A method for erecting a large-span steel stranded cable road bridge in mountainous areas

Abstract

The invention provides a method for erecting a large-span steel strand cable road bridge in mountainous areas, which mainly comprises the following steps: installing a plurality of groups of steel strand load-bearing cables and two groups of steel strand stabilizing cables between anchors on left and right banks; assembling a stabilizing crossbeam on a right bank site, installing a lifting bracket above a steering cable saddle on the right bank, lifting the stabilizing crossbeam upward from directly below the steel strand load-bearing cables, making the two ends of the stabilizing crossbeam close to the two groups of steel strand stabilizing cables respectively, making the stabilizing crossbeam hang on the two groups of steel strand stabilizing cables through fixed pulleys at both ends, and evenly distributing the stabilizing crossbeam on the two groups of steel strand stabilizing cables; laying a bridge deck on the stabilizing crossbeam, connecting the stabilizing crossbeam and the bridge deck together, fixing the steel strand load-bearing cables between the bridge deck and the stabilizing crossbeam; installing curbwood on the bridge deck, installing guardrails at both ends of the bridge deck, and installing handrails and protective surface nets between every two guardrails.

Description

Technical Field

[0001] The invention belongs to the technical field of cableway bridge construction, and in particular relates to a method for erecting a large-span steel stranded cableway bridge in mountainous areas. Background Art

[0002] The terrain of the two ditches and three banks of Shuangbao Bridge is steep and "W" shaped. The valley is deep, the bottom elevation is 291.95m, the ground elevation is 510.72m, and the relative height difference is about 208.66m. The middle pier on Shuangbao Bridge is not connected to the main piers of large and small mileage, which causes inconvenience in transportation. If the three main piers are connected by independent access roads, it will not only lead to a large increase in the number of stations, a longer construction period, and a greatly increased access road length, but also lead to an increase in the land acquisition area, resulting in vegetation damage and increased soil erosion, and an increase in construction transportation distance, which will lead to increased waste gas emissions and driving safety risks in mountainous areas, and fail to achieve the goal of energy-saving, environmental protection, and economical and efficient engineering construction. Steel-stranded cable road bridges, with their simple structure, beautiful appearance, low cost and little impact on the surrounding environment, can meet the needs of quickly connecting the middle pier on the double-beam and the main pier with small mileage, forming a fast construction channel and solving the above problems. However, conventional steel-stranded cable load-bearing cable installations are difficult to construct, have low efficiency and high safety risks, which limits the use scenarios of steel-stranded cable road bridges. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a method for erecting a large-span steel stranded cable road bridge in mountainous areas, so as to overcome the above-mentioned problems or at least partially solve or alleviate the above-mentioned problems.

[0004] The present invention provides a method for erecting a large-span steel stranded cable road bridge in mountainous areas, comprising the following steps:

[0005] S001: Drill holes in the mountains on both sides of the bridge site, install anchor cables and inject grout, and build anchors and steering saddles at the anchor cables on both sides;

[0006] S002: Establishing a reciprocating traction system between the anchors on the left and right banks;

[0007] S003: installing multiple sets of steel strand load-bearing cables and two sets of steel strand stabilizing cables between the anchors on the left and right banks through a reciprocating traction system, wherein the two sets of steel strand stabilizing cables are distributed on both sides of the multiple sets of steel strand load-bearing cables;

[0008] S004: Assemble the stabilizing beam at the right bank site, install a lifting bracket above the steering cable saddle on the right bank, lift the stabilizing beam upward from directly below the steel strand load-bearing cable, so that the two ends of the stabilizing beam are close to the two groups of steel strand stabilizing cables respectively, install fixed pulleys at the two ends of the stabilizing beam, so that the stabilizing beam is suspended on the two groups of steel strand stabilizing cables through the fixed pulleys at the two ends, and after all the stabilizing beams are suspended, use steel cables to connect the two ends of all the stabilizing beams in series according to the preset stabilizing beam spacing, and use span-by-span clamping to connect the leftmost and rightmost stabilizing beams to the anchors on the left bank and the right bank respectively with steel cables, so that the stabilizing beams are evenly distributed along the steel strand stabilizing cables;

[0009] S005: firstly laying a bridge deck on the stabilizing crossbeam, then placing a crossbeam lifting device on the bridge deck, lifting the stabilizing crossbeam below by the crossbeam lifting device, so that the upper part of the stabilizing crossbeam is close to the steel strand load-bearing cable, connecting the stabilizing crossbeam and the bridge deck together, so that the steel strand load-bearing cable is fixed between the bridge deck and the stabilizing crossbeam;

[0010] S006: Install curb wood on the bridge deck, install guardrails at both ends of the bridge deck respectively, and install handrails and protective surface nets between every two guardrails.

[0011] In step S001, steel cable buckles are pre-buried on the front facades of the anchors on both sides, and the anchor cables are tested to ensure that the construction quality of the anchor cables meets the requirements.

[0012] In step S002, a traction winch is respectively set at the center line position on each of the anchors, and a large-load drone is used to start from the traction winch on the right bank, first to pull the guide rope across the river gorge, and then to pass the guide rope around the traction disc of the traction winch on the left bank and return to the starting point, and then install the traction device, so that the traction winches on both sides and the guide rope together form a guide traction system.

[0013] In step S002, the leading traction system is used to pull a traction rope thicker than the leading rope from the right bank to the left bank and then back, and the leading rope is replaced by the traction rope, and then the tractor is installed.

[0014] In step S003, the steel strand load-bearing cable and the steel strand stabilizing cable are prepared according to the length required by the design drawings, and the preset length position is marked, and the cable drums of the steel strand load-bearing cable and the steel strand stabilizing cable are installed behind the anchor on the right bank, and the steel strand load-bearing cable and the steel strand stabilizing cable are successively passed through the anchor plate and the anchor cable hole on the anchor on the right bank and then installed on the tractor, and the traction winch is driven to pull the steel strand load-bearing cable and the steel strand stabilizing cable into the anchor cable hole of the anchor on the left bank, and the marked positions on the steel strand load-bearing cable and the steel strand stabilizing cable are installed and fixed on the left bank. The traction winch is driven to pull the steel strand load-bearing cable and the steel strand stabilizing cable to the right bank to eliminate their free sag. After the traction is completed, the steel strand load-bearing cable and the steel strand stabilizing cable are placed in the notch of the steering saddle, and finally the loss of the steel strand load-bearing cable and the steel strand stabilizing cable is roughly and finely adjusted.

[0015] In step S004, after all the stabilizing beams are hung, the two ends of all the stabilizing beams are connected in series through steel cables according to the designed beam spacing, and the spans are clamped. The stabilizing beam on the rightmost bank is fixed to the anchor on the right bank by steel cables, and the first stabilizing beam on the leftmost side is connected to the reciprocating traction system in an isosceles triangle through two control cables to drive the traction winch to pull to the left bank. When the stabilizing beam is unfolded and in place, the steel cable is fixed to the anchor on the left bank. The stabilizing beam is initially installed. At this time, the steel strand stabilizing cable is under stress, and the middle part of the stabilizing beam is separated from the steel strand load-bearing cable.

[0016] In step S005, the position of the stabilizing beam is fine-tuned during the installation of the bridge deck to avoid excessive gaps in the bridge deck.

[0017] The method also includes S007: using a steel protective casing to protect the steel strand load-bearing cable between the steering saddle and the anchor, backfilling the gap between the steering saddle and the anchor with crushed stone, pouring a cement concrete slab on the top surface thereof, and backfilling the gap behind the anchors on the left and right banks with crushed stone.

[0018] The method for erecting a large-span steel strand cable railway bridge in mountainous areas of the present invention mainly comprises the following steps: after installing multiple groups of steel strand load-bearing cables and two groups of steel strand stabilizing cables between the anchors on the left and right banks, all stabilizing beams are suspended on the two groups of steel strand stabilizing cables through fixed pulleys at both ends, all stabilizing beams are evenly separated along the steel strand stabilizing cables, and bridge decks are laid on the stabilizing beams and multiple groups of steel strand load-bearing cables, and finally the bridge decks are connected with the stabilizing beams and the steel strand load-bearing cables. The method effectively solves the problem of difficulty in erecting steel strand cable railway bridges under the conditions of deep gullies and canyons in mountainous areas, and the construction is safe and efficient, simple and convenient, and the quality is controllable. The method has broad application prospects and can be applied in the implementation of similar engineering projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the completed construction of the anchorage and the steering cable saddle of the steel stranded cable road bridge of the present invention;

[0020] Figure 2 This is a schematic diagram of the construction of the pilot cable crossing the river ditch canyon of the present invention;

[0021] Figure 3 It is a schematic diagram of the formation of the pilot traction system of the present invention;

[0022] Figure 4 It is a schematic diagram of the construction of the pilot traction system of the present invention towing the traction rope across the river ditch canyon;

[0023] Figure 5 It is a schematic diagram of the completion of the reciprocating traction system of the present invention;

[0024] Figure 6 It is a schematic diagram of the construction of the traction steel strand load-bearing cable crossing the river ditch canyon of the present invention;

[0025] Figure 7 It is a schematic diagram of adjusting the load-bearing cable vector of the steel strand according to the present invention;

[0026] Figure 8 It is a schematic diagram of the steel strand load-bearing cable erected in the present invention;

[0027] Fig. 9 It is a schematic diagram of the lifting and stabilizing beam;

[0028] Fig.10 It is a schematic diagram of the traction of the stable beam;

[0029] Fig.11 This is a schematic diagram of the bridge deck installation;

[0030] Fig.12 It is a schematic diagram of the lifting of the stable beam when installing the beam bridge deck;

[0031] Fig.13 This is a schematic diagram of the bridge deck installation;

[0032] Fig.14 This is a schematic diagram of the bridge deck and guardrail after installation.

[0033] In the above figure: 1-anchor; 2-steering saddle; 3-anchor cable; 4-traction winch; 5-large load UAV; 6-lead rope; 7-lead traction system; 8-traction rope; 9-traction device; 10-reciprocating traction system; 11-steel strand load-bearing rope, 12-steel strand stabilizing rope; 13-marker; 14-stabilizing beam; 15-lifting bracket; 16-steel cable; 17-control cable; 18-bridge deck; 19-beam lifting device, 20-guardrail; 21-steel protective casing; 22-cement concrete slab.

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0035] Example 1

[0036] The present invention provides a method for erecting a large-span steel stranded cable road bridge in a mountainous area, comprising the following steps:

[0037] S001: drilling holes in the mountains on the left and right banks of the bridge site, installing anchor cables 3 and grouting, and constructing anchors 1 and steering saddles 2 at the anchor cables 3 on the left and right banks;

[0038] S002: Establishing a reciprocating traction system 10 between the anchors 1 on the left and right banks;

[0039] S003: installing multiple groups of steel strand load-bearing cables 11 and two groups of steel strand stabilizing cables 12 between the anchors 1 on the left and right banks through the reciprocating traction system 10, wherein the two groups of steel strand stabilizing cables 12 are distributed on both sides of the multiple groups of steel strand load-bearing cables 11;

[0040] S004: Assemble the stabilizing beam 14 at the right bank site, install a lifting bracket 15 above the steering saddle 2 on the right bank, lift the stabilizing beam 14 upward from directly below the steel strand load-bearing cable 11, so that the two ends of the stabilizing beam 14 are close to the two groups of steel strand stabilizing cables 12 respectively, install fixed pulleys at the two ends of the stabilizing beam 14, so that the stabilizing beam 14 is suspended on the two groups of steel strand stabilizing cables 12 through the fixed pulleys at the two ends, and after all the stabilizing beams 14 are suspended, use the steel cable 16 to connect the two ends of all the stabilizing beams 14 in series according to the preset spacing of the stabilizing beams 14, and clamp them in different spans, and connect the leftmost and rightmost stabilizing beams 14 to the anchors 1 on the left bank and the right bank respectively with the steel cable 16, so that the stabilizing beams 14 are evenly distributed along the steel strand stabilizing cables 12;

[0041] S005: First, lay the bridge deck 18 on the stabilizing crossbeam 14, then place the crossbeam lifting device 19 on the bridge deck 18, lift the stabilizing crossbeam 14 below by the crossbeam lifting device 19, make the upper part of the stabilizing crossbeam 14 close to the steel strand load-bearing cable 11, connect the stabilizing crossbeam 14 and the bridge deck 18 together, and fix the steel strand load-bearing cable 11 between the bridge deck 18 and the stabilizing crossbeam 14;

[0042] S006: Install curbwood on the bridge deck 18 , install guardrails 20 at both ends of the bridge deck 18 , and install handrails and protective surface nets between every two guardrails 20 .

[0043] Furthermore, in step S001, steel cable buckles are pre-buried on the front facades of the anchors 1 on both sides, and the anchor cables 3 are tested to ensure that the construction quality of the anchor cables 3 meets the requirements.

[0044] Further, in step S002, a traction winch 4 is respectively set at the center line position on each of the anchors 1, and a large-load drone 5 is used to start from the traction winch 4 on the right bank, first to pull the guide rope 6 across the river gorge, and then the guide rope 6 is passed around the traction disk of the traction winch 4 on the left bank and returned to the starting point, and then the traction device 9 is installed, so that the traction winches 4 on both sides and the guide rope 6 together form a guide traction system 7.

[0045] Further, in step S002, the leading traction system 7 is used to pull a traction rope 8 thicker than the leading rope 6 from the right bank to the left bank and then return, and the leading rope 6 is replaced by the traction rope 8, and then the tractor 9 is installed.

[0046] Further, in step S003, the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are prepared according to the length required by the design drawing, and the preset length position is marked 13, and the cable drums of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are installed behind the anchor 1 on the right bank, and the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are successively passed through the anchor plate and the anchor cable hole on the anchor 1 on the right bank and then installed on the tractor 9, and the traction winch 4 is driven to pull the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 To the anchor cable hole of the anchor 1 on the left bank, install anchors and clamps on the mark 13 on the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 on the left bank to fix them, drive the traction winch 4 to pull the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 to the right bank to eliminate their free sag, and after the traction is completed, place the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 in the groove of the steering saddle 2, and finally perform rough and fine adjustments on the loss of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12.

[0047] Further, in step S004, after all the stabilizing beams 14 are hung, the two ends of all the stabilizing beams 14 are connected in series by steel cables 16 according to the designed beam spacing, and the spans are clamped. The stabilizing beam 14 on the rightmost bank is fixed to the anchor 1 on the right bank by the steel cables 16, and the first stabilizing beam 14 on the leftmost side is connected to the reciprocating traction system 10 in an isosceles triangle through two control cables 17 to drive the traction winch 4 to pull to the left bank. When the stabilizing beam 14 is unfolded and in place, the steel cable 16 is fixed to the anchor 1 on the left bank, and the stabilizing beam 14 is initially installed. At this time, the steel strand stabilizing cable 12 is under stress, and the middle part of the stabilizing beam 14 is separated from the steel strand load-bearing cable 11.

[0048] Furthermore, in step S005, the position of the stabilizing beam 14 is fine-tuned during the installation of the bridge deck 18 to avoid excessive gaps in the bridge deck 18.

[0049] Furthermore, the method of the present invention also includes S007: using a steel protective sleeve 21 to protect the steel strand load-bearing cable 11 between the steering saddle 2 and the anchor 1, backfilling the gap between the steering saddle 2 and the anchor 1 with gravel, and pouring a cement concrete slab 22 on the top surface thereof, and backfilling the gap behind the anchor 1 on the left and right banks with gravel.

[0050] Example 2

[0051] The designed span of the steel stranded cable road bridge of Shuangbao Super-Large Bridge is 245.52m, the net width of the bridge deck is 3.8m, the height difference between the two banks is 3m, the horizontal distance from the center of the turning cable saddle on both banks to the front end face of the anchor is 8.5m, and the maximum heavy-load vehicle load is 60t. Under the conditions of constant load and 60t vehicle load (acting at the mid-span position), the mid-span verticality is 6.3m, and the maximum working wind design wind speed is level 6, which meets the material communication needs of the middle pier and the small mileage side of Shuangbao Super-Large Bridge.

[0052] The present invention will be further described in detail below in conjunction with the accompanying drawings, embodiments and engineering projects.

[0053] Step S001: drilling holes in the mountains on the left and right banks of the bridge site, installing anchor cables 3 and injecting grout, and constructing anchors 1 and steering saddles 2 at the anchor cables 3 on the left and right banks.

[0054] Steel cable buckles are pre-buried on the front facades of the anchors 1 on both sides, and the anchor cables 3 are tested to ensure that the construction quality of the anchor cables 3 meets the requirements.

[0055] refer to Figure 1 , carry out geological exploration at the bridge site, determine the structural form and parameters of anchor cable 3, drill holes in the mountain, install anchor cable 3 and inject grout, complete the construction of steel strand road bridge anchor 1 and steering saddle 2 on the left and right banks, and pre-embed steel cable buckles on the front facades of anchor 1 on both sides. Before the next step of work is carried out, it is necessary to test pull the anchor cable 3 to verify the construction quality of the anchor cable 3.

[0056] Taking the steel stranded cable road bridge of Shuangbao Super Bridge as an example, there are three rows of 23 strands of anchor cable 3 on one side, including nine strands in the first row, seven strands in the second row (including two spare strands), and nine strands in the third row. The free section of anchor cable 3 passes through breccia and weak rock layers, and the anchoring section enters the limestone or dolomite with complete structure. The free section of anchor cable 3 is >7.5m, the length of anchoring section is >15m, and the horizontal inclination angles from top to bottom are 5°, 9°, and 13° respectively. Anchor cable 3 adopts 12-Φ15.24 high-strength low-relaxation steel strand, the standard strength of steel strand is not less than 1860MPa, and the anchoring end adopts YJM15-12OVM anchor. In the rock anchor hole, the steel strand is fixed and positioned at intervals by expansion pieces and fasteners to increase the anchoring strength of the steel strand in the anchor hole. Before the construction of anchor cable 3, a pull-out test of the test cable must be carried out, with a pull-out force of 200t. The three rows of anchor cables 3 are tensioned in stages according to the progress of the cableway bridge, tensioned according to the tension control force of 100t, locked at 100t,

[0057] The anchorage 1 of the steel stranded cableway bridge adopts C30 reinforced concrete foundation beam, and the foundation beam size is: 13.4m (transverse bridge direction) × 3m (longitudinal bridge direction) × 3.7m (height). The left and right sections of anchorage 1 each use 60 HRB400 grade Φ25 steel bars, and the net protective layer thickness of the steel bars is 56mm. The stirrups of anchorage 1 use HPB300 grade Φ16 steel bars, and the net protective layer thickness of the steel bars is 40mm.

[0058] Step S002: Establish a reciprocating traction system 10 between the anchors 1 on the left and right banks.

[0059] refer to Figure 2 , Figure 3 , Figure 4 , Figure 5 In step S002, a traction winch 4 is set at the center line position of the steel strand track bridge on the anchor 1, and a large-load drone 5 is used to start from the traction winch 4 on the right bank, first to pull the guide rope 6 across the river ditch, and then pass the guide rope 6 around the traction disk of the traction winch 4 on the left bank, and return to the starting point, so that the traction winches 4 on both sides and the guide rope 6 together form a guide traction system 7.

[0060] In step S002, the leading traction system 7 is used to pull the traction rope 8 from the right bank to the left bank and then return, replacing the leading rope 6 to form a new reciprocating traction system 10. This step is repeated continuously, the smaller traction rope is replaced by the larger traction rope, and the traction device 9 is installed to form the final reciprocating traction system 10.

[0061] At the centerline of the steel strand bridge on anchor 1, a 10t traction winch 4 is used to traction the large-load drone 5 from the small mileage side. Nylon rope, then reciprocating cycle replaced with Nylon rope, with Nylon rope as traction rope replaced by Steel wire rope, using The steel wire rope is used as a traction rope 8 to pull the load-bearing rope to form a circulating traction system.

[0062] Step S003: installing multiple sets of steel strand load-bearing cables 11 and two sets of steel strand stabilizing cables 12 between the anchors 1 on the left and right banks through the reciprocating traction system 10 , wherein the two sets of steel strand stabilizing cables 12 are distributed on both sides of the multiple sets of steel strand load-bearing cables 11 .

[0063] refer to Figure 6 , Figure 7 , Figure 8 In step S003, the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are prepared according to the length required by the design drawing, and the preset length position is marked 13, and the cable drums of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are installed behind the anchor 1 on the right bank, and the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are successively passed through the anchor plate and the anchor cable hole on the anchor 1 on the right bank and then installed on the tractor 9, and the traction winch 4 is driven to pull the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 to the left bank. In the anchor cable hole of the anchor 1 on the bank, anchors and clamps are installed on the mark 13 on the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 on the left bank to fix them, and the traction winch 4 is driven to pull the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 to the right bank to eliminate their free sag. After the traction is completed, the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 are placed in the groove of the steering cable saddle 2, and finally the loss of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 is roughly and finely adjusted.

[0064] The method for roughly adjusting the angle of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 is as follows: after the right bank mark 13 passes over the anchor plate, the anchor and the clamp are installed, and the position of the right bank mark 13 is controlled to achieve the purpose of controlling the length of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12, thereby achieving the rough adjustment of the angle of the strand load-bearing cable 11, and the rough adjustment of all the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 is completed by this reciprocating process. The method for finely adjusting the angle of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 is as follows: after the rough adjustment of all the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 is completed, the angle of the steel strand load-bearing cable 11 is accurately adjusted by tensioning means until the line shape meets the design requirements. After the adjustment of all the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 is completed, the clip anti-loosening baffle is installed. At this point, the installation of the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 is completed.

[0065] The steel stranded cable road bridge of Shuangbao Super Bridge adopts high-strength, low-relaxation, non-bonded prestressed steel strands with a strength grade of 1860MPa. The load-bearing cables are 21 strands. Steel strands, stabilizing cables are two groups of six bundles, a total of twelve bundles Steel strands: Use the overall bundling and threading method, and use No. 12 iron wire to bundle five prestressed steel strands in a group every 5m, and pay attention to avoid entanglement during the bundling process.

[0066] The anchor point marks 13 need to be made in advance at both ends of the steel strands. The position of the mark 13 needs to fully consider the working length, the elongation of the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 when they are freely hanging, the elongation of the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 in the bridge state, and other factors that may affect the vector of the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12. The mark 13 must be clear and accurate.

[0067] Peel off the 70cm long PE protective film at one end, install a traction clamp 4m away from the end, use the reciprocating traction system 10 to pass the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 through the anchor plate and anchor cable hole on the small mileage side anchor 1 in turn, and then install them on the traction device 9, drive the traction winch 4 to pull the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 into the anchor cable hole of the large mileage side anchor 1, install the anchor at the large mileage side mark 13, and then fix it with a clamp. At the appropriate position of the load-bearing cable on the small mileage side, install the traction device 9 about 4m away from the anchor end, and use the reciprocating traction system 10 to tension it. After the mark 13 passes the anchor plate, install the anchor and fix it with the clamp. Control the position of the mark 13 on the small mileage side to achieve the purpose of controlling the linear shape of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12. After all the rough adjustments are completed, use the measuring instrument to measure and adjust the steel strand load-bearing cable 11 accurately through tensioning. The allowable error and the design position deviation are required to be within ±10mm. The installation order of the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12 is: left steel strand stabilizing cable 12 → left 1~5 bundles of steel strand load-bearing cables 11 → right 17~21 bundles of steel strand load-bearing cables 11 → middle 10~12 bundles of steel strand load-bearing cables 11 → left 6~9 bundles of steel strand load-bearing cables 11 → right 13~16 bundles of steel strand load-bearing cables 11 → right steel strand stabilizing cable 12. After all the steel strand load-bearing cables 11 and the steel strand stabilizing cables 12 are adjusted, the clip anti-loosening baffle is installed.

[0068] Step S004: assemble the stabilizing beam 14 at the right bank site, install a lifting bracket 15 above the steering saddle 2 on the right bank, lift the stabilizing beam 14 upward from directly below the steel strand load-bearing cable 11, so that the two ends of the stabilizing beam 14 are respectively close to the two groups of steel strand stabilizing cables 12, install fixed pulleys at both ends of the stabilizing beam 14, so that the stabilizing beam 14 is suspended on the two groups of steel strand stabilizing cables 12 through the fixed pulleys at both ends, after all the stabilizing beams 14 are hung, use steel cables 16 to connect the two ends of all the stabilizing beams 14 in series according to the preset spacing of the stabilizing beams 14, and connect them in spans, and connect the leftmost and rightmost stabilizing beams 14 to the anchors 1 on the left and right banks respectively with steel cables 16, so that the stabilizing beams 14 are evenly distributed along the steel strand stabilizing cables 12.

[0069] refer to Fig. 9 , Fig.10 In step S004, the stable beams 14 are assembled and placed in the right bank site according to classification and number. A lifting bracket 15 is installed above the steering saddle 2, and the stable beam 14 is lifted upward from directly below the steel strand load-bearing cable 11, so that the pulley groove at the end of the stable beam 14 is aligned with the steel strand stable cable 12, and the steel strand stable cable 12 is manually placed into the stable pulley base on the beam, and the roller and pin are installed to hang the stable beam 14 on the steel strand stable cable 12, and its connecting parts are coated with sufficient anti-corrosion oil. After all the stable beams 14 are hung, the steel cables 16 are used to connect the end arms of all the stable beams 14 in series according to the designed beam spacing, and the spans are clamped. The rightmost bank stable beam 14 is fixed to the pre-buried buckle of the right bank anchor 1 with the steel cables 16 to ensure the accurate position of the rightmost bank stable beam 14. The first stable beam 14 on the leftmost bank and the reciprocating traction system 10 are connected in an isosceles triangle by two control cables 17, and the traction winch 4 is driven to pull to the left bank. After the stable beam 14 is deployed and in place, the steel cable 16 is fixed to the pre-buried buckle of the left bank anchor 1. The stable beam 14 is initially installed. At this time, the steel strand stable cable 12 is stressed, and the middle part of the stable beam 14 is separated from the steel strand load-bearing cable 11. Note that the stable beam 14 matches the number of bridge panels 18 within its span. After the stable beam 14 is initially positioned, it is still necessary to fine-tune the position of the stable beam 14 during the installation of the bridge panel 18 to prevent the gap between the bridge panel 18 from being too large.

[0070] A beam assembly site is leveled below the steel strand load-bearing cable 11 at the front of the turning cable saddle 2 of the cableway bridge, and the components of the stable beam 14 of the whole bridge are placed on the assembly site respectively. After being assembled and connected into a whole beam, they are classified and numbered and placed. The stable beam 14 is welded into an I-shaped steel beam using low-alloy high-strength steel Q420 steel plate, and the designed beam spacing is 8.22m, which matches the bridge deck 18 in the interval of the adjacent stable beam 14. A lifting bracket 15 is installed above the turning cable saddle 2, and the stable beam 14 is lifted upward from directly below the steel strand load-bearing cable 11, so that the pulley groove at the end of the beam end boom is aligned with the steel strand stable cable 12, and the steel strand stable cable 12 is manually placed in the stable pulley base on the stable beam 14, and the roller and pin are installed, so that the stable beam 14 is suspended on the steel strand stable cable 12, and its connecting parts are coated with sufficient anti-corrosion oil. The stable beam 14 of the whole bridge is suspended on the steel strand stable cable 12 in the above manner. After all the stabilizing beams 14 are hung, the two suspension arms of the stabilizing beams 14 are connected in series using small steel cables 16 according to the designed beam spacing, and the two spans are connected. Then, the first beam on the outermost side and the reciprocating traction system 10 are connected in an isosceles triangle through two control cables 17, and the winch is started to pull toward the long mileage side and unfold it into place.

[0071] Step S005, first lay the bridge deck 18 on the stabilizing beam 14, then place the beam lifting device 19 on the bridge deck 18, lift the stabilizing beam 14 below by the beam lifting device 19, make the upper part of the stabilizing beam 14 close to the steel strand load-bearing cable 11, connect the stabilizing beam 14 and the bridge deck 18 together, and fix the steel strand load-bearing cable 11 between the bridge deck 18 and the stabilizing beam 14.

[0072] In step S005 , the position of the stabilizing beam 14 is fine-tuned during the installation of the bridge deck 18 to avoid excessive gaps in the bridge deck 18 .

[0073] refer to Fig.11 , Fig.12 , Fig.13 , Fig.14 The bridge deck 18 between the two stabilizing beams 14 is a group and is transported by a special trolley. The bridge deck 18 is laid from the right bank to the left bank. When the bridge deck 18 is installed on the stabilizing beam 14, since the stabilizing beam 14 is separated from the steel strand load-bearing cable 11, it is necessary to place a bridge deck 18 in advance about 60 cm in front of the stabilizing beam 14, and place the beam lifting device 19 on the bridge deck 18 near the bridge deck 18. The hook of the beam lifting device 19 is used to pull the stabilizing beam 14 close to the steel strand load-bearing cable 11, and the bridge deck 18, the stabilizing beam 14, and the steel strand load-bearing cable 11 are bolted and fixed with bolts passing through the reserved holes.

[0074] In S006 , a curb is installed on the bridge deck 18 , guardrails 20 are installed at both ends of the bridge deck 18 , and a handrail rope and a protective surface net are installed between every two guardrails 20 .

[0075] Use U-shaped clips and pressure plates to connect the bridge deck 18 and the steel strand load-bearing cable 11 into a whole. Use U-shaped clips to pass through the reserved holes to bolt and fix the guardrail 20 column base, curb wood and steel strand load-bearing cable 11, and finally install the remaining handrail ropes. Review the bridge deck line shape. If fine-tuning is required, it can be achieved by appropriately and synchronously tensioning the steel strand load-bearing cable 11 and the steel strand stabilizing cable 12. After the entire line shape meets the requirements, install the guardrail 20 and the protective surface net.

[0076] Step S007: Use a steel protective casing 21 to protect the steel strand load-bearing cable 11 between the steering saddle 2 and the anchor 1, backfill the gap between the steering saddle 2 and the anchor 1 with gravel, and cast a cement concrete slab 22 on the top surface, and backfill the gap behind the anchor 1 on the left and right banks with gravel to connect with the existing access road.

[0077] Before the deck 18 of the steel strand track bridge of Shuangbao Super Bridge is laid, one strand is pulled on each side of the steel strand track bridge. Handrail wire rope. During the bridge deck paving operation, workers buckle their safety belts to the handrail rope and use it as a safety rope for high-altitude operations.

[0078] The bridge deck 18 is formed by die-pressing and welding 3mm low-alloy high-strength steel Q420 plate, of which: the bridge deck 18 connecting the crossbeam is 230mm wide and 165mm thick, and the other bridge decks 18 are 420mm wide and 130mm thick, and are laid in order from small mileage to large mileage.

[0079] The hook of the beam lifting device 19 is used to pull the stable beam 14, and the bridge deck 18 and the stable beam 14 are bolted and fixed through the reserved holes with M20 bolts. The bridge deck 18 and the steel strand load-bearing cable 11 are connected as a whole through U-shaped clips and pressure plates. The base of the guardrail 20 column, the curb wood and the steel strand load-bearing cable 11 are bolted and fixed through the reserved holes on the bridge deck 18 with U-shaped clips. The curb wood is made of 15cm×20cm (height×width) Northeast pine. The guardrail 20 columns are arranged at a spacing of 2.1m, and the guardrail 20 protective surface net is made of Galvanized steel wire mesh, lap length 10cm. The steel strand load-bearing cable 11 between the steering saddle 2 and the anchor 1 is made of The bridge is protected by a 4mm thick steel protective casing 21. The gap between the steering saddle 2 and the anchor 1 is backfilled with well-graded crushed stone, and a 25cm C30 cement concrete slab 22 is poured on the top surface. The gap behind the anchors 1 on both sides is backfilled with well-graded crushed stone and connected to the existing access road. The construction of the entire bridge is completed.

[0080] Carry out acceptance inspection, including: appearance inspection, physical inspection, static load test and dynamic load test. The inspection items include: displacement, static deflection, static strain (stress), cracks, temperature, cable tension, structural line shape, verticality, structural size, bearing capacity, concrete strength, carbonization depth, etc.

[0081] The static load test is implemented as follows: water tank loading is used at the mid-span position. The water tank size is 4.2m×3.6m×1.4m×3, the load capacity is 60t, and it is carried out in 3 levels. The dynamic load test is implemented as follows: driving a three-axle truck with a maximum load of 60t on this steel strand cable track bridge, not exceeding the maximum driving speed and eccentric position, passing the steel strand cable track bridge. The test contents are: strain, deflection, cracks, load-bearing cable force, testing the maximum deflection in the mid-span, and the steel strand cable track bridge is completed after the acceptance inspection is qualified.

[0082] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. The components and structures not described in detail in this embodiment are well-known components and common structures or common means in the industry, and are not described here one by one.

Claims

1. A method for erecting a large-span steel stranded cable road bridge in mountainous areas, characterized in that: The following steps are involved: S001: drilling holes in the mountains on the left and right banks of the bridge site, installing anchor cables (3) and injecting grout, and constructing anchors (1) and steering saddles (2) at the anchor cables (3) on the left and right banks; S002: Establishing a reciprocating traction system (10) between the anchors (1) on the left and right banks; S003: installing a plurality of sets of steel strand load-bearing cables (11) and two sets of steel strand stabilizing cables (12) between the anchors (1) on the left and right banks by means of a reciprocating traction system (10), wherein the two sets of steel strand stabilizing cables (12) are distributed on both sides of the plurality of sets of steel strand load-bearing cables (11); S004: Assemble a stabilizing beam (14) at the right bank site, install a lifting bracket (15) above the steering saddle (2) on the right bank, lift the stabilizing beam (14) upward from directly below the steel strand load-bearing cable (11), so that both ends of the stabilizing beam (14) are close to the two sets of steel strand stabilizing cables (12), install fixed pulleys at both ends of the stabilizing beam (14), and suspend the stabilizing beam (14) on the two sets of steel strand stabilizing cables (12) through the fixed pulleys at both ends. After all the stabilizing beams (14) are hung on the steel strand stabilizing cables (12), the two ends of all the stabilizing beams (14) are connected in series using steel cables (16) according to a preset spacing between the stabilizing beams (14), and the two ends are connected in series by spans, and the leftmost and rightmost stabilizing beams (14) are connected to the anchors (1) on the left and right banks respectively by steel cables (16), so that the stabilizing beams (14) are evenly distributed along the steel strand stabilizing cables (12); S005: firstly laying a bridge deck (18) on the stabilizing crossbeam (14), then placing a crossbeam lifting device (19) on the bridge deck (18), lifting the stabilizing crossbeam (14) below by means of the crossbeam lifting device (19), so that the upper part of the stabilizing crossbeam (14) is close to the steel strand load-bearing cable (11), connecting the stabilizing crossbeam (14) and the bridge deck (18) together, so that the steel strand load-bearing cable (11) is fixed between the bridge deck (18) and the stabilizing crossbeam (14); S006: installing a curb on the bridge deck (18), installing guardrails (20) at both ends of the bridge deck (18), and installing a handrail rope and a protective surface net between every two guardrails (20).

2. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1 is characterized in that: In step S001, steel cable buckles are pre-buried on the front facades of the anchors (1) on both sides, and the anchor cables (3) are tested to ensure that the construction quality of the anchor cables (3) meets the requirements.

3. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1, characterized in that: In step S002, a traction winch (4) is respectively arranged at the center line position on each anchor (1), and a large-load drone (5) is used to start from the traction winch (4) on the right bank, first to pull the guide rope (6) across the river gorge, and then to pass the guide rope (6) around the traction disc of the traction winch (4) on the left bank and return to the starting point, and then install a tractor (9), so that the traction winches (4) on both banks and the guide rope (6) together form a guide traction system (7).

4. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 3 is characterized in that: In step S002, the leading traction system (7) is used to tow a traction rope (8) thicker than the leading rope (6) from the right bank to the left bank and then back, and the leading rope (6) is replaced by the traction rope (8), and then the tractor (9) is installed.

5. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1, characterized in that: In step S003, the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) are prepared according to the length required by the design drawing, and the preset length position is marked (13). The cable drums of the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) are installed behind the anchor (1) on the right bank. The steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) are successively passed through the anchor plate and the anchor cable hole on the anchor (1) on the right bank and then installed on the tractor (9). The traction winch (4) is driven to pull the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) to the right bank. Anchors and clamps are installed in the anchor cable holes of the anchor (1) on the left bank at the positions of the marks (13) on the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) on the left bank to fix them, and the traction winch (4) is driven to pull the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) toward the right bank to eliminate their free sag. After the traction is completed, the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) are placed in the grooves of the steering cable saddle (2), and finally the loss of the steel strand load-bearing cable (11) and the steel strand stabilizing cable (12) is roughly and finely adjusted.

6. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1, characterized in that: In step S004, the stabilizing beam (14) on the rightmost bank is fixed to the anchor (1) on the right bank by means of a steel cable (16), and the first stabilizing beam (14) on the leftmost side is connected to the reciprocating traction system (10) in the form of an isosceles triangle by means of two control cables (17), and the traction winch (4) is driven to be pulled toward the left bank. When the stabilizing beam (14) is deployed and in place, the steel cable (16) is fixed to the anchor (1) on the left bank, and the preliminary installation of the stabilizing beam (14) is completed. At this time, the steel strand stabilizing cable (12) is stressed, and the middle part of the stabilizing beam (14) is in a separated state from the steel strand load-bearing cable (11).

7. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1, characterized in that: In step S005, the position of the stabilizing beam (14) is fine-tuned during the installation of the bridge deck (18) to avoid excessive gaps in the bridge deck (18).

8. The method for erecting a large-span steel stranded cableway bridge in mountainous areas according to claim 1, characterized in that: The method further comprises S007: using a steel protective sleeve (21) to protect the steel strand load-bearing cable (11) between the steering cable saddle (2) and the anchor (1), backfilling the space between the steering cable saddle (2) and the anchor (1) with crushed stone, pouring a cement concrete slab (22) on the top surface thereof, and backfilling the space behind the anchor (1) on the left and right banks with crushed stone.

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