) is a second rectangle, the length of the second rectangle is less than the length of the first rectangle and greater than the width of the first rectangle, and the width of the second rectangle is less than the width of the first rectangle; The central hole section (112) is provided with an integrally formed anti-rotation structure (12) for limiting the rotation of the bolt head (21) of the fork bolt (2) in the horizontal direction.

2. The concrete switch tie structure of claim 1, wherein, The anti-rotation structure (12) includes two integrally formed inwardly protruding limiting bosses (121) at two corners symmetrical to the diagonal of the first rectangle within the central hole section (112), and the inner side of the limiting bosses (121) forms an anti-rotation wall (122). During installation, the bolt head (21) of the forklift bolt (2) is parallel to the length direction of the first rectangle and passes downward through the upper hole section (111) into the middle hole section (112); when the forklift bolt (2) rotates a certain angle, the long side wall of the bolt head (21) abuts against the anti-rotation wall (122), and the anti-rotation wall (122) is used to limit the positioning of the bolt head (21) in the horizontal direction.

3. The concrete turnout sleeper structure according to claim 1 or 2, characterized in that, The width of the cross section of the upper hole (111) is 1.05-1.2 times the width of the bolt head (21), and its length is 1.1-1.3 times the length of the bolt head.

4. The concrete turnout sleeper structure according to claim 1 or 2, characterized in that, The cross-section of the lower hole section (113) is circular, and its diameter is smaller than the length of the second rectangle; Alternatively, the cross-section of the lower hole segment (113) is a third rectangle, and the length of the third rectangle is less than the length of the second rectangle; Alternatively, the shape of the cross-section of the lower hole segment (113) is the same as that of the cross-section of the middle hole segment (112), and the cross-section of the lower hole segment (113) is smaller than that of the middle hole segment (112). Along the length direction of the first rectangle, the length of the cross-section of the lower hole segment (113) is smaller than the length of the second rectangle, and along the width direction of the first rectangle, the width of the cross-section of the lower hole segment (113) is smaller than the width of the second rectangle.

5. The concrete turnout sleeper structure according to claim 4, characterized in that, Along the width direction of the first rectangle, the width of the cross section of the lower hole segment (113) is 0.7-0.9 times the width of the bolt head (21), and along the length direction of the first rectangle, the length of the cross section of the lower hole segment (113) is 0.7-0.9 times the length of the bolt head (21).

6. The concrete turnout sleeper structure according to claim 1 or 2, characterized in that, The concrete fork sleeper structure also includes an elastic element (3), which is disposed in the middle hole section (112) and located between the end face of the upper hole section (111) facing the middle hole section (112) and the bolt head (21); the top surface of the elastic element (3) is connected to the end face of the upper hole section (111) facing the middle hole section (112).

7. The concrete turnout sleeper structure according to claim 1 or 2, characterized in that, The top surface of the concrete pillow (1) is provided with an installation groove (13), and the bottom wall of the installation groove (13) is provided with the entrance of the upper hole section (111). The concrete turnout sleeper structure also includes: Rubber pad (4) and iron pad (5) are arranged in the mounting groove (13) from top to bottom; The fastening system (6) is set on the iron pad (5) and is used to press and fix the steel rail (7). The screw of the fork bolt (2) passes through the upper hole section (11), the rubber pad (4), and the iron pad (5) in sequence and extends upward. The rubber pad (4) and the iron pad (5) are pressed and fixed in the mounting groove (13) by the fastening assembly (8).

8. A concrete turnout sleeper structure according to claim 7, characterized in that, The fastening system (6) includes a spring clip (61) and a fastening bolt (62). An iron seat (9) is fixedly installed on the iron pad (5). The fastening bolt (62) passes through the spring clip (61) and is connected to the iron seat (9), thereby pressing and fixing the rail (7) between the spring clip (61) and the iron pad (5).

9. A method for manufacturing a concrete turnout sleeper structure as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Making an inner mold: Based on the preset shape and size of the bolt hole, make an inner mold that matches the structure of the bolt hole. The material of the inner mold is a fusible or soluble material. S2. Fixing the mold: Fixing the inner mold at a preset position inside the main concrete mold; S3. Pouring concrete: Pouring concrete into the main concrete mold with the inner mold fixed thereon, and compacting it by vibration. S4. Remove the inner mold: After the concrete has solidified and reached the predetermined strength, remove the inner mold by heating and melting or by dissolving it with a solvent, thus forming the bolt holes in the concrete pillow.

10. The manufacturing method according to claim 9, characterized in that, In step S2, when fixing the inner mold, the elastic element is also pre-fitted onto the inner mold at the position corresponding to the formation of the middle hole segment. After pouring in step S3, the elastic element is fixed in the concrete pillow.

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