Continuous rigid frame hanging basket aerial hanging changing and swinging moving dismantling process

Abstract

The invention provides a continuous rigid frame hanging basket aerial lifting changing and swinging moving dismantling process, and relates to the technical field of continuous rigid frame hanging basket dismantling construction. According to the process, four winches are used for four-point lifting to provide power to lower a hanging basket to a certain distance, and then two winches arranged at the position of a first beam section are used for lifting changing, pulling and swinging moving; and after being longitudinally moved to a corresponding position and lowered to the ground, the dismantled part is dismantled, loaded and transported out through cooperation of a truck crane and manual work. According to the technology, hanging basket dismantling parts are lowered to the ground after being longitudinally moved in place by means of aerial hoisting, parts such as transition sites and main trusses above a bridge floor are dismantled through a truck crane and then moved to the coverage range of the hoisting capacity of a tower crane, and the hanging basket dismantling efficiency can be effectively improved and the construction period can be saved by adopting the tower crane for hoisting and lowering; aloft work is avoided, and the safety is high.

Description

Technical Field

[0001] The invention relates to the technical field of continuous rigid frame hanging basket dismantling construction, in particular to a continuous rigid frame hanging basket aerial suspension, swing and move dismantling process. Background Art

[0002] There are usually two methods for dismantling existing hanging baskets. The first method is to use the hanging basket to retreat as a whole to the range where the tower crane can lift it, and then dismantle it one by one. The second method is to use a truck crane to dismantle it after the entire bridge is closed, and then transport it to the corresponding position via the bridge deck.

[0003] However, in some engineering projects, the length of the upper crossbeam in front of the hanging basket does not meet the retreat requirements, the distance between the outer beam hangers and the bridge deck is crossed, and the lower edge of the mid-span closure position of the project continuous rigid frame is the anchor construction range, and there is a construction tower crane directly below. Under such conditions, the existing method cannot be used to dismantle the hanging basket; therefore, a continuous rigid frame hanging basket aerial modification and swinging removal process is proposed.

[0004] After searching, the patent with publication number CN114517451A provides a method for dismantling a swing-type hanging basket, which method includes: setting embedded parts in the end of the flange plate of the last segment beam body; lowering the side form and the lower crossbeam; extending the main truss of the hanging basket, and installing the first electric hoist and the second electric hoist at both ends of the extended main truss of the hanging basket, respectively, and the first electric hoist and the second electric hoist are respectively connected with the first rope and the second rope; installing the first steering device and the second steering device at the end of the flange plate of the last segment beam body; installing the first fixed pulley device and the second fixed pulley device on both sides of the bottom of the last segment beam body; connecting the first rope to one end of the first side form through the first steering device, and connecting the second rope to the other end of the first side form in turn through the second steering device and the second fixed pulley device; dismantling the second side form; connecting the first rope and the second rope to both ends of the lower crossbeam through the first steering device and the second steering device respectively. After analysis, it is found that this scheme needs to modify the hanging basket (such as extending the main truss of the hanging basket, and installing the first and second electric hoists at both ends of the extended main truss of the hanging basket; and setting a pull rope on the side membrane) to avoid damage to the flange plate of the last segment beam during swinging; and the hanging basket parts can only be removed to the top surface of the last segment beam, etc., which cannot meet the requirements of simple and efficient removal of the hanging basket under the above working conditions. In addition, the design points of this scheme are different from the key points of the newly proposed continuous rigid frame hanging basket aerial modification, swinging and removal process. Summary of the invention

[0005] The present invention provides a process for the removal of a continuous rigid frame hanging basket by changing the hanging and swinging in the air, with the purpose of solving at least one technical problem existing in the prior art mentioned in the background technology. This process innovatively utilizes a winch to traction, and lowers the hanging basket in the air by swinging and lowering it to the ground between two anchors, and then removes it after it is lowered; this process swings and lowers some of the hanging basket components below the bridge deck, and then moves the main truss and other components above the bridge deck to the coverage of the tower crane's lifting capacity, and uses a tower crane to lower it, which can effectively improve the efficiency of the hanging basket removal and save construction time; using this process, the hanging basket is transferred to the ground for removal, avoiding high-altitude operations, with high safety, and has a wide range of promotion and application value.

[0006] The present invention provides the following technical solutions to achieve the above objectives: A continuous rigid frame hanging basket aerial modification, swinging and removal process, with construction facilities under the hanging basket, characterized in that after the last hanging section is cast and tensioned, the hanging basket is removed, and the steps include: S1: Remove the protective platform; S2: remove the inner mold; S3: Remove the bottom basket and outer mold; S4: Dismantle the main truss and traveling system; In step S3, four winches are arranged at the rear side of the hanging basket for vertically lowering the bottom basket and the outer side mold, and two winches are arranged at the position of the 1# beam section for pulling and swinging the hanging basket; the hoisting wire ropes of each winch are routed to the corresponding position of the bottom basket to tie the bottom basket firmly; the bottom basket and the side mold of the hanging basket are lowered by four-point hoisting, and the left and right end hoisting points are respectively set at the beam ends of the front and rear lower beams in the corresponding directions, and the hoisting points on both sides are arranged at an equal distance from the center of gravity; after checking that the hoisting points are firm and the winches are operating normally, the four hoisting winches at the rear side of the hanging basket are started to vertically lower the bottom basket and the outer side mold for a certain distance, and then the two winches placed at the position of the 1# beam section are started to swing obliquely and gradually lower the bottom basket and the outer side mold to the side of the construction facilities, and then the truck crane is used to cooperate with manual dismantling and loading and transportation.

[0007] In the above-mentioned large-span continuous rigid frame hanging basket aerial modification, swinging and removal process in mountainous areas, step S1 includes: S11: Dismantle the rear lower crossbeam platform; the dismantling steps include: before dismantling the rear lower crossbeam platform, lower the bottom basket by 1.5m, and personnel stand on the bottom formwork to dismantle the platform; when dismantling, first dismantle the guardrail crossbar, then dismantle the steel grating plate, and dismantle the steel grating plate from one side of the platform to the other side; after each steel grating plate is dismantled, remove the corresponding L-beam component bolts and remove the L-beam; S12: dismantling the side platform of the bottom basket; the dismantling steps include: during the process of lowering the bottom basket, using the side platform of the bottom basket as a temporary passage, and dismantling the side platform of the bottom basket after the bottom basket is lowered into place; during the dismantling, all the connecting bolts between the lower cross beam and the small longitudinal beam of the platform and the guardrail and the lower cross bar are removed, and then the components are disassembled and classified; S13: dismantling the front upper crossbeam platform; the dismantling steps include: after the bottom basket and the sliding beam structure are dismantled, the front upper crossbeam platform is dismantled; when dismantling, the guardrail crossbar is first dismantled, and transported to the top surface of the box beam through the main truss channel, and then the steel grating, guardrail uprights and bottom crossbeam are dismantled in sequence from the end of the crossbeam and the middle of the crossbeam towards the main truss; S14: Dismantling of the main truss channel: The dismantling steps include: after the front upper crossbeam platform is dismantled, loosening the connecting bolts between the front upper crossbeam platform and the main truss, and then hoisting and dismantling the entire truss.

[0008] In the aforementioned process of aerial modification, swinging and removal of large-span continuous rigid frame hanging basket in mountainous areas, step S2 includes: removing the inner mold after the tensioning of the last suspended casting section is completed; during dismantling, the inner mold and the skeleton are disassembled in the box and the box beam is manually carried out; the inner sliding beam is dragged out using a winch or a hand hoist at the closing section position or a manhole reserved at the top of the box beam.

[0009] In the above-mentioned aerial modification, swinging and removal process of large-span continuous rigid frame hanging basket in mountainous areas, in step S3, the winches are all 8t winches, and the hoisting wire rope of the winch adopts Φ22mm wire rope, and the safety factor of the breaking force of the wire rope is above 5.0; the steering pulley is firmly set at the turning point of the wire rope to prevent the wire rope from being damaged by friction with the beam surface or other components when it is lowered, and the components around the wire rope are wrapped with rubber pads to avoid damage to the wire rope; the end of the wire rope is provided with a Φ24mm lifting ring for binding the bottom basket and the outer mold.

[0010] In the above-mentioned large-span continuous rigid frame hanging basket aerial modification, swinging and removal process in mountainous areas, step S3 includes: S31: Lower the outer mold onto the bottom basket crossbeam, using the slide beam and guide beam as support; S32: Two winches are arranged at the rear side of the lower beams on both sides of the hanging basket at the upper part of the box beam, which are used to lower the bottom basket and the outer mold vertically. The wire rope of the winch of the rear lower beam is lowered to the rear lower beam through the pre-buried hole at the rear end of the guide beam to tie the rear lower beam. According to the actual situation, a steering pulley is installed at the turning corner of the wire rope; the wire rope of the winch above the front lower beam is turned through the guide wheel installed on the front upper beam to hang the front lower beam; two winches are arranged at the position of the 1# beam section to tie the rear ends of both sides of the bottom basket for pulling and swinging; S33: After the winches are installed, the crossbeam and the sliding beam boom are removed. The four winches used for lowering are operated by a dedicated person and lowered synchronously. During the lowering, a person on the ground under the box beam uses a walkie-talkie to give synchronous commands and control the four corners of the hanging basket to keep it level. S34: After the bottom basket is lowered vertically to a height of 2 / 5-3 / 5 from the ground, two winches are arranged at the position of the 1# beam section to swing the bottom basket obliquely so that the bottom of the bottom basket avoids the construction facilities. After that, a dedicated person directs and controls the six winches to slowly lower the hanging basket to the ground; S34: After ensuring that the outer mold and bottom basket are stable, release the wire rope and use gas cutting to disassemble the longitudinal beam and cross beam.

[0011] In the aforementioned large-span continuous rigid frame hanging basket aerial modification, swinging and moving demolition process in mountainous areas, step S4 includes: selecting the demolition method according to the actual situation, such as the main truss and the walking system can be retreated to the operating range of the tower crane, and the tower crane is used for demolition; if it cannot be retreated, the crane equipment is used to directly go up the bridge for demolition.

[0012] In the above-mentioned large-span continuous rigid frame hanging basket aerial modification, swinging and removal process in mountainous areas, step S4 includes: S41: Remove the suspension rod and cushion beam installed on the front upper crossbeam, and cut off the connection between the main truss and the front upper crossbeam after removal; use a tower crane or crane equipment to remove the front upper crossbeam; S42: First use a hand chain hoist to pull and fix the main truss, then cut off the positioning angle steel connecting the parallel truss and the main truss, and lift the parallel truss out of the main truss; S43: When dismantling the main truss, use a tower crane or hoist to hold the main truss, loosen the bolts connecting the front support and the main truss, remove the rear anchor beam and slowly loosen the pull chain hoist. After the main truss is hoisted stably, completely loosen the chain hoist; place the main truss on the ground, knock off the pins, and disassemble the components; S44: After the main truss is disassembled, the buckle wheel is pulled out from the track beam and disassembled.

[0013] In the aforementioned large-span continuous rigid frame hanging basket aerial modification, swinging and removal process in mountainous areas, the construction facilities are anchor construction facilities and include a construction tower crane; next to the construction facilities is the ground in the middle of two anchors.

[0014] In the aforementioned aerial modification, swinging and removal process of the large-span continuous rigid frame hanging basket in mountainous areas, before the hoisting of the winch, the construction tower crane shall be rotated to the position where the cross-impact with the lowering of the hanging basket is minimized. After the hoisting of the winch, no one shall stand or pass under the hanging basket. Only after the hanging basket is lowered to 1m from the ground can the operating personnel approach for operation.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses four winches to provide power for four-point lifting to lower the hanging basket to a certain distance, and then uses two winches arranged at the 1# beam section to change the lifting to pull and swing, and move the dismantled parts longitudinally to the corresponding position and lower them to the ground, and then use a car crane to cooperate with manual dismantling and loading and transportation. The process of the present invention uses aerial lifting to realize the longitudinal movement of the dismantled parts of the hanging basket and then lower them to the ground, and uses a car crane to dismantle and transfer, and the main truss and other parts above the bridge deck are moved back to the coverage of the tower crane's lifting capacity, and the tower crane is used to lift and lower them, which can effectively improve the efficiency of the hanging basket dismantling and save construction time. At the same time, the hanging baskets are all transferred to the ground for dismantling, avoiding high-altitude operations, and are relatively safe.

[0016] 2. The present invention is applicable to the bridge hanging basket dismantling construction where there are existing buildings directly below the hanging basket or there are no traffic conditions directly below and the hanging basket cannot be lowered vertically, and the retreat distance is too long. It has a high promotion and application value for similar projects in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The schematic diagram of the vertical layout of the hanging basket dismantling construction of the present invention Figure 1 ; Figure 2 The schematic diagram of the plan layout of the hanging basket dismantling construction of the present invention Figure 1 ; Figure 3 The schematic diagram of the vertical layout of the hanging basket dismantling construction of the present invention Figure 2 ; Figure 4 The schematic diagram of the plan layout of the hanging basket dismantling construction of the present invention Figure 2 ; Figure markings: 1-construction facilities; 2. Dropping position; 3. Hanging track; 4. Main girder of hanging basket; 5. Winch one (4 units on the rear side of the hanging basket); 6. Winch two (1# beam section); 7. Wire rope; 8. Tower crane on the right side of the anchor; 9-pulley; 10-bottom basket. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] Embodiment: a process for removing a continuous rigid frame hanging basket by swinging and moving it in the air.

[0020] In the Huajiang Gorge Bridge project, a hanging basket was used for cantilever casting. The hanging basket was a diamond-shaped hanging basket. As the length of the upper cross beam in front of the hanging basket did not meet the retreat requirements, the distance between the outer beam hangers crossed the bridge deck. In addition, as the lower edge of the mid-span closure position of the continuous rigid frame of the project was the anchor construction range, there was a construction tower crane directly below. The two existing commonly used methods (the first was to use the hanging basket to retreat as a whole to the range where the tower crane's lifting capacity could be met, and then dismantle it in sequence; the second was to use a car crane to dismantle it after the entire bridge was closed, and then transport it to the corresponding position via the bridge deck) were both unable to dismantle the hanging basket. Therefore, an innovative process for dismantling the continuous rigid frame hanging basket by aerial lifting and swinging was developed.

[0021] The core of this process is to dismantle the hanging basket by lowering and pulling it with a winch, then swinging it in the air and lowering it to the ground between the two anchors. After it is all lowered, a truck crane is used in conjunction with manual labor to dismantle it, load it into a truck and transport it out.

[0022] The principle of this process is: first, four winches are arranged at the rear side of the hanging basket for vertical lowering of the hanging basket, and two winches are arranged at the position of the 1# beam section for pulling and swinging the hanging basket. Both are 8t winches. The hoisting wire rope of the winch adopts Φ22mm wire rope, and the safety factor of the wire rope breaking force is above 5.0. A steering pulley must be set at the turning point of the wire rope to prevent the wire rope from being damaged by friction with the beam surface or other components when it is lowered. The steering pulley should be firmly fixed, and the components around the wire rope should be wrapped with rubber pads to avoid damage to the wire rope. The wire ropes of each winch are released and inserted into the corresponding steering wheels, routed to the corresponding position of the bottom basket (side mold system), and the bottom basket is tied firmly with a Φ24mm lifting ring. Four-point lifting is selected for the lowering of the bottom basket and the side mold. The left and right end lifting points are respectively set at the beam ends of the front and rear lower beams in the corresponding directions, and the two side lifting points are arranged at equal distances from the center of gravity. Among them, 4 winches are arranged at the rear side of the hanging basket for vertically lowering the hanging basket, and 2 winches are arranged at the 1# beam section position for pulling and swinging the hanging basket, which can ensure that the bottom basket can be lifted to the designated position below the rear side of the hanging basket and the 1# beam section position when the hanging basket is suspended and swung in the air; After checking that the lifting point is firm and the winch is operating normally, start the hoisting winch at the rear of the hanging basket, and lower the bottom basket vertically for a certain distance. The distance is preferably lowered to 2 / 5-3 / 5 of the height from the ground (for example, the bottom basket is lowered 70m before diagonal swinging). Then start the winch placed at the 1# beam section position for diagonal swinging. The process should be slow during the diagonal pulling process to ensure the efficiency and effect of lowering, diagonal swinging. Before lifting, rotate the construction tower crane below the anchor to the position with the least cross-impact with the lowering of the hanging basket. After lifting, no one is allowed to stand or pass under the hanging basket. After it is lowered 1m from the ground, the operator can approach and operate. Place the dismantled parts of the hanging basket on the ground in the middle of the two anchors, and use a car crane to cooperate with manual labor to dismantle and load the hanging basket. To ensure safety, operations are prohibited during construction in case of strong winds and thunderstorms, and construction is stopped when the wind force exceeds level 6.

[0023] After the bottom basket of the hanging basket is removed, the main truss system and the traveling system are removed. The main truss part on the bridge deck is retreated to the operating range of the tower crane and removed by the tower crane. The tower crane is used to hold the main truss, loosen the bolts connecting the front support and the main truss, remove the rear anchor beam and slowly loosen the pull chain hoist. After the main truss is stably hoisted by the crane, the chain hoist is completely loosened. The main truss is placed on the ground, the pins are removed, and each component is disassembled and loaded and shipped out.

[0024] Using the above principles, the construction process and operation points include the following: Construction process: construction preparation, winch arrangement, dismantling of the hanging basket electro-hydraulic system, dismantling of the hanging basket auxiliary structure, dismantling of the bottom, dismantling of the side formwork, dismantling of the inner formwork, dismantling of the bottom formwork, dismantling of the suspension system, dismantling of the front crossbeam and distribution beam of the load-bearing truss, dismantling of the load-bearing truss girders and anchoring system, and transporting to the site.

[0025] The main steps of dismantling the hanging basket are: after the last standard section is poured and tensioned, the hanging basket is dismantled. The steps of dismantling the hanging basket are: dismantling the protective platform - dismantling the inner mold - dismantling the bottom basket and the outer mold - dismantling the main truss and the walking system. The bottom mold system is divided into three parts for dismantling, namely the bottom mold, the bottom cover and the bottom basket. The bottom mold system is lowered by 4 winches, and the side mold system is lowered by 2 winches. When lowering, the winches must be synchronized and at a uniform speed, and should be directed by a dedicated person. If uneven descent is found, the brakes should be immediately braked and adjusted in time.

[0026] This process does not require any special materials for the removal of the hanging basket. The specific preferred equipment can be as follows: Serial number Device Name model unit quantity use 1 Truck crane 100t tower 2 Dismantle formwork and hanging basket 2 Electric welding machine tower 2 Iron welding 3 jack 60T tower 3 Walking in a hanging basket 4 Oil Pump tower 3 Walking in a hanging basket 5 Chain Reversal 10T tower 4 6 Cutting Machine tower 2 Template decomposition cutting 7 Oxygen Acetylene set 2 Template decomposition cutting 8 hoist 10t tower 2 Winches swing removal 9 hoist 5t tower 4 Winches swing removal 10 Pulley Block 10t set 18 Wire Rope Steering 11 Intercom tower 6 Command communication The specific steps for dismantling the hanging basket are as follows: After the last suspended casting section is poured and tensioned, the hanging basket is dismantled. The steps of dismantling the hanging basket are as follows: S1: dismantling the protective platform; S2: dismantling the inner mold; S3: dismantling the bottom basket and the outer mold; S4: dismantling the main truss and the walking system; S1: Removal of protective platform S11: Dismantle the rear lower crossbeam platform; the dismantling steps include: before dismantling the rear lower crossbeam platform, lower the bottom basket by 1.5m, and personnel stand on the bottom formwork to dismantle the platform; when dismantling, first dismantle the guardrail crossbar, then dismantle the steel grating plate, and dismantle the steel grating plate from one side of the platform to the other side; after each steel grating plate is dismantled, remove the corresponding L-beam component bolts and remove the L-beam; S12: dismantling the side platform of the bottom basket; the dismantling steps include: during the process of lowering the bottom basket, using the side platform of the bottom basket as a temporary passage, and dismantling the side platform of the bottom basket after the bottom basket is lowered into place; during the dismantling, all the connecting bolts between the lower cross beam and the small longitudinal beam of the platform and the guardrail and the lower cross bar are removed, and then the components are disassembled and classified; S13: dismantling the front upper crossbeam platform; the dismantling steps include: after the bottom basket and the sliding beam structure are dismantled, the front upper crossbeam platform is dismantled; when dismantling, the guardrail crossbar is first dismantled, and transported to the top surface of the box beam through the main truss channel, and then the steel grating, guardrail uprights and bottom crossbeam are dismantled in sequence from the end of the crossbeam and the middle of the crossbeam towards the main truss; S14: Dismantling of the main truss channel: The dismantling steps include: after the front upper crossbeam platform is dismantled, loosening the connecting bolts between the front upper crossbeam platform and the main truss, and then hoisting and dismantling the entire truss.

[0027] S2: Remove the inner mold After the last suspended cast section is tensioned, the inner mold is first removed, the inner mold and the frame are disassembled in the box, and the box beam is carried out manually. The inner sliding beam is pulled out by a winch or hand chain hoist at the closing section position or the reserved manhole on the top of the box beam.

[0028] S3: Remove the bottom basket and outer mold S31: Lower the outer mold onto the bottom basket crossbeam, using the slide beam and guide beam as support; S32: Two winches are arranged at the rear side of the lower beams on both sides of the hanging basket at the upper part of the box beam, which are used to lower the bottom basket and the outer mold vertically. The wire rope of the winch of the rear lower beam is lowered to the rear lower beam through the pre-buried hole at the rear end of the guide beam to tie the rear lower beam. According to the actual situation, a steering pulley is installed at the turning corner of the wire rope; the wire rope of the winch above the front lower beam is turned through the guide wheel installed on the front upper beam to hang the front lower beam; two winches are arranged at the position of the 1# beam section to tie the rear ends of both sides of the bottom basket for pulling and swinging; S33: After the winches are installed, the crossbeam and the sliding beam boom are removed. The four winches used for lowering are operated by a dedicated person and lowered synchronously. During the lowering, a person on the ground under the box beam uses a walkie-talkie to give synchronous commands and control the four corners of the hanging basket to keep it level. S34: After the bottom basket is lowered vertically to a height of 2 / 5-3 / 5 from the ground (here, 2 / 5-3 / 5 of the height of the hanging basket), two winches are arranged at the position of the 1# beam section to swing the bottom basket obliquely so that the bottom of the bottom basket avoids the construction facilities. After that, a dedicated person directs and controls the six winches to slowly lower the hanging basket to the ground; S34: After ensuring that the outer mold and bottom basket are stable, release the wire rope and use gas cutting to disassemble the longitudinal beam and cross beam.

[0029] When the above steps are performed, the winches are all 8t winches, and the winch hoisting wire rope adopts Φ22mm wire rope, and the safety factor of the wire rope breaking force is above 5.0; a steering pulley is firmly set at the turning point of the wire rope to prevent the wire rope from being damaged by friction with the beam surface or other components when it is lowered, and the components around the wire rope are wrapped with rubber pads to avoid damage to the wire rope; a Φ24mm lifting ring is set at the end of the wire rope for tying the bottom basket and the outer mold.

[0030] S4: Dismantle the main truss and walking system S41: Remove the suspension rod and cushion beam installed on the front upper crossbeam, and cut off the connection between the main truss and the front upper crossbeam after removal; use a tower crane or crane equipment to remove the front upper crossbeam; S42: First use a hand chain hoist to pull and fix the main truss, then cut off the positioning angle steel connecting the parallel truss and the main truss, and lift the parallel truss out of the main truss; S43: When dismantling the main truss, use a tower crane or hoist to hold the main truss, loosen the bolts connecting the front support and the main truss, remove the rear anchor beam and slowly loosen the pull chain hoist. After the main truss is hoisted stably, completely loosen the chain hoist; place the main truss on the ground, knock off the pins, and disassemble the components; S44: After the main truss is disassembled, the buckle wheel is pulled out from the track beam and disassembled.

[0031] When following the above steps, please note the following: 1. The assembly and dismantling of the hanging basket should be carried out simultaneously while maintaining basic symmetry at both ends.

[0032] 2. The hanging basket assembly should be carried out step by step in their respective order. Safety inspection of lifting machinery and equipment should be carried out before operation. During the operation, there must be dedicated personnel on the ground and in the air to direct and guide.

[0033] 3. The assembly and disassembly of the hanging basket is an aerial operation. Each process must be carefully checked before proceeding to the next process.

[0034] 4. The top concrete surface of the box girder, especially the top surface of the web, should be smooth and even, and the height difference should not exceed 0.5cm to meet the requirements for the retreat of the main beam.

[0035] 5. Most of the components of the hanging basket are connected by bolts. They should be kept tight during the backward movement. The slings must be evenly stressed, the nuts must be uniformly tight, and the pads must be smooth in contact with the concrete surface. All kinds of jacks and fall chains should be guaranteed to be in good condition.

[0036] 6. When the hanging basket moves backward, the moving speed should be synchronized and consistent. Observe whether the outriggers are in the correct position and make corrections at any time.

[0037] 7. When the hanging basket is retreating, it is necessary to regularly check the cable-stayed steel belts, main truss nodes and other key components.

[0038] 8. When the hanging basket is retreating, it is a high-altitude operation, and temporary railings and safety nets should be set up for safety. Strengthen the use and management of all safety protection facilities, make good safety protection facilities and signs, have good lighting facilities for night operations, and pay attention to the safety of navigation under the bridge.

[0039] 9. During the backward movement of the hanging basket, a dedicated person should check the safety status of each component of the hanging basket. Any problems found should be reported and handled in a timely manner so that problems can be discovered and rectified in time.

[0040] 10. Keep abreast of weather conditions. During strong winds above level 5 and typhoons, operations should be stopped and corresponding preventive measures should be taken. The hanging basket must be properly anchored. It is strictly forbidden to stack other loads in front of the hanging basket.

[0041] 11. The stacking site for hanging basket components must be flat and dry, and there must be no live bare wires or high-voltage wires in the air above the stacking site.

[0042] 12. Avoid various collisions during transportation, installation and stacking.

[0043] When the above process is implemented, the quality control standards shall be carried out in accordance with the following document standards: 1. "Technical Specifications for Highway Bridge and Culvert Construction JTGT3650-2020"; 2. "Steel Structure Design Standard" (GB50017-2017); 3. "Technical Specifications for Highway Engineering Construction Safety" (JTG-F90-2015); 4. Highway Engineering Quality Inspection and Assessment Standards (JTGF80 / 1-2017).

[0044] When the above process is implemented, safety measures shall be carried out in accordance with the following document standards: 1. Construction drawing design documents; 2. "Technical Specifications for Highway Bridge and Culvert Construction" (JTGT3650-2020); 3. "Technical Regulations for Safety in Highway Engineering Construction" (JTGF90-2015); 4. "Code for Construction of Steel Structure Engineering" (GB50755-2015); 5. Technical Specifications for Safety of Hoisting in Construction (JGJ276-2015).

[0045] Specifically, the safety measures include: 1. Seriously implement the principle of "safety first, prevention first" and, in accordance with relevant national regulations and rules, combined with the actual situation of the construction unit and the specific characteristics of the project, form a safety production management network consisting of full-time safety officers, part-time safety officers of the team, and persons in charge of safe electricity use on the construction site, implement the safety production responsibility system, clarify the responsibilities of personnel at all levels, and ensure the safety of the project.

[0046] 2. The construction site shall be arranged in accordance with safety regulations and safe construction requirements such as fire prevention, wind protection, lightning protection, flood prevention, and electric shock prevention, and various safety signs shall be arranged in a complete manner.

[0047] 3. Oxygen cylinders and acetylene cylinders should be stored separately to ensure that oxygen cylinders are not contaminated with grease and that acetylene generators have safety devices to prevent backfire.

[0048] 4. Temporary power supply at the construction site shall be strictly implemented in accordance with the relevant regulations of "Technical Specifications for Safety of Temporary Power Supply at Construction Sites".

[0049] 5. The formwork removal must meet the required concrete strength at the time of formwork removal. With the consent of the engineering and technical leaders, the quality of the project must not be affected by formwork removal.

[0050] 6. Order and method of formwork removal. The order should be first support and then dismantling, then dismantling the last support and first; first dismantle the non-load-bearing formwork, then the load-bearing formwork and support; when dismantling the top plate formwork supported by small steel formwork, it is strictly forbidden to remove all the pillars and then pull and remove it at one time. The dismantled active formwork must be dismantled continuously at one time before stopping, and it is strictly forbidden to leave unsafe hidden dangers.

[0051] 7. When removing the mold, a warning area must be set up and no one is allowed to enter from below. The mold removal workers must stand on a stable, firm and reliable place to maintain their balance and must not pry violently to prevent instability and falling.

[0052] 8. It is strictly forbidden to use a crane to directly lift the formwork that has not been pried loose. When lifting large integral formwork, it must be tied firmly and the lifting point must be balanced. When lifting and transporting large steel formwork, it must be connected with a clamping ring. After it is in place, it must be pulled firmly before the lifting ring can be removed.

[0053] 9. The dismantled formwork support and other materials must be dismantled, cleaned, transported and stacked at the same time. It is strictly forbidden to throw down the materials dismantled from high places.

[0054] 10. When placing the bottom mold platform, the speed should be synchronized and uniform to prevent the template parts from twisting or bending.

[0055] 11. Before lifting objects mechanically, the safety and reliability of the mechanical equipment and ropes should be checked first. After lifting, no one is allowed to stand or pass below. Operators can only approach to operate when the object is lowered to one meter from the ground.

[0056] 12. When the bottom mold platform is lowered, the four winches must move at a uniform speed, and a dedicated person should direct the winch operators. If uneven descent is found, the brakes should be applied immediately and adjustments should be made in time.

[0057] 13. Before lifting, the lifting point must be correct and firm. When lifting, the slip rope should be fastened, and the signal command should be obeyed. Overloading is not allowed.

[0058] 14. All personnel entering the construction site must wear safety helmets and fasten their safety belts. Personnel working at heights must also fasten their safety belts. Work is prohibited in strong winds and thunderstorms.) 15. Workers who work at heights must undergo a physical examination. Those who suffer from high blood pressure, heart disease, anemia, or other conditions that are not suitable for working at heights are not allowed to engage in high-altitude work; it is strictly forbidden to work at heights after drinking.

[0059] 16. Tools used for aerial work should be placed in a tool bag. Frequently used tools should be tied to the body. Required materials or other tools must be passed with a strong rope, and it is forbidden to throw them by hand to avoid falling and injuring people.

[0060] 17. When working in places above 2m, on steep slopes or without platforms, you must wear a safety belt and hang the safety belt hook.

[0061] 18. All workers entering the construction site must wear safety helmets and fasten their hat straps. Workers working at heights must wear rubber shoes or soft-soled shoes.

[0062] 19. High-altitude operations are prohibited in winds of level 6 or above.

[0063] The above process was used in the Huajiang Gorge Bridge project: Huajiang Gorge Bridge Project Overview: The center pile number of Huajiang Gorge Bridge is K61+945, with a total length of 2890m. The structure is 5×40m first simply supported and then continuously prestressed T-beam + 1420m steel truss suspension bridge + 8×40m first simply supported and then continuously prestressed T-beam + (86+160+86)m continuous rigid frame + 15×40m first simply supported and then continuously prestressed T-beam. The rigid frame of the Huajiang Gorge Bridge approach bridge is a (86+160+86)m prestressed concrete continuous rigid frame, and the center pile number of the continuous rigid frame of the approach bridge is K63+141.800. The main pier of the continuous rigid frame of the approach bridge adopts a double-legged thin-walled hollow pier in the upper section and an integral box-type pier in the lower section. The 15# main pier is 137m high and the 16# main pier is 125m high. The transition pier adopts a hollow thin-walled pier, of which the 14# transition pier is 107m high, and the 17# transition pier is 98m high on the left and 84m high on the right. The upper box girder is a three-way prestressed structure with a single box and single chamber section. There are 19 standard cantilevered sections in the single span of the rigid frame. The length of the cantilevered section is 3.5~4.0m, and the segment length is 8×3.5m+11×4m. The height changes from 10.0m to 3.5m according to the 1.8th parabola. The heaviest cantilevered section is the 1# section, weighing 222.2t. A hanging basket is used for cantilever casting. The hanging basket is a diamond hanging basket. The removal of the hanging basket adopts the aerial swing removal method.

[0064] The construction of the continuous rigid frame of the approach bridge of Huajiang Gorge Bridge started in June 2021 and was closed in October 2023. The four pairs of hanging baskets of the rigid frame were all dismantled using this method. The removal efficiency of the hanging baskets was high and the construction period was short. The hanging baskets were all moved to the ground for dismantling, avoiding high-altitude operations and having high safety, which was unanimously praised by the project company, the general manager's office and other units.

[0065] The benefits of using this technology for the Huajiang Gorge Bridge include: 1. The swing-shift dismantling hanging basket process saves 2 days of construction time and 4 workers compared to the traditional backward hanging basket dismantling process; 2. The swing-removal and dismantling basket process uses the existing winch and wire rope, which does not consume any extra materials. Compared with the traditional process, the cost saved in this project was nearly RMB 160,000; 3. This process uses an aerial crane to move the dismantling parts of the hanging basket vertically to the ground, and uses a truck crane to dismantle and transfer the parts above the bridge deck, and moves the main truss and other parts to the range covered by the tower crane. The tower crane is used to lift and lower them, which can effectively improve the efficiency of the hanging basket dismantling and save construction time. 4. The hanging baskets are all moved to the ground for dismantling to avoid high-altitude operations. It is highly safe and has wide promotion and application value.

[0066] Obviously, the above is only a part of the embodiments of the present invention, not all of the embodiments. The above embodiments are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and variations. Any combination, modification, equivalent replacement, improvement and all other embodiments that can be made by those of ordinary skill in the art within the spirit and principle of the present invention should be within the protection scope of the present invention.

Claims

1. A process for removing a continuous rigid frame hanging basket from the air by swinging and moving, wherein there are construction facilities under the hanging basket, and the process is characterized in that after the last hanging section is poured and tensioned, the hanging basket is removed, and the steps include: S1: Remove the protective platform; S2: remove the inner mold; S3: Remove the bottom basket and outer mold; S4: Dismantle the main truss and traveling system; In step S3, four winches are arranged at the rear side of the hanging basket for vertically lowering the bottom basket and the outer side mold, and two winches are arranged at the position of the 1# beam section for pulling and swinging the hanging basket; the hoisting wire ropes of each winch are routed to the corresponding position of the bottom basket to tie the bottom basket firmly; the bottom basket and the side mold of the hanging basket are lowered by four-point hoisting, and the left and right end hoisting points are respectively set at the beam ends of the front and rear lower beams in the corresponding directions, and the hoisting points on both sides are arranged at an equal distance from the center of gravity; after checking that the hoisting points are firm and the winches are operating normally, the four hoisting winches at the rear side of the hanging basket are started to vertically lower the bottom basket and the outer side mold for a certain distance, and then the two winches placed at the position of the 1# beam section are started to swing obliquely and gradually lower the bottom basket and the outer side mold to the side of the construction facilities, and then the truck crane is used to cooperate with manual dismantling and loading and transportation.

2. The process for removing a large-span continuous rigid frame hanging basket in the mountainous area by aerial modification, swinging and displacement according to claim 1 is characterized in that: Step S1 includes: S11: Dismantle the rear lower crossbeam platform; the dismantling steps include: before dismantling the rear lower crossbeam platform, lower the bottom basket by 1.5m, and personnel stand on the bottom formwork to dismantle the platform; when dismantling, first dismantle the guardrail crossbar, then dismantle the steel grating plate, and dismantle the steel grating plate from one side of the platform to the other side; after each steel grating plate is dismantled, remove the corresponding L-beam component bolts and remove the L-beam; S12: dismantling the side platform of the bottom basket; the dismantling steps include: during the process of lowering the bottom basket, using the side platform of the bottom basket as a temporary passage, and dismantling the side platform of the bottom basket after the bottom basket is lowered into place; during the dismantling, all the connecting bolts between the lower cross beam and the small longitudinal beam of the platform and the guardrail and the lower cross bar are removed, and then the components are disassembled and classified; S13: dismantling the front upper crossbeam platform; the dismantling steps include: after the bottom basket and the sliding beam structure are dismantled, the front upper crossbeam platform is dismantled; when dismantling, the guardrail crossbar is first dismantled, and transported to the top surface of the box beam through the main truss channel, and then the steel grating, guardrail uprights and bottom crossbeam are dismantled in sequence from the end of the crossbeam and the middle of the crossbeam towards the main truss; S14: Dismantling of the main truss channel: The dismantling steps include: after the front upper crossbeam platform is dismantled, loosening the connecting bolts between the front upper crossbeam platform and the main truss, and then hoisting and dismantling the entire truss.

3. The process for removing a large-span continuous rigid frame hanging basket in the mountainous area by aerial suspension, swinging and relocation according to claim 1 is characterized in that: Step S2 includes: removing the inner mold after the tensioning of the last suspended casting section is completed; during removal, the inner mold and the frame are disassembled in the box and manually carried out of the box beam; the inner sliding beam is dragged out at the closing section position or the manhole reserved at the top of the box beam using a winch or a hand hoist.

4. The aerial modification, swinging and removal process of a large-span continuous rigid frame hanging basket in mountainous areas according to claim 1 is characterized in that: in step S3, the winches are all 8t winches, and the winch hoisting wire rope adopts Φ22mm wire rope, and the safety factor of the wire rope breaking force is above 5.0; a steering pulley is firmly set at the turning point of the wire rope to prevent the wire rope from being damaged by friction with the beam surface or other components when it is lowered, and the components around the wire rope are wrapped with rubber pads to avoid damage to the wire rope; a Φ24mm lifting ring is set at the end of the wire rope for binding the bottom basket and the outer mold.

5. The process for removing a large-span continuous rigid frame hanging basket in the mountainous area by aerial modification, swinging and displacement according to claim 1 or 4, characterized in that: step S3 comprises: S31: Lower the outer mold onto the bottom basket crossbeam, using the slide beam and guide beam as support; S32: Two winches are arranged at the rear side of the lower beams on both sides of the hanging basket at the upper part of the box beam, which are used to lower the bottom basket and the outer mold vertically. The wire rope of the winch of the rear lower beam is lowered to the rear lower beam through the pre-buried hole at the rear end of the guide beam to tie the rear lower beam. According to the actual situation, a steering pulley is installed at the turning corner of the wire rope; the wire rope of the winch above the front lower beam is turned through the guide wheel installed on the front upper beam to hang the front lower beam; two winches are arranged at the position of the 1# beam section to tie the rear ends of both sides of the bottom basket for pulling and swinging; S33: After the winches are installed, the crossbeam and the sliding beam boom are removed. The four winches used for lowering are operated by a dedicated person and lowered synchronously. During the lowering, a person on the ground under the box beam uses a walkie-talkie to give synchronous commands and control the four corners of the hanging basket to keep it level. S34: After the bottom basket is lowered vertically to a height of 2 / 5-3 / 5 from the ground, two winches are arranged at the position of the 1# beam section to swing the bottom basket obliquely so that the bottom of the bottom basket avoids the construction facilities. After that, a dedicated person directs and controls the six winches to slowly lower the hanging basket to the ground; S34: After ensuring that the outer mold and bottom basket are stable, release the wire rope and use gas cutting to disassemble the longitudinal beam and cross beam.

6. The process for dismantling a large-span continuous rigid frame hanging basket in the mountainous area according to claim 1 is characterized by: Step S4 includes: selecting a dismantling method according to actual conditions, such as using a tower crane to dismantle the main truss and the traveling system if they can be retreated into the operating range of the tower crane; if they cannot be retreated, using a crane to directly go up the bridge for dismantling.

7. The process for removing a large-span continuous rigid frame hanging basket in the mountainous area by aerial modification, swinging and displacement according to claim 6 is characterized in that: Step S4 includes: S41: Remove the suspension rod and cushion beam installed on the front upper crossbeam, and cut off the connection between the main truss and the front upper crossbeam after removal; use a tower crane or crane equipment to remove the front upper crossbeam; S42: First use a hand chain hoist to pull and fix the main truss, then cut off the positioning angle steel connecting the parallel truss and the main truss, and lift the parallel truss out of the main truss; S43: When dismantling the main truss, use a tower crane or hoist to hold the main truss, loosen the bolts connecting the front support and the main truss, remove the rear anchor beam and slowly loosen the pull chain hoist. After the main truss is hoisted stably, completely loosen the chain hoist; place the main truss on the ground, knock off the pins, and disassemble the components; S44: After the main truss is disassembled, the buckle wheel is pulled out from the track beam and disassembled.

8. The aerial modification, swinging and removal process of a large-span continuous rigid frame hanging basket in mountainous areas according to claim 1 is characterized in that: the construction facility is an anchor construction facility and includes a construction tower crane; next to the construction facility is the ground in the middle of two anchors.

9. The aerial modification, swinging and removal process of a large-span continuous rigid frame hanging basket in mountainous areas according to claim 8 is characterized in that: before the hoisting of the hoisting machine, the construction tower crane is rotated to a position where the cross-impact with the lowering of the hanging basket is minimized, and after the hoisting machine is lifted, no one is allowed to stand or pass under the hanging basket. Only after the hanging basket is lowered to 1m from the ground can the operating personnel approach to operate.

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