Multi-strand steel strand traction device for stay cable of cable-stayed bridge and traction control method

Abstract

The invention belongs to the technical field of bridge construction, and particularly relates to a multi-strand steel strand tractor for a stay cable of a cable-stayed bridge and a traction control method. Comprising a winch; the number of the fixed pulleys I is two; the number of the fixed pulleys II is two; the two groups of cable guide pipes are suspended between the fixed pulley I and the fixed pulley II on the two sides; two ends of the traction steel wire rope respectively penetrate through the two groups of fixed pulleys I, the two groups of fixed pulleys II and the cable guide pipe to form a closed state; the two ends of one steel strand tractor are connected with the two ends of the traction steel wire rope respectively, the other steel strand tractor is installed on the traction steel wire rope, and when one steel strand tractor is fixed to the position, between the left side steel cable guide pipe and the left side cable guide pipe, of the traction steel wire rope, the steel strand tractor is fixed to the position, between the left side steel cable guide pipe and the right side cable guide pipe, of the traction steel wire rope. And the other steel strand tractor is fixed on the traction steel wire rope between the right side tower top fixed pulley and the right side cable guide pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of bridge construction, and in particular is a traction device for multiple steel strands of a cable-stayed cable of a cable-stayed bridge and a control traction method. Background Art

[0002] The commonly used cable-stayed bridge cable steel strand traction device and traction method are: using a circular traction device, through multiple circular traction, the multiple strands of the cable steel strands of the prestressed steel strand bundle of the cable-stayed bridge are gradually inserted into the cable hole on the top of the tower along the inside of the cable guide tube. This method is highly efficient and is particularly suitable for the traction installation of long cable-stayed cables. For example, the existing patent with the public technology application number CN201310678906.4 forms a cyclic traction loop through the winding of the steel wire rope by the steering pulley arranged at the upper and lower ends of the cable-stayed cable and the winch arranged at the bottom of the tower, and realizes the upward traction transmission of the cable steel strand along the hypotenuse direction through the steel strand traction support fixed on the traction steel wire rope in the direction of the cable-stayed cable to assist the installation of the cable-stayed cable at the upper opening.

[0003] However, the circulating traction system and device have the following problems: ① In order to prevent twisting when the steel strand is passed through the hole, the traction device adds two wing plates to occupy the space in the cableway tube. When the inclined cable bundle is installed in the cable guide hole and occupies a certain space, it needs to be removed, and the construction continuity is not strong. ② In order to further ensure the balance of traction and prevent the traction device from twisting, a double-strand traction steel wire rope is used to connect the transmission steel strand with the traction device in the fully closed system, which increases the cost of the traction steel wire rope. ③ Each of the four joints of the double-strand traction steel wire rope and the traction device uses a thrust bearing connection interface and a traction rope connector for disconnection. As long as one of the four traction rope connectors and the four thrust bearing connections is loose or faulty, the stable traction force state of the traction device along the cableway tube will change and twist, affecting the smooth progress of the traction and threading work, and the construction safety is low. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a traction device for multiple steel strands of a cable-stayed bridge cable and a control traction method.

[0005] The present invention adopts the following technical scheme: a traction device for multiple strands of steel strands of a cable-stayed bridge cable, comprising: hoist; A fixed pulley I, wherein two groups of fixed pulleys I are provided, which are respectively provided at the lower ends of the left and right two steel cable guide tubes, and the two ends of the traction wire rope are respectively passed around the left and right two fixed pulleys I; Fixed pulley II, wherein two groups of fixed pulley II are provided, and are respectively arranged at the positions of the steel strands to be installed on the left and right sides of the tower column; A cable guide tube, wherein two groups of the cable guide tubes are provided and are suspended between a fixed pulley I and a fixed pulley II on both sides; A traction wire rope, the traction wire rope is wound on a winch, the winch drives the traction wire rope, and the two ends of the traction wire rope pass through two sets of fixed pulleys I, two sets of fixed pulleys II and a cable guide tube to form a closure; A steel strand traction device, wherein two steel strand traction devices are provided, wherein two ends of one steel strand traction device are respectively connected to two ends of a traction steel wire rope, and the other steel strand traction device is installed on the traction steel wire rope, and when one steel strand traction device is fixed on the traction steel wire rope between the left steel wire rope guide tube and the left cable guide tube, the other steel strand traction device is fixed on the traction steel wire rope between the right tower top fixed pulley and the right cable guide tube; The steel strand can be installed on two steel strand pullers.

[0006] In some embodiments, the strand puller comprises: Arc-shaped steel plate, the front and rear ends of the arc-shaped steel plate are semicircular; A stay cable traction steel block, wherein the stay cable traction steel block is centrally welded on the concave surface of the arc-shaped steel plate; Connecting round steel, two connecting round steels are provided, and are respectively fixed at the front and rear ends of the inclined cable traction steel block; Two groups of slots for clamping the ends of the steel strands are arranged on the traction steel block of the inclined cable.

[0007] In some embodiments, two coaxially arranged nuts are fixed on one side of the inclined cable traction steel block, a directional guide wire rope is passed through the middle of the cable guide tube, one end of the directional guide wire rope is fixed on the tower column, and the other end is fixed on the cable guide tube, and the middle of the directional guide wire rope passes through two coaxially arranged nuts.

[0008] In some embodiments, the card slot includes: A first groove, wherein the first groove is arranged along the upper surface of the inclined cable traction steel block, and the first groove is semi-cylindrical; A second groove, wherein the second groove is arranged along the upper surface of the cable-drawing steel block, and the second groove is connected to one end of the first groove; The third groove is arranged at the end of the second groove and communicated with the second groove, and the third groove is semicircular.

[0009] In some embodiments, two square openings are opened at the intersection of the central axis of the arc-shaped steel plate 8 cm away from the top surfaces of the two end arcs, and the axis direction of the square opening is consistent with the long side direction of the arc-shaped steel plate.

[0010] In some embodiments, the edge of the semicircular arc is tilted 0.5 cm toward the concave direction.

[0011] In some embodiments, the upper end of the cable guide tube is suspended on the tower column by a temporary fixing steel rope of the cable guide tube.

[0012] In some embodiments, the winding method of the traction wire rope is: The traction wire rope passes through the bottom of the left fixed pulley I, and then enters the winding winch from the upper side of the winch. After winding n turns, it passes through the winch from the lower side and passes through the bottom of the fixed pulley I on the right, and then passes through the cable guide tube on the right, the fixed pulley II on the right, the fixed pulley II on the left and the cable guide tube on the left in turn, and then completes the traction loop closure on the left steel strand traction device.

[0013] A method for controlling and traction of a traction device for a cable-stayed bridge with multiple strands of steel strands, comprising the following steps: S1: Install the multi-strand steel strand traction device for the cable-stayed bridge cable; S2: Calculate and determine the length of the traction wire rope; S3: Install the traction wire rope in place and install the steel strand traction device; S4: Install two steel strands on the steel strand puller; S5: The winch is turned on, and the steel strand tractor pulls the two steel strands to the steel strand anchoring station of the inclined cable on the tower. The winch is stopped, and then the steel strands are removed; S6: When the left strand is transported to the right position and parked, the strand tractor on the right arrives at the strand traction installation work surface, and the other two strands are installed on the strand tractor on the right. After confirming that the worker above has removed the wire rope, the winch is controlled to rotate in the opposite direction, and then the wire rope on the right is pulled to the anchoring station of the inclined cable strand on the tower, completing a cycle of traction installation; S7: Repeat the forward and reverse cycles of the winch until the auxiliary installation and traction work of all the steel strands at the cable hole is completed, and then tension and pre-tighten them one by one.

[0014] In some embodiments, step S3 includes: S31: One end of the traction wire rope is temporarily fixed to the top of the wire rope conduit, leaving 1m; S32: The other end of the traction wire rope then passes around the fixed pulley I on the left and comes out from the bottom of the fixed pulley I; and continues to be wound counterclockwise from left to right above the winch turntable; S33: After winding, the end of the traction wire rope is pulled to the fixed pulley I on the right side, and then passes through the bottom and winds out from the top; S34: Tighten both ends of the traction wire rope and clamp the two ends of the traction wire rope with the steel strand traction device using a rope clamp to complete the closing of the traction system.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The steel strand traction device adopts optimized design. Its curved slide plate design and linear transmission arrangement close to the bottom of the cable tube reduce the space occupied by the cable tube and prevent cutting, friction and damage to the cable tube. There is no need to remove parts during the process, which increases the smoothness of transmission and traction.

[0016] There is no need to invest in a double-strand full-circulation closed wire rope, which saves the investment of traction wire rope in directions other than the direction of the cable guide tube in the closed transmission circulation loop.

[0017] Each traction device and the connected traction steel rope are connected in a non-breaking fixation way by using four rope clamps. Even if one part becomes loose, the traction device will not suddenly become loose and fall off. During the process, you only need to check each cycle, which has a high safety factor.

[0018] At the same time, the double-strand rope traction device with optimized design has added a constraint guide nut. Under the spatial constraint of the guide wire rope, it only slides in a straight line along the bottom of the rope guide tube hole. Combined with its curved slide design and the linear transmission arrangement close to the bottom of the rope guide tube, the space occupied by the cable tube is reduced, cutting friction and damage to the rope guide tube are prevented, the smoothness of transmission traction is increased, and entanglement with the rope already passed above is avoided, thereby improving the quality of rope threading.

[0019] Traditionally, when the tractor is fixed on only one traction wire rope, the steel strand will rotate along its circular cross section as the system is driven, causing the tractor fixed on the traction wire rope to rotate around the traction wire rope, which may cause the tractor to get twisted or the rope to be threaded poorly. By fixing the slider with the guide wire rope, the tractor can be prevented from getting twisted when rotating. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of the multi-strand steel strand traction device for the cable-stayed bridge; Figure 2 This is a structural diagram of a steel strand traction device; Figure 3 This is an enlarged view of the location of the steel cable guide of the multi-strand steel strand traction device of the cable-stayed bridge; In the figure, 1- winch, 2- traction wire rope, 3- fixed pulley I, 4- fixed pulley II, 5- tower column, 6- cable guide tube, 7- steel strand traction device, 8- steel strand, 9- temporary fixing steel rope of cable guide tube, 10- directional guide rail wire rope, 11- cable guide tube. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] like Figure 1 As shown, a traction device for multiple steel strands of a cable-stayed bridge cable comprises: Winch 1; Fixed pulleys I3, wherein two groups of fixed pulleys I3 are provided, which are respectively provided at the lower ends of the left and right two steel cable guide tubes 11, and the two ends of the traction wire rope 2 are respectively passed around the left and right two fixed pulleys I3; Fixed pulley II4, wherein two groups of fixed pulley II4 are provided, and are respectively arranged at the positions of the steel strands to be installed on the left and right sides of the tower column 5; Cable guide tubes 6, wherein two groups of cable guide tubes 6 are provided and suspended between fixed pulleys I3 and II4 on both sides; A traction wire rope 2, wherein the traction wire rope 2 is wound on a winch 1, and the winch 1 drives the traction wire rope 2, and both ends of the traction wire rope 2 pass through two sets of fixed pulleys I3, two sets of fixed pulleys II4 and a cable guide tube 6 to form a closed state; Steel strand tractors 7, wherein two steel strand tractors 7 are provided, wherein two ends of one steel strand tractor 7 are respectively connected to two ends of the traction steel wire rope 2, and the other steel strand tractor 7 is installed on the traction steel wire rope 2, and when one of the steel strand tractors 7 is located at the lower end, the other steel strand tractor 7 is located at the position where the steel strand is to be installed; The steel strand 8 can be installed on two steel strand pullers 7.

[0023] The upper end of the cable guide tube 6 is suspended on the tower column 5 through a cable guide tube temporary fixing steel rope 9.

[0024] In some embodiments, the winding method of the traction wire rope 2 is: The traction wire rope 2 passes through the bottom of the left fixed pulley I3, then enters the winding winch 1 from the upper side of the winch 1, and after winding n turns, passes through the winch 1 from the lower side and passes through the bottom of the right fixed pulley I3, and then passes through the right cable guide 6, the right fixed pulley II4, the left fixed pulley II4 and the left cable guide 6 in sequence. This winding method allows the traction wire rope 2 to extend at one end and retract at one end under the drive of the winch 1, realizing the up and down reciprocating motion of the tractor.

[0025] like Figure 2 As shown, the steel strand traction device 7 comprises: The curved steel plate 7.1.1 has a semicircular arc shape at the front and rear ends, and the edge of the semicircular arc is tilted 0.5 cm toward the concave surface; A stay cable traction steel block 7.1.4, wherein the stay cable traction steel block 7.1.4 is centrally welded on the concave surface of the arc-shaped steel plate 7.1.1; The connecting round steel 7.1.3 is provided in two pieces and is respectively fixed at the front and rear ends of the inclined cable traction steel block 7.1.4.

[0026] Two coaxially arranged nuts 7.1.8 are fixed on one side of the inclined cable traction steel block 7.1.4, and a directional guide wire rope 10 is passed through the middle of the cable guide tube 6. One end of the directional guide wire rope 10 is fixed on the tower column 5, and the other end is fixed on the cable guide tube 11. The directional guide wire rope 10 passes through two coaxially arranged nuts 7.1.8 in the middle.

[0027] The inner circular hole wall of the nut 7.1.8 is polished smooth, and the straight line connecting the geometric center of the nut 7.1.8 is parallel to the directional guide wire rope 10.

[0028] The traction device guide wire rope is arranged in each of the cable guide holes on both sides. The upper and lower ends of the directional guide wire rope 10 are fixed and tensioned by hook-type expansion bolts anchored on the beam surface near the cable guide and near the inclined cable hole on the top of the tower column. The directional guide wire rope 10 passes through the coaxial nut hole on the steel block.

[0029] The cable-stayed traction steel block 7.1.4 is provided with two groups of slots for clamping the ends of the steel strands.

[0030] Card slots include: A first groove 7.1.5, which is arranged along the upper surface of the cable-stayed cable traction steel block 7.1.4, and is semi-cylindrical; A second groove 7.1.6, which is arranged along the upper surface of the cable-stayed traction steel block 7.1.4, and is connected to one end of the first groove 7.1.5; The third groove 7.1.7 is arranged at the end of the second groove 7.1.6 and communicated with it. The third groove 7.1.7 is semicircular.

[0031] The arc-shaped steel plate 7.1.1 has two square openings 7.1.2 centered at the intersection of the central axes 8 cm away from the top surfaces of the arcs at both ends, and the axis direction of the square openings 7.1.2 is consistent with the long side direction of the arc-shaped steel plate 7.1.1.

[0032] Specifically, the steel strand tractor is a galvanized steel pipe with an inner diameter of 200mm to 280mm and a wall thickness of 3.5mm. The 34cm long pipe body is cut into a 12cm wide arc steel plate along the central axis of the pipe, and the two ends of the plate are polished into a semicircular arc with a diameter of 12cm. At the same time, the arc edges of the semicircular steel plates at both ends are tilted 0.5cm in the concave direction to prevent the end of the traction plate from being under the cable guide tube and having strong friction and cutting with the tube wall, thereby damaging the guide tube or making the cable traction run unsmoothly.

[0033] The curved steel plate enables it to be close to the lower curved surface of the cable guide tube, reducing the space occupied by the traction device in the tube and ensuring the basic space used to complete the last working lock. At the same time, this design makes it less likely for the steel plate to flip over and turn over when it slides back and forth along the bottom of the tube.

[0034] Further, two 4×4 cm square openings were opened with the intersection of the central axis of the arc-shaped steel plate 8 cm away from the top surface of the arc at both ends as the center, and the axis direction of the square opening was consistent with the long side direction of the steel plate.

[0035] A 16cm long, 6cm wide and 2cm high cable traction steel block is welded in the middle of the concave surface of the steel plate along the long side direction. The long side of the steel block is in the same direction as the side of the traction steel block field, and the four sides of the steel block in contact with the steel plate are welded firmly; Furthermore, a Φ8 round steel with a length of 15 cm is welded to the midline of the plane of the two cross-section ends of the steel block close to the plane of the steel plate. The round steel is firmly welded to the steel plate surface and the contact position of the steel block, and the other end of the steel bar is freely extended.

[0036] The upper surface of the steel block is provided with two semi-cylindrical first grooves with a length of 6 cm and a diameter of 2 cm from one end to the other end along the long side direction, and the distance between the two grooves is 1 cm; Continue upward along the central axis of the long side of the first groove, and a second groove with a length of 5 cm, a width of 0.5 cm, and a depth of 1 cm is provided on the surface of the steel block in line with the central axis of the long side of the first groove, and the first groove is connected to the second groove; Continue to extend upward along the middle axis of the second groove in the long side direction, and the upper surface of the steel block is provided with a semi-cylindrical third groove with a length of 3 cm and a diameter of 1 cm, which is consistent with the middle axis of the second groove in the long side direction. The third groove is connected to the second groove, and the four inner angles of the third groove are 135°. It has a buffering effect on the pier head of the single wire segment of the steel strand to prevent the right angle from causing shear damage to the belly wire under the action of external force.

[0037] Further, when the steel strand traction device is connected with the steel wire rope at the corresponding position of the steel strand bundle multi-hole traction system of the high tower column double cable plane cable-stayed bridge described above, the traction steel wire is at the bottom and is close to the steel plate along the center line of the steel plate, and then the steel wire rope clamp is used to clamp the round steel and the bottom steel wire rope at the 4×4 opening and the steel bars protruding at both ends. Two rope clamps are set at each end to improve safety.

[0038] A method for controlling and traction of a traction device for a cable-stayed bridge with multiple strands of steel strands, comprising the following steps: S1: Install the multi-strand steel strand traction device for the cable-stayed bridge cable; S2: Calculate and determine the length of the traction wire rope 2; S3: Install the traction wire rope 2 in place and install the steel strand traction device 7; S4: Install two steel strands 8 on the steel strand traction device 7; S5: The winch 1 is turned on, and the steel strand tractor 7 pulls the two steel strands 13 to the stay cable steel strand anchoring station on the tower, the winch 1 is stopped, and then the steel strand 8 is removed; S6: When the left steel strand 13 is transported to the position and parked, the right steel strand tractor 7 arrives at the steel strand traction installation working surface, and the other two steel strands 13 are installed on the right steel strand tractor 7. After confirming that the worker above has removed the steel wire rope, the winch 1 is controlled to rotate in the opposite direction, and then the right steel wire rope is pulled to the inclined cable steel strand anchoring station on the tower, completing a cycle of traction installation; S7: Repeat the forward and reverse cycles of winch 1 until the auxiliary installation and traction work of all steel strands at the cable hole is completed, and then tension and pre-tighten each strand.

[0039] In step S2, The length of the traction wire rope 2 is: the winding length L1 of the winch 1 + the horizontal distance L2×2 from the center of the winch 1 to the bottom of the cable duct 11 + the inclined straight-line distance L3 from the cable duct 11 to the cable hole on the same side of the tower top + the center distance L4 of the two fixed pulleys II4 on the tower top + the surplus amount L5.

[0040] Step S3 includes: S31: One end of the traction wire rope 2 is temporarily fixed to the top of the wire rope guide 11, with 1m left; S32: The other end of the traction wire rope 2 then passes around the fixed pulley I3 on ​​the left and comes out from the bottom of the fixed pulley I3; and continues to be wound counterclockwise from left to right above the turntable of the winch 1; S33: After winding, the rope end of the traction wire rope 2 is pulled to the fixed pulley I3 on ​​the right side, passes through the bottom and winds out from the top; S34: Tighten the two ends of the traction wire rope 2 and use a rope clamp to clamp the two ends of the traction wire rope 2 to the steel strand traction device 7 respectively, completing the closing of the traction system.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A traction device for multiple steel strands of a cable-stayed bridge, characterized in that: include: Winch (1); A fixed pulley I (3), wherein two groups of the fixed pulley I (3) are provided and are respectively arranged at the lower ends of the two left and right steel cable guide tubes (11); Fixed pulleys II (4), wherein two groups of fixed pulleys II (4) are provided, and are respectively arranged at positions where the steel strands are to be installed on the left and right sides of the tower column (5); A cable guide tube (6), wherein two groups of the cable guide tube (6) are provided and are suspended between a fixed pulley I (3) and a fixed pulley II (4) on both sides; A traction steel wire rope (2), wherein the traction steel wire rope (2) is wound on a winch (1), and the winch (1) drives the traction steel wire rope (2), and both ends of the traction steel wire rope (2) respectively pass through two sets of fixed pulleys I (3), two sets of fixed pulleys II (4) and a rope guide tube (6) to form a closed state; A steel strand traction device (7), wherein two steel strand traction devices (7) are provided, wherein two ends of one of the steel strand traction devices (7) are respectively connected to two ends of the traction steel wire rope (2), and the other steel strand traction device (7) is installed on the traction steel wire rope (2); when one of the steel strand traction devices (7) is fixed to the traction steel wire rope between the left steel wire rope guide tube and the left cable guide tube, the other steel strand traction device (7) is fixed to the traction steel wire rope between the right tower top fixed pulley and the right cable guide tube; A steel strand (8), wherein the steel strand (8) can be installed on two steel strand pullers (7).

2. The cable-stayed bridge cable multi-strand steel strand traction device according to claim 1, characterized in that: The steel strand traction device (7) comprises: Arc steel plate (7.1.1), the front and rear ends of the arc steel plate (7.1.1) are semicircular; A cable-stayed traction steel block (7.1.4), wherein the cable-stayed traction steel block (7.1.4) is centrally welded on the concave surface of the arc-shaped steel plate (7.1.1); Connecting round steel (7.1.3), wherein two connecting round steels (7.1.3) are provided and are respectively fixed at the front and rear ends of the inclined cable traction steel block (7.1.4); The cable-stayed traction steel block (7.1.4) is provided with two sets of slots for clamping the ends of the steel strands.

3. The cable-stayed bridge cable multi-strand steel strand traction device according to claim 2, characterized in that: Two coaxially arranged nuts (7.1.8) are fixed on one side of the inclined cable traction steel block (7.1.4), and a directional guide wire rope (10) is passed through the middle of the cable guide tube (6). One end of the directional guide wire rope (10) is fixed to the tower column (5), and the other end is fixed to the cable guide tube (11). The middle of the directional guide wire rope (10) passes through the two coaxially arranged nuts (7.1.8).

4. The cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 2, characterized in that: The card slot comprises: A first groove (7.1.5), the first groove (7.1.5) being arranged along the upper surface of the inclined cable traction steel block (7.1.4), the first groove (7.1.5) being semi-cylindrical; A second groove (7.1.6), the second groove (7.1.6) being arranged along the upper surface of the inclined cable traction steel block (7.1.4), the second groove (7.1.6) being connected to one end of the first groove (7.1.5); A third groove (7.1.7), the third groove (7.1.7) is arranged at the end of the second groove (7.1.6) and is connected thereto, and the third groove (7.1.7) is semicircular.

5. The cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 2, characterized in that: The arc-shaped steel plate (7.1.1) has two square openings (7.1.2) centered at the intersection of the central axis 8 cm away from the top surfaces of the two end arcs, and the axis direction of the square openings (7.1.2) is consistent with the long side direction of the arc-shaped steel plate (7.1.1).

6. The cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 2, characterized in that: The edge of the semicircular arc is tilted 0.5 cm toward the concave surface.

7. The cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 1, characterized in that: The upper end of the cable guide tube (6) is suspended on the tower column (5) via a cable guide tube temporary fixing steel rope (9).

8. The cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 1, characterized in that: The winding method of the traction wire rope (2) is: The traction wire rope (2) passes through the bottom of the left fixed pulley I (3), then enters the winding winch (1) from the upper side of the winch (1), and after winding n turns, passes through the winch (1) from the lower side and passes through the bottom of the right fixed pulley I (3), and then passes through the right rope guide tube (6), the right fixed pulley II (4), the left fixed pulley II (4) and the left rope guide tube (6) in sequence, and then completes the traction circuit closure on the left steel strand traction device (7).

9. A control and traction method for a cable-stayed bridge cable-stayed cable multi-strand steel strand traction device according to claim 1, characterized in that: The following steps are involved: S1: Install the multi-strand steel strand traction device for the cable-stayed bridge cable; S2: Calculate and determine the length of the traction wire rope (2); S3: Install the traction wire rope (2) in place and install the steel strand traction device (7); S4: installing two steel strands (8) on the steel strand traction device (7); S5: The winch (1) is turned on, and the steel strand traction device (7) pulls the two steel strands (13) to the inclined cable steel strand anchoring station on the tower, the winch (1) is stopped, and then the steel strands (8) are removed; S6: When the left steel strand (8) is transported to the position and stops, the right steel strand tractor (7) arrives at the steel strand traction installation working surface, and the other two steel strands (8) are installed on the right steel strand tractor (7). After confirming that the worker above has removed the steel wire rope, the winch (1) is controlled to rotate in the opposite direction, and then the right steel wire rope is pulled to the inclined cable steel strand anchoring station on the tower, completing a cycle of traction installation; S7: Repeat the forward and reverse cycles of the winch (1) until the auxiliary installation and traction work of all the steel strands at the cable hole positions is completed, and then tension and pre-tighten each strand.

10. The control and traction method of the traction device for the multiple strands of the cable-stayed bridge cable according to claim 8, characterized in that: The step S3 comprises: S31: One end of the traction wire rope (2) is temporarily fixed to the top of the wire rope guide (11), with 1m left; S32: The other end of the traction wire rope (2) then passes around the fixed pulley I (3) on the left and comes out from the bottom of the fixed pulley I (3); and continues to be wound counterclockwise from left to right above the rotating disk of the winch (1); S33: After winding, the end of the traction wire rope (2) is pulled to the fixed pulley I (3) on the right side, and then passes through the bottom and winds out from the top; S34: tightening the two ends of the traction steel wire rope (2) and clamping the two ends of the traction steel wire rope (2) with the steel strand traction device (7) respectively using a rope clamp, thereby completing the closing of the traction system.

Images