Prestressed structural steel strand bundle threading construction method

Abstract

The present application relates to steel strand bundle penetrating technology field, especially a kind of prestressed structural steel strand bundle penetrating construction method, by steel strand blanking processing into single steel strand with exposed center wire, then single steel strand is bundled into bundle steel strand, and bundle to the edge wire position, so that the center wire is free;And the improvement design of the structure of penetrating device, so that several steel strand clamping assemblies are formed on the penetrating device;When the bundle steel strand is connected with the penetrating device, the center wire is clamped and connected with the steel strand clamping assembly one by one, forming traction steel strand bundle, so that during the pulling process of traction device, the fixture is enhanced the tightness of center wire clamping by the friction between corrugated pipe and core, can effectively avoid fixture from falling off from core and reduce the probability of center wire from penetrating device, improve construction efficiency.

Description

Technical Field

[0001] This invention relates to the field of steel strand bundling and threading technology, and in particular to a construction method for bundling and threading prestressed structural steel strands. Background Technology

[0002] With the rapid development of prestressed technology in beam and / or slab structures, its construction techniques have become nearly perfected. In such projects, it is often necessary to pass several strands of prestressed steel strands through a corrugated pipe. Since a prestressed steel strand is composed of a center wire and several edge wires spirally wound, the existing method for passing these strands through a corrugated pipe is to thread each strand individually. However, this method results in uneven tension distribution due to the strands becoming entangled, and can even occupy the limited cross-sectional space of the corrugated pipe, preventing the last few strands from being threaded through. For example, the prestressed steel strand threading device in the corrugated pipe described in patent number 201020588579.5 discloses a construction method for passing prestressed steel strands through a corrugated pipe.

[0003] Therefore, the construction of prestressed steel strand centralized threading corrugated pipe has been rapidly developed and researched. For example, the prestressed steel strand threading corrugated pipe device with patent number 201020588579.5 is designed to solve the defects of existing technologies where a single prestressed steel strand repeatedly passes through the corrugated pipe. It utilizes a combination of a traction device and a bundler, with several through holes on the bundler. The diameter of the through holes is larger than the core diameter of the prestressed steel strand to be threaded through the corrugated pipe. The radial dimensions of both the traction device and the bundler are smaller than the inner diameter of the corrugated pipe. During construction, a portion of the outer steel wire of the prestressed steel strand is removed, exposing the central steel wire, which passes through the corresponding through hole. The portion passing through the through hole is flattened and anchored. Then, the bundler is screwed into the traction device and tightened, making the traction device and the bundler a whole. Finally, a winch is used to thread the strand through the corrugated pipe, achieving centralized threading.

[0004] For example, the construction method for threading prestressed steel strands in patent number 201010583097.5 discloses processing the traction end of each steel strand so that one wire protrudes a certain length beyond the others. All the steel strands in the bundle are then bundled together, and the protruding wire of each strand is fixed to a threading anchor. The front end of the threading anchor is connected to the traction wire rope of the traction device, and its rear end is connected to the protruding wire of the steel strand. The traction wire rope drives the steel strand bundle to move within a corrugated pipe through the threading anchor. The threading anchor includes a body, which is composed of an anchor plate and a hollow anchor head. The anchor plate has several threading holes, and the front end of the anchor head has a traction wire rope hole. Insertion holes are correspondingly provided between the anchor plate and the anchor head, and insertion rods are placed in these holes. This avoids thermal stress on the steel strand bundle caused by end welding, improving the overall efficiency of threading the bundle.

[0005] It is evident that existing technologies disclose the use of a bundling device to gather the prestressed steel strands that need to pass through the corrugated pipe. This bundling device is then connected to the traction device to form a single threading device. The entire device is then pulled by a traction machine or winch, allowing the bundled prestressed steel strands to pass through the corrugated pipe as a whole, avoiding the defects associated with single strands. However, existing methods for threading steel strands involve flattening and anchoring the center wire, binding or welding it to the bundling device, then tightening the bundling device to the traction head or connecting it with pins. The wire rope on the traction device is then passed through the corrugated pipe and connected to the traction head, allowing the traction device to pull and complete the threading operation. This method makes it easy for the prestressed steel strands to detach when passing through the corrugated pipe as a whole, affecting construction efficiency.

[0006] In view of this, based on long-term construction experience, this researcher has introduced a method to address the shortcomings of existing steel strand bundling and threading corrugated pipes. The method involves bundling the steel strands into bundles, allowing the middle wires of each strand to be free. By combining the design and improvement of the clamp and core structure of the threading device, the steel strands and the threading device are clamped and connected, providing a new approach for the bundling and threading of prestressed steel strands. Summary of the Invention

[0007] In order to solve the above-mentioned technical problems in the prior art, the present invention provides a method for constructing prestressed structural steel strand bundles.

[0008] Specifically, this is achieved through the following technical solutions:

[0009] The method for bundling and threading prestressed steel strands involves connecting the steel strands to a threading device via clamping, and specifically includes the following steps:

[0010] S1: According to the requirements of the prestressed structure design, determine the number of steel strand bundles to be used and the number of steel strands in each bundle, and carry out steel strand cutting and processing; when cutting and processing the steel strands, peel off and cut off the edge wire at the left end of each steel strand, leaving the middle wire, so that the left end of the middle wire is exposed from the left end of the edge wire for a certain length, and bundle the cut steel strands into bundled steel strands, and bundle them to the edge wire position, so that the middle wire is free;

[0011] S2: Connect the bundled steel strands to the threading device, and the bundled threading device is provided with several steel strand clamping assemblies; the threading device includes a clamp and a traction core, the traction core includes a traction head and a core body, the core body and the traction head are integrally formed; the core body is conical, and the diameter of the end of the core body connected to the traction head is less than the diameter of the end of the core body away from the traction head; the clamp is conical, and the clamp can pass the traction core through the traction head end from the bottom end of the conical clamp, so that the clamp is sleeved on the core body; the distance between the inner wall of the clamp and the outer wall of the core body is ≤2mm, and several steel strand clamping assemblies are provided between the inner wall of the clamp and the outer wall of the core body; when the bundled steel strands are connected to the threading device, the middle wire is clamped and connected to the steel strand clamping assemblies one by one to form a traction steel strand bundle;

[0012] S3: Pass the traction wire rope on the traction device through the corrugated pipe of the prestressed structure beforehand, and then fix the traction wire rope to the traction head on the traction strand bundle; start the traction device, and the traction wire rope drives the traction strand bundle through the corrugated pipe. After the traction is in place, cut the exposed middle wire of the traction strand bundle.

[0013] The steel strands are processed into single strands with exposed center wires, and then bundled into bundles, extending to the edge wire position, leaving the center wire free. An improved design of the threading device structure creates several steel strand clamping assemblies. When connecting the bundled steel strands to the threading device, the center wires are clamped one-to-one with the clamping assemblies to form a traction steel strand bundle. The traction wire rope on the traction device then passes through a prestressed corrugated pipe before connecting to the bundle. The fixed connection of the traction head allows the traction steel strand bundle to pass through the corrugated pipe under the traction action of the traction device. As the traction device pulls, the clamps are subjected to friction between the corrugated pipe and the core, which enhances the tightness of the clamps holding the middle wire. This effectively prevents the clamps from falling off the core and reduces the probability of the middle wire falling off the threading device, improving construction efficiency. It also avoids the defects of thermal stress on the steel strand caused by welding connections and avoids the need for reprocessing the ends. The threading process can adapt to changes in the corrugated pipe structure, reducing construction difficulty.

[0014] To facilitate the connection between the wire rope on the traction device and the traction head, preferably, the traction head is provided with a traction ring, which is integrally formed with the traction head.

[0015] Preferably, the length of the core from the end integrally formed with the traction head to the end away from the traction head is ≥60mm, and the length of the clamp from the top end to the bottom end is ≥40mm.

[0016] To ensure that the clamp can slide a certain distance on the core and improve the installation efficiency of the center wire, preferably, the length of the core from the end integrally formed with the traction head to the distance away from the traction head is 20mm longer than the length from the top end of the clamp to the bottom end of the clamp.

[0017] In order to ensure that the core is clamped tightly and that the clamping length of the core is sufficient to meet the fixing force requirements of the traction and threading process, preferably, in step S3, after the traction force is fully applied, the central axis of the core is aligned with the central axis of the clamp; the distance from the top of the clamp to the top of the core is ≥5mm, and the distance from the bottom of the clamp to the bottom of the core is ≥5mm.

[0018] Preferably, the distance from the top end of the clamp to the top end of the core is 10mm, and the distance from the bottom end of the clamp to the bottom end of the core is 10mm.

[0019] In order to ensure that the formed traction steel strand bundle can effectively pass through the corrugated pipe and reduce the difficulty of traction and strand passing construction, preferably, the bottom outer diameter of the clamp is less than the inner diameter of the corrugated pipe.

[0020] To ensure the traction device can pass smoothly through the bellows, preferably, the absolute difference between the bottom outer diameter of the clamp and the inner diameter of the bellows is 0.5-20 mm. More preferably, the absolute difference between the bottom outer diameter of the clamp and the inner diameter of the bellows is 8 mm.

[0021] To simplify the clamping and installation of the middle wires in the steel strands and improve the stability of the connection during traction, the steel strand clamping assembly preferably includes several wire grooves a on the outer wall of the core and several wire grooves b on the inner wall of the clamp, wherein the wire grooves a and b are mutually matched; the radius of curvature of the wire groove a is greater than or equal to the radius of curvature of the middle wire, and the chord length of the wire groove a is less than the diameter of the middle wire; the radius of curvature of the wire groove b is greater than or equal to the radius of curvature of the middle wire, and the chord length of the wire groove b is less than the diameter of the middle wire; when connecting the bundled steel strands to the threading device, the middle wires are placed one-to-one in the wire grooves a, and then the bottom end of the clamp is sleeved on the core from the traction head end, so that the wire grooves b correspond one-to-one with the wire grooves a, thereby clamping and fixing the middle wires to form a traction steel strand bundle.

[0022] To reduce the probability of the middle wire slipping out of the wire groove a and wire groove b, preferably, the wire groove a is provided with anti-slip texture (a number of core teeth) and / or the wire groove b is provided with anti-slip texture (a number of mating teeth).

[0023] To enhance the continuity of force on the middle wire, preferably, the anti-slip texture in the wire groove a and the anti-slip texture in the wire groove b can be in a circular or spiral structure after the wire groove a and the wire groove b are matched with each other.

[0024] In order to enable the clamp to slide on the core, thereby changing the gap between the wire groove a and the wire groove b, and thus changing the clamping strength of the center wire, preferably, the wire groove b and the wire groove a are matched to form a circular hole.

[0025] Compared with the prior art, the technical effects of this invention are reflected in:

[0026] This invention features a simple construction process. By bundling the bundled steel strands, the center wire is made free. Combined with the clamping action of the clamps and core on the threading device, the center wire is clamped and fixedly connected to the threading device. At the same time, the improved structure of the clamps and core ensures that when the traction device pulls the strand through the corrugated pipe, the clamping force of the clamps on the center wire is enhanced, effectively reducing the center wire from falling off the threading device and improving the efficiency of the entire bundle threading construction. It also avoids the need to hammer and anchor or weld the center wire to the threading device, and the steel strand is not subject to thermal stress, so no further processing is required.

[0027] The threading device used in this invention has a simple structure. Combined with the construction process of this invention, it fully ensures the tight clamping of the wires in the steel strands and ensures that the bundled steel strands are threaded through the corrugated pipe. It avoids the defect of the last few strands being unable to pass through when threading individual steel strands one by one, reduces the construction difficulty, improves the construction efficiency, ensures the quality of threading construction, and reduces costs. Attached Figure Description

[0028] Figure 1 This invention provides a schematic diagram of the prestressed structural steel strand bundle installation operation.

[0029] Figure 2 A schematic diagram of the overall structure of the threading device used in this invention.

[0030] Figure 3 for Figure 2 The arrow indicates a schematic diagram of the view structure.

[0031] Figure 4 for Figure 3 Another embodiment of the structural diagram.

[0032] Figure 5 Figure 1 Assembly structure diagram.

[0033] Figure 6 This is a schematic diagram of the cross-sectional structure of the fixture.

[0034] Figure 7 This is a schematic diagram of the traction core structure.

[0035] Figure 8 This is a schematic diagram of the completed structure of a single steel strand.

[0036] Figure 9 This is a schematic diagram of another embodiment of the processing of a single steel strand.

[0037] Figure 10 This is a colored structural schematic diagram of the traction core used in the production design drawings.

[0038] Figure 11 This is a schematic diagram of the colored structure of a single steel strand used for threading.

[0039] 1-Traction ring 2-Traction head 3-Clamp 4-Core 5-Steel strand clamping assembly 6-Matching teeth 7-Core inner teeth 8-Wire groove a 9-Edge wire 10-Middle wire 11-Wire groove b.

[0040] 3.1 Inner wall of the fixture 4.1 Outer wall of the core 9.1 Outer edge wire 9.2 Inner edge wire Detailed Implementation

[0041] The technical solution of the present invention will be further defined below with reference to the accompanying drawings and specific embodiments, but the scope of protection is not limited to the description.

[0042] like Figure 1 As shown, in some embodiments, the prestressed steel strand bundle threading construction method utilizes the clamping connection of the steel strands to the threading device, specifically including the following steps:

[0043] S1: Based on the design requirements of the prestressed structure, determine the number of steel strand bundles to be used and the number of steel strands in each bundle, and then process the steel strands into cuttings; for example... Figure 7As shown, during the cutting and processing of steel strands, the edge wire 9 at the left end of each steel strand is peeled off and cut off, leaving a middle wire 10. The left end of the middle wire 10 is exposed from the left end of the edge wire 9 for a certain length. The cut and processed steel strands are then bundled into a bundled steel strand, and the bundle is extended to the position of the edge wire 9, so that the middle wire 10 is in a free state. This facilitates the connection of the middle wire 10 to the threading device in subsequent processes, and ensures that all steel strands that need to pass through the corrugated pipe form a whole. This helps to prevent individual steel strands from tangling with each other during the bundling process, which would affect the bundling efficiency and the stress effect of the steel strands in later use. This helps to improve the quality of the steel strand bundled threading corrugated pipe.

[0044] S2: Connect the bundled steel strands to the threading device, and the bundled threading device is equipped with several steel strand clamping assemblies; such as Figure 2 and Figure 3 and Figure 4 and Figure 5 and Figure 6 and Figure 7 As shown, the threading device includes a clamp 3 and a traction core. The traction core includes a traction head 2 and a core body 4. The core body 4 is integrally formed with the traction head 2, ensuring the connection stability between the traction head 2 and the core body 4 and preventing detachment or separation within the threading device. The core body 4 is conical, and the diameter of the end of the core body 4 connected to the traction head 2 is less than the diameter of the end of the core body 4 furthest from the traction head 2. The clamp 3 is conical, and the clamp 3 can insert the traction core through the traction head 2 end into the bottom end of the conical clamp 3, so that the clamp 3 is fitted onto the core body 4. This allows the clamp 3 to slide on the core body 4 and clamp the middle wire 10 when the traction device pulls the traction steel strand bundle, improving the stability and strength of the clamping and ensuring the efficiency of the threading construction. The distance between the inner wall of the clamp 3 and the outer wall of the core body 4 is ≤2mm, for example: 0mm (e.g., ...). Figure 3 As shown, the inner wall 3.1 of the fixture and the outer wall 4.1 of the core are in a close fit (with a gap of 0mm); for example: Figure 4 As shown, the inner wall 3.1 of the clamp and the inner wall 4.1 of the core are separated, with a spacing of 0mm < 2mm, such as 0.2mm, 0.5mm, 0.8mm, 1mm, 1.3mm, 1.5mm, 2mm, etc., and several steel strand clamping assemblies 5 are provided between the inner wall of the clamp 3 and the outer wall of the core 4 to facilitate the clamping and installation of the center wire 10; when the bundled steel strands are connected to the threading device, the center wire 10 is clamped and connected to the steel strand clamping assemblies one by one to form a traction steel strand bundle;

[0045] S3: Pass the traction wire rope on the traction device through the corrugated pipe of the prestressed structure in advance, and then fix the traction wire rope to the traction head 2 on the traction strand bundle; start the traction device, and the traction wire rope drives the traction strand bundle through the corrugated pipe. After the traction is in place, cut the exposed middle wire 10 of the traction strand bundle.

[0046] This method enables all steel strands that need to pass through the corrugated pipe to be bundled together as a whole and then threaded through the corrugated pipe in one go, which improves the construction efficiency of threading steel strands through the corrugated pipe and reduces the construction difficulty.

[0047] like Figure 9 As shown, in some embodiments, in step S1, during the processing of steel strand cutting, the left-end edge wire 9 of each steel strand is peeled off and cut off, leaving a middle wire 10, so that the left end of the middle wire 10 is exposed from the left end of the edge wire 9 for a certain length. The edge wire 9 is peeled off in layers to form a structure as shown in the figure. Figure 9 The inner edge wire 9.2 and outer edge wire 9.1 are shown. The processed steel strands are bundled into a bundle, and after being bundled to the left end of the outer edge wire 9.1, the inner edge wire 9.2 is used for further bundling until it reaches the left end of the inner edge wire 9.2, leaving the middle wire 10 free. This allows the edge wires 9 to be gradually peeled off to form a stepped-reducing inner diameter arrangement, and the different inner diameter edge wire structures are gradually bundled. This ensures that all edge wires 9 on the steel strand form a whole, and also forms a conical structure at one end of the middle wire 10. This improves the effect of the threading device on the bundled steel strand when it is pulled by the traction device, improves the traction threading effect and efficiency, and reduces the overall threading difficulty.

[0048] like Figure 1 and Figure 2 and Figure 3 and Figure 5 and Figure 7 As shown, in some embodiments, the traction head 2 is provided with a traction ring 1, which is integrally formed with the traction head 2. This can effectively improve the connection efficiency and strength between the wire rope on the traction device and the traction head 2, and reduce the difficulty of construction connection.

[0049] In some embodiments, the length of the core 4 from the end integrally formed with the traction head 2 to the distance away from the traction head 2 is ≥60mm, for example, 60mm, 65mm, 70mm, 75mm, 80mm, 90mm, 100mm, 150mm, 200mm, etc., and the length of the clamp 3 from the top end to the bottom end is ≥40mm, for example, 40mm, 45mm, 50mm, 55mm, 60mm, 70mm, 80mm, 90mm, 100mm, 150mm, 200mm, etc.

[0050] In some embodiments, the length of the core 4 from the end integrally formed with the traction head 2 to the distance away from the traction head 2 is 20mm longer than the length from the top end to the bottom end of the clamp 3. For example, the length of the core 4 from the end integrally formed with the traction head 2 to the distance away from the traction head 2 is 60mm, and the length of the clamp 3 from the top end to the bottom end is 40mm. This allows the clamp 3 to have a certain sliding distance on the core 4, facilitating the installation of the center wire 10, while ensuring the strength and stability of the clamp 3 and the core 4 in holding the center wire 10, preventing detachment during the traction and threading process. In some embodiments, the distance from the top end of the clamp 3 to the top end of the core 4 is 10mm, and the distance from the bottom end of the clamp 3 to the bottom end of the core 4 is 10mm.

[0051] In some embodiments, in step S3, after the traction force is fully applied, the central axis of the core 4 is aligned with the central axis of the clamp 3; the distance from the top end of the clamp 3 to the top end of the core 4 is ≥5mm, and the distance from the bottom end of the clamp 3 to the bottom end of the core 4 is ≥5mm.

[0052] In some embodiments, the outer diameter of the bottom end of the clamp 3 is smaller than the inner diameter of the corrugated pipe. This facilitates the entire threading device being passed through the corrugated pipe, reducing the difficulty of threading and improving construction efficiency.

[0053] In some embodiments, the absolute difference between the bottom outer diameter of the clamp 3 and the inner diameter of the corrugated pipe is 0.5-20 mm, for example, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, or 20 mm. This ensures that the traction steel strand bundle can pass through the corrugated pipe as a whole.

[0054] like Figure 5 and Figure 6 and Figure 7As shown, in some embodiments, the steel strand clamping assembly includes a plurality of wire grooves a8 on the outer wall of the core 4 and a plurality of wire grooves b11 on the inner wall of the clamp 3, and the wire grooves a8 and b11 can match each other; the radius of curvature of the wire groove a8 is greater than or equal to the radius of curvature of the middle wire 10, and the chord length of the wire groove a8 is less than the diameter of the middle wire 10; the radius of curvature of the wire groove b11 is greater than or equal to the radius of curvature of the middle wire 10, and the chord length of the wire groove b11 is less than the diameter of the middle wire 10; when connecting the bundled steel strands to the threading device, the middle wires 10 are placed one-to-one in the wire grooves a8, and then the bottom end of the clamp 3 is sleeved on the core 4 from the traction head 2 end, so that the wire grooves b11 correspond one-to-one with the wire grooves a8, thereby clamping and fixing the middle wires 10, thus forming a traction steel strand bundle. This facilitates the installation of the middle wire 10 on the threading device to form a traction steel strand bundle, reducing construction difficulty and improving construction efficiency, while ensuring the strength and stability of the connection between the middle wire 10 and the threading device.

[0055] In some embodiments, the wire groove a8 is provided with anti-slip texture (a plurality of internal core teeth 7, such as...) Figure 7 (as shown) and / or the wire groove b11 is provided with anti-slip texture (a number of mating teeth 6, such as...) Figure 6 (As shown). It can enhance the strength and stability of clamping the middle wire 10, reduce the probability of the middle wire 10 detaching from the threading device, and improve the efficiency and effect of bundle threading.

[0056] In some embodiments, the anti-slip patterns in the wire groove a8 and the wire groove b11 can be arranged in a circular or spiral structure after the wire groove a8 and the wire groove b11 are matched. This can enhance the continuity of force on the center wire 10.

[0057] The wire grooves b11 and a8 match to form a circular hole. This allows the clamp 3 to slide on the core 4, causing a change in the gap between the wire grooves a8 and b11, thereby altering the clamping strength of the center wire 10.

[0058] For any other matters not covered in this invention, reference can be made to existing technology or common knowledge known to those skilled in the art, and conventional technical means can be used to implement them. For example, the method of bundling single steel strands with the center wire 10 stripped from the processing into bundled steel strands; another example is the use of conventional traction equipment such as winches for the traction device; another example is the way the steel wire rope on the traction device is connected to the traction ring 1 or the traction head 2, etc., can all be implemented with reference to existing technology or common knowledge known to those skilled in the art.

[0059] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for constructing prestressed steel strand bundles, characterized in that, The steel strand is connected to the threading device by clamping, specifically including the following steps: S1: According to the requirements of the prestressed structure design, determine the number of steel strand bundles to be used and the number of steel strands in each bundle, and carry out steel strand cutting and processing; when cutting and processing the steel strands, peel off and cut off the edge wire (9) at the left end of each steel strand, leaving a middle wire (10) in the middle, so that the left end of the middle wire (10) is exposed from the left end of the edge wire (9) for a certain length, and bundle the cut steel strands into bundled steel strands, and bundle them to the position of the edge wire (9), so that the middle wire (10) is free; S2: Connect the bundled steel strands to the threading device, and the threading device is provided with several steel strand clamping assemblies (5); the threading device includes a clamp (3) and a traction core, the traction core includes a traction head (2) and a core body (4), the core body (4) and the traction head (2) are integrally formed; the core body (4) is conical, and the diameter of the end of the core body (4) connected to the traction head (2) is less than the diameter of the end of the core body (4) away from the traction head (2); the clamp (3) is conical, and the clamp (3) The traction core can be inserted through the traction head (2) from the bottom end of the conical clamp (3), so that the clamp (3) is sleeved on the core (4); the distance between the inner wall of the clamp (3) and the outer wall of the core (4) is ≤2mm, and a number of steel strand clamping assemblies (5) are provided between the inner wall of the clamp (3) and the outer wall of the core (4); when the bundled steel strands are connected to the threading device, the middle wire (10) is clamped and connected to the steel strand clamping assembly (5) one by one to form a traction steel strand bundle; S3: Pass the traction wire rope on the traction device through the corrugated pipe of the prestressed structure in advance, and then fix the traction wire rope to the traction head (2) on the traction strand bundle; start the traction device, the traction wire rope drives the traction strand bundle through the corrugated pipe, and after the traction is in place, cut the exposed middle wire (10) of the traction strand bundle. Step S3: After the traction force is fully applied, the central axis of the core (4) is aligned with the central axis of the clamp (3); the distance from the top of the clamp (3) to the top of the core (4) is ≥5mm, and the distance from the bottom of the clamp (3) to the bottom of the core (4) is ≥5mm; the steel strand clamping assembly includes several wire grooves a (8) on the outer wall of the core (4) and several wire grooves b (11) on the inner wall of the clamp (3), and the wire grooves a (8) and b (11) can match each other; the radius of curvature of the wire groove a (8) is ≥ the radius of curvature of the middle wire (10). And the chord length of the groove a (8) is less than the diameter of the middle wire (10); the radius of curvature of the groove b (11) is greater than or equal to the radius of curvature of the middle wire (10), and the chord length of the groove b (11) is less than the diameter of the middle wire (10); when connecting the bundled steel strands to the threading device, the middle wires (10) are placed one by one in the groove a (8), and the bottom end of the clamp (3) is sleeved on the core (4) from the end of the traction head (2), so that the groove b (11) corresponds one by one with the groove a (8), thereby clamping and fixing the middle wire (10) to form a traction steel strand bundle.

2. The method for constructing prestressed structural steel strand bundles as described in claim 1, characterized in that, The length of the core (4) from the end integrally formed with the traction head (2) to the distance away from the traction head (2) is ≥60mm, and the length of the clamp (3) from the top end to the bottom end is ≥40mm.

3. The method for constructing prestressed structural steel strand bundles as described in any one of claims 1-2, characterized in that, The length of the core (4) from the end integrally formed with the traction head (2) to the distance away from the traction head (2) is 20 mm longer than the length from the top of the clamp (3) to the bottom of the clamp (3).

4. The method for constructing prestressed structural steel strand bundles as described in claim 1, characterized in that, The distance from the top of the clamp (3) to the top of the core (4) is 10mm, and the distance from the bottom of the clamp (3) to the bottom of the core (4) is 10mm.

5. The method for constructing prestressed structural steel strand bundles as described in any one of claims 1-2 and 4, characterized in that, The outer diameter of the bottom end of the clamp (3) is less than the inner diameter of the bellows.

6. The method for constructing prestressed structural steel strand bundles as described in claim 5, characterized in that, The absolute difference between the bottom outer diameter of the clamp (3) and the inner diameter of the bellows is 0.5-20 mm.

7. The method for constructing prestressed structural steel strand bundles as described in claim 6, characterized in that, The absolute difference between the bottom outer diameter of the clamp (3) and the inner diameter of the bellows is 8 mm.

8. The method for constructing prestressed structural steel strand bundles as described in claim 1, characterized in that, The groove a (8) is provided with anti-slip texture and / or the groove b (11) is provided with anti-slip texture.

Images