A construction method for replacing stay cables of a low tower cable-stayed bridge with anti-slip anchoring devices

Abstract

The present invention relates to a construction method for replacing stay cables of a low tower cable-stayed bridge with anti-slip anchoring devices, mainly including construction stages: construction preparation work; treatment of the operation window of the old cable; arrangement of cable replacement construction equipment; relaxation and unloading of the steel strands of the old cable; extraction and unloading of the steel strands of the old cable, introduction of tool steel strands; cleaning of the anchor cone holes; penetration and tensioning of the new steel strands; repeating the above steps 4 to 7 until the replacement of all the steel strands of the cable is completed; resetting and installation of components, anti-corrosion treatment. By introducing a temporary steel strand with an auxiliary function, the technical problems of traction and guidance for the penetration and guidance of the new steel strands are solved.

Description

Technical Field

[0001] The present invention relates to a construction method for replacing stay cables of a low tower cable-stayed bridge, and more particularly to a construction method for replacing single steel strands of stay cables of a low tower cable-stayed bridge with an anti-slip anchoring device. Background Art

[0002] A low tower cable-stayed bridge is also called a partial cable-stayed bridge. The steel strands of the stay cables are continuously and uninterruptedly pre-buried through the saddle of the main tower, and both ends of the steel strands are anchored on the main girder. The overall structure of the stay cable is as Figure 1 shown. Both ends of the stay cable are anchored on the main girder. The beam-end anchor is of the structure of a steel strand wedge-type group anchor, that is, each steel strand is clamped by a wedge. The inside of the anchor is filled with a non-bonded and non-cured filling material. To prevent the stay cable from slipping due to unbalanced forces on both sides of the main tower, an anti-slip anchoring device is generally provided at one end of the saddle of the bridge tower.

[0003] When replacing the stay cable of a low tower cable-stayed bridge with an anti-slip anchoring device, the following technical problems exist:

[0004] 1) There are wire dividing pipe saddles pre-buried on the bridge tower of the low tower cable-stayed bridge. An anti-slip anchoring sleeve with a diameter larger than the inner diameter of the wire dividing pipe of the saddle is fixedly arranged on the steel strand. Therefore, the original steel strands of the stay cable cannot pass through the wire dividing pipe saddle throughout the length, and the original steel strands cannot perform the function of guiding and traction.

[0005] 2) An anti-slip block is also provided on one side of the stay cable of the low tower cable-stayed bridge where the anti-slip anchoring device is arranged. The anti-slip block is composed of a plurality of layered insertion plates stacked together. The layered insertion plates fix the steel strands in layers, that is, the steel strands are fixed between two adjacent layered insertion plates. The anti-slip block blocks and fixes the steel strands to prevent the steel strands from slipping during service, but when the stay cable needs to be replaced, the anti-slip block must be removed, and it is removed under the state that the original steel strands are under the operating cable force.

[0006] 3) When using the method of replacing single steel strands of the stay cable, only the steel strands and wedges are replaced without replacing the anchor. The anchor cone hole of the anchor needs to be cleaned to ensure the reliable anchoring quality of the new steel strands and wedges and ensure the safe use of the new stay cable after replacement. Summary of the Invention

[0007] The purpose of the present invention is to provide a construction method for replacing single steel strands of the stay cable of a low tower cable-stayed bridge with an anti-slip anchoring device for the above-mentioned existing technology, and a construction method that ensures the anchoring quality.

[0008] The method of the present application can realize the single-strand replacement of the stay cable steel strands under the condition of using small and lightweight construction tools, achieve the purpose of replacing the stay cable, and extend the service life of the bridge.

[0009] The technical solution adopted by the present invention to solve the above problems is as follows: A construction method for replacing the stay cables of a low tower cable-stayed bridge with anti-slip anchoring devices, including the following steps,

[0010] I. Construction preparation: Set up an operation platform and prepare construction tools;

[0011] II. Treatment of the old cable operation window:

[0012] 2.1 Tower end operation window

[0013] Dismantle the anti-slip anchoring cylinders on both sides of the wire dividing pipe saddle at the bridge tower, lower the anti-slip anchoring cylinders and the extension pipes outside the stay cables by a certain distance together, so that the stay cables on both sides of the wire dividing pipe saddle are exposed, and the exposed length is generally not less than 1.0 m; Remove the tower end cable clamps on the stay cables;

[0014] Remove the anti-slip blocks on the steel strands on the left side of the wire dividing pipe saddle, so that the steel strands can be pulled to the left without hindrance, that is, in the direction of the side where the anti-slip blocks are installed on the stay cables. Since the anti-slip anchoring sleeves are fixed on the left steel strands, the steel strands cannot be pulled to the right;

[0015] 2.2 Beam surface operation window

[0016] Release the connection between the embedded pipes and the waterproof covers at the anchoring positions on both sides of the old stay cable, lift the waterproof covers and the outer sleeves outside the stay cables upward together to expose the stay cables at the upper ends of the embedded pipes. The exposed length of the beam end stay cables is not less than 1.0 m. Remove the beam end cable clamps and beam end shock absorbers installed on the stay cables, if any;

[0017] 2.3 Beam end anchoring end operation window

[0018] Remove the protective cover at the end of the embedded pipe to expose the ends of the steel strands and clean the steel strands;

[0019] III. Arrangement of cable replacement construction equipment:

[0020] Arrange a wire reel and a cable conveying and threading machine near the exposed stay cables at the beam end, and prepare temporary steel strands with sufficient length;

[0021] IV. Relaxation and unloading of the old cable steel strands:

[0022] Install jack tensioning tools on the anchor fittings at both ends of the stay cable respectively, relax and unload the two ends of the single steel strand to be replaced to zero, and remove the anchoring clip pieces of the steel strand in the anchor fitting;

[0023] V. Withdrawal and unloading of the old cable steel strands and introduction of temporary steel strands:

[0024] 5.1 Connect the guiding rod

[0025] At the beam end of the cable, guide rods are connected to the two ends of the same old strand to be replaced;

[0026] 5.2 Pull the two ends of the old steel strand out of the anchorage section

[0027] Lift the two ends of the steel strand separately in the operation window on the beam surface, pull the steel strand completely out of the anchor to the outside of the embedded pipe, and at the same time, insert the guide rod into the anchor and embedded pipe along with the steel strand until the embedded pipe is exposed, separate the guide rod from the steel strand, and leave the guide rod in the embedded pipe for standby use;

[0028] 5.3 Connection of facilities for removing old steel strands

[0029] The left end of the old steel strand pulled above is used as the traction end, and is wound onto the left reel through the left conveying and threading machine, and the right end of the old steel strand is connected to the temporary steel strand;

[0030] 5.4 Removal of old steel strands

[0031] Driven by the old steel strand, the temporary steel strand is led along the path of the old steel strand to the left beam operation window, so that the old steel strand is separated from the temporary steel strand, and the old steel strand is completely removed from the inclined cable, and the introduction of the temporary steel strand is completed;

[0032] 6. Anchor cone hole cleaning:

[0033] At the operating windows on the beam surfaces on both sides, lift the guide rod until the lower end of the guide rod leaves the anchor hole of the anchor, and clean the anchor hole from the end of the anchor;

[0034] 7. Insertion and tensioning of new steel strands:

[0035] 7.1 Insertion of new steel strand

[0036] Place the new steel strand on the left reel, lead the end out and pass it through the left conveying and threading machine, connect the new steel strand with the temporary steel strand end to end through the left beam surface operation window, pull the temporary steel strand in the opposite direction from the right, and convey the new steel strand to the right along with the temporary steel strand, and introduce it from the left beam surface operation window in turn, along the path of the old steel strand until the right beam surface operation window, at this time, confirm that the anti-slip anchor sleeve (16) on the new steel strand also reaches the end face of the wire distribution tube saddle (18), so that the new steel strand is inserted and the new steel strand is separated from the temporary steel strand (25);

[0037] 7.2 New steel strand inserted into anchor

[0038] At the operating window on the beam surface, connect the two ends of the new steel strand to the guide rods reserved in the embedded pipe respectively, and under the guidance of the guide rods, pass the new steel strand through the anchor hole of the old steel strand of the anchor;

[0039] 7.3 Tensioning of new steel strands

[0040] Install new wedges in the anchor holes at both ends of the new steel strands, and tension the new steel strands until the designed cable force is reached. Thus, the replacement of one steel strand is completed;

[0041] VIII. Repeat steps 4 to 7 above until the replacement of all steel strands of the stay cables is completed;

[0042] IX. Component reset installation and anti-corrosion treatment:

[0043] Install anti-slip blocks on the new stay cable steel strand bundles, and restore the anti-slip anchoring cylinder, tower end operation window, beam surface operation window, and beam end anchoring end operation window. Thus, the replacement of the stay cables is completed, and the remaining stay cables of the cable-stayed bridge can be replaced in sequence according to the above scheme and steps.

[0044] As one of the implementation manners of this case, in step 2.1, a separating pin is used to assist in disassembling the anti-slip block. The anti-slip block is composed of several layers of laminated plates. The separating pin is inserted between the upper and lower rows of steel strands of the laminated plates at a position adjacent to the anti-slip block. The separating pin separates the upper and lower rows of steel strands, and the separation distance p is greater than the thickness m of the laminated plate, so as to take out the laminated plate. In this way, all the laminated plates are taken out layer by layer, thereby realizing the disassembly of the anti-slip block and enabling the steel strands to be pulled out to the left without obstruction.

[0045] As one of the implementation manners of this case, in step 5.2, a lifting drag hook is set near the beam surface operation window. The separating pin is inserted into the layer where the old steel strand is located to leave a lifting space, and the old steel strand that has been released and unloaded is lifted, and the end of the old steel strand is pulled out of the anchor until it is pulled out outside the embedded pipe.

[0046] Preferably, in step six, at the beam surface operation window, the previously introduced guiding rod is lifted until the lower end of the guiding rod retracts into the anchor to expose the anchor cone hole, and a cleaning rod is inserted from the end of the anchor into the anchor hole to clean the surface of the anchor cone hole with a cleaning cone head, so as to achieve the purpose of cleaning the anchor cone hole of the anchor.

[0047] Specifically, the following operations are adopted in step nine:

[0048] 9.1 Insert a separating pin between the upper and lower adjacent rows of steel strands to separate the upper and lower adjacent rows of steel strands, and re-insert the laminated plates of the anti-slip block. In this way, layer by layer separation and layer by layer reset of each layer of laminated plates are carried out, thereby realizing the reset of the anti-slip block;

[0049] 9.2 Re-install the pressure-bearing nut 14 and the anti-slip anchoring cylinder 17;

[0050] 9.3 Reset and install the tower end cable hoop, move up the extension pipe, and the tower end operation window is reset and closed;

[0051] 9.4 Reset and install the cable clamp at the beam end and the shock absorber at the beam end, lower the outer casing pipe and the waterproof cover, and reset and close the operation window on the beam surface;

[0052] 9.5 Conduct anti-corrosion treatment on the anchor and the end of the steel strand, reset the protective cover component, and reset and close the operation window at the anchorage end of the beam end.

[0053] For some of the implementation steps described in the present invention, on the premise that the sequence does not affect the achievement of the implementation purpose, the step sequence can be appropriately adjusted according to the actual situation.

[0054] The technical solution of the present invention has the following advantages and beneficial effects:

[0055] (1) The main cable replacement construction facilities of this solution are arranged on the bridge deck, which is convenient for carrying out construction operations;

[0056] (2) Introduce a steel strand as a temporary steel strand, which solves the technical problems of traction and guidance for the penetration of the new steel strand;

[0057] (3) Solve the technical problem of cleaning the anchor cone hole before the new steel strand penetrates into the anchor, and ensure the anchorage quality after the replacement of the stay cable steel strand. Description of the Drawings

[0058] Figure 1 It is a schematic diagram of the stay cable structure of a low tower cable-stayed bridge with an anti-slip anchoring device;

[0059] Figure 2 It is a schematic diagram of the treatment of the old cable operation window before cable replacement construction;

[0060] Figure 3 It is Figure 2 The partial enlarged view of part E in

[0061] Figure 4 It is Figure 3 The D-D view in

[0062] Figure 5 It is Figure 3 The schematic diagram of the insertion of the separating pin at the C part of the steel strand bundle in

[0063] Figure 6 It is the operation schematic diagram of the disassembly or installation of the layered inserts;

[0064] Figure 7 It is the three-dimensional schematic diagram demonstrating the separation of the steel strand, the disassembly or installation of the anti-slip block inserts;

[0065] Figure 8 It is the schematic diagram of the layout of the cable replacement construction facilities;

[0066] Figure 9 It is the construction schematic diagram of the extraction and unloading of the old cable steel strand and the introduction of the tool steel strand;

[0067] Figure 10 is Figure 9 a partial enlarged view of part E;

[0068] Figure 11 is a construction schematic diagram for the penetration of new steel strands;

[0069] In the figure: 1 main tower of the bridge, 2 main beam, 3 anchor, 4 anchoring clip, 5 protective cover, 6 embedded pipe, 7 beam-end shock absorber, 8 beam-end cable clamp, 9 waterproof cover, 10 old steel strand, 11 outer sleeve pipe, 12 extension pipe, 13 tower-end cable clamp, 14 pressure-bearing nut, 15 anti-slip block, 151 layered insertion plate, 16 anti-slip anchoring sleeve, 17 anti-slip anchoring cylinder, 18 wire-splitting pipe saddle, 19 left pay-off and take-up reel, 20 left cable conveyor and penetrator, 21 right cable conveyor and penetrator, 22 right pay-off and take-up reel, 23 lifting and pulling tool, 24 guiding rod, 25 temporary steel strand, 26 new steel strand, 27 cleaning rod, 271 cleaning cone head, 28 separating pin. Specific implementation manners

[0070] The following further describes the present invention in detail with reference to the accompanying drawings. The embodiments are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0071] The overall structure of the stay cable of the low tower cable-stayed bridge with an anti-slip anchoring device is as Figure 1 shown. Among them, the anti-slip anchoring cylinder 17 provided with anti-slip members (pressure-bearing nut 14, anti-slip block 15, anti-slip anchoring sleeve 16) is located on the Figure 1 left side (side A in the figure) of the wire-splitting pipe saddle 18 in the stay cable system shown. There are no anti-slip members inside the anti-slip anchoring cylinder 17 on the right side (side B in the figure) of the wire-splitting pipe saddle 18.

[0072] For the construction method of replacing the stay cable of the low tower cable-stayed bridge with an anti-slip anchoring device, the implementation scheme and operation steps are as follows:

[0073] 1. Construction preparation work

[0074] The construction preparation work includes setting up an operation platform and preparing construction tools.

[0075] 1) Setting up an operation platform

[0076] Set up operation platforms on both sides of the wire-splitting pipe saddle 18 of the main tower 1 of the bridge. If necessary, operation platforms also need to be set up at the beam-end anchors 3 of the stay cables on the left and right sides.

[0077] 2) Preparing construction tools

[0078] The tools for cable replacement construction include a cable reel, a cable conveyor and threading machine, temporary steel strands 25, a guiding rod 24, a separating pin 28 for separating upper and lower rows of steel strand bundles, a jack tensioning tool and a hydraulic oil pump, a chain block and other commonly used auxiliary tools for construction.

[0079] 2. Treatment of the old cable operation window

[0080] To replace the old steel strands 10 of the target stay cable, the following preparatory work is carried out:

[0081] 1) Tower end operation window

[0082] As Figure 2 shown, disassemble the anti-slip anchoring cylinder 17 connected to the left and right end faces of the wire dividing pipe saddle 18, and let it and the extension pipe 12 connected thereto descend along the outer sleeve pipe 11 for a proper distance, so that the stay cable corresponding to the original anti-slip anchoring cylinder 17 exposes a tower end operation window L2 with a length of not less than 1.0 m; disassemble the tower end cable clamp 13 on the old cable;

[0083] As Figures 3 to 7 shown, the anti-slip block 15 of the stay cable is composed of multiple layered inserts 151. To replace the steel strands of the stay cable, the anti-slip block 15 must be disassembled first. At Figure 3 the C shown, use the separating pin 28 to approach the anti-slip block 15 and insert it into the layer where the layered insert 151 is located by hydraulic or mechanical means. The maximum diameter of the separating pin 28 is p. Separate the upper and lower adjacent rows of steel strands of the stay cable. When the separation distance p is greater than the thickness m of the layered insert 151 of the anti-slip block, it provides space for removing the layered insert 151. At this time, the layered insert 151 can be smoothly removed. In this way, layer by layer separation is carried out to remove the layered insert 151 of each layer, so as to realize the disassembly of the anti-slip block 15.

[0084] 2) Beam surface operation window

[0085] As Figure 2 shown, disassemble the connection between the embedded pipe 6 and the waterproof cover 9, lift the waterproof cover 9, the outer sleeve pipe 11 and the waterproof cover 9, so that the stay cable exposes a beam surface operation window L1 with a length of not less than 1.0 m above the pipe orifice of the embedded pipe 6; disassemble the beam end cable clamp 8 and the beam end shock absorber 7 of the old cable.

[0086] 3) Main beam anchorage end operation window

[0087] As Figure 2 shown, disassemble the protective cover 5 at the end of the beam end anchor 3 of the stay cable, let the reserved steel strands at the end be exposed, clean the steel strands at this place, and remove the original anti-corrosion materials and other adhesives.

[0088] 3. Layout of cable replacement construction facilities

[0089] As Figure 8As shown in the figure, arrange the left wire pay-off and take-up reel 19, the left wire conveyor and threading machine 20, the right wire conveyor and threading machine 21, and the right wire pay-off and take-up reel 22 at appropriate positions on the bridge deck, and prepare enough length of temporary steel strands 25 for traction. The temporary steel strands are pre-sleeved on the right wire pay-off and take-up reel 22.

[0090] 4. Loosening and unloading the force of the old cable steel strands

[0091] Install jack tensioning tools on the anchors 3 at both ends of the stay cable, loosen and unload the force at both ends of the same old steel strand 10 to be replaced to zero, and remove the original anchoring clamping pieces 4 on the steel strand.

[0092] 5. Withdrawing and unloading the old cable steel strands and introducing the tool steel strands

[0093] 1) Connect the guiding rod

[0094] As Figure 3 shown in the figure, connect the guiding rods 24 to the ends of both ends of the same old steel strand 10 to be replaced at the beam end of the stay cable.

[0095] 2) Lift the old cable steel strands out of the anchorage section

[0096] As Figure 3 shown in the figure, set up lifting and pulling tools 23 (engineering hooks) near the beam surface operation window L1 on the A side and the B side. Use the separating pin 28 to separate the released and unloaded old steel strand 10 and lift it with the lifting and pulling tool 23. Pull out the left old steel strand 10 from the anchor 3 until it is pulled out of the embedded pipe 6, and at the same time, the guiding rod 24 is also pulled out until the front end is exposed outside the embedded pipe 6. Then separate the guiding rod 24 from the end of the old steel strand 10 and temporarily fix the end of the guiding rod 24 at the port of the embedded pipe 6 for use. Complete the pulling out of both ends of the old steel strand 10 from the beam surface operation window L1.

[0097] 3) Connect the facilities for withdrawing the old steel strands

[0098] The connection method of the facilities for withdrawing the old steel strands 10 is shown in Figure 9 the figure.

[0099] Take the end of the above-mentioned lifted old steel strand 10 as the traction end, wind it on the left wire pay-off and take-up reel 19 through the left wire conveyor and threading machine 20; connect the other end of the old steel strand 10 to the end of the temporary steel strand 25. The temporary steel strand 25 passes through the right wire conveyor and threading machine 21 and is released from the right wire pay-off and take-up reel 22.

[0100] 4) Withdraw the old steel strands

[0101] The left conveying and threading machine 20 and the right conveying and threading machine 21 are started, and the old steel strand 10 is transported to the left take-up and pay-off drum 19 under the traction of the left conveying and threading machine 20. The temporary steel strand 25, driven by the old steel strand 10, passes through the outer casing 11, the wire pipe saddle 18, and the bridge main tower 1 to reach the outer casing 11 section and the beam surface operation window L1, so that the old steel strand 10 can be separated from the temporary steel strand 25. At this point, the old steel strand 10 is removed and the temporary steel strand 25 is introduced.

[0102] 6. Cleaning of anchor cone holes

[0103] like Figure 9 , Figure 10 As shown, in the beam surface operation window L1 on the A side and the B side, the guide rod 24 that has been introduced above is lifted until the lower end of the guide rod 24 is retracted into the anchor 3 to expose the anchor cone hole, and a cleaning rod 27 is inserted into the anchor cone hole and rotated, and the surface of the anchor cone hole is wiped with the cleaning cone head 271 to achieve the purpose of cleaning the anchor cone hole.

[0104] 7. Insertion and tensioning of new steel strands

[0105] 1) Insertion of new steel strand

[0106] The connection method of the new steel strand 26 is shown in Figure 11 shown.

[0107] The new steel strand 26 is placed on the left reel 19, and its end is led out and connected to the end of the temporary steel strand 25 through the left conveying and threading machine 20, and the left conveying and threading machine 20 and the right conveying and threading machine 21 are started synchronously. Under the traction of the temporary steel strand 25, the new steel strand 26 is introduced into the cable from the A-side beam surface operation window L1, and goes up along the outer casing section 11, passes through the wire pipe saddle 18, and along the outer casing section 11 on the other side (B side) of the main tower until the other side (B side) The beam surface operation window L1, the new steel strand is reversely threaded along the path of the old steel strand. At this time, the anti-slip anchor sleeve 16 on the new steel strand 26 also reaches the end face of the wire pipe saddle 18. At this point, the new steel strand 26 is inserted. The new steel strand 26 is separated from the temporary steel strand 25 at the beam surface operation window on the B side.

[0108] 2) New steel strands are inserted into anchors

[0109] In the beam surface operation windows on the A and B sides, the two ends of the new steel strand 26 are respectively connected to the ends of the guide rod 24 that have been introduced above, and under the guidance of the guide rod 24, the new steel strand 26 is passed down into the anchoring holes of the embedded pipe 6 and the original old steel strand 10 of the anchor 3.

[0110] 3) Tensioning of new steel strands

[0111] Install new wedges into the anchor holes of the anchorages 3 at both ends of the new steel strand 26, install the jack tensioning equipment, start the oil pump for tensioning, and tension until the designed cable force is reached. Thus, the replacement of one steel strand is completed.

[0112] 8. Repeat the operations in steps 4 - 7 above until the replacement of all the steel strands of the entire cable is completed.

[0113] 9. Reinstall the components and perform anti-corrosion treatment

[0114] 1) Reinstall the aforementioned anti-sliding retaining block 15 that has been disassembled. The installation method is as Figures 3 to 7 shown. At the position C (i.e., the position close to the anti-sliding retaining block 15) as Figure 3 shown, use hydraulic or mechanical means to insert the separating rod 28 into the steel strand to make it stratified. The diameter of this separating rod is p. Separate the steel strands in adjacent rows of the stay cable above and below. When the separation distance p is greater than the thickness m of the layered insertion plate 151 of the anti-sliding retaining block, the layered insertion plate 151 can be inserted. In this way, layer by layer separation is carried out, and the layered insertion plate 151 of each layer is reinstalled, so as to realize the reinstallation of the anti-sliding retaining block 15.

[0115] 2) Complete the reinstallation of the anti-sliding anchoring components such as the bearing nut 14 and the anti-sliding anchoring cylinder 17;

[0116] 3) Reinstall the tower end components, including installing the tower end cable clamp 13, the upward extended pipe 12, the anti-sliding anchoring cylinder 17, etc. The tower end operation window L2 is reset and closed;

[0117] 4) Reinstall the beam end cable clamp 8 and the beam end shock absorber 7 components, lower the outer sleeve pipe 11 and the waterproof cover 9, and the beam surface operation window L1 is reset and closed;

[0118] 5) Perform anti-corrosion treatment on the beam end anchorage 3 and the reserved steel strand, and reinstall components such as the end anchorage protective cover 5. The main beam anchorage end operation window is reset and closed.

[0119] Thus, the replacement of one entire stay cable is completed, and the replacement of the remaining stay cables of the cable-stayed bridge can be carried out in sequence according to the above scheme and steps.

[0120] In addition to the above embodiments, the present invention also includes other implementation manners. Any technical solutions formed by equivalent transformation or equivalent substitution shall fall within the protection scope of the claims of the present invention.

Claims

1. A construction method for replacing the cable of a low-tower cable-stayed bridge with an anti-slip anchor device. Features: The following steps are included:

1. Construction preparation: setting up the operating platform and preparing construction tools; 2. Old search operation window processing: 2.1 Tower end operation window The anti-slip anchor tubes (17) on both sides of the wire tube cable saddle (18) at the bridge tower are removed, and the anti-slip anchor tubes (17) and the extension tubes (12) outside the inclined cables are lowered for a distance, so that the inclined cables on both sides of the wire tube cable saddle (18) are exposed, and the length of the exposed section is not less than 1.0 m; the tower end cable clamps (13) on the inclined cables are removed; Remove the anti-slip stopper (15) on the left side of the steel strand of the wire tube saddle (18), so that the steel strand can be pulled to the left without hindrance, that is, pulled in the direction of the side where the anti-slip stopper is installed on the inclined cable. Since the anti-slip anchor sleeve (16) is fixed on the left side of the steel strand, the steel strand cannot be pulled to the right; 2.2 Beam surface operation window The connection between the embedded pipe (6) and the waterproof cover (9) at the anchoring positions on both sides of the old inclined cable is released, and the waterproof cover (9) and the outer sleeve (11) outside the inclined cable are lifted upward together to expose the inclined cable at the upper end of the embedded pipe (6), and the exposed length of the beam end inclined cable is not less than 1.0 m. The beam end cable clamp (8) and the beam end vibration damper (7) installed on the inclined cable are removed; 2.3 Beam end anchorage end operation window The protective cover (5) at the end of the embedded pipe (6) is removed to expose the end of the steel strand, and the steel strand is cleaned; 3. Equipment layout for cable replacement: Arrange the pay-off and take-up drums and the cable conveyor near the exposed stay cables at the beam ends, and prepare temporary steel strands of sufficient length; 4. Release the tension of the old cable strand: Installing jack tensioning equipment on the anchors (3) at both ends of the inclined cable respectively, releasing the tension at both ends of the single steel strand to be replaced to zero, and removing the anchoring clip (4) on the steel strand in the anchor (3); 5. Removal of old cable strands and introduction of temporary strands: 5.1 Connecting the guide rod At the beam end of the inclined cable, guide rods (24) are respectively connected to the two ends of the same old steel strand to be replaced; 5.2 Pull the two ends of the old steel strand out of the anchorage section At the operating window on the beam surface, the two ends of the steel strand are respectively pulled up to completely pull the steel strand out of the anchorage to the outside of the pre-buried pipe, and at the same time, the guide rod (24) is also inserted into the anchorage (3) and the pre-buried pipe (6) along with the steel strand until the pre-buried pipe (6) is exposed, and the guide rod (24) is separated from the steel strand, and the guide rod (24) is left in the pre-buried pipe for standby use; 5.3 Connection of facilities for removing old steel strands The left end of the pulled old steel strand is used as the traction end, and is wound onto the left reel (19) through the left conveying and threading machine (20), and the right end of the old steel strand is connected to the temporary steel strand (25); 5.4 Removal of old steel strands The temporary steel strand (25) is driven by the old steel strand and guided along the path of the old steel strand to the left beam surface operation window, so that the old steel strand is separated from the temporary steel strand (25), and the old steel strand is completely removed from the inclined cable, and the introduction of the temporary steel strand (25) is completed; 6. Anchor cone hole cleaning: At the operating windows on the beam surfaces on both sides, the guide rod (24) is lifted up until the lower end of the guide rod (24) leaves the anchor hole of the anchor (3), and the anchor hole is cleaned from the end of the anchor (3); 7. Insertion and tensioning of new steel strands: 7.1 Insertion of new steel strand Place the new steel strand on the left reel, lead the end out and pass it through the left conveying and threading machine, connect the new steel strand with the temporary steel strand end to end through the left beam surface operation window, pull the temporary steel strand in the opposite direction from the right, and convey the new steel strand to the right along with the temporary steel strand, and introduce it from the left beam surface operation window in turn, along the path of the old steel strand until the right beam surface operation window, at this time, confirm that the anti-slip anchor sleeve (16) on the new steel strand also reaches the end face of the wire distribution tube saddle (18), so that the new steel strand is inserted and the new steel strand is separated from the temporary steel strand (25); 7.2 New steel strand inserted into anchor At the beam surface operation window, the two ends of the new steel strand are respectively connected to the guide rods (24) reserved in the embedded pipe (6), and under the guidance of the guide rods, the new steel strand is passed through the anchor hole of the old steel strand of the anchor (3); 7.3 New Steel Strand Tensioning Install new clips in the anchor holes at both ends of the new steel strand, tension the new steel strand to the designed cable force, and thus complete the replacement of one steel strand; 8. Repeat the above steps 4 to 7 until all the steel strands of the cable are replaced; 9. Component resetting and installation, anti-corrosion treatment: An anti-slip stopper is installed on the new stay cable strand bundle, and the anti-slip anchor cylinder (17), the tower end operation window, the beam surface operation window, and the beam end anchor end operation window are restored.

2. The replacement construction method of the cable-stayed bridge with a low-tower cable-stayed bridge having an anti-slip anchoring device according to claim 1, Features: In step 2.1, a partitioning rod (28) is used to assist in disassembling the anti-slip block (15). The anti-slip block (15) is composed of a plurality of layers of layered plugboards (151). The partitioning rod (28) is inserted between the upper and lower rows of steel strands of the layered plugboards (151) at a position adjacent to the anti-slip block (15). The partitioning rod (28) separates the upper and lower rows of steel strands. The separation spacing p is greater than the thickness of the layered plugboards (151) to facilitate the removal of the layered plugboards (151). In this way, all the layered plugboards (151) are removed layer by layer, thereby achieving the removal of the anti-slip block (15) and allowing the steel strands to be pulled to the left without hindrance.

3. The replacement construction method of the cable-stayed bridge with a low-tower cable-stayed bridge having an anti-slip anchoring device according to claim 1, Features: In step 5.2, a lifting and pulling hook is arranged near the operating window on the beam surface, and a separation rod (28) is inserted into the layer where the old steel strand is located to leave a lifting space, and the old steel strand that has been released from the tension is lifted, and the end of the old steel strand is pulled out of the anchor until it is pulled out of the embedded pipe.

4. The replacement construction method of the cable-stayed bridge with a low-tower cable-stayed bridge having an anti-slip anchor device according to claim 1, Features: Step six, in the beam surface operation window, lift the introduced guide rod until the lower end of the guide rod is retracted into the anchor to expose the anchor cone hole, insert the anchor hole cleaning rod from the end of the anchor and use the cleaning cone head to clean the surface of the anchor cone hole.

5. The replacement construction method of the stay cable of the low tower cable-stayed bridge with an anti-slip anchoring device according to claim 1, characterized in that: Step Nine adopts the following operating steps: 9.1 Insert a separating drill into the space between the upper and lower adjacent rows of steel strands to separate the upper and lower adjacent rows of steel strands, and re-insert the layered insertion plate (151) of the anti-slip block. Separate layer by layer and reset the layered insertion plate (151) of each layer, so as to realize the reset of the anti-slip block; 9.2 Re-install the bearing nut (14) and the anti-slip anchoring cylinder (17); 9.3 Reset and install the tower-end cable hoop (13), lift the extension pipe (12), and reset and close the tower-end operation window; 9.4 Reset and install the beam-end cable hoop (8) and the beam-end shock absorber (7), lower the outer sleeve pipe (11) and the waterproof cover (9), and reset and close the beam-surface operation window; 9.5 Perform anti-corrosion treatment on the anchor and the end of the steel strand, reset the protective cover (5) component, and reset and close the beam-end anchoring-end operation window.

6. The replacement construction method of the stay cable of the low tower cable-stayed bridge with an anti-slip anchoring device according to any one of claims 1-5, characterized in that: The implementation order of the steps can be adjusted according to the actual situation or carried out simultaneously without affecting the achievement of the implementation purpose.

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