A modification method for a steel box girder cantilever crane based on a cantilever pouring bridge construction machine

Abstract

The present invention discloses a modification method for a cantilever crane of a steel box girder based on a cantilever grouting bridge-building machine, which belongs to the technical field of bridge construction, and includes a main beam, wherein the main beam is connected with an upper cross beam and a middle cross beam, a walking system is arranged below the main beam, a lifting mechanism is arranged above the main beam, and a rear anchor system for increasing stability is arranged behind the main beam; the lifting mechanism is connected with a hoisting device for hoisting the steel box girder, and the hoisting device is located in front of the main beam. The modification method is carried out by removing the template system of the original thousand-ton super-large bridge-building machine, retaining the main beam force system, upgrading the walking system, the anchoring system, and assembling the hoisting system. The equipment cost and time loss caused by the dismantling and withdrawal of the super-large bridge-building machine and the introduction of a new bridge crane are reduced, which ensures the construction period and saves huge costs.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a modification method of a steel box girder cantilever crane based on a cantilever pouring bridge-building machine. Background Art

[0002] With the acceleration of my country's high-speed railway construction, the railway system has been continuously improved in quality and speed, and the design level of railway lines has become higher and higher. In large-span river canyons, cable-stayed bridges and suspension bridges have become the first choice for design in order to take into account aesthetics. However, under high-level design conditions, the main body of the bridge is getting larger and larger, and construction technology, work safety and quality have become key issues in the production process. As the main body of the bridge, the design of the formwork system of the concrete main beam is the core. The cantilever pouring bridge-making machine used in the construction of the reinforced concrete main beam of the super-large cross-section cable-stayed bridge must take into account the characteristics of bearing capacity, safety quality and convenient operation.

[0003] After the construction of the reinforced concrete beam end of the cable-stayed bridge is completed, the next step will be the hoisting construction of the steel box girder. In the prior art, the bridge-building machine is usually dismantled and withdrawn, and then a crane is introduced to carry out the hoisting construction of the steel box girder. The above method involves huge waste of time and labor due to the dismantling of the hanging basket and the introduction of another bridge crane. Therefore, this scheme proposes a modification method of the steel box girder cantilever crane based on the cantilever pouring bridge-building machine. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, a modification method of a steel box girder cantilever crane based on a cantilever cast-in-place bridge-building machine is provided.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] The present invention proposes a steel box girder cantilever crane based on a cantilever cast-in-place bridge-building machine, comprising a main beam, wherein the main beam is connected to an upper crossbeam and a middle crossbeam, a walking system is provided below the main beam, a lifting mechanism is provided above the main beam, and a rear anchor system for increasing stability is provided behind the main beam; a hoisting device for hoisting the steel box girder is connected below the lifting mechanism, and the hoisting device is located in front of the main beam.

[0007] Preferably, the hanging point adjustment mechanism includes a longitudinal sliding track positioned and installed at the front end above the main beam, and the longitudinal sliding track is detachably connected to a horizontally arranged cylinder; the upper cross beam is slidably connected to the main beam, and the cylinder is connected to the upper cross beam, and the cylinder can push the upper cross beam to move along the longitudinal sliding track.

[0008] Preferably, the lifting mechanism includes a steel strand winding rack positioned and installed at the rear end above the main beam, and the steel strand winding rack is located behind the longitudinal sliding track; the upper cross beam is connected to a pushing rear seat, and the pushing rear seat is connected to a vertically arranged lifting jack, and the lifting jack is used to drive the steel box beam segment to rise and fall; the pushing rear seat is also connected to a steel strand guide frame for guiding the steel strand.

[0009] Preferably, the rear anchor system comprises a lifting leg, one end of which is connected to the middle cross beam, and the other end is located on the top surface of the box beam, the box beam is slidably connected with a hanging leg, and a corbel is connected below the middle cross beam.

[0010] Preferably, the sling includes an adjustment sleeve connected to the steel strand, the adjustment sleeve is detachably connected to the sling main beam, the sling main beam can move in the adjustment sleeve; the sling main beam is connected to at least one shoulder pole beam, the shoulder pole beam can move along the main beam. There are two shoulder pole beams, which are respectively located at both ends of the sling main beam, and two hanging ears are welded on the top surface of the steel box beam, which are connected to the shoulder pole beam by a steel sling.

[0011] Preferably, the steel strand is connected to the adjustment sleeve via an anchor, and a jack for adjusting the center of gravity of the lifting point is also connected to the main beam of the lifting device, and the jack is connected to the anchor.

[0012] Preferably, the walking system includes a track beam located below the main beam, and the main beam can move along the track beam; and also includes a jack for driving the main beam to move.

[0013] A modification method of a steel box girder cantilever crane based on a cantilever pouring bridge-building machine, using the above-mentioned steel box girder cantilever crane based on a cantilever pouring bridge-building machine, comprises the following steps:

[0014] Step 1: After the beam concrete is poured and cured, tensioning and corresponding cable installation are carried out, and the cantilever pouring bridge-building machine is moved to the top of the beam concrete to complete the anchoring;

[0015] Step 2: Remove the topmost heightened and reinforced beam section of the main beam. Remove the slings and suspenders in the middle of the upper beam, and keep the side force-bearing rod system; lift the upper beam, and install a suspension point adjustment mechanism on the main beam to adjust the suspension point;

[0016] Step three: Make a corbel on the top of the hanging leg, disassemble the hanging leg and the middle beam, so that the corbel is located below the middle beam, and pre-embed and weld the running track on the flange plate, so that the hanging leg can move in the running track; after the upper beam is lifted, disassemble the lifting bracket beam and the legs, and connect and fix the remaining full-length middle beam to the main beam to form a stable whole; move the lifting legs to the inner side of the outermost main beam and both sides of the main beam in the middle, and install them below the main beam of the lifting bracket; at the same time, process the steel box girder section, remove the rear anchor as a whole and move it inward to the top plate of the box room, weld 2 hanging ears on the upper crossbeam in the middle of the lifting point, and connect the hanging ears to the shoulder beam with steel slings to transmit force. Each rear anchor point is equipped with 4 anchor rods, and the lifting ears of the steel box girder are used as anchor points, which are shared by both the anchor point and the lifting point;

[0017] Step 4: Install a lifting mechanism on the main beam to lift the steel box beam. At the same time, set up a hydraulic station on the beam surface between the main beams of the bridge-building machine to provide power for the lifting jack; install a hoist at the front end of the lifting mechanism to connect the hoist to the steel box beam, and then lift the steel box beam through the lifting mechanism to complete the installation of the steel box beam.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The present invention refits the original thousand-ton super-large bridge-building machine by removing the template system, retaining the main beam force system, upgrading the walking system, anchoring system, and assembling the lifting system. The machine has a strong load-bearing capacity and can achieve one-time lifting of the subsequent 12m long steel box girder in place, which is safe and reliable. It reduces the equipment costs and time losses caused by the removal of super-large bridge-building machines and the introduction of new bridge cranes, ensuring the construction period while saving huge costs. At the same time, the super-large bridge-building machine is modified in situ to a bridge crane, which is a pioneering technology, and will also provide experience for similar projects in the future.

[0020] 2. The present invention also separates the middle cross beam and the hanging legs, and connects a running track to the installed steel box beam flange plate to achieve sliding connection between the hanging legs and the running track, so that the bottom formwork and side formwork system can be moved separately after the corbels and the hanging legs are hoisted along the steel-concrete section steel box beam, thereby realizing the integrated construction of the bridge crane and the hanging basket, which is fast, efficient, economical, safe and reliable.

[0021] 3. The present invention also avoids the outer cable guide tube and the hanging leg running track by removing the entire rear anchor and moving it inward to the top plate of the box room. Two hanging ears are welded on the crossbeam above the center of the lifting point, and the steel lifting belt connects the hanging ears to the shoulder beam to transmit force. Four anchor rods are set at each rear anchor point, and the lifting ears of the steel box beam are used as anchor points, which are shared by the anchor point and the lifting point, reducing the design of separate anchor points. The lifting legs are moved inward, and the lifting points, lifting ears, etc. can be effectively avoided during the subsequent steel beam lifting process.

[0022] 4. The present invention also retains the full-length cross beam after removing the jacking bracket and the middle cross beam hanging legs, and connects the three main beams with anchor bolts to form a truss force, thereby ensuring that the upper part of the main beam is relatively flat, effectively ensuring the overall stability during the construction process, and ensuring the construction quality.

[0023] 5. The present invention also sets the hydraulic station on the beam surface between the main beams of the bridge-building machine, which is convenient for construction personnel to operate synchronously on the beam surface and is conducive to observing the lifting and approaching situation. At the same time, the lifting point beam can slide longitudinally along the main beam of the bridge-building machine to realize the longitudinal horizontal movement of the steel box beam; the synchronous lifting jack pulls the steel strand to realize the vertical lifting of the steel beam segment, and the steel strand has a strong force-bearing capacity. Through the jack, the upper beam lifting point realizes the lateral adjustment of the steel box beam, and the lateral fine-tuning of the steel box beam is more stable and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0025] Figure 1 It is an overall schematic diagram of the main beam in the present invention;

[0026] Figure 2 It is a schematic diagram of the spreader;

[0027] Figure 3 yes Figure 1 Schematic diagram of the AA suspension point adjustment mechanism;

[0028] Figure 4 yes Figure 1 Schematic diagram of the middle BB rear anchor system;

[0029] Figure 5 yes Figure 1 Schematic diagram of the lifting points of the CC steel box girder;

[0030] Figure 6 This is a schematic diagram of the original bridge-building machine;

[0031] Figure 7 This is the original bridge-building machine hanging leg diagram;

[0032] Figure 8 This is a schematic diagram of the original bridge-building machine's force-bearing rod system.

[0033] Description of reference numerals:

[0034] 1. Main beam; 2. Upper crossbeam; 3. Middle crossbeam; 4. Steel strand; 5. Steel strand guide frame; 6. Jack; 7. Steel strand reel; 8. Adjustment sleeve; 9. Track beam; 10. Hoisting equipment main beam; 11. Lifting lug; 13. Pushing rear seat; 14. Longitudinal sliding track; 15. Shoulder pole beam; 16. Cylinder; 17. Lifting legs; 18. Traveling track; 19. Hanging legs; 20. Corbel; 21. Sling; 22. Original hanging legs; 23. Lifting jack; 24. Rear anchor beam; 25. Hoisting equipment main beam positioning anchor bolt; 26. Lifting bracket beam. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. For the convenience of description, the direction to be constructed in this solution is the front, and the part to be constructed is the rear.

[0036] The cantilever bridge-building machine with a large cross-section put into use in the cable-stayed bridge of this project has reached the world's largest in terms of single body volume, weight and bearing capacity, and there is no mature research yet. After the construction of the reinforced concrete beam end of the cable-stayed bridge is completed, the steel box girder will be hoisted. In order to reduce the huge cost caused by the removal of the hanging basket and the entry of another bridge deck crane, and to make full use of equipment resources, the best solution is to convert the hanging basket into a steel box girder bridge deck crane. The modification method has become a key research issue. The bridge-building machine of this project is 19.715m long, and the height of a single main beam 1 exceeds 3.6m. The weight of a single-side bridge-building machine is 370t, and its own volume is large enough. In response to the problem of modified cranes, a variety of dismantling and assembly methods were studied in detail, and finally the modification method of removing the template system, retaining the main beam 1 force system, upgrading the walking system, anchoring system, and assembling the hoisting system was determined. This can minimize disassembly and assembly, speed up the construction progress, and meet the crane load requirements when hoisting the steel box girder.

[0037] like Figure 1-8 A steel box girder cantilever crane based on a cantilever cast-in-place bridge-building machine is shown, comprising a main beam 1, the main beam 1 being connected to an upper cross beam 2 and a middle cross beam 3, a walking system being provided below the main beam 1, a lifting mechanism being provided above the main beam 1, and a rear anchor system being provided behind the main beam 1 for increasing stability; a hoisting device for hoisting the steel box girder is connected below the lifting mechanism, and the hoisting device is located in front of the main beam 1.

[0038] The lifting point adjustment mechanism includes a longitudinal sliding track 14 positioned and installed at the front end above the main beam 1. The longitudinal sliding track 14 is detachably connected to a horizontally arranged cylinder 16. The above-mentioned detachable connection is an anchor connection. The cylinder 16 can adjust the position along the anchor hole on the longitudinal sliding track 14 to ensure use; a sliding shoe is provided at the bottom of the upper beam 2, and the upper beam 2 is slidably connected on the main beam 1. The cylinder 16 is connected to the upper beam 2, and the cylinder 16 can push the upper beam 2 to move along the longitudinal sliding track 14.

[0039] The sling includes an adjustment sleeve 8 connected to the steel strand 4. The adjustment sleeve 8 is detachably connected to the sling main beam 10, and the sling main beam 10 can move in the adjustment sleeve 8; the sling main beam 10 is connected to at least one shoulder beam 15, and the shoulder beam 15 can move along the main beam 1. There are two shoulder beams 15, which are respectively located at both ends of the sling main beam 10. Two hanging ears are welded on the top surface of the steel box beam, and the hanging ears are connected to the shoulder beam 15 through a steel sling. The steel strand is connected to the adjustment sleeve 8 through an anchor. The sling main beam 10 is also connected to a jack for adjusting the center of gravity of the lifting point, and the jack is connected to the anchor.

[0040] The lifting mechanism includes a steel strand winding rack 7 positioned and installed at the rear end above the main beam 1. The steel strand winding rack 7 is used to wind up the steel strand 4 to prevent affecting the lifting of the steel box beam and ensure normal construction. The steel strand 4 winding rack is located behind the longitudinal sliding track 14; the upper cross beam 2 is connected to a push rear seat 13, and the push rear seat 13 is connected to a vertically arranged lifting jack 23. The lifting jack 23 is used to drive the steel box beam segment to perform vertical lifting; the push rear seat 13 is also connected to a steel strand guide frame 5 for guiding the steel strand 4.

[0041] The traveling system includes a track beam 9 located below the main beam 1 , along which the main beam 1 can move; and also includes a jack 6 for driving the main beam 1 to move.

[0042] A modification method of a steel box girder cantilever crane based on a cantilever pouring bridge-building machine, using the above-mentioned steel box girder cantilever crane based on a cantilever pouring bridge-building machine, comprises the following steps:

[0043] Step 1: After the beam concrete is poured and cured, tensioning and corresponding cable installation are carried out, and the cantilever pouring bridge-building machine is moved to the top of the beam concrete to complete the anchoring;

[0044] Step 2: Remove the uppermost heightened and reinforced beam section of the main beam 1. Remove the sling 21 and the sling rod in the middle of the upper crossbeam 2, and keep the side force-bearing rod system; lift the upper crossbeam 2, and install a sling point adjustment mechanism on the main beam 1 to adjust the sling point;

[0045] After removing the lifting bracket and the hanging legs 19 of the middle cross beam 3, the full-length cross beam is retained and connected with the anchor bolts between the three main beams 1 to form a truss force, which ensures that the upper part of the main beam 1 is relatively flat, effectively ensuring the overall stability during the construction process and ensuring the construction quality. In addition, by separating the middle cross beam 3 and the hanging legs 19, and connecting the running track 18 to the installed steel box beam flange plate, the hanging legs 19 are slidably connected with the running track 18, so that the bottom formwork and side formwork system of the bracket 20 and the hanging legs 19 can be moved separately after the steel box beam of the steel-concrete section is hoisted, and the integrated construction of the crane and the hanging basket is realized, which is fast, good, economical, safe and reliable.

[0046] Step three: Make a corbel 20 on the top of the hanging leg 19, disassemble the hanging leg 19 and the middle beam 3 so that the corbel 20 is located below the middle beam 3, and pre-embed and weld the running track 18 on the flange plate, so that the hanging leg 19 can move in the running track 18; after the upper beam 2 is lifted, disassemble the lifting bracket crossbeam 26 and the support leg, and connect and fix the remaining full-length middle beam 3 to the main beam 1 to form a stable whole; move the lifting support leg 17 to the inner side of the outermost main beam 1 and the two sides of the main beam 1 in the middle position, and install it below the main beam of the lifting bracket; at the same time, process the steel box girder section, remove the rear anchor as a whole and move it inward to the top plate of the box room, weld two hanging ears on the crossbeam in the middle of the lifting point, and connect the hanging ears to the shoulder beam 15 with the steel sling to transmit force. Four anchor rods are set at each rear anchor point, and the lifting ear 11 of the steel box girder is used as the anchor point, which is shared by the anchor point and the lifting point;

[0047] By removing the entire rear anchor and moving it inward to the top plate of the box room, the outer cable guide and the hanging leg 19 running track 18 are avoided. Two hanging ears are welded on the crossbeam above the center of the lifting point, and the steel lifting belt connects the hanging ears to the shoulder beam 15 to transmit force. Four anchor rods are set at each rear anchor point, and the lifting ear 11 of the steel box beam is used as the anchor point, which is shared by the anchor point and the lifting point, reducing the design of separate anchor points. The lifting leg 17 is moved inward, and the lifting point, the lifting ear 11, etc. can be effectively avoided during the subsequent steel beam lifting process, thereby improving construction efficiency.

[0048] Step 4: Install a lifting mechanism on the main beam 1 to realize the lifting of the steel box girder. At the same time, set a hydraulic station on the beam surface of the bridge-building machine main beam 1 to provide power for the lifting jack 23 and the jack 6; install a sling at the front end of the lifting mechanism to connect the sling to the steel box girder, and then lift the steel box girder through the lifting mechanism to complete the installation of the steel box girder.

[0049] By removing the template system of the original 1,000-ton super-large bridge-building machine, retaining the main beam 1 force system, upgrading the walking system, anchoring system, and assembling the lifting system, the load-bearing capacity is strong, and the subsequent 12m long steel box girder can be lifted in place at one time, which is safe and reliable. It reduces the equipment cost and time loss caused by the removal of the super-large bridge-building machine and the introduction of new bridge cranes, ensuring the construction period while saving huge costs. At the same time, the super-large bridge-building machine is modified in situ to the bridge deck crane, which is a pioneering technology, and will also provide experience for similar projects in the future.

[0050] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for modifying a steel box girder cantilever crane based on a cantilever grouting bridge-building machine, comprising a steel box girder cantilever crane based on a cantilever grouting bridge-building machine, wherein the steel box girder cantilever crane based on a cantilever grouting bridge-building machine comprises a main beam (1), wherein the main beam (1) is connected to an upper cross beam (2) and a middle cross beam (3), and wherein: A walking system is provided below the main beam (1), a lifting mechanism is provided above the main beam (1), and a rear anchor system for increasing stability is provided behind the main beam (1); the lifting mechanism is connected to a hoisting device for hoisting a steel box beam, and the hoisting device is located in front of the main beam (1); The suspension point adjustment mechanism comprises a longitudinal sliding track (14) positioned and installed at the front end above the main beam (1), wherein the longitudinal sliding track (14) is detachably connected to a horizontally arranged oil cylinder (16); the upper cross beam (2) is slidably connected to the main beam (1), and the oil cylinder (16) is connected to the upper cross beam (2), and the oil cylinder (16) can push the upper cross beam (2) to move along the longitudinal sliding track (14); The lifting mechanism comprises a steel strand winding frame (7) positioned and installed at the rear end above the main beam (1), and the steel strand winding frame (7) is located behind the longitudinal sliding track (14); the upper cross beam (2) is connected to a push rear seat (13), and the push rear seat (13) is connected to a vertically arranged lifting jack (23), and the lifting jack (23) is used to drive the steel box beam segment to be lifted and lowered; the push rear seat (13) is also connected to a steel strand guide frame (5) for guiding the steel strand (4); The rear anchor system comprises a lifting leg (17), one end of the lifting leg (17) is connected to the middle cross beam (3), and the other end is located on the top surface of the box beam, the box beam is slidably connected to a hanging leg (19), and a corbel (20) is connected below the middle cross beam (3); The following steps are involved: Step 1: After the beam concrete is poured and cured, tensioning and corresponding cable installation are carried out, and the cantilever pouring bridge-building machine is moved to the top of the beam concrete to complete the anchoring; Step 2: remove the uppermost heightened and reinforced beam section of the main beam (1); remove the sling (21) and the sling rod in the middle part of the upper crossbeam (2), and retain the side force-bearing rod system; lift the upper crossbeam (2), and install a sling point adjustment mechanism on the main beam (1) to adjust the sling point; Step 3: Make a corbel (20) on the top of the hanging leg (19), disassemble and separate the hanging leg (19) and the middle cross beam (3), so that the corbel (20) is located below the middle cross beam (3), and a running track (18) is pre-embedded and welded on the flange plate, and the hanging leg (19) can move in the running track (18); after the upper cross beam (2) is lifted, the lifting bracket cross beam (26) and the support leg are disassembled, and the remaining full-length middle cross beam (3) is connected and fixed to the main beam (1) to form a stable whole; the lifting support leg (17) is moved to the inner side of the outermost main beam (1) and the two sides of the main beam (1) at the middle position, and installed below the main beam of the lifting bracket; at the same time, the steel box beam section is processed; Step 4: Install a lifting mechanism on the main beam (1) to realize the lifting of the steel box beam. At the same time, a hydraulic station is set on the beam surface between the main beams (1) of the bridge-building machine to provide power for the lifting jack (23) and the jack (6); install a lifting device at the front end of the lifting mechanism, connect the lifting device to the steel box beam, and then lift the steel box beam through the lifting mechanism to complete the installation of the steel box beam.

2. The modification method of a steel box girder cantilever crane based on a cantilever pouring bridge-building machine according to claim 1 is characterized in that: The sling comprises an adjustment sleeve (8) connected to the steel strand (4); the adjustment sleeve (8) is detachably connected to a sling main beam (10); the sling main beam (10) is movable within the adjustment sleeve (8); the sling main beam (10) is connected to at least one shoulder beam (15); the shoulder beam (15) is movable along the main beam (1).

3. The modification method of a steel box girder cantilever crane based on a cantilever cast-in-place bridge-building machine according to claim 2 is characterized in that: The steel strand (4) is connected to the adjustment sleeve (8) via an anchor, and a jack (6) for adjusting the center of gravity of the lifting point is also connected to the main beam (10) of the lifting device, and the jack (6) is connected to the anchor.

4. The modification method of a steel box girder cantilever crane based on a cantilever cast-in-place bridge-building machine according to claim 1 is characterized in that: The walking system comprises a track beam (9) located below the main beam (1), and the main beam (1) can move along the track beam (9); and also comprises a jack (6) for driving the main beam (1) to move.

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