Traction system and method for assisting penetration of full-length prestressed steel strand

Abstract

The invention discloses a traction system and method for assisting penetration of a full-length prestressed steel strand, the traction system comprises a fixing device, a transmission device, a steering device and a traction device.The fixing device comprises a segmental beam, a positioning screw, a segmental beam wet joint, a support and a lateral supporting rod; the transmission device comprises a winch, a base and a steel wire rope, the steering device comprises a cover beam, a fixed supporting frame, a driven pulley, a movable rod, a connecting base, a baffle and a mounting base, the traction device comprises a sleeve, a plain round steel bar, a single-strand steel strand, a four-strand steel strand and a seven-strand steel strand, and the traction system changes the traction direction through the steering device. And the construction area of the tensioning end can be effectively reduced. According to the traction system and method for assisting in strand pulling of the full-length prestressed steel strands, the problem that single strand pulling cannot be completed in a conventional strand pulling mode due to too small pipeline space is solved in a one-belt-multiple mode, and the working efficiency is improved through modular design.

Description

Technical Field

[0001] This invention belongs to the field of bridge prestressed construction technology, and more specifically, relates to a traction system and method for assisting in threading a continuous prestressed steel strand. Background Technology

[0002] In modern bridge and large concrete structure construction, prestressed steel strands are often used to pass through long and complex ducts. The threading of prestressed steel strands is a key link to ensure construction. Its quality and efficiency directly affect the overall progress and safety performance of the project. The core is to accurately and efficiently guide the entire bundle of steel strands into the pre-set duct.

[0003] Traditional strand threading methods rely on manual labor or simple machinery to push the strands one by one, which has problems such as low efficiency, easy tangling of steel strands, and uneven stress. Especially in the process of threading long strands, the frictional resistance between the steel strands and the inner wall of the duct increases significantly, which can easily lead to local stress concentration or even breakage, seriously affecting the construction quality and safety. In addition, existing technologies lack precise control over the dynamic traction force during the threading process, making it difficult to adapt to the continuous operation requirements in complex duct environments.

[0004] The existing technical solutions have the following problems: 1. The prestressed steel strands are long and the duct diameter is large and arranged in a wavy linear shape. During the concrete pouring process, the heat of cement hydration causes the ducts to deform, making it difficult to complete the threading operation using conventional threading equipment; 2. Conventional threading processes often use hydraulic push or winch traction threading machines to push or pull the steel strands one by one. However, when threading the last few steel strands, the deformation of the ducts often results in insufficient remaining space, making it impossible to continue threading. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a traction system and method for assisting in threading long prestressed steel strands. Through the interaction of fixing devices, transmission devices, steering devices, and traction devices, the modular design improves work efficiency. The fixing devices, with three independent support systems, provide redundancy for the traction system, ensuring overall structural stability and safe operation even if one system fails. The transmission device creates a stable force transmission path, reducing the construction risk of wire rope breakage due to excessive tension caused by prestressing jamming during traction. The steering device changes the direction of force, thereby reducing the construction area at the tensioning end.

[0006] To achieve the above objectives, according to a first aspect of the present invention, a traction system for assisting in threading a continuous prestressed steel strand is provided, comprising: The system comprises a fixed device as the main structure of the traction system, a transmission device located in a designated area on the top of the fixed device, a steering device connected to the side of the fixed device, and a traction device with one end connected to the end of the transmission device and the other end connected to the steering device. The fixing device includes a segmental beam as the main structure, a positioning screw bolted to the outer top of the segmental beam, a wet joint of the segmental beam located at the front end of the segmental beam, a support bracket bolted to the top of the segmental beam and connected to a pad plate, and a lateral support rod with one end tightly attached to the side wall of the wet joint of the segmental beam and the other end connected to a hole on the side top of the support bracket. The steering device includes a cap beam whose sidewalls are bolted to the segment beam, a connecting seat on the sidewall of the cap beam, and a fixed support frame inserted into the connecting seat and connected to the sidewall of the cap beam. The traction device includes a U-shaped steel structure connected to the end of a wire rope, and a sleeve connected to both sides of one end of the steel bar.

[0007] Furthermore, the fixing device is equipped with three independent support systems to provide redundancy protection.

[0008] Furthermore, the vertical support of the positioning screw constitutes the first support system, the horizontal support of the lateral support rod constitutes the second support system, and the connection between the support bracket and the segmental beam constitutes the third support system.

[0009] Furthermore, the fixed support frame is connected to five sets of steel bars with a diameter of 20mm in the height direction, and the steel bars are provided with protrusions.

[0010] Furthermore, the fixed support frame has grooves on both sides that connect to the steel rod.

[0011] Furthermore, the transmission device includes a base that is welded to the top surface of the support bracket, and the base and the support bracket form a force transmission path.

[0012] Furthermore, the steering device also includes mounting seats on both sides of the top of the fixed support frame and baffles bolted to the bottom of the mounting seats.

[0013] Furthermore, the steering device also includes a movable rod inserted into the mounting base at both ends and a driven pulley located in the middle of the movable rod. The driven pulley is respectively arranged at the top of the fixed support frame and the tensioning end.

[0014] Furthermore, the traction device also includes a single strand of steel wire disposed inside the sleeve, four strands of steel wire disposed on the single strand of steel wire, and seven strands of steel wire disposed on the four strands of steel wire.

[0015] According to a second aspect of the present invention, a method of using a traction system for assisting in threading a continuous prestressed steel strand is provided, comprising: S100: Measure the on-site construction data in advance, determine the dimensions of the fixing device, steering device and traction device, and send them to the processing plant for prefabrication; S200: After hoisting each device to the design position, install and fix them respectively. Fix one end of the wire rope to the inside of the drum, pass it around the winch and the fixed pulley in sequence, and finally fix it to one end of the traction connector. S300: In the continuous beam introduction section, the single strand of steel strand is pushed to the lead-out end by manual labor or a wire rope threading machine, and then anchored to the other end of the connector using clamps. After a comprehensive check that all devices are installed accurately, the winch is started and the single strand of steel strand is pulled by the wire rope. At the same time, the operating status of each device in the entire system is observed. S400: After the entire traction system is running stably, the three bundles of prestressed steel strands to be pulled are welded to the previous single strand in a triangular arrangement at the introduction section. On the outside of the welding area, the other three bundles of steel strands are fixed by the same process. S500: Start the winch and pull the seven strands of steel wire rope. Observe the system operation status throughout the process. When the connector is about to reach the steering bracket, stop pulling and run the winch in reverse to return the steel wire rope. Cut the single strand of steel wire rope that was originally used to lead out at the tensioning end and re-anchor the cut steel wire rope to the connector. S600: Repeat the above process until all seven steel strands are threaded through to the tensioning end. During the last traction, the number of strands pulled should not exceed four. The operation of the winch should be closely monitored. If a lock-up occurs, the machine must be stopped immediately. S700: Repeat the above process until all prestressed steel strands are pulled to the tensioning end.

[0016] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: 1. The traction system of the present invention improves work efficiency through the interaction of the fixing device, transmission device, steering device and traction device. The modular design improves work efficiency. The fixing device with three independent support systems provides redundancy protection for the traction system. Even if one system fails, the overall structure can still maintain stability and safe operation. The transmission device forms a stable force transmission path, reducing the construction risk caused by wire rope breakage due to excessive tension caused by prestress jamming during traction. The steering device changes the direction of force, thereby reducing the construction area at the tensioning end.

[0017] 2. The fixing device of the present invention uses a segmental beam as the main structure. By setting a wet joint at the front end of the segmental beam, the relative displacement between the segmental beam and the cap beam is avoided while connecting the segmental beam and the cap beam. The positioning screw installed on the outer side of the top of the segmental beam positions the support bracket which is fixed by bolts and pads. The lateral support rod connected between the wet joint of the segmental beam and the lateral support rod further reinforces the support bracket to ensure its stability.

[0018] 3. The steering device of the present invention securely installs the fixed support frame on the side wall of the cover beam through a connecting seat installed on the side wall of the cover beam, connects the movable rod to the fixed support frame through a baffle and a mounting seat, and reduces the friction between the wire rope and the pulley by adjusting the driven pulley to be on the same plane, thereby reducing the adverse effects on the fixed support frame.

[0019] 4. The traction device of the present invention uses U-shaped steel bars to connect to steel wire ropes. By welding multiple strands of steel wire, it can achieve a one-to-many connection, thus avoiding the problem that conventional wire rope connection methods cannot be completed due to the small space in the pipe. Attached Figure Description

[0020] Figure 1 This is a side view of a traction system for assisting in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the traction system fixing device for assisting in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the transmission device of the traction system used to assist in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the steering device of the traction system used to assist in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the traction device of the traction system used to assist in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure between the steering device and the traction device of the traction system used to assist in threading a full-length prestressed steel strand according to an embodiment of the present invention. Figure 7 This is a schematic diagram of the structure of the fixing steel bar of the steering device of the traction system used to assist in threading a continuous prestressed steel strand according to an embodiment of the present invention; Figure 8 This is a flowchart illustrating the operation of a traction system for assisting in threading a continuous prestressed steel strand according to an embodiment of the present invention.

[0021] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1-segment beam, 2-positioning screw, 3-segment beam wet joint, 4-support bracket, 5-lateral support rod, 6-winch, 7-base, 8-wire rope, 9-cap beam, 10-fixed support frame, 11-driven pulley, 12-moving rod, 13-connecting seat, 14-sleeve, 15-plain round steel bar, 16-single strand steel wire, 17-four strand steel wire, 18-seven strand steel wire, 19-baffle, 20-mounting seat. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] In the description of the embodiments of the present invention, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present 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, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first," "second," and "third" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Furthermore, the use of terms such as "horizontal," "vertical," and "sag" does not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of the embodiments of the present invention, "multiple" means at least two.

[0026] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0027] This invention provides a traction system for assisting in threading a continuous prestressed steel strand, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, the system includes a fixing device, a transmission device, a steering device, and a traction device. The fixing device serves as the main structure of the traction system. The wet joint 3 of the segmental beam in the fixing device is bolted to the side wall of the cap beam 9. The transmission device is welded to the top designated area of ​​the support bracket 4 in the fixing device. The steering device is installed and connected to the side of the fixing device. One end of the traction device is connected to the end of the wire rope 8 in the transmission device, and the other end is connected to the fixed support frame 10 in the steering device. The fixing device has three independent support systems with redundancy, ensuring the overall structural stability and safety even if one system fails. In full operation, the vertical support of the positioning screw 2 forms the first support system, the horizontal support of the lateral support rod 5 forms the second support system, and the connection between the support bracket 4 and the segment beam 1 forms the third support system. The transmission device can form a stable force transmission path, which can reduce the construction risk caused by the wire rope breaking due to excessive tension caused by the prestressing getting stuck during the traction process. The steering device changes the direction of force through the driven pulley 11, which can effectively reduce the construction area at the tensioning end. The steering device is equipped with multiple sets of transverse supports through the fixed support frame 10 to adjust the angle of the prestressed steel strand at the relocation end, reduce the frictional resistance between the prestressed steel strand and the pipeline, and improve the efficiency of threading. The traction system of this invention improves work efficiency through the interaction of the fixing device, transmission device, steering device, and traction device. The modular design of the fixing device with three independent support systems provides redundancy protection for the traction system. Even if one system fails, the overall structure can still maintain stability and safe operation. The transmission device forms a stable force transmission path, reducing the construction risk caused by wire rope breakage due to excessive tension caused by prestress jamming during traction. The steering device changes the direction of force, thereby reducing the construction area at the tensioning end.

[0028] Specifically, such as Figure 2As shown, the fixing device includes a segmental beam 1, a positioning screw 2, a segmental beam wet joint 3, a support bracket 4, and a lateral support rod 5. The segmental beam 1 is the main structure of the fixing device. A segmental beam wet joint 3 is provided at the front end of the segmental beam 1 to connect the segmental beam 1 to the cap beam 9, ensuring the integrity of the traction system, thereby improving the bridge's stiffness, stability, and durability, and preventing relative displacement between the segmental beams 1. A limiting hole is opened at the top of the fixing device, and a pre-drilled hole is provided at the top of the segmental beam 1. The positioning screw 2 passes through the limiting hole and the pre-drilled hole and is fixed to the outer top of the segmental beam 1 using bolts. The support bracket 4 is fixedly installed on the top of the segmental beam 1 with bolts and a pad. The outer side of the support bracket 4 has positioning holes that match the positioning screw 2. When installing the segmental beam 1, it is necessary to ensure that the positioning screw 2 passes smoothly through the positioning holes on both sides of the support bracket 4. Then, the support bracket 4 is fixed with bolts. On the side of the support bracket 4 close to the wet joint 3 of the segmental beam, there are also holes for positioning the lateral support rod 5. One end of the lateral support rod 5 is pressed against the side wall of the wet joint 3 of the segmental beam, and the other end passes through the hole on the top side of the support bracket 4 and is fixed with bolts. The fixing device of the present invention uses segmental beams as the main structure. By setting a wet joint at the front end of the segmental beam, the relative displacement between the segmental beam and the cap beam is avoided while connecting the segmental beam and the cap beam. The positioning screw installed on the outer side of the top of the segmental beam positions the support bracket, which is fixed by bolts and pads. The lateral support rod connected between the wet joint of the segmental beam and the lateral support rod further reinforces the support bracket to ensure its stability.

[0029] Specifically, such as Figure 3 As shown, the transmission device includes a winch 6, a base 7, and a wire rope 8. The transmission device is installed on top of the support bracket 4. The base 7 is welded to the top surface of the support bracket 4, forming a stable force transmission path between the base 7 and the support bracket 4. The winch 6 is installed at the center of the top of the base 7. One end of the wire rope 8 starts from the internal drum of the winch 6, and the other end is connected to the driven pulley 11 and the plain round steel bar 15. The rated pulling force of the winch 6 is 10 tons. It is equipped with an emergency braking system and an electronic display system. The emergency braking system can automatically monitor the pulling force and trigger the brake when it exceeds 6 tons. The electronic display system can display the current pulling force value of the winch in real time.

[0030] Specifically, in the transmission device, the actual traction force required by winch 6 during the winding process is... P It must be greater than the total frictional resistance generated by the steel strand within the duct. and overcoming the resistance of the threading equipment The combined force, multiplied by a safety factor. K。

[0031] in, P This refers to the tension in the steel strand as it begins to enter the duct at the traction end of the winch. K For safety factors (usually taken as 1.2 to 1.5), This represents the total frictional resistance generated by the steel strand within the duct. To overcome the resistance of the threading equipment.

[0032] Total frictional resistance The calculation follows Euler's formula deformation in prestressed construction: in, This refers to the tension in the steel strand at the lead-out end of the duct. L This refers to the length of the steel strand bundle. μ It is the coefficient of friction between the steel strand and the inner wall of the corrugated pipe (usually taken as 0.10 to 0.30). α Length of steel strand bundle L Total turning angle of the curve within (in radians). It is the duct deviation coefficient (usually taken as 0.001 to 0.003 / m).

[0033] The above calculations yield the minimum theoretical traction force required for the steel strand to travel within the duct. However, in actual construction, the winch 6 provides... P It must be sufficient to overcome the total frictional resistance .

[0034] Specifically, such as Figure 4 , Figure 7As shown, the steering device includes a cover beam 9, a fixed support frame 10, a driven pulley 11, a movable rod 12, a connecting seat 13, a baffle 19, and a mounting base 20. The cover beam 9 serves as the main structure of the steering device. The side of the cover beam 9 is securely connected to the segment beam 1 by bolts. The connecting seat 13 is bolted to the side wall of the cover beam 9. The bottom of the fixed support frame 10 is inserted into the connecting seat 13, which fixes the fixed support frame 10 to the side wall of the cover beam 9. The top of the fixed support frame 10 is adjusted according to the required angle of the cover beam 9 and the length of the fixed support frame 10 based on the steel strand. Five sets of steel bars with a diameter of 20mm are connected to the fixed support frame 10 in the height direction. Grooves are provided on both sides of the fixed support frame 10, and protrusions that mate with the grooves are provided on the steel bars. This design creates a sliding connection between the steel bars and the fixed support frame 10, preventing relative rotation and ensuring easy installation of the steel bars. Mounting seats 20 are installed on both sides of the top of the fixed support frame 10. Baffles 19 are installed at the bottom of the mounting seats 20 by bolts. The two ends of the movable rod 12 are inserted into the interior of the mounting seats 20 and locked onto the mounting seats 20 by the baffles 19. The movable rod 12 is connected to the mounting seats 20 on both sides of the top of the fixed support frame 10 through the baffles 19. A driven pulley 11 is installed in the middle of the movable rod 12. The driven pulleys 11 are respectively arranged at the top and tensioning end of the fixed support frame 10 to ensure that the angle of the pulled steel strand exiting the cover beam is basically straight. In actual installation, it should be ensured that the upper and lower driven pulleys 11 are in the same plane as the winch 6 to reduce the friction between the wire rope 8 and the pulley and reduce the adverse effects on the fixed support frame 10. In addition, since there is usually more than one prestressed duct that needs to be threaded in actual engineering, the mounting seats 20 are also provided on the fixed support frame 10 to adapt to the traction requirements of different ducts. The steering device of the present invention securely installs the fixed support frame on the side wall of the cover beam through a connecting seat installed on the side wall of the cover beam, and connects the movable rod to the fixed support frame through a baffle and a mounting seat. By adjusting the driven pulley and the winch to be on the same plane, the friction between the wire rope and the pulley is reduced, thereby reducing the adverse effects on the fixed support frame.

[0035] Specifically, such as Figure 5 , Figure 6As shown, the traction device includes a sleeve 14, a plain round steel bar 15, a single-strand steel strand 16, a four-strand steel strand 17, and a seven-strand steel strand 18. The plain round steel bar 15 is a U-shaped steel structure and is connected to the other end of the wire rope 8. The plain round steel bar 15 is welded to both ends of the outer side of the sleeve 14. Only the single-strand steel strand 16 can pass through the inside of the sleeve 14 and is anchored to one end of the sleeve by a clamp. During construction, three steel strands are first welded to the single-strand steel strand 16 in a triangular arrangement to form a four-strand steel strand 17. Then, another three steel strands are welded to the four-strand steel strand 17 in the same way to finally form a seven-strand steel strand 18. It should be noted that the traction device must maintain a reasonable angle with the prestressed duct and the cap beam 9 to minimize the frictional resistance between the steel strands and the duct wall. The traction device of the present invention uses U-shaped steel bars to connect to steel wire ropes. By welding multiple strands of steel wire, it can achieve a one-to-many connection, avoiding the problem that conventional wire rope connection methods cannot be completed due to the small space in the pipe.

[0036] like Figure 8 As shown, in another embodiment of the present invention, a method for using a traction system for assisting in threading a continuous prestressed steel strand is provided, comprising the following steps: Measure the on-site construction data in advance, determine the dimensions of the fixing device, steering device and traction device, and send them to the processing plant for prefabrication.

[0037] After each device is hoisted to the design position, it is installed and fixed. One end of the wire rope 8 is fixed inside the drum, and it passes around the winch 6 and the fixed pulley in sequence, and is finally fixed to one end of the traction connector.

[0038] In the continuous beam introduction section, the single strand steel strand 16 is pushed to the lead-out end manually or by a threading machine, and then anchored to the other end of the connector using clamps. After a comprehensive check that all devices are installed correctly, the winch 6 is started, and the single strand steel strand 16 is pulled by the wire rope 8. At the same time, the operating status of each device in the entire system is observed.

[0039] After the entire traction system is running stably, the three bundles of prestressed steel strands to be pulled are welded to the previous single strand 16 in a triangular arrangement at the lead-in section. On the outside of the welding area, the other three bundles of steel strands are fixed by the same process.

[0040] Start the winch 6 to pull the seven-strand steel cable 18. Observe the system operation status throughout the process. When the connector is about to reach the steering bracket, stop the traction and run the winch 6 in reverse to return the steel cable 8. Cut the single strand steel cable 16 originally used for lead-out at the tensioning end and re-anchor the cut steel cable to the connector.

[0041] Repeat the above process until all seven strands of steel wire 18 are threaded through to the tensioning end. During the last traction, the number of strands pulled should not exceed four. The operating status of the winch 6 should be closely monitored. If a lock-up occurs, the machine must be stopped immediately.

[0042] Repeat the above process until all prestressed steel strands are pulled to the tensioning end.

[0043] In summary, the traction system and method for assisting in threading long prestressed steel strands avoids the problem of single-strand threading being impossible due to limited duct space in conventional threading methods by using a one-to-many approach, and improves work efficiency through modular design.

[0044] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A traction system for assisting in threading a continuous prestressed steel strand, characterized in that, include: The system comprises a fixed device as the main structure of the traction system, a transmission device located in a designated area on the top of the fixed device, a steering device connected to the side of the fixed device, and a traction device with one end connected to the end of the transmission device and the other end connected to the steering device. The fixing device includes a segmental beam (1) as the main structure, a positioning screw (2) bolted to the outer top of the segmental beam (1), a segmental beam wet joint (3) located at the front end of the segmental beam (1), a support bracket (4) bolted to the top of the segmental beam (1) and a pad, and a lateral support rod (5) with one end tightly attached to the side wall of the segmental beam wet joint (3) and the other end connected to the side hole on the top of the support bracket (4). The steering device includes a cap beam (9) whose side wall is bolted to the segment beam (1), a connecting seat (13) on the side wall of the cap beam (9), and a fixed support frame (10) inserted into the connecting seat (13) and connected to the side wall of the cap beam (9). The traction device includes a U-shaped steel structure connected to the end of a steel wire rope (8) with a plain round steel bar (15) and a sleeve (14) connected to both sides of one end of the plain round steel bar (15).

2. The traction system for assisting in threading a continuous prestressed steel strand according to claim 1, characterized in that, The fixing device is equipped with three independent support systems to provide redundancy protection.

3. A traction system for assisting in threading a continuous prestressed steel strand according to claim 2, characterized in that, The vertical support of the positioning screw (2) is the first support system, the horizontal support of the lateral support rod (5) is the second support system, and the connection between the support bracket (4) and the segment beam (1) is the third support system.

4. A traction system for assisting in threading a continuous prestressed steel strand according to claim 3, characterized in that, The fixed support frame (10) is connected to five sets of steel bars with a diameter of 20 mm in the height direction, and the steel bars are provided with protrusions.

5. A traction system for assisting in threading a continuous prestressed steel strand according to claim 4, characterized in that, The fixed support frame (10) has grooves on both sides that connect to the steel rod.

6. A traction system for assisting in threading a continuous prestressed steel strand according to any one of claims 1-5, characterized in that, The transmission device includes a base (7) that is welded to the top surface of the support bracket (4), and the base (7) and the support bracket (4) form a force transmission path.

7. A traction system for assisting in threading a continuous prestressed steel strand according to any one of claims 1-5, characterized in that, The steering device also includes mounting seats (20) located on both sides of the top of the fixed support frame (10) and baffles (19) bolted to the bottom of the mounting seats (20).

8. A traction system for assisting in threading a continuous prestressed steel strand according to claim 7, characterized in that, The steering device also includes a movable rod (12) inserted into the mounting base (20) at both ends and a driven pulley (11) located in the middle of the movable rod (12). The driven pulley (11) is respectively arranged at the top of the fixed support frame (10) and the tensioning end.

9. A traction system for assisting in threading a continuous prestressed steel strand according to any one of claims 1-5, characterized in that, The traction device also includes a single strand steel wire (16) disposed inside the sleeve (14), a four strand steel wire (17) disposed on the single strand steel wire (16), and a seven strand steel wire (18) disposed on the four strand steel wire (17).

10. A method of using a traction system for assisting in threading a continuous prestressed steel strand, characterized in that, The traction system for assisting in threading a continuous prestressed steel strand, as described in any one of claims 1-9, is used to achieve this, comprising: S100: Measure the on-site construction data in advance, determine the dimensions of the fixing device, steering device and traction device, and send them to the processing plant for prefabrication; S200: After hoisting each device to the design position, install and fix them respectively. Fix one end of the wire rope (8) inside the drum, pass it around the winch (6) and the fixed pulley in sequence, and finally fix it to one end of the traction connector. S300: In the continuous beam introduction section, the single strand steel strand (16) is pushed to the lead-out end by manual labor or a threading machine, and the clamp is used to anchor it to the other end of the connector. After a comprehensive check that the installation of each device is accurate, the winch (6) is started and the single strand steel strand (16) is pulled by the wire rope (8). At the same time, the operating status of each device in the whole system is observed. S400: After the entire traction system is running stably, the three bundles of prestressed steel strands to be pulled are welded to the previous single strand (16) in a triangular arrangement at the introduction section. On the outside of the welding area, the other three bundles of steel strands are fixed by the same process. S500: Start the winch (6) and pull the seven strands of steel wire (18). Observe the system operation status throughout the process. When the connector is about to reach the steering bracket, stop pulling and run the winch (6) in reverse to send back the wire rope (8). Cut the single strand of steel wire (16) that was originally used to lead out at the tensioning end and re-anchor the cut steel wire to the connector. S600: Repeat the above process until all seven strands (18) are pulled out to the tensioning end. During the last traction, the number of strands pulled should not exceed four. The operation status of the winch (6) should be closely monitored. If a lock-up occurs, the machine must be stopped immediately. S700: Repeat the above process until all prestressed steel strands are pulled to the tensioning end.

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