CN107055347B - A kind of Tower crane disassembly structures and methods of high-rise installation - Google Patents

Abstract

The invention discloses a tower crane disassembly structure and method for high-rise installation. By adopting a cantilevered steel beam structure outside any floor of a high-rise building to fix the tower crane and the roof crane, the installation structure is novel, and the "herringbone"-shaped high-rise building is overcome. There is no way to install tower cranes and roof cranes at the top due to structural defects. Choose to install and fix tower cranes and roof cranes by installing cantilevered steel beams from the floor where construction operations are required. After the tower crane completes its work, it can be disassembled by roof cranes. The fixing method is simple. , novel, and can be installed on the outside of any floor, with strong installation flexibility, especially for the repair of buildings whose main structure has been completed and the installation of external equipment, there is no need to install tower cranes and roof cranes from the ground, which greatly saves tower cranes and roofs Crane installation and operating costs.

Description

A tower crane dismantling structure and method for high-rise installation

technical field

The invention relates to the technical field of building construction, in particular to a dismantling method of a tower crane installed on an intermediate floor.

Background technique

Tower crane is the most commonly used lifting equipment on construction sites, also known as "tower crane". , concrete, steel pipe and other construction raw materials. Tower crane is an indispensable equipment on the construction site.

In the existing buildings, in order to save the ground area and make better use of the space, the building is usually built very high, and for the sake of beauty, the outer wall will be installed with glass. Usually, the method of installing glass is It is installed indoors and outdoors. For the installation of glass on the roof, especially the roof of the "herringbone" structure, it is generally installed by tower crane. This method must be synchronized with the construction of the main body of the building, and the tower crane is generally used. Installed on the foundation cap of the ground, fixed by pre-embedded anchor screws, and then added standard sections and attachment devices to the original standard height, due to the large size and heavy weight, if it is installed from the ground to the top of a super high-rise, many standard sections need to be installed And attachment frame, if a small-scale construction project is carried out, installing a tower crane from the ground will waste a lot of manpower, material and financial resources, time-consuming and labor-intensive, and for some structures that have already built the main body of the building, and the roof cannot be installed with tower cranes and roof cranes, If you want to carry out high-rise construction, you need to build the foundation of the tower crane from the ground, which is extremely inconvenient. When the tower crane needs to be dismantled, you may need to use another high-rise building to build a roof crane, which is extremely inconvenient.

Contents of the invention

In view of the deficiencies in the above-mentioned technologies, the present invention provides a tower crane disassembly structure that can be installed on the outside of any floor in a high-rise building, and a dismantling method for the tower crane, mainly for high-rise buildings with a "human" roof. The glass installation of the font-shaped building does not need to install tower cranes and roof cranes from the ground, which greatly saves the cost of disassembly.

In order to achieve the above object, the present invention provides a dismantling structure of a tower crane installed in a high-rise. A steel girder structure, the cantilevered steel girder includes an upper box girder, a lower box girder, a diagonal brace, H-shaped steel and a fastening device, and the upper box girder extends from the core of the building to the edge of the building To the outside of the building wall, the lower box girder extends from the core position of the building to the edge of the building, and the edge position of the upper box girder and the building and the edge position of the lower box girder and the building are fixed by fastening devices. H-shaped steel, the end point of the extension section of the upper box girder and the edge of the lower box girder and the building are connected with a diagonal brace, two of the upper box girder and the lower box girder are provided, and the two The two upper box girders are arranged in parallel on the horizontal plane, the two upper box girders and the lower box girders are arranged in parallel in the vertical direction, and a reinforced plate is fixed between the two upper box girders, and the roof The four legs of the suspension base are installed on the extensions of the two upper box girders.

Wherein, the fastening device includes a U-shaped hoop, a first bolt-fixed structure and a second bolt-fixed structure, and the connection mode between the upper box girder and the building is the first bolt-fixed structure and the second bolt-fixed structure, The connection between the lower box-shaped beam and the building is a U-shaped hoop, and the U-shaped hoop fixes the lower box-shaped beam and the building through high-strength bolts and a rear pressure plate, and the first bolt fixing structure passes the upper The pressure plate is placed above the upper box girder, and the lower pressure plate is placed under the main concrete structure of the building. The upper box girder is fixed by high-strength bolts penetrating through the concrete main structure and the upper pressure plate and the lower pressure plate. Among them, the upper box A rib plate is provided inside the shaped beam to enhance the supporting capacity, and a footboard is clamped between the upper box-shaped beam and the concrete main structure, and the upper box-shaped beam extends out of the building, and the angle formed by the upper box-shaped beam and the building is position, and an anti-backward device is also provided. The upper platen of the second bolt-fixed structure is placed above the upper box girder, the lower platen is placed below the concrete main structure, and the footing plate is clamped between the upper box girder and the concrete main structure. Between them, high-strength bolts penetrate the upper plate and the lower plate to fix the upper box girder, and a reinforcing rib is arranged behind the upper box girder.

Wherein, the legs of the roof hanging base are welded on the upper box girder by carbon dioxide, and the place where the roof hanging base contacts the upper box beam is also provided with reinforcing ribs. In order to better support the entire roof hanging, the The lower end of the reinforced plate is also fixedly installed with an inner support connecting beam through a hinged manner, and a horizontal connecting beam is arranged at the ends of the two outwardly extending upper box beams.

The invention discloses a dismantling method of a high-rise installed tower crane, which is provided with the dismantling structure of the above-mentioned high-rise installed tower crane, and both the tower crane and the roof crane are installed between the floors of a high-rise building, and the dismantling steps are as follows: first install a Attachment device, drop joint, use wire rope to stabilize the tower crane; then remove part of the counterweight, the remaining two counterweights, install the roof crane on the boom, remove the boom at the front end of the boom, and then disassemble the boom of the boom For the front tie rod, remove one of the counterweights after removing the front section of the boom, and remove the last piece of counterweight after removing the rear part of the boom; then remove the balance arm, driver's cab, transition joint, upper slewing, and slewing in sequence Ring gear, lower slewing, remove the jacking platform and jacket frame, remove the remaining standard sections, and finally remove the foundation steel beam and cantilever steel beam.

Among them, in the steps of installing the attachment device and lowering the tower, the roof hoisting boom is first turned to the outside of the building, and the balance arm is facing the direction of the building, forming a 90-degree angle with the tower crane to prevent the tower crane from lifting the standard section down. Collision occurs during the process, and then start to drop the standard section to the last attachment position, remove the attachment device and then lower the section, remove the lower attachment device and lower the tower crane to the last 3 standard sections, and connect the tower body and the building with the steel wire rope Connection, the connection method adopts the two main rods on the inside of the standard section of the tower body to wrap around the steel wire rope and pull it on the connecting steel beam of the building at 45 degrees to the outside, and then dismantle it in the order of dismantling the tower crane.

Among them, in the dismantling step of the boom, the luffing trolley and the luffing assembly are first disassembled to the ground with the roof crane, and then the roof crane is installed on the lower chord at the front end of the tower crane boom with the luffing trolley, and the The outriggers of the roof crane are clamped on the lower chord, and at the "herringbone" intersection point at the upper end of the roof crane, the steel wire rope is used to pull it obliquely backward on the upper chord, and the chain hoist is used in the middle to control the amplitude of the roof crane. The hoisting mechanism is replaced by a steel wire rope, and the roof crane swings away from the edge of the building. When the tower crane boom is disassembled, the roof crane boom is turned outward for a certain distance, and the tower crane boom is rotated 90 degrees to the right. For the descending work, according to the lifting performance of the roof crane, the front section of the boom is cut off in the air, and then the boom at the rear section is disassembled as a whole.

Among them, in the step of disassembling the balance arm, after the disassembly of the jib is completed, the jib of the tower crane is turned 90 degrees to the left. In the reinstallation area, cover the safety net and tighten it. Use four lifting ropes of the same length to connect the four corners of the lifting winch with the shackles and the lifting rings. Lift the roof hook until the lifting rope is stressed, and then pull out to connect with the winch. The pin shaft of the lifting winch is hoisted to the ground and the balance arm is disassembled as a whole.

Wherein, it is characterized in that it also includes the disassembly step of the tower cap. During the disassembly process of the tower cap, two cloth straps are used to fasten the hanging ears on the top of the tower cap, and after the cloth straps are tightened, the connecting bolts between the tower cap and the transition section are loosened. If the connecting bolts are loose, use a special electric wrench for dismantling the tower crane to carry out lever hitting. After the nut is loose, twist it by hand to remove it, and use an electric wrench to remove the connecting bolt. The lower glass curtain wall; after the tower cap is removed, start to disassemble the transition section and the driver's cab in the same way, and the removal of the driver's cab is relatively simple.

Among them, during the dismantling process of the slewing tower, the upper and lower supports and the slewing mechanism, four lifting wire ropes of the same length are tied to the four connecting lugs of the upper slewing, and the steel wire ropes are tightened to the state of stress, and they are fully paved in the lower slewing in advance. Wooden board, loosen and remove the rotary connection with high-strength bolts, and then remove the rotary ring gear. When hoisting the rotary ring gear, use a crowbar to pry up the rotary Go out, close the shackles, two steel wire ropes form diagonally, place on the ground, when disassembling the lower slewing support, use four steel wire ropes in a square form to bind respectively in the bolt holes connecting the slewing and ring gear, and connect the slewing and ring gear below. Remove the high-strength bolts connected to the standard section with a ring wrench and then stand on the slewing platform on the sleeve frame. The pin hitting method is the same as that of the lifting arm. After removing the four-corner pin connection, start lifting the lower slewing support upward. Before lifting A demolition worker observes the separation of the connection between the slewing and the standard section in the lower standard section of the slewing, and gives a lifting signal after confirming that it is correct. The driver of the roof crane starts to lift slightly according to the signal. After confirming that it is safe, he can turn to the left and lower the hook. Transshipment work on the ground.

Among them, during the dismantling process of the cantilevered steel beam, the two diagonal stay rods on the cantilevered steel beam are first disassembled with the roof crane, and then the two hoisting rope bolts are hung on the lugs at both ends of the cantilevered steel beam, and the steel wire rope is stressed. Finally, in the middle of the vertical column, remove the connecting pin shaft between the lower support rod and the fixed support. Before removing the connecting pin shaft, use a steel wire rope to connect the diagonal tie rod with the wall of the opposite core tube, and hang a bolt on the end of the steel wire rope. Chain hoist, use the chain hoist to control the outward impact of the diagonal strut. After hitting the pin shaft, loosen the chain hoist slowly until the diagonal strut is in a vertical state, and release the tension between the wire rope and the chain hoist. To connect, loosen the bolts of the rear cover plate of the U-shaped hoop on the pre-installed scaffolding platform, and remove the cover plate. After the cover plate is disassembled, the roof hanger turns slightly to the left, so that the U-shaped hoop is detached from the concrete column and then accelerates down. Hook to ground for transfer.

The beneficial effects of the present invention are:

Compared with the prior art, the tower crane dismounting structure of the high-rise installation of the present invention has a novel installation structure, overcomes the defect that the tower crane and the roof crane structure cannot be installed from the roof of the "herringbone" high-rise building, and chooses to carry out construction operations from the need The floors are installed and fixed with tower cranes and roof cranes by installing cantilevered steel beams. After the tower crane completes the operation, it is disassembled by the roof crane. The fixing method is simple and novel, and can be installed on the outside of any floor. The installation flexibility is strong, especially For the repair of buildings whose main structure has been completed and the installation of external equipment, there is no need to install tower cranes and roof cranes from the ground, which greatly saves the installation and operation costs of tower cranes and roof cranes.

Description of drawings

Fig. 1 is the structural representation that tower crane and roof crane of the present invention are fixed on the building;

Fig. 2 is a schematic diagram of the installation structure of the roof crane foundation steel beam according to the embodiment of the present invention;

Fig. 3 is the first bolt fixing structure of the embodiment of the present invention;

Fig. 4 is the second bolt fixing structure of the embodiment of the present invention;

Fig. 5 is a schematic diagram of the structure of a U-shaped hoop according to an embodiment of the present invention;

Fig. 6 is a structural schematic diagram of a roof crane dismantling a tower crane according to an embodiment of the present invention;

Fig. 7 is a diagram of the steps of dismantling the tower crane from the roof crane according to the embodiment of the present invention.

Detailed ways

In order to express the present invention more clearly, the present invention will be further described below in conjunction with the accompanying drawings.

Please refer to Fig. 1-Fig. 2. The present invention discloses a dismantling structure of a tower crane installed in a high-rise. Cantilevered steel girder structure. The cantilevered steel girder includes an upper box girder 31, a lower box girder 32, a diagonal brace 33, H-shaped steel 34 and fastening devices. The upper box girder 31 runs from the core of the building to the edge of the building. Extending to the outside of the building wall, the lower box girder 32 extends from the core position of the building to the edge of the building, and the upper box girder 31 and the edge position of the building and the lower box girder 32 and the edge position of the building are fixed by fastening devices H-shaped steel 34 is arranged, and the end point of the extended section of the upper box-shaped beam 31 is connected with a diagonal brace 33 between the edge of the lower box-shaped beam 32 and the building. Both the upper box-shaped beam 31 and the lower box-shaped beam 32 are provided with two , and the two upper box girders 31 are arranged in parallel on the horizontal plane, the two upper box girders 31 are arranged in parallel with the lower box girder in the vertical direction, and a steel bar is also fixed between the two upper box girders, the roof Four supporting legs of hanging 1 base are installed on the extensions of two upper box girders 31.

The structure installed on the ground with the existing tower crane 2 and roof crane 1 saves the installation cost and labor cost of tower crane 2 and roof crane 1. At the same time, it overcomes the difficulty of installing tower cranes from the roof of "herringbone" high-rise buildings 2 and the structural defects of the roof crane 1, choose to install and fix the tower crane 2 and the roof crane 1 by installing cantilevered steel beams from the floor where construction operations are required. After the tower crane 2 completes the operation, it is disassembled by the roof crane 1. , novel, and can be installed on the outside of any floor, with strong installation flexibility, especially for the repair of buildings whose main structure has been completed and the installation of external equipment, there is no need to install tower crane 2 and roof crane 1 from the ground, which greatly saves tower cranes 2 and the installation cost and operating cost of roof crane 1.

Please refer to Fig. 3-Fig. 5, in the present embodiment, fastening device comprises U-shaped hoop 353, first bolt fixing structure 351 and second bolt fixing structure 352, the connection mode of upper box girder 31 and building is The first bolt fixing structure 351 and the second bolt fixing structure 352, the connection mode between the lower box girder 32 and the building is a U-shaped hoop 353, and the U-shaped hoop 353 connects the lower box-shaped The beam 32 is fixed to the building, and the first bolt fixing structure 351 is placed on the top of the upper box beam 31 by placing the upper pressing plate 3511, and the lower pressing plate 3512 is placed below the main concrete structure of the building, and the two are penetrated by high-strength bolts 4 The concrete column structure and the upper pressing plate 3511 and the lower pressing plate 3512 fix the upper box beam 31, wherein the upper box beam 31 is provided with a rib plate 311 to enhance the supporting capacity, and there is a gap between the upper box beam 31 and the main concrete structure. The footing plate 3513 is clamped, the upper box beam 31 extends out of the building, and an anti-backward device 3514 is also provided at the angle between the building and the building, and the upper pressing plate 3521 of the second bolt fixing structure 352 is placed on the upper box beam. Above the beam 31, the lower pressure plate 3522 is placed under the concrete main structure, the footing plate 3523 is clamped between the upper box beam 31 and the concrete main structure, and the high-strength bolts 4 penetrate the upper pressure plate 3521 and the lower pressure plate 3522 to connect the upper box beam 31 is fixed, and at the rear of the upper box beam 31, a reinforcing rib 3524 is provided.

Please refer to Figures 6-7, in this embodiment, the legs 11 of the roof crane 1 base are welded on the upper box beam 31 by carbon dioxide, and the place where the roof crane 1 base contacts the upper box beam 31 is also set There are ribbed plates, in order to better support the entire roof crane 1, the lower end of the reinforced plate is hinged, and the inner support connecting beam is fixedly installed, and the ends of the two outwardly extending upper box girders 31 are set There are horizontal connecting beams.

In this embodiment, its specific disassembly process is, taking the disassembly of a high-rise building with a "herringbone" roof as an example, the tower crane 2 is installed on the main body of the 48th floor, and the above-mentioned tower crane 2 disassembles the basic steel beam of the structure, Before installation, a 1200*700*30mm thick iron plate is placed on the edge of the concrete structure where the steel beam is erected between the A-B axis of the 48th floor to prevent direct contact between the foundation steel beam and the concrete and to increase the resistance of the concrete structure below the steel beam. Compressive capacity, 400mm wide steel beam and concrete contact surface is small and easy to crush the concrete structure. Double-sided 5000*360*25mm double-sided long ribs are used to enhance the bending moment of the cantilevered steel beam when the foundation steel beam crosses the No. 8 axis of the building;

Before the steel girder foundation cantilever outwards, connect the upper end of the lower support rod with the pin shaft of the steel girder lug plate, fasten the lower end with a Φ12 steel wire rope, and connect the other end of the steel wire rope with the hand chain hoist on the building, and use a tower crane to lift the foundation steel girder Lift upwards, tighten the chain hoist, pull the lower end of the lower strut into the No. After the predetermined position (the center of the No. 8 axis on the 47th floor), use 4 M48*1600 wall-through bolts to fix the upper and lower iron plates with the building. After the installation of the two cantilevered steel beams is completed, connect the outer horizontal connecting rods, and then fix the diagonal braces 33 of the two cantilevered steel beams to fix the left and right stability of the foundation steel beams, because the diagonal braces 33 cannot be installed outside the left foundation steel beam , so the diagonal struts 33 are installed in the internal measurement of the foundation steel beam, and the two diagonal struts 33 form a scissors brace diagonally. Both the horizontal tie rod and the diagonal brace 33 are connected by pin shafts at both ends, and the diameter of the pin shaft is Φ50. The ear plate connecting the inner strut to the building is fixed on the outer side of the concrete beam. Because the thickness of the 8-axis beam is relatively large, M24*500 is used. *The 8.8-grade high-strength bolts are fixed on the building by planting reinforcement. The national standard 400*400*20*4000 type H-shaped steel 34 is used for backing up at the clamping position between the 8-axis concrete structure and the steel beam, and the lower end of the H-shaped steel 34 is used as a footboard with a 30mm steel plate, and the connection method is the same as that of the upper layer.

In order to control the backward or forward sliding of the foundation steel beam under the force of the roof crane 1, a 200*400*30 type restricting device is vertically welded on the outside of the intersection of the lower end of the steel beam and the 8 axis, and the restricting device reaches the concrete of the building After the outer edge of the structure, three triangular reinforced strong plates are welded at the joint between the steel beam and the footing plate at the intersection of the 7-axis and the steel beam, and the four bolts of the footing plate are used to control the sliding of the steel beam to the outside.

A safety platform is built horizontally on the foundation steel beam with scaffolding steel pipes, and protective railings with a height of not less than 1.8 meters are erected on three sides of the platform. The platform is 6 meters, and each side has 1 meter of operating space, which meets the construction requirements.

In order to prevent rollover caused by force on one side of the cantilevered construction platform, the steel pipe and the cantilevered platform are bound with 8# iron wires in multiple ways to connect the full bedding, and then the upper layer is compressed with steel pipes to ensure that the horizontal operation platform is safe and correct. The horizontal overall moso bamboo rake must not have suspended phenomenon or the suspended point shall not exceed 20 cm. Multiple people must check that the installation platform and protective railing are firm and reliable. The safety belt suspension point is composed of Φ13mm steel wire rope and 120*120*2000 square tube. The specific method is to vertically weld the square tube to the front end of the operation platform, and horizontally bolt the steel wire rope to the structural column at the upper end of the vertical square tube. In the middle of the safety wire rope, more than 4 safety rings are made by using the head lock ring method, and the seat belt connection point is buckled in the safety ring. Even if the outer end of the safety wire rope falls off due to other reasons, it will not affect the protection work of the safety belt. A high-altitude fall accident occurred. After the foundation installation of the roof crane 1 is completed, the installation of the roof crane 1 will be carried out after the inspection and acceptance by the Quartet.

In this embodiment, a 12T roof crane 1 is used to disassemble the tower crane. The foundation of the 12T roof crane 1 cannot be installed on the original building. Consider two 15000*400* beams hanging outward on the beam plate surface between the A-B axis of the 48th floor. 400 box girders, the box girder protrudes 6 meters outside the building, and the edge of the building is 9 meters inward. The Φ152*16mm seamless steel pipe is used as a diagonal brace between the 47-story building and the outer cantilever. Install the 12T roof crane 1 on the outside of the cantilevered steel beam. The basic size of the 12T roof crane 1 is 3800*4400mm, that is, the distance between the outer edge of the building and the center of the roof crane 1 is 3500mm. Use the installed 12T roof crane 1 to install an attachment device 7 meters above the foundation of the tower crane to stabilize the stability of the tower crane after removing the previous attachment. Then use the 12T roof crane 1 to remove 4 pieces of tower crane counterweights (3 pieces of 1.64T, 1 piece of 1.0T), leaving one piece of 1.64T and one piece of 2T counterweight. After removing the boom, gradually remove the tower cap, upper rotation, Ring gear, lower slewing, sheath platform, sheath and standard parts and foundation steel beams, etc.

After the disassembly of the tower crane is completed, use the 12T roof crane 1 to hoist the base of the 6T roof crane 1 on the 48th floor at a position offset by 2 meters from the A axis to the B axis. The footing plate and the concrete building beam are clamped by 4 M48*8.8 high-strength bolts, and the upper end is welded to the outside of the horizontal connecting beam to stabilize the vertical H-shape left and right swing. 300*300*16 H-shaped steel 34 inclined type and 7-axis beam surface are pre-clamped on the inner side of the vertical H-shaped steel 34, and the fixed base is connected with the lug plate, and the horizontal beam and vertical H-shaped steel 34 are added due to the 6T roof crane 1 The change of the outward hoisting moment caused by the hoisting, the outward pulling force of the 6T roof crane 1 diagonal stay rod is 7 tons, and the downward pressure is 4 tons, and the building can bear both the pulling force and the pressure. After the 12T roof crane 1 is disassembled, the foundation steel beams are cut and transferred to the ground. When disassembling the 6T roof crane 1, first hang a 5T*10m long chain hoist on the top of the 6T roof crane 1, use the chain hoist to adjust the 6T roof crane 1 to the 48th floor, the boom is divided into 9 sections, and the hoist is divided into pieces Use a manual forklift to transport it to the ground by an indoor elevator, and finally clean up the site to complete the demolition work.

The specific operation is:

For the installation of attachment devices: In this embodiment, the tower crane to be dismantled adopts a cantilevered steel frame beam foundation without foundation weight, and the weight of the foundation itself cannot reach the overturning force of the control tower crane. The original design is 13 meters above the foundation An attachment device with 4 tie rods is installed at the place. When the tower crane is lowered to the attachment position, the tower crane boom is still 21 meters high from the foundation, and the overturning moment of the tower crane is still a bit large. An attachment device is installed 7 meters above the foundation section, and the connection point of the attachment rod is placed on the column of the vertical steel structure of the main structure. The original installation and the tensile structure inside the column remain unchanged. Lower the joint to 7 meters and then attach the attachment device until the tower crane is lowered to 3 standard joint heights (8.4 meters). Before dismantling the tower crane, install an attachment device with four tie rods 7 meters above the foundation of the tower body, so as to stabilize the stability of the tower crane after dismantling the upper attachment. Turn the boom of the roof crane 1 to the outside of the building, and the balance arm is facing the direction of the building, forming a 90-degree angle with the tower crane to prevent the tower crane from colliding during the process of lifting the standard section down. Then start to drop the standard section to the last attachment position, remove the attachment device and then lower the section to 7 meters, remove the lower attachment device and lower the tower crane to the last 3 standard sections, and connect the tower body to the building with a Φ20mm steel wire rope , the connection method adopts the two main rods on the inside of the standard section of the tower body to wrap around the steel wire rope and pull it on the connecting steel beam of the building at an angle of 45 degrees to the outside, and then dismantle it in the order of dismantling the tower crane.

During the lowering process of the tower crane, the actions should be coordinated and unified. When the jacking cylinder is in place, the two people each look at a step. After confirming that it is safe, they can operate the cylinder control valve to lift upwards. Cylinders can be collected. When the standard section is drawn out, personnel are prohibited from standing outside the standard section. After confirming safety and wearing the seat belt correctly, they can hook and go to the lead-in wheel on the platform.

Disassembly of the counterweight: QTZ80.12 roof crane is used for the disassembly operation. After the tower crane is lowered to the minimum, the boom of the roof crane 1 is turned to the right, and the boom is one meter away from the balance arm of the tower crane. Stop the slewing, and control the slewing speed to the minimum during the slewing process to prevent the roof crane 1 boom from colliding with the tower crane's balance arm due to the inertia force of the roof crane 1 boom. Slowly change the amplitude outward. At this time, the hook of the roof crane 1 is at the highest lifting position. The lifting rope is carried out with a sling with a length of 1 meter and a lifting capacity of 3T. The weight of the first counterweight is 1000KG, and the maximum range of the roof crane 1 is allowed to lift 2.7T, which meets the hoisting requirements. The center of the hook of the roof crane 1 is vertical to the last counterweight ring, and the hook is lifted upward until the lower end of the counterweight is higher than the balance arm railing, then turned 180 degrees to the left, and then lowered to the ground. Remove other counterweights in the same way, leaving the last 2T and 1.64T counterweights on the balance arm. After dismantling the 20-meter boom at the front end, the 1.64T counterweight is lifted, and the last 2T counterweight is lifted after the boom is completely dismantled. During the counterweight hoisting process, the position of the balance arm that has been hoisted with the counterweight is a hollow position. Pay attention to prevent people from falling from the hollow position. The safety belt must be hung in a safe and effective place where there is no possibility of collision, such as the middle position of the diagonal stay. etc. If the length of the safety belt suspension rope is not enough, you can consider lengthening the rope of the same specification and quality or choose to wear a safety rope with a length of 3 meters to ensure safe construction.

The specific disassembly method is as follows:

The tower crane has a height of 8.4 meters behind the tower body, 12.4 meters with the slewing assembly and transition joint, the effective hoisting distance from the rear end of the balance arm to the roof crane 1 is 21.5 meters, and the allowable hoisting capacity is 3T, which meets the hoisting requirements. working conditions.

The sling for 1 roof hoist uses a 5T hoisting special cloth belt or steel wire rope, and the connection between the sling and the counterweight ring is connected by a 5T shackle, and one piece is hoisted each time.

Rotate the boom of the roof crane 1 to the upper part of the counterweight at the end of the balance arm of the tower crane, adjust the verticality between the hook and the last counterweight, connect the sling to the counterweight with the lower hook, and then tighten the hoisting load , observe whether the counterweight pin is stuck, and then lift up after confirming safety, pay attention to observe that there is no friction between the counterweight and the balance beam as much as possible, and prevent the small hard pieces of the concrete block at the corner of the counterweight from colliding with the balance. Slamming on the glass of the curtain wall below causes damage to the finished product.

When the counterweight is lifted upwards, observe the stability of the tower body and the tension of the cable-stayed wire rope and whether the corner guards fall off and damage the wire rope.

After the first counterweight is lowered to the ground, when hoisting the second counterweight, hoist 10 cm from the roof and swing the boom outward to separate the two counterweights, between the two counterweights Put a wooden square horizontally, and two people stand on the platforms on both sides, holding the wooden square to prevent the counterweights from colliding with each other. In the same way, remove the four counterweights and leave a 1.64T and 2T counterweight on the balance arm. After the 20-meter counterweight is disassembled, a 1.64T counterweight is removed, and the last 2T counterweight is disassembled after all the jibs are disassembled.

When the counterweight is disassembled, the safety belt of the construction personnel must be hung in a place where the fixation is limited and cannot be hit by the counterweight, such as the middle position of the diagonal stay rod, etc. If the length of the safety belt bolt is not enough, consider lengthening the bolt and lanyard with a rope of the same specification , but the overall extension size cannot be greater than 3 meters, and the connection is limited. The two safety bolt lanyards must be tied separately to prevent the safety rope from being unprotected due to a collision injury.

After all the counterweights are disassembled, cover the counterweight area with wooden squares, and connect the wooden squares to the balance arm with iron wires to prevent the wooden squares from leaving at high altitude. Double-layer safety nets are used to tighten the wooden side, and the safety nets are tightened between the iron wire and the platform to prevent falling from high altitudes and ensure safety

Lifting arm disassembly process: the distance between the edge of the tower crane to be dismantled and the center of the A axis of the building edge is 13 meters, and the roof crane 1 is 10 meters below the boom direction. The point is 21 meters, and the distance from the roof crane to the edge of the building is 3.5 meters. Due to the small distance between the roof crane 1 and the building, when disassembling the boom of the tower crane, the boom of the roof crane 1 needs to be extended to 20 meters to rotate the boom of the tower crane 90 degrees to the right. For the descending work, according to the lifting performance table of the roof crane 1, the lifting performance of the roof crane 1 cannot meet the overall disassembly requirements when the amplitude is 20 meters, so it is considered to cut off the first 20 meters of the boom in the air, and then disassemble the whole After the 25-meter boom, the roof crane 1 meets the hoisting requirements.

The specific disassembly method is as follows: firstly use the roof crane 1 to disassemble the luffing trolley and the luffing assembly to the ground, and then use the luffing trolley to install the Φ80-type 6T roof crane 1 on the lower pole at the front end of the 8th section of the tower crane , use a splint to clamp the 6T roof crane 1 leg on the lower pole, and use a Φ18mm steel wire rope to pull it obliquely backward on the upper pole at the "herringbone" intersection point at the upper end of the 6T roof crane 1, and use a 5T chain block in the middle to control it 6T roof crane 1 luffing, the main power system is replaced by the wire rope of the hoisting mechanism of the tower crane. Install a fixed pulley on the root of the first section of the boom and on the upper pole of the 6T roof crane 1 position, and pass the main wire rope from the tower cap pulley through the first section of the boom and the lower pulley of the picket bar to the top pulley of the picket bar Bolt down to the front of the center of the dismantled jib. The dismantled jib is detached from the pin shaft to keep the rear heavy and the front light. Use 2T Connect the chain hoist. After all the 3 connecting pins are driven out, move the 6T roof crane 1 slightly forward by 10 cm, and then loosen the 2T chain hoist until the disassembled lifting arm is completely separated from the connected lifting arm. After removing the 2T chain hoist, drive the hoisting wire rope down to the ground. Before disassembly, hang the hemp rope bolt on the root of the dismantled boom to control the rotation of the boom in mid-air to prevent accidents caused by accidents. The rotation of the boom broke the hoisting wire rope and caused an accident.

After the dismantling of the boom section 10 is completed, move the 6T roof crane 1 to the boom section 8, and then tie the sling rope of the roof crane 1 to the upper pole at 22 meters away from the boom of the tower crane. After the heavy arm is hoisted upwards by 50 cm, use the main steel wire rope of the tower crane to tighten the front tie rod on the pulley at the top of the tower cap and punch out the connecting pin (the method of hitting the pin is the same as disassembling the boom pin), slowly pull the front The pull rod is placed on the upper rod of the tower crane jib and fastened with 8# iron wire, then reinforced with 8mm steel wire rope, the connecting pin of the pull rod is removed, and the boom and segmented pull rod are hoisted by 6T roof crane 1 to Ground, the removal method is the same as that of the first section. After dismantling the 20 meters in front of the boom, loosen the roof and hang a sling, remove the counterweight at the back and leave a 2T one, and then disassemble the remaining 25 meters of the boom. The 25-meter boom is disassembled at one time. Before disassembly, the hemp rope is tied to the front end of the boom downwards to use the direction of the boom in mid-air and to prevent twisting. After the boom is separated from the pin shaft, Turn the roof crane 1 outwards and turn it slightly to the right until the boom can move to the right and move downward at 90 degrees to the original boom. Keep more than 2 people on the ground to control the direction rope. The angle between the direction rope and the ground is 60 degrees, the strength is controlled according to the direction of the boom in mid-air, so that the object being hoisted and the hook do not rotate and do not collide with buildings. Before the lifting arm is disassembled, the roots and other places that may collide with the building are wrapped with old quilts to ensure that the finished curtain wall will not be damaged.

During the dismantling of the boom, all personnel must wear safety belts with double safety protection, and the two lanyards are tied to two safety positions respectively, and the feet must stand firm, and the connection protection of 6T roof crane 1 is loosened, and the 2T hand pull When lifting the hoist, the personnel squat on the inside of the boom, the lower horizontal cover and the diagonal stay rods are covered with wooden squares and tied firmly, and the personnel sit on the wooden squares to prevent the impact force of the steel wire rope from hurting the construction personnel. Before the pin shaft is hit, connect the cotter pin with the diagonal stay rod with an iron wire, and then gently tap the cotter pin with a small hammer to remove the cotter pin. After the cotter pin is removed, use 10# iron wire to pass through the hole of the cotter pin and tie it tightly. Knock a few times until the pin shaft is level with the lower yan rod, then tap it with a small hammer, and another person supports one end of the pin shaft with the palm of the outside of the hyun rod to prevent the pin shaft from falling off due to excessive impact force. During the alternate use of the big and small hammers, two people hold the hammer handle tightly, and fasten the small safety rope tied to the root of the hammer handle to the lifting arm to prevent the sledgehammer from dropping its hand and hitting the glass curtain wall below.

Remove the balance arm: Roof crane 1 turns to the counterweight area of the balance arm. After disassembling the last 2T counterweight to the ground, turn the balance arm of the tower crane to the direction of roof crane 1. The center lifting point of the balance arm is at a distance from the center of roof crane 1. It is 9 meters, and 9T is allowed within this hoisting range. However, considering that the lower area needs to be changed outward after the object is hoisted, it is considered to disassemble and disassemble the hoisting hoist and the balance arm. The lifting mechanism weighs 1210KG.

When disassembling the hoisting hoist, connect four hoisting ropes of the same length to the four corners of the hoisting hoist with shackles. The hooks are slightly stressed. After hitting the two connecting pins at the front and rear of the hoisting hoist, the hooks are small. Hoist upwards, and after confirming safety, turn the lower hook to the left and place it on the ground for transfer.

The weight of the balance arm is 2251.48KG, plus the balance arm rod 300KG, the total weight is 2500KG. Hang the four-day lifting rope on the hook on the four lifting lugs of the balance arm respectively, and clean up all the movable sundries on the balance arm. The disassembled pin shaft must be returned to its original position, including the cotter pin. All tools are cleaned to the platform of the cab, leaving only a small hammer and a pair of pliers for use, but they must be held firmly.

Lift the hook of the roof crane 1 upwards, the balance arm is in the state of high rear and low front, the connection position of the balance arm rod is bent downward to the position where people can carry it on their shoulders, four demolition workers go up, and after the safety belt is hung firmly, two people carry it on their shoulders Pull down the rod, support the upper rod with one hand, hit the pin with one hand, and cover the pin with the other hand to prevent it from falling off. People help to slowly close the upper tie rod to the tower cap and fasten it with iron wire, and remove the other tie rod in the same way.

Lower the hook of the roof crane 1 to the level of the balance arm, and two people stand on the inside of the transition joint. After hanging the safety belt, remove the cotter pin connecting the balance arm shaft, and hit the pin shaft from the outside to the inside. The pin shaft prevents the pin shaft from falling off. When the pin shaft is close to withdrawing, it should be hit slightly.

After the balance arm is separated from the transition joint, the person who pulls the direction control rope on the ground changes the angle of the rope at any time to control the direction of the balance arm in mid-air. At the same time, the roof crane 1 turns to the left and lowers the hook, and places the balance arm on the ground for transfer.

Dismantling the cab: It is more convenient to dismantle the cab by using the roof crane 1. Connect the four lifting ropes of the roof crane 1 to the lifting lugs on the top of the cab respectively, put the lifting ropes into a stressed state, and then remove the gap between the cab and the tower cap. The safety protection steel wire rope, the cable connecting the cab and the balance arm has been put away and coiled in the cab when the balance arm is disassembled, and the small tools and extra accessories are placed in the corner of the cab, but they should be placed evenly, and the cab door is locked. superior. Remove the connecting pin between the cab and the platform, and hang it on the cab lugs with wire. Lift the cab upwards, and the roof crane 1 swings inward. After the cab cannot collide with the slewing, turn the hook of the roof crane 1 to the left, and place the connecting pin shaft of the cab on the ground in the cab for transfer.

Removal of the tower cap: It is relatively simple to remove the tower cap, but it must be considered that the high-strength bolts connecting the tower cap and the transition section have rusty spots, and some nuts may be difficult to loosen. When considering using oxygen for gas cutting, consider the ignition device. It can be considered to put a small amount of water or yellow sand in the iron bucket to extinguish the fire. On the four uprights of the upper rotation, consider pulling the four corners of the tarpaulin to form a net pocket. Pour a small amount of water into the net pocket to catch the fire. The tarpaulin is exposed to fire and double-layered to ensure safety.

Use two 3T cloth straps with a length of 1 meter to fasten the top lugs of the tower cap. The cloth straps are connected to the tower cap with 5T shackles. After the cloth straps are tightened, loosen the connecting bolts between the tower cap and the transition section. For loosening, use a special electric wrench for dismantling the tower crane to carry out lever hitting. After the nut is loose, twist and remove it by hand. Do not directly use the electric wrench to completely remove the connecting bolts. The nut is easy to fall off and smash under the inertia of the electric wrench socket. Bad glass curtain wall below.

Disassembly of the slewing tower body, upper and lower supports and slewing mechanism: the slewing tower body, upper and lower supports and slewing mechanism are 4.5T in total, and can be disassembled at one time in the dismantling direction of the tower body, but considering that the roof crane needs to be luffed after 1 rotation of 180 degrees Start to lower the hook at the height of 16 meters. According to the data in the lifting performance table of roof crane 1, the allowable hoisting load of 18 meters is 4.5T. Considering the wind load and safety factor at a height of 260 meters, it is decided to disassemble the upper and lower slewing bearings, that is, first Disassemble the upper support, slewing ring gear and lower support. The maximum weight is 1261KG, which can fully meet the lifting requirements.

Bind four lifting wire ropes of the same length to the four connecting lugs of the upper rotation, tighten the wire ropes to the stressed state, and spread wooden boards in the lower rotation in advance to prevent personnel and bolts from falling off and passing through the protective platform below and hitting the curtain wall glass. Two installers used a ring wrench to loosen and remove the high-strength bolts used for the rotary connection at the slewing center. The two personnel came out of the slewing center to observe whether there was a safety hazard in the lifting process of the upper slewing in the 48-story building, and lifted the hook slightly. , observe whether the upper support is completely detached from the rotary ring gear. After confirming that it is safe and correct, turn to the left and lower the hook, and place it at a designated place. Remove the rotary ring gear in the same way. Pry up the ring gear to pry up a wooden square, pass the wire rope under the ring gear, pass the wire rope from the inside to the outside, close the shackles, two wire ropes form diagonally, and place them on the ground.

When disassembling the lower slewing support, use four steel wire ropes to be tied in a square form to the bolt holes connecting the slewing and the ring gear, remove the high-strength bolts connecting the slewing and the standard joint below with a ring wrench and stand on the slewing platform on the sleeve frame , the hitting method of the pin shaft is the same as that of the boom disassembly method. After removing the connection of the four corner pin shafts, the lower slewing support is lifted upwards. Before lifting, a demolition worker observes the separation of the connection between the slewing and the standard joint in the lower standard joint. After confirming that it is correct, a lifting signal is given, and the driver of roof crane 1 starts to lift slightly according to the signal. After confirming safety, he can turn to the left and lower the hook, and place it on the ground for transshipment.

Jacket frame disassembly: Before disassembling the jacket frame, first introduce the standard section of the tower crane into the platform and the operation platform for disassembly. During the disassembly process of the platform, pay attention to the small nuts and gaskets that are easy to come off, and hang the safety belt in a stable position. Finally, grasp the wrench tightly, loosen the platform nut, and then withdraw the nut by hand. Put the removed nut and screw in a bucket to confirm that there is no falling off.

Hang the four-day hoisting rope bolt in the pin shaft hole connecting the four corners of the coat frame and the lower slewing support, lift the hook slowly upwards, observe the verticality of the hook and the tower body, and prevent the four-corner pulley from being misplaced by the hook. When the jamming phenomenon occurs, when the jacket rack is out of the standard joint height, it starts to turn to the left and lower the hook, put it in the designated position, and use the truck crane to lay down the jacket rack on the ground and then transfer it. The weight of the jacket frame is 3T, and the roof crane 1 meets the requirements for hoisting.

Disassemble the hydraulic system, jacking frame, platform and guardrail. Before disassembling the climbing frame, the jacking hydraulic system (including oil station, oil cylinder), operating platform, and introduction platform must be disassembled. The balance beam is introduced into the standard section step, and the balance beam is protected and connected with the standard section cross-web bar with a steel wire rope, so as to prevent the balance beam from slipping under the influence of external force after detaching from the jacking cylinder. Remove one end of each of the two oil pipes of the oil cylinder, and tighten the other end to the disassembled joint to protect the oil pipe from damage and hydraulic oil loss. The power cord of the gas station is coiled up and tied tightly on the motor. After the pin shaft connecting the oil cylinder and the balance beam is removed, the hoisting cloth belt is tied to the middle and upper part of the climbing oil cylinder. When the cloth belt is under force, tap the shackle of the cloth belt with a wooden square to ensure that the cloth belt is in close contact with the oil cylinder. Knock out the connecting pin on the oil cylinder, two demolition workers stand on the inside of the standard section and push out the upper part of the oil cylinder, the other two stand on the platform to stabilize the oil cylinder, the roof crane 1 rises slowly, lift the oil cylinder out of the casing and place it ground.

When disassembling the lead-in platform, tie the sling to the middle of the two side beams of the lead-in platform, press the sling until the platform is slightly tilted up, and hit the two connected pins with a small hammer until the platform is separated from the lead-in beam, and the lead-in platform is adjusted Transfer to the ground.

Use a cloth belt to pass through the two lower crossbars in the middle of the platform railing, and hang the other end on the hook. The suspension belt is slightly stressed. First remove the connecting bolts 33 on the diagonal brace under the platform. When disassembling, remove the personnel station. On the inner side of the standard section, hang the safety belt, stand on the horizontal web bar with one foot, hook the diagonal web bar of the standard section with one foot, lean out of the standard section, and remove the connecting bolts. Use a small bucket to place bolts during disassembly to prevent gaskets and nuts from falling off.

After the platform is disassembled, four steel wire ropes are hung on the four corners of the sleeve frame and tied tightly. After the steel wire rope is stressed, check whether the pulley is stuck, remove the wire rope connecting the sleeve frame and the standard joint, put away the overlord pin and hold it with an iron wire. Slowly lift up the sleeve frame, and when the height of the sleeve frame exceeds the standard section, turn the lower hook to the left to place the ground transfer work.

Dismantling of the standard section: remove the standard section and the basic section in total of 3 sections, the weight of the bottom section is 963KG, the weight of the reinforcement section is 976KG*2 sections, the total weight is 2915KG, considering the overall hoisting of 3 sections, hang 1 four rope bolts on the roof for reinforcement After the four corners of the joint, tighten the steel wire rope, hit and remove 16 M39*8.8 high-strength bolts with a ring wrench at the position of the foundation beam, lift 3 standard joints upwards, and place them on the ground, use a car crane to lay them down and transfer to the field .

Disassembly of underframe beams and cantilevered steel beams: It is difficult to disassemble the underframe beams, foundation beams and cantilevered steel beams mainly because of the suspension points of safety belts. The belt is effectively connected with the safety rope, and then a 1.3-meter-high steel pipe is welded at the end of the cantilevered steel beam, and a Φ10mm steel wire rope is tied to the upper end of the steel pipe to connect with the building. Act as a railing.

The second point of dismantling the underframe beam is the cutting of the weld seam. The fire protection measures are also carried out by adding water to the fireproof tarpaulin and the brazier device. Bending, bending the acetylene tube to prevent tempering, and controlling tempering.

The hoisting of the underframe beam and the foundation beam will not be introduced in detail, but the steps for dismantling the cantilevered steel beams will be mainly introduced: first, dismantle the two oblique tie rods above the cantilevered steel beams with the roof crane 1, and then hang the two hoisting ropes on the cantilevered steel beams. On the hanging lugs at both ends of the steel beam, after the steel wire rope is slightly stressed, remove the connecting pin shaft between the lower support rod and the fixed support in the middle of the vertical column on the 47th floor. The walls of the opposite core tube are connected, and a 3T chain hoist is bolted to the end of the wire rope, and the chain hoist is used to control the outward impact of the diagonal brace 33. After hitting the pin shaft, loosen the chain block slowly until the diagonal strut 33 is in a vertical state, and release the connection between the wire rope and the chain block. Loosen the U-shaped hoop 353 back cover bolts on the pre-installed scaffolding platform, first leave the top two (one on each side) on it, and remove the other bolts to prevent the cover when removing the top bolts Slide down and support the bottom of the cover with wooden squares or channel steel. When there is a certain gap between the cover and the column after one bolt is removed, use a wooden square to place it between the cover and the column. One person holds the cover The board is stabilized, another person removes the last bolt, and one person in the middle, a total of three people, lifts the cover board on the scaffold platform, tie the cover board with a hemp rope, and the three people pull it and place it on the ground. After the cover plate is disassembled, the roof crane 1 turns slightly to the left, so that the U-shaped hoop 353 is detached from the concrete column, and then accelerates the rotation and lowers the hook to the ground for transfer.

The advantages of the present invention are:

1) The tower crane dismounting structure of the high-rise installation of the present invention has a novel installation structure, which overcomes the defect that the tower crane and the roof crane structure cannot be installed from the roof of the "herringbone" high-rise building, and chooses to install the suspension from the floor where construction operations are required. Install and fix the tower crane and roof crane by picking steel beams. After the tower crane completes the operation, it will be disassembled by the roof crane;

2) The fixing method is simple and novel, and can be installed on the outside of any floor, and the installation flexibility is strong, especially for the repair of buildings whose main structure has been completed and the installation of external equipment, there is no need to install tower cranes and roof cranes from the ground, greatly The installation and operation costs of tower cranes and roof cranes are saved.

The above disclosures are only a few specific embodiments of the present invention, but the present invention is not limited thereto, and any changes conceivable by those skilled in the art shall fall within the protection scope of the present invention.

Claims (10)

1. A dismantling structure of a tower crane installed in a high-rise, characterized in that, the base steel beam of the tower crane is installed between the high-rise floors, and the roof crane is also installed between the high-rise floors, and the foundation structure of the roof crane adopts a cantilever Steel girder structure, the cantilevered steel girder includes an upper box girder, a lower box girder, diagonal braces, H-shaped steel and fastening devices, and the upper box girder extends from the core position of the building to the edge of the building to On the outside of the building wall, the lower box girder extends from the core position of the building to the edge of the building, and the edge position between the upper box girder and the building and the edge position between the lower box girder and the building are fixed with H section steel, the end point of the extension section of the upper box girder and the edge of the lower box girder and the building are connected with a diagonal brace, two of the upper box girder and the lower box girder are provided, and two The upper box girders are arranged in parallel on the horizontal plane, the two upper box girders and the lower box girders are arranged in parallel in the vertical direction, and a reinforced plate is fixed between the two upper box girders, and the roof crane The four legs of the base are mounted on extensions of the two upper box girders. 2. The dismantling structure of the tower crane installed at a high level according to claim 1, wherein the fastening device comprises a U-shaped hoop, a first bolt fixing structure and a second bolt fixing structure, and the upper box girder The connection with the building is the first bolt-fixed structure and the second bolt-fixed structure, and the connection between the lower box girder and the building is a U-shaped hoop, and the U-shaped hoop is connected by high-strength bolts and a rear pressure plate. The lower box girder is fixed to the building, and the first bolt fixing structure is achieved by placing the upper pressing plate above the upper box girder, and the lower pressing plate under the main concrete structure of the building, with high-strength bolts penetrating the concrete between the two. The main structure, the upper pressing plate and the lower pressing plate fix the upper box-shaped girder, wherein the upper box-shaped girder is provided with ribs to enhance the supporting capacity, and a footboard is clamped between the upper box-shaped girder and the concrete main structure, The upper box girder extends out of the building, and an anti-backward device is provided at the angle between the building and the building. The upper pressing plate of the second bolt-fixed structure is placed above the upper box girder, and the lower pressing plate is placed Under the concrete main structure, the footing plate is clamped between the upper box girder and the concrete main structure, and the high-strength bolts penetrate the upper pressing plate and the lower pressing plate to fix the upper box girder, and behind the upper box girder, a reinforcement ribs. 3. The dismantling structure of the tower crane installed in the high-rise according to claim 1, characterized in that, the legs of the roof crane base are welded on the upper box girder by carbon dioxide, and the place where the roof hanger base contacts the upper box girder There is also a reinforcing rib plate, in order to better support the whole roof crane, the lower end of the reinforcing plate is hinged, and the inner support connecting beam is fixedly installed, and the end of the two outwardly extending upper box girders is set There are horizontal connecting beams. 4. a tower crane dismounting method of high-rise installation, it is characterized in that, be provided with the dismantling structure of the tower crane of the high-rise installation described in any one of claim 1-3, and tower crane and roof crane are all installed between the floors of high-rise buildings During the period, the disassembly steps are as follows: first install an attachment device, lower the joint, and stabilize the tower crane with a wire rope; then remove part of the counterweight, leaving two counterweights, install a roof crane on the boom, and remove the front end of the boom Then remove the front tie rod of the boom, remove one of the counterweights after removing the front section of the boom, and remove the last piece of counterweight after removing the rear part of the boom; then remove the balance arm and driver's cab in sequence , transition section, removal of the upper slewing, removal of the slewing ring gear, lower slewing, removal of the jacking platform and jacket frame, removal of the remaining standard sections, and finally removal of the foundation steel beam and cantilever steel beam. 5. The tower crane dismounting method of high-rise installation according to claim 4, it is characterized in that, in installing attachment, in step of lowering the tower, first the roof hoisting boom is turned to the outside of the building, and the balance arm is towards the building direction, and The tower crane is at an angle of 90 degrees to prevent the tower crane from colliding during the lifting of the standard section, and then start to drop the standard section to the previous attachment position, remove the attachment device and then lower the section, remove the lower attachment device and place the The machine is lowered to the last 3 standard sections, and the tower body is connected to the building with a steel wire rope. The connection method is to use two main rods on the inside of the standard section of the tower body to surround the steel wire rope and pull it on the building connecting steel beam at 45 degrees to the outside, and then Follow the order in which the tower crane is removed. 6. The tower crane disassembly method for high-rise installation according to claim 4, characterized in that, in the step of dismantling the boom, the luffing trolley and the luffing assembly are first disassembled to the ground with a roof crane, and then the luffing trolley is used to disassemble the luffing trolley. Install the roof crane on the lower chord at the front end of the jib of the tower crane, clamp the roof crane outriggers on the lower chord with splints, and use a steel wire rope to pull back on the upper chord at the "herringbone" intersection point at the upper end of the roof crane In the middle, a hand chain hoist is used to control the luffing of the roof crane. The main power system is replaced by the steel wire rope of the tower crane hoisting mechanism. After a certain distance, the boom of the tower crane is rotated 90 degrees to the right for lowering work. According to the lifting performance of the roof crane, the front part of the boom is cut off in the air, and then the boom of the rear part is disassembled as a whole. . 7. The tower crane disassembly method for high-rise installation according to claim 4, characterized in that, in the step of dismounting the balance arm, after the disassembly of the boom is completed, the tower crane boom is turned 90 degrees to the left, and the balance arm Within 10 meters from the roof crane, lay the pre-prepared wooden squares on the counterweight installation area, cover the safety net and tighten it, and use four lifting ropes of the same length to connect the four corners of the hoist with shackles and rings respectively. Lift the hook of the roof crane until the lifting rope is stressed, then drive out the pin shaft connected to the hoist, hoist the hoist to the ground, and start to disassemble the balance arm as a whole. 8. The tower crane dismounting method for high-rise installation according to claim 4, characterized in that it also includes a dismounting step of the tower cap, during the dismounting process of the tower cap, fasten two cloth straps on the hanging ears at the top of the tower cap, After the cloth belt is tightened, start to loosen the connecting bolts between the tower cap and the transition section. If the connecting bolts are loose, use a special electric wrench for dismantling the tower crane to carry out lever hitting. After the nuts are loose, twist them by hand to remove them. Under the action of inertia in the electric wrench socket, it is easy to fall off and smash the glass curtain wall below; after removing the tower cap, start to disassemble the transition joint and the driver's cab in the same way, and the removal of the driver's cab is relatively simple. 9. The tower crane disassembly method for high-rise installation according to claim 7, characterized in that, during the disassembly process of the slewing tower body, the upper and lower supports and the slewing mechanism, four lifting wire ropes of the same length are used to bind the upper slewing four connection On the lug plate, tighten the steel wire rope to the state of stress, spread wooden boards in the lower slewing in advance, loosen and remove the slewing connection with high-strength bolts, and then remove the slewing ring gear, and use a crowbar to pry the slewing ring ring when hoisting the slewing ring ring Put up a wooden square, pass the steel wire rope under the gear ring, the steel wire rope is passed from the inside to the outside, and the shackles are closed. The two steel wire ropes are formed diagonally. Place them on the ground. Bundled in the bolt hole connecting the slewing and the ring gear, remove the high-strength bolts connecting the slewing and the standard section below with a ring wrench, and then stand on the slewing platform on the sleeve frame. The pin hitting method is the same as the lifting arm disassembly method. , remove the connection of the four-corner pin shaft and start lifting the lower slewing support upwards. Before lifting, a demolition worker observes the separation of the connection between the slewing and the standard joint in the lower standard section of the slewing, and gives a lifting signal after confirming that it is correct. The roof crane driver according to The signal starts to lift slightly. After confirming safety, it can turn to the left and lower the hook, and place it on the ground for transshipment. 10. The tower crane dismantling method for high-rise installation according to claim 4, characterized in that, during the dismantling process of the cantilevered steel girder, the two oblique tie rods above the cantilevered steel girder are first disassembled with a roof crane, and then the two are lifted The rope bolts are hung on the lugs at both ends of the cantilevered steel beam. After the steel wire rope is stressed, remove the connecting pin shaft between the lower support rod and the fixed support in the middle of the vertical column. Before removing the connecting pin shaft, use a steel wire rope to The diagonal stay rod is connected to the wall of the opposite core tube, and a chain block is tied to the end of the steel wire rope. Use the chain block to control the outward impact of the diagonal stay rod. After hitting the pin shaft, loosen the chain block slowly. , until the diagonal brace is in a vertical state, release the connection between the wire rope and the chain block, loosen the bolts of the rear cover plate of the U-shaped hoop on the scaffold platform that has been erected in advance, and remove the cover plate. After the cover plate is disassembled, the roof The hoist turns slightly to the left, so that the U-shaped hoop is detached from the concrete column, and then accelerates the rotation and lowers the hook to the ground for transfer.