Construction method of super high-rise high-altitude large-span cantilever concrete structure

Abstract

A kind of construction method of super high layer high altitude large-span cantilever concrete structure, including the following steps: step one, the structure optimization and construction drawing design of cantilever concrete structure;Step two, the deepening design of measure support, measure support includes support frame and hanging basket;Step three, main body first construction;Step four, precast concrete beam section field prefabrication;Step five, the manufacture and installation of support frame;Step six: the hoisting of precast concrete beam section;Step seven: the construction of cast-in-place concrete section;Step eight: the installation of upper pull rod and lower support rod;Step nine: in turn remove hanging basket, hanging platform and support frame.The present application solves the technical problems of complex construction technology, long construction period and high construction risk of large-span cantilever structure.

Description

A construction method for a super high-rise, large-span cantilevered concrete structure Technical Field

[0001] This invention belongs to the field of building construction technology, and specifically relates to a construction method for a super high-rise, large-span cantilevered concrete structure. Background Technology

[0002] With the rapid development of society and economy, people have higher and higher requirements for the appearance, shape and function of buildings in the architectural design process. This has led to the frequent appearance of structural forms with complex on-site construction technology and long construction period, such as ultra-high large formwork structures, large-span cantilever structures and irregular facades.

[0003] This project is a mega-frame-core tube hybrid structure with reinforced layers, consisting of 4 underground floors and 37 above-ground floors (including the machine room floor and its roof). The standard floor height is 4.35m, and the total height is 158.2m. The core tube has irregularly shaped concrete structures on both sides. On the odd-numbered floors of the tower, there are cantilevered arched concrete beams with a cross-section of 500mm x 1200mm. These beams are unslabled and approximately 10m long, with their ends 5m from the main structure. The maximum construction height of these cantilevered arched beams relative to ±0.00 is 158.2m. The main challenge in constructing this type of structure is selecting a simple and time-saving construction method while ensuring safety and quality. Summary of the Invention

[0004] The purpose of this invention is to provide a construction method for ultra-high-rise, high-span, large-span cantilever concrete structures, in order to solve the technical problems of complex construction processes, long construction periods, and high construction risks associated with large-span cantilever structures.

[0005] To achieve the above objectives, the present invention adopts the following technical solution.

[0006] A construction method for a high-rise, high-altitude, large-span cantilevered concrete structure, comprising a cantilevered arc-shaped beam, upper tie rods, and lower struts; the cantilevered arc-shaped beam is arc-shaped, with one end connected to the main structure and the other end leaving a gap between itself and the main structure; the cantilevered arc-shaped beam includes a precast concrete beam segment and a cast-in-place concrete segment; the precast concrete beam segment is connected to the main structure via the upper tie rods and lower struts, and gaps are left between both ends of the precast concrete beam segment and the main structure; the cast-in-place concrete segment connects one end of the precast concrete beam segment to the main structure, and the cast-in-place concrete segment includes a reinforcing steel frame and a cast-in-place concrete layer; the reinforcing steel frame is disposed within the cast-in-place concrete layer, and the reinforcing steel frame... One end is fixedly connected to the main structure; a steel column is provided at the connection position corresponding to the cantilevered arc beam in the main structure; a steel bracket is provided on the steel column; the stiffening steel is welded to the steel bracket; the other end of the stiffening steel extends beyond the cast-in-place concrete layer and into the precast concrete beam segment; a pre-embedded component is pre-embedded on the side of the precast concrete beam segment facing the main structure, near the end position; an upper connecting plate is provided on the outer wall of the main structure above the cantilevered arc beam, and a lower connecting plate is provided on the outer wall of the main structure below the cantilevered arc beam; an upper tie rod is pulled between the upper connecting plate and the pre-embedded component, and a lower support rod is supported between the lower connecting plate and the pre-embedded component; a fixing plate is provided on the pre-embedded component, and longitudinal slots are opened on the fixing plate.

[0007] The construction method includes the following steps.

[0008] Step 1: Structural optimization and construction drawing design of the cantilevered concrete structure: Calculate the specifications of the pre-embedded steel columns and extended steel brackets in the main structure, the internal stiffening steel and anchorage length of the cast-in-place concrete section, based on the overall structural stress requirements. In addition, determine the scope of the precast concrete beam section and the cast-in-place concrete section to ensure that the structural stress requirements and on-site construction conditions are met.

[0009] Step two, detailed design of the support measures, which include a support frame and a suspended platform. To ensure the stable and safe installation of the precast concrete beam segments, a support frame is used as the support and working platform for the precast concrete beam segments. The support frame adopts a triangular frame structure, with bidirectional diagonal bracing installed in both the vertical and horizontal directions. The support frame includes vertical support units and horizontal support units. The vertical support unit includes longitudinal bars, vertical rods, and vertical diagonal bars. The vertical diagonal bars are inclined above the top of the longitudinal bars, and the lower end of the vertical diagonal bars is connected to the top of the longitudinal bars near the outer end, while the upper end of the vertical diagonal bars is vertically flush with the inner end of the longitudinal bars. The top of the longitudinal bars, located near the outer end of the longitudinal bars... A lateral limiting plate is provided on the outer part of the vertical and diagonal rods; longitudinal strip holes are spaced apart on the surface of the lateral limiting plate; the vertical rod is supported between the vertical rod and the vertical and diagonal rods, near the inner end of the vertical rod and the vertical and diagonal rods, and the vertical rod, the vertical rod, the vertical rod, and the vertical and diagonal rods form a right-angled triangle; the horizontal support unit is provided on one side of the vertical support unit, including a horizontal rod and a horizontal and diagonal rod; the horizontal rod is connected to the lower part of the vertical rod; the horizontal and diagonal rods are connected to the end of the horizontal rod, and the outer end of the horizontal and diagonal rods is connected to the lower part of the vertical and diagonal rods; there is one set of suspended baskets, which are installed near the node position between the support frame and the outer wall of the main structure, and the suspended baskets are connected to the outer wall of the main structure through a hanging assembly.

[0010] Step 3: The main structure is constructed first. The steel columns, steel brackets, and connecting components required for the cantilevered curved beam construction are constructed together with the main structure and pre-embedded. During pre-embedding, it is ensured that the positioning, size, flatness, and verticality of the pre-embedded parts meet the design requirements.

[0011] Step 4, on-site prefabrication of precast concrete beam segments: When making precast concrete beam segments, one end of the stiffening steel frame is pre-embedded in the precast concrete beam segment.

[0012] Step 5, Fabrication and Installation of the Support Frame: The support frame is assembled on the construction site. First guardrails are set on both sides of the horizontal and diagonal bars to form passageways. Lifting rings are set on the upper surface of the vertical and diagonal bars near the top, the top of the longitudinal bars near the outer end, and the top of the horizontal and diagonal bars near the inner end. After the support frame is welded to the first guardrails as a whole, it is installed in place by a three-point hoisting method using a tower crane on site. The upper ends of the longitudinal bars, vertical and diagonal bars, and inner ends of the horizontal and diagonal bars are connected to the outer wall of the main structure through connecting components. The passageway at the top of the horizontal and diagonal bars is connected to the reserved opening on the floor.

[0013] Step Six: Hoisting of Precast Concrete Beam Segments: Before hoisting, install second guardrails on both sides of the top surface of the precast concrete beam segment, then hoist the precast concrete beam segment and place it on the support frame; make the lateral limiting plate contact the fixed plate surface, and connect the lateral limiting plate and the fixed plate by inserting bolts through the longitudinal strip holes; at the same time, temporarily fix the stiffening steel frame and the reserved steel bracket with horizontal and vertical support plates.

[0014] Step 7: Construction of the cast-in-place concrete section, which includes the following steps.

[0015] Step 1: After the precast concrete beam segment is installed, a hanging platform is set up at the location of the cast-in-place concrete segment to be constructed, serving as an operation and protection platform for the construction of the cast-in-place segment.

[0016] The suspended platform includes platform frame units and connecting frames; there are two platform frame units, respectively arranged on the left and right sides of the rigid steel frame, with the front and rear ends of each platform frame unit extending beyond the ends of the cast-in-place concrete section; each platform frame unit includes a hanging basket and a railing; the railing is a horizontal U-shape, connected to the top of three sides of the hanging basket; an operable platform door is provided between the two side railings, near the side of the precast concrete beam section; two second guardrails are respectively connected to the railings on both sides of the platform door; brackets are provided at the front and rear ends of each platform frame unit; and the brackets are equipped with... Horizontal bracing; the length of the horizontal bracing is adjustable, and the outer end of the horizontal bracing is fixed to the bracket, while the inner end of the horizontal bracing rests on the main structure or a precast concrete beam segment; the connecting frame is located above the rigid steel frame and fixes the two platform frame units together; one end of the connecting frame is supported on the top of the precast concrete beam segment, and the other end of the connecting frame is supported on the top of the support set on the main structure; vertical supports are spaced apart on the connecting frame; the vertical supports are vertically adjustable and connected to the connecting frame to level the suspended platform structure, and the lower end of the vertical supports is supported on the structure below the connecting frame.

[0017] Step 2: Tie the reinforcing bars of the cast-in-place concrete section, and weld the reinforcing bars of the cast-in-place concrete section to the reserved reinforcing bars of the main structure using single-sided welding or double-sided welding.

[0018] Step 3: Use the suspended formwork method to erect the formwork.

[0019] Step 4: Pour and cure the concrete.

[0020] Step 8: Installation of the upper tie rod and the lower support rod: Install the upper tie rod between the upper connecting plate and the embedded component, and support the lower support rod between the lower connecting plate and the embedded component.

[0021] Step Nine: Dismantle the suspended platform, hanging platform, and support frame in sequence: The support frame shall be dismantled after the upper tie rod, lower support rod, and the concrete strength of the cast-in-place concrete section have reached the design requirements. During dismantling, the suspended platform and hanging platform shall be dismantled first using a tower crane, then the connection nodes between the support frame and the main structure shall be dismantled, and finally the tower crane shall lift the support frame and lift it out by adjusting the angle and spatial position of the support frame.

[0022] Preferably, the connecting assembly includes side plates and embedded rods; there are two side plates, which are respectively attached to the inner and outer sides of the main structure's exterior wall; there is a set of embedded rods, which are embedded in the main structure's exterior wall at intervals, and the two ends of the embedded rods are respectively fixedly connected to the side plates on both sides; the longitudinal rods are welded to the side plates on the outer side of the main structure's exterior wall; the pre-embedded assembly includes anchor plates and anchor rods; there are two anchor plates, which are respectively anchored to both sides of the precast concrete beam segment; there is a set of anchor rods, which are spaced apart between the two anchor plates.

[0023] Preferably, at least two of the hanging components are spaced apart at the top of each suspended platform; each hanging component includes a horizontal connecting plate and a vertical connecting plate; the horizontal connecting plate is attached to the exterior wall and fixedly connected to the exterior wall; there are two vertical connecting plates, which are connected to the horizontal connecting plate at intervals along the horizontal direction; a slot is provided on the top surface of the vertical connecting plate; the top rod of the suspended platform is correspondingly engaged in the slot of a set of vertical connecting plates.

[0024] Preferably, the hanging basket includes a base frame, uprights, horizontal connecting rods, and vertical connecting rods; the base frame is a rectangular frame structure; there is a set of uprights connected to the top of the base frame along its four edges; the horizontal connecting rods connect the horizontally adjacent uprights at the front and rear ends of the base frame; the vertical connecting rods connect the vertically adjacent uprights; triangular supports are provided at intervals along the longitudinal direction on the top of the hanging basket; the left and right sides of the connecting frame are fixedly connected to the corresponding triangular supports.

[0025] Preferably, the bracket includes a support plate and a reaction plate; the support plate is horizontally fixed on the front and rear end faces of the platform frame unit, near the inner side of the platform frame unit; the reaction plate is fixedly connected to the top of the support plate, near the middle position; the horizontal support is a horizontally set jack, and the fixed end of the jack is fixedly connected to the inner side of the reaction plate, while the free end of the jack rests on the main structure or a precast concrete beam segment; a stiffening plate is provided between the outer side of the reaction plate and the support plate.

[0026] Preferably, the connecting frame is a rectangular grid structure, with a platform plate laid on the bottom frame; the vertical support is arranged along the front and rear sides and the horizontal axis of the connecting frame; a threaded sleeve is provided on the connecting frame at the position corresponding to the vertical support; the outer surface of the vertical support is provided with an external thread and is threadedly connected to the threaded sleeve; a horizontal support plate is provided at the bottom of the vertical support.

[0027] Preferably, in step six, when hoisting the precast concrete beam segment, the precast concrete beam segment is hoisted using a three-point method, connecting the sling at the middle hoisting point to a hand-operated hoist; first, hoist the precast concrete beam segment 10-20cm off the ground, use the hand-operated hoist to level the precast concrete beam segment, keep it stationary for at least 5 minutes and observe the hoisting point and the precast concrete beam segment. If the hoisting point is firm and the precast concrete beam segment is in a stable state, then hoisting can continue.

[0028] Preferably, in step nine, the specific process of dismantling the support frame is as follows:

[0029] Step 1: After the hoisting slings on the support frame are connected, remove the suspended basket in the installation area and lower the support frame vertically by tower crane 1.5 to 2 meters; construction workers adjust the direction of the support frame in the opening area with the help of guy ropes or steel pipes.

[0030] Step 2: After the direction of the support frame is adjusted, use a tower crane to vertically raise the support frame to a position 200mm~250mm above the cantilevered curved beam;

[0031] Step 3: After the bottom of the support frame extends beyond the upper surface of the cantilevered curved beam, the support frame is moved horizontally out of the installation area of ​​the cantilevered curved beam and down to the ground using the on-site tower crane. At this point, the dismantling of the support frame is complete.

[0032] Compared with the prior art, the present invention has the following features and beneficial effects.

[0033] 1. The construction method of this invention optimizes the cast-in-place concrete cantilevered arc beam into a "precast concrete beam segment + cast-in-place concrete segment", reducing high-altitude operations such as rebar tying, formwork erection, and concrete pouring, and greatly reducing the safety hazards of high-altitude operations. The precast concrete beam segment is prefabricated on the construction site and then hoisted as a whole, reducing the need for a support system, shortening the construction period, and saving materials and costs. At the same time, after the precast concrete beam segment is hoisted, one end of the precast concrete beam segment is connected to the steel column of the main structure through a stiffening steel frame, and the other side of the precast concrete beam segment is temporarily supported by a support frame, thereby effectively ensuring the stability and safety of the precast concrete beam segment before installation of the lower strut and upper tie rod.

[0034] 2. The suspended platform structure of this invention is suspended at the location of the cast-in-place rigid connection section to be constructed, reducing the need for high-altitude operations such as rebar tying, formwork erection, and concrete pouring, greatly reducing safety hazards associated with high-altitude work. It adopts a simple and time-saving construction method while ensuring safety and quality. One end of the suspended platform structure is supported on the installed precast beam segment, and the other end is supported on the pre-set supports of the main structure, reducing the need for a support system, shortening the construction period, and saving materials and costs. Furthermore, the suspended platform structure is equipped with adjustable vertical supports, which can adjust the balance of the suspended platform structure, ensuring stable construction for workers in the later stages.

[0035] 3. The present invention provides horizontal supports at both ends of the platform frame unit. During installation, the horizontal supports are placed on the main structure or the precast beam segment that has been installed, which avoids the platform frame unit from shaking and becoming unstable during construction and ensures the safety of construction personnel.

[0036] 4. The present invention sets up first guardrails on both sides of the horizontal and diagonal bars of the support frame to form a passage, and sets up second guardrails on both sides of the top of the precast concrete beam segment. By using the existing structure as a construction passage or platform, the construction of the support system is reduced, and materials and costs are saved. Attached Figure Description

[0037] The present invention will now be described in further detail with reference to the accompanying drawings.

[0038] Figure 1 is a schematic diagram of the high-rise, high-altitude, large-span cantilevered concrete structure of the present invention.

[0039] Figure 2 is a schematic diagram of the connection between the cantilevered arc beam and the main structure in this invention.

[0040] Figure 3 is a schematic diagram of the cantilevered curved beam in this invention.

[0041] Figure 4 is a schematic diagram of the connection between the rigid steel frame and the steel bracket in this invention.

[0042] Figure 5 is a diagram showing the arrangement of the support frame and the suspended basket in this invention.

[0043] Figure 6 is a schematic diagram of the support frame in this invention.

[0044] Figure 7 is a schematic diagram of the connection node structure between the cantilevered arc beam and the support frame in this invention.

[0045] Figure 8 is a schematic diagram of the structure of the hanging component in this invention.

[0046] Figure 9 is a schematic diagram of the connection structure between the hanging platform and the precast concrete beam segment and the support plate on the main structure in this invention.

[0047] Figure 10 is a layout diagram of the suspended platform in this invention.

[0048] Figure 11 is a schematic diagram of the structure of the suspended platform in this invention.

[0049] Figure 12 is a schematic diagram of the horizontal brace in this invention.

[0050] Reference numerals in the attached drawings: 1 – Cantilevered curved beam; 1.1 – Precast concrete beam segment; 1.2 – Cast-in-place concrete segment; 1.2.1 – Reinforcing steel frame; 1.2.2 – Cast-in-place concrete layer; 2 – Upper tie rod; 3 – Lower strut; 4 – Horizontal support plate; 5 – Main structure; 6 – Steel column; 7 – Steel bracket; 8 – Embedded component; 8.1 – Anchor plate; 8.2 – Anchor rod; 9 – Upper connecting plate; 10 – Fixing plate; 11 – Support frame; 11.1 – Vertical support unit; 11.1.1 – Longitudinal bar; 11.1.2 – Vertical bar; 11.1.3 – Vertical diagonal bar; 11.2 – Horizontal support unit; 11.2.1 – Horizontal bar; 11.2.2 – Horizontal diagonal bar; 12 – Suspended basket; 13 – Hanging component; 13.1 – Horizontal connecting plate 13.2 - Longitudinal connecting plate; 14 - Connecting assembly; 14.1 - Side plate; 14.2 - Embedded rod; 15 - Lifting ring; 16 - Lateral limiting plate; 17 - First guardrail; 18 - Platform frame unit; 18.1 - Hanging basket; 18.1.1 - Base frame; 18.1.2 - Upright; 18.1.3 - Horizontal connecting rod; 18.1.4 - Longitudinal connecting rod; 18.1.5 - Platform plate; 18.2 - Fence; 19 - Connecting frame; 20 - Second guardrail; 21 - Platform gate; 22 - Bracket; 22.1 - Support plate; 22.2 - Reaction plate; 22.3 - Stiffening plate; 23 - Horizontal brace; 24 - Vertical support; 25 - Slot; 26 - Triangular support frame; 27 - Threaded sleeve; 28 - Lower connecting plate. Detailed Implementation

[0051] As shown in Figure 1-12, this construction method for a high-rise, high-altitude, large-span cantilevered concrete structure includes a cantilevered curved beam 1, an upper tie rod 2, and a lower support rod 3. The cantilevered curved beam 1 is curved, with one end connected to the main structure 5 and the other end separated from the main structure 5. The cantilevered curved beam 1 includes a precast concrete beam segment 1.1 and a cast-in-place concrete segment 1.2. The precast concrete beam segment 1.1 is connected to the main structure 5 via the upper tie rod 2 and the lower support rod 3, and both ends of the precast concrete beam segment 1.1 are separated from the main structure 5. The cast-in-place concrete segment 1.2 connects one end of the precast concrete beam segment 1.1 to the main structure 5, and includes a rigid steel frame 1.2.1 and a cast-in-place concrete layer 1.2.2. The rigid steel frame 1.2.1 is installed within the cast-in-place concrete layer 1.2.2, and... One end of the rigid steel frame 1.2.1 is fixedly connected to the main structure 5; a steel column 6 is provided in the main structure 5 at the connection position corresponding to the cantilevered arc beam 1; a steel bracket 7 is provided on the steel column 6; the rigid steel frame 1.2.1 is welded to the steel bracket 7; the other end of the rigid steel frame 1.2.1 extends beyond the cast-in-place concrete layer 1.2.2 and into the precast concrete beam segment 1.1; a pre-embedded component 8 is pre-embedded on the side of the precast concrete beam segment 1.1 facing the main structure 5, near the end position; an upper connecting plate 9 is provided on the outer wall of the main structure 5 above the cantilevered arc beam 1, and a lower connecting plate 28 is provided on the outer wall of the main structure 5 below the cantilevered arc beam 1; an upper tie rod 2 is pulled between the upper connecting plate 9 and the pre-embedded component 8, and a lower support rod 3 is supported between the lower connecting plate 28 and the pre-embedded component 8; a fixing plate 10 is provided on the pre-embedded component 8, and longitudinal strip holes are opened on the fixing plate 10.

[0052] The construction method includes the following steps.

[0053] Step 1: Structural optimization and construction drawing design of the cantilevered concrete structure: Calculate the specifications of the pre-embedded steel columns 6 and the extended steel brackets 7 in the main structure 5, the internal stiffening steel ribs 1.2.1 and anchorage length of the cast-in-place concrete section 1.2, based on the overall structural stress requirements. In addition, determine the scope of the precast concrete beam section 1.1 and the cast-in-place concrete section 1.2 based on the tower crane lifting performance analysis, to ensure that the structural stress requirements and on-site construction conditions are met.

[0054] Step two, detailed design of the support measures, which include a support frame 11 and a suspended platform 12; to ensure the stable and safe installation of the precast concrete beam segment 1.1, the support frame 11 is used as the support and working platform for the precast concrete beam segment 1.1; the support frame 11 adopts a triangular frame structure, with bidirectional diagonal bracing installed in both the vertical and horizontal directions; the support frame 11 includes a vertical support unit 11.1 and a horizontal support unit 11.2; the vertical support unit 11.1 includes... The structure comprises a longitudinal rod 11.1.1, a vertical rod 11.1.2, and a vertical diagonal rod 11.1.3; the vertical diagonal rod 11.1.3 is obliquely positioned above the top of the longitudinal rod 11.1.1, with its lower end connected to the top of the longitudinal rod 11.1.1 near its outer end, and its upper end vertically aligned with the inner end of the longitudinal rod 11.1.1; a [missing information - likely a design element] is provided on the top of the longitudinal rod 11.1.1, on the outer side of the vertical diagonal rod 11.1.3. A lateral limiting plate 16; longitudinal strip holes are spaced apart on the surface of the lateral limiting plate 16; the vertical rod 11.1.2 is supported between the vertical rod 11.1.1 and the vertical diagonal rod 11.1.3, near the inner end of the vertical rod 11.1.1 and the vertical diagonal rod 11.1.3, and the vertical rod 11.1.2, the vertical rod 11.1.1, and the vertical diagonal rod 11.1.3 form a right-angled triangle; the horizontal support unit 11.2 is arranged on one side of the vertical support unit 11.1, including a horizontal... The structure includes a rod 11.2.1 and a horizontal diagonal rod 11.2.2; the horizontal rod 11.2.1 is connected to the lower part of the vertical rod 11.1.1; the horizontal diagonal rod 11.2.2 is connected to the end of the horizontal rod 11.2.1, and the outer end of the horizontal diagonal rod 11.2.2 is connected to the lower part of the vertical diagonal rod 11.1.3; there is one set of suspended baskets 12, which are installed near the node position between the support frame 11 and the outer wall of the main structure 5, and the suspended baskets 12 are connected to the outer wall of the main structure 5 through the hanging assembly 13.

[0055] Step 3: The main structure is constructed first. The steel columns 6, steel brackets 7, and connecting components 14 required for the construction of the cantilevered curved beam 1 are constructed together with the main structure 5 and are pre-embedded. During the pre-embedding, it is ensured that the positioning, size, flatness, and verticality of the pre-embedded parts meet the design requirements.

[0056] Step 4, On-site Precasting of Precast Concrete Beam Segment 1.1: Due to the excessive length of the precast concrete beam segment 1.1, which does not meet road transportation requirements, and considering cost savings and construction time, the precast concrete beam segment 1.1 will be constructed on-site. During the fabrication of the precast concrete beam segment 1.1, one end of the reinforcing steel frame 1.2.1 will be pre-embedded in the precast concrete beam segment 1.1. Within the coverage area of ​​the on-site tower crane, short arc-shaped supports using steel pipes or disc-lock scaffolds will be used. The aluminum formwork bottom formwork will be laid on the support frame. After the reinforcement is tied, the steel structure embedded parts and steel box girder will be pre-embedded. After the concealed acceptance, the aluminum formwork will be installed. After the aluminum formwork is reinforced, the dimensions and reinforcement measures of the aluminum formwork will be inspected. After passing the inspection, early-strength concrete will be poured, and the same conditions test blocks and standard curing test blocks will be prepared.

[0057] Step 5, Fabrication and Installation of Support Frame 11: The support frame 11 is assembled on the construction site. First guardrails 17 are set on both sides of the horizontal diagonal bar 11.2.2 and both sides of the horizontal bar 11.2.1 to form passages. Lifting rings 15 are set on the upper surface of the vertical diagonal bar 11.1.3 near the upper end, the top of the longitudinal bar 11.1.1 near the outer end, and the top of the horizontal diagonal bar 11.2.2 near the inner end. The lifting rings 15 are fixed to the support frame by welding with 20mm steel plates, and the weld is a double-sided fillet weld. After the support frame 11 and the first guardrails 17 are welded into a whole, they are installed in place by three-point hoisting using a tower crane on site. The upper ends of the longitudinal bar 11.1.1, the vertical diagonal bar 11.1.3, and the inner end of the horizontal diagonal bar 11.2.2 are connected to the outer wall of the main structure 5 through connecting components 14. The passage at the top of the horizontal diagonal bar 11.2.2 is connected to the reserved opening on the floor.

[0058] Step Six: Lifting of Precast Concrete Beam Segment 1.1: Before lifting, set up second guardrails 20 on both sides of the top surface of the precast concrete beam segment 1.1. Then, lift the precast concrete beam segment 1.1 and place it on the support frame 11. During the installation of the precast concrete beam segment 1.1, use a tower crane to lift it slowly and use guy ropes and other measures to assist in positioning. The far end of the curved beam rests on the support frame and is limited by the lateral limiting plate 16. Make the lateral limiting plate 16 contact the surface of the fixing plate 10, and connect the lateral limiting plate 16 to the fixing plate 10 by inserting bolts into the longitudinal strip holes. At the same time, temporarily fix the stiffening steel frame 1.2.1 and the reserved steel bracket 7 with horizontal and vertical support plates.

[0059] Step 7: Construction of cast-in-place concrete section 1.2, which includes the following steps.

[0060] Step 1: After the precast concrete beam segment 1.1 is installed, a hanging platform is installed at the location of the cast-in-place concrete segment 1.2 to be constructed, which serves as the working and protective platform for the construction of the cast-in-place segment.

[0061] The suspended platform includes a platform frame unit 18 and a connecting frame 19; there are two platform frame units 18, respectively arranged on the left and right sides of the rigid steel frame 1.2.1, and the front and rear ends of the platform frame unit 18 extend beyond the ends of the cast-in-place concrete section 1.2; the platform frame unit 18 includes a hanging basket 18.1 and a railing 18.2; the railing 18.2 is a horizontal U-shape, connected to the top of three sides of the hanging basket 18.1; an openable platform door 21 is provided between the two railings 18.2, near the side of the precast concrete beam section 1.1; two second guardrails 20 are respectively connected to the railings 18.2 on both sides of the platform door 21; brackets 22 are respectively provided at the front and rear ends of the platform frame unit 18; the brackets 22 are respectively provided at the front and rear ends of the platform frame unit 18. A horizontal brace 23 is installed on the frame 22; the length of the horizontal brace 23 is adjustable, and the outer end of the horizontal brace 23 is fixed on the bracket 22, while the inner end of the horizontal brace 23 rests on the main structure 5 or the precast concrete beam segment 1.1; the connecting frame 19 is located above the rigid steel frame 1.2.1 and fixes the two platform frame units 18 together; one end of the connecting frame 19 is supported on the top of the precast concrete beam segment 1.1, and the other end of the connecting frame 19 is supported on the top of the support set on the main structure 5; vertical supports 24 are arranged at intervals on the connecting frame 19; the vertical supports 24 are vertically adjustable and connected to the connecting frame 19 to level the suspended platform structure, and the lower end of the vertical supports 24 is supported on the structure below the connecting frame 19.

[0062] Step 2: Tie the reinforcing bars of the cast-in-place concrete section 1.2, and weld the reinforcing bars of the cast-in-place concrete section 1.2 to the reserved reinforcing bars of the main structure using single-sided welding or double-sided welding; the main reinforcing bars of the cast-in-place concrete section 1.2 are the extended parts of the main reinforcing bars in the precast concrete beam section 1.1.

[0063] Step 3: Use the suspended formwork method to erect the formwork.

[0064] Step 4: Pour and cure the concrete; when pouring the concrete, increase the grade by one and add three days of early strength.

[0065] Step 8: Installation of Upper Tie Rod 2 and Lower Support Rod 3: Install the upper tie rod 2 between the upper connecting plate 9 and the embedded component 8, and simultaneously support the lower support rod 3 between the lower connecting plate 28 and the embedded component 8; install the upper tie rod 2 and lower support rod 3 into position using a tower crane on site. Before hoisting the upper tie rod 2 and lower support rod 3, the upper connecting plate 9, lower connecting plate 28, and pin shaft must be installed on the ground and fireproof coating must be applied. Install limit brackets on the tie rod embedded parts; the upper tie rod 2 and lower support rod 3 are hoisted using a two-point hoisting method, with the hoisting point set at the embedded component 8. One end of the hoisting point is equipped with a 2-ton hand-operated hoist connected to a wire rope for on-site installation and adjustment; construction personnel use the passage or suspended platform 12 to reach the node connection area to perform relevant correction and welding operations. The weld grade of the upper tie rod 2 and lower support rod 3 to the embedded part is a first-class full penetration weld.

[0066] Step Nine: Dismantle the suspended platform 12, the suspended platform and the support frame 11 in sequence: The support frame 11 will be dismantled after the upper tie rod 2, the lower support rod 3 and the concrete strength of the cast-in-place concrete section 1.2 have reached the design requirements. During dismantling, the suspended platform 12 and the suspended platform will be dismantled first using a tower crane. Then, the connection nodes between the support frame 11 and the main structure will be dismantled in sequence. Finally, the tower crane will lift the support frame 11 and lift it out by adjusting the angle and spatial position of the support frame 11 to avoid collision with other structures.

[0067] In this embodiment, the connecting component 14 includes side plates 14.1 and embedded rods 14.2; there are two side plates 14.1, which are respectively attached to the inner and outer sides of the outer wall of the main structure 5; there is a set of embedded rods 14.2, which are embedded in the outer wall of the main structure 5 at intervals, and the two ends of the embedded rods 14.2 are respectively fixedly connected to the side plates 14.1 on both sides; the longitudinal rod 11.1.1 is welded to the side plates 14.1 on the outer side of the outer wall of the main structure 5; the pre-embedded component 8 includes anchor plates 8.1 and anchor rods 8.2; there are two anchor plates 8.1, which are respectively anchored to both sides of the precast concrete beam segment 1.1; there is a set of anchor rods 8.2, which are pulled between the two anchor plates 8.1 at intervals.

[0068] In this embodiment, at least two of the hanging components 13 are spaced apart at the top of each suspended platform 12; the hanging components 13 include a horizontal connecting plate 13.1 and a vertical connecting plate 13.2; the horizontal connecting plate 13.1 is attached to the exterior wall and fixedly connected to the exterior wall; there are two vertical connecting plates 13.2, which are connected to the horizontal connecting plate 13.1 at intervals along the horizontal direction; anchoring steel bars are provided on the back of the horizontal connecting plate 13.1; a slot 25 is provided on the top of the surface of the vertical connecting plate 13.2; the top rod of the suspended platform 12 is correspondingly locked in the slot 25 of a set of vertical connecting plates 13.2.

[0069] In this embodiment, the hanging basket 18.1 includes a base frame 18.1.1, uprights 18.1.2, transverse connecting rods 18.1.3, and longitudinal connecting rods 18.1.4. The base frame 18.1.1 is a rectangular frame structure. There is a set of uprights 18.1.2, which are connected to the top of the base frame 18.1.1 along the four edges of the base frame 18.1.1. The transverse connecting rods 18.1.3 are connected between the transversely adjacent uprights 18.1.2 at the front and rear ends of the base frame 18.1.1. The longitudinal connecting rods 18.1.4 are connected between the longitudinally adjacent uprights 18.1.2. Triangular supports 26 are arranged at intervals along the longitudinal direction on the top of the hanging basket 18.1. The left and right sides of the connecting frame 19 are respectively fixedly connected to the corresponding triangular supports 26.

[0070] In this embodiment, the bracket 22 includes a support plate 22.1 and a reaction plate 22.2; the support plate 22.1 is horizontally fixed on the front and rear end faces of the platform frame unit 18, near the inner side of the platform frame unit 18; the reaction plate 22.2 is fixedly connected to the top of the support plate 22.1, near the middle position; the horizontal support 23 is a horizontally set jack, and the fixed end of the jack is fixedly connected to the inner side of the reaction plate 22.2, and the free end of the jack rests on the main structure 5 or the precast concrete beam segment 1.1; a stiffening plate 22.3 is provided between the outer side of the reaction plate 22.2 and the support plate 22.1.

[0071] In this embodiment, the connecting frame 19 is a rectangular frame structure, and a platform plate 18.1.5 is laid on the bottom frame 18.1.1; the vertical support 24 is arranged along the front and rear sides and the horizontal axis of the connecting frame 19; a threaded sleeve 27 is provided on the connecting frame 19 at the position corresponding to the vertical support 24; the outer surface of the vertical support 24 is provided with external threads and is threadedly connected to the threaded sleeve 27; a horizontal support plate 4 is provided at the bottom of the vertical support 24.

[0072] In this embodiment, when hoisting the precast concrete beam segment 1.1 in step five, the precast concrete beam segment 1.1 is hoisted using a three-point method. The sling at the middle hoisting point is connected to a hand-operated hoist to level the precast concrete beam segment 1.1. First, the precast concrete beam segment 1.1 is hoisted 10-20cm off the ground, and the precast concrete beam segment 1.1 is leveled using a hand-operated hoist. The hoisting is allowed to stand still for at least 5 minutes, and the hoisting points and the precast concrete beam segment 1.1 are observed. If the hoisting points are secure and the precast concrete beam segment 1.1 is in a stable state, the hoisting can continue.

[0073] In this embodiment, the specific process of removing the support frame 11 in step eight is as follows.

[0074] Step 1: After the hoisting slings on the support frame 11 are connected, remove the suspended basket 12 in the installation area and lower the support frame 11 vertically by tower crane 1.5 to 2 meters; construction workers adjust the direction of the support frame 11 in the opening area with the help of guy ropes or steel pipes.

[0075] Step 2: After the direction of the support frame 11 is adjusted, the support frame 11 is vertically raised to a position 200mm~250mm above the cantilevered curved beam 1 using a tower crane.

[0076] Step 3: After the bottom of the support frame extends beyond the upper surface of the cantilevered curved beam 1, the support frame 11 is moved horizontally from below the installation area of ​​the cantilevered curved beam 1 to the ground using the on-site tower crane. At this point, the support frame 11 has been completely dismantled.

[0077] In this embodiment, the reinforcing bars of the cast-in-place concrete section 1.2 are formed by the spur bars at the ends of the precast concrete beam section 1.1.

[0078] In this embodiment, the side of the platform frame unit 18 closest to the rigid steel rib 1.2.1 is the inner side, and the side of the platform frame unit 18 furthest from the rigid steel rib 1.2.1 is the outer side.

[0079] In this embodiment, the support provided on the main structure 5 is a support plate that is pre-installed on the main structure 5.

[0080] In this embodiment, reinforcing bars of cast-in-place concrete sections 1.2 are arranged at intervals around the rigid steel frame 1.2.1. One end of the reinforcing bars of the cast-in-place concrete sections 1.2 is connected to the reinforcing bars reserved on the main structure 5, and the other end of the reinforcing bars of the cast-in-place concrete sections 1.2 is connected to the reinforcing bars of the precast concrete beam sections 1.1. When a vertical support 24 is provided on the rigid steel frame 1.2.1, the lower end of the vertical support 24 is supported on the top of the rigid steel frame 1.2.1. When the concrete on the top of the rigid steel frame 1.2.1 is poured, the vertical support 24 is screwed upward so that the lower end of the vertical support 24 is higher than the top surface of the cast-in-place concrete section 1.2. The vertical support 24 is a screw rod, a threaded reinforcing bar, or a threaded steel pipe.

[0081] The above embodiments are not exhaustive examples of specific implementation methods, and other embodiments are also possible. The purpose of the above embodiments is to illustrate the present invention, rather than to limit the scope of protection of the present invention. All applications derived from simple variations of the present invention fall within the scope of protection of the present invention.

Claims

1. A construction method for a high-rise, large-span cantilevered concrete structure, characterized in that, The high-rise, high-altitude, large-span cantilevered concrete structure includes a cantilevered arc beam (1), an upper tie rod (2), and a lower support rod (3). The cantilevered arc beam (1) is arc-shaped, with one end connected to the main structure (5) and the other end of the cantilevered arc beam (1) having a gap between it and the main structure (5). The cantilevered arc beam (1) includes a precast concrete beam segment (1.1) and a cast-in-place concrete segment (1.2). The precast concrete beam segment (1.1) is connected to the main structure (5) via the upper tie rod (2) and the lower support rod (3), and a gap is left between both ends of the precast concrete beam segment (1.1) and the main structure (5). The cast-in-place concrete segment (1.2) is connected to the precast concrete beam. One end of segment (1.1) is connected to the main structure (5). The cast-in-place concrete segment (1.2) includes a rigid steel frame (1.2.1) and a cast-in-place concrete layer (1.2.2). The rigid steel frame (1.2.1) is installed inside the cast-in-place concrete layer (1.2.2), and one end of the rigid steel frame (1.2.1) is fixedly connected to the main structure (5). A steel column (6) is provided in the main structure (5) at the connection position corresponding to the cantilevered curved beam (1). A steel bracket (7) is provided on the steel column (6). The rigid steel frame (1.2.1) is welded to the steel bracket (7). The other end of the rigid steel frame (1.2.1) extends beyond the cast-in-place concrete layer (1.2.2) and protrudes. An embedded component (8) is embedded in a precast concrete beam segment (1.1); an embedded component (8) is embedded on the side of the precast concrete beam segment (1.1) facing the main structure (5) near the end; an upper connecting plate (9) is provided on the outer wall of the main structure (5) above the cantilevered arc beam (1), and a lower connecting plate (28) is provided on the outer wall of the main structure (5) below the cantilevered arc beam (1); the upper tie rod (2) is pulled between the upper connecting plate (9) and the embedded component (8), and the lower support rod (3) is supported between the lower connecting plate (28) and the embedded component (8); a fixing plate (10) is provided on the embedded component (8), and longitudinal strip holes are opened on the fixing plate (10); the construction method includes The steps are as follows: Step 1, structural optimization and construction drawing design of cantilever concrete structure: Calculate the specifications of the steel column (6) and the extended steel bracket (7) embedded in the main structure (5) according to the overall stress requirements of the structure, the internal stiffening steel (1.2.1) and anchorage length of the cast-in-place concrete section (1.2), and determine the scope division of the precast concrete beam section (1.1) and the cast-in-place concrete section (1.2) to ensure that the structural stress requirements and on-site construction conditions are met; Step 2, detailed design of support measures, which include support frame (11) and hanging basket (12); In order to ensure the stable and safe installation of the precast concrete beam section (1.1), support frame (11) is used as the precast concrete beam section (1.2).1) Support and working platform; The support frame (11) adopts a triangular frame structure, with bidirectional diagonal bracing on both the vertical and horizontal directions; The support frame (11) includes a vertical support unit (11.1) and a horizontal support unit (11.2); The vertical support unit (11.1) includes a longitudinal rod (11.1.1), a vertical rod (11.1.2) and a vertical diagonal rod (11.1.3); The vertical diagonal rod (11.1.3) is inclinedly arranged above the top of the longitudinal rod (11.1.1), and the lower end of the vertical diagonal rod (11.1.3) is connected to the top of the longitudinal rod (11.1.1) near the outer end, and the upper end of the vertical diagonal rod (11.1.3) is vertically parallel to the inner end of the longitudinal rod (11.1.1). The vertical rod (11.1.1) is topped with a lateral limiting plate (16) on the outer side of the vertical diagonal rod (11.1.3); the lateral limiting plate (16) has longitudinal strip holes spaced apart on its surface; the vertical rod (11.1.2) is supported between the vertical rod (11.1.1) and the vertical diagonal rod (11.1.3), near the inner end of the vertical rod (11.1.1) and the vertical diagonal rod (11.1.3), and the vertical rod (11.1.2) forms a right triangle with the vertical rod (11.1.1) and the vertical diagonal rod (11.1.3); the horizontal support unit (11.2) is located on one side of the vertical support unit (11.1), and includes a horizontal rod (11.2.1) and a horizontal diagonal rod (11.2.1). 2.2); The horizontal bar (11.2.1) is connected to the lower part of the vertical bar (11.1.1); The horizontal diagonal bar (11.2.2) is connected to the end of the horizontal bar (11.2.1), and the outer end of the horizontal diagonal bar (11.2.2) is connected to the lower part of the vertical diagonal bar (11.1.3); There is one set of suspended baskets (12), which are installed near the node position between the support frame (11) and the outer wall of the main structure (5), and the suspended baskets (12) are connected to the outer wall of the main structure (5) through the hanging assembly (13); Step 3, the main structure is constructed first, and the steel column (6), steel bracket (7) and connecting assembly (14) required for the construction of the cantilevered arc beam (1) are constructed together with the main structure (5) and pre-embedded. When pre-embedding, ensure that the positioning, size, flatness and verticality of the pre-embedded parts meet the design requirements; Step 4, precast concrete beam segment (1.1) on site: when making precast concrete beam segment (1.1), one end of the stiffening steel frame (1.2.1) is pre-embedded in the precast concrete beam segment (1.1); Step 5, fabrication and installation of support frame (11): the support frame (11) is assembled on the construction site, and the first guardrail (17) is set on both sides of the horizontal diagonal bar (11.2.2) and both sides of the horizontal bar (11.2.1) to form a passage; on the upper surface of the vertical diagonal bar (11.1.3), near the upper end, at the top of the longitudinal bar (11.1.1), near the outer end, and on the horizontal diagonal bar (11.2.2).2) Lifting rings (15) are set at the top and near the inner end of the support frame (11) and the first guardrail (17) are welded together and then installed in place by a three-point hoisting method using a tower crane on site. The upper ends of the longitudinal rod (11.1.1), the vertical diagonal rod (11.1.3) and the inner end of the horizontal diagonal rod (11.2.2) are connected to the outer wall of the main structure (5) through the connecting component (14); the passage at the top of the horizontal diagonal rod (11.2.2) is connected to the reserved opening on the floor; Step 6: hoisting of the precast concrete beam segment (1.1): Before hoisting, a second guardrail (20) is set on both sides of the top surface of the precast concrete beam segment (1.1). Then, the precast concrete beam segment (1.1) is lifted and placed on the support frame (11); the lateral limiting plate (16) is brought into contact with the fixed plate (10), and the bolts are inserted into the longitudinal strip holes to connect the lateral limiting plate (16) and the fixed plate (10); at the same time, the stiffening steel frame (1.2.1) and the reserved steel bracket (7) are temporarily fixed by horizontal and vertical support plates; Step 7: Construction of the cast-in-place concrete segment (1.2) includes the following steps: Step 1, after the precast concrete beam segment (1.1) is installed, a hanging platform is set up at the location of the cast-in-place concrete segment (1.2) to be constructed, as the operation and protection platform for the construction of the cast-in-place segment; the hanging platform is set up by the precast concrete beam segment (1.1) to be constructed. The platform includes a platform frame unit (18) and a connecting frame (19); there are two platform frame units (18), which are respectively arranged on the left and right sides of the rigid steel frame (1.2.1), and the front and rear ends of the platform frame unit (18) extend beyond the two ends of the cast-in-place concrete section (1.2); the platform frame unit (18) includes a hanging basket (18.1) and a fence (18.2); the fence (18.2) is in the shape of a horizontal U and is connected to the top of the three sides of the hanging basket (18.1); between the two fences (18.2) on the side near the precast concrete beam section (1.1), there is an openable platform door (21); two second guardrails (20) Connected to the railings (18.2) on both sides of the platform gate (21); brackets (22) are respectively provided at the front and rear ends of the platform frame unit (18); horizontal supports (23) are installed on the brackets (22); the length of the horizontal supports (23) is adjustable, and the outer end of the horizontal supports (23) is fixed on the brackets (22), and the inner end of the horizontal supports (23) rests on the main structure (5) or the precast concrete beam segment (1.1); the connecting frame (19) is located above the rigid steel frame (1.2.1) and fixes the two platform frame units (18); one end of the connecting frame (19) is supported on the precast concrete beam segment (1).1) At the top, the other end of the connecting frame (19) is supported on the support top set on the main structure (5); vertical supports (24) are set at intervals on the connecting frame (19); the vertical supports (24) are vertically adjustable and connected to the connecting frame (19) to level the suspended platform structure, and the lower end of the vertical supports (24) is supported on the structure below the connecting frame (19); Step 2, tie the reinforcing bars of the cast-in-place concrete section (1.2), and weld the reinforcing bars of the cast-in-place concrete section (1.2) to the reserved reinforcing bars of the main structure by single-sided welding or double-sided welding; Step 3, use the formwork erection method; Step 4, pour and cure concrete; Step 8: upper tie rod (2) and lower support Installation of rod (3): Install the upper tie rod (2) between the upper connecting plate (9) and the embedded component (8), and support the lower support rod (3) between the lower connecting plate (28) and the embedded component (8); Step 9: Sequentially dismantle the suspended basket (12), the suspended platform and the support frame (11): The support frame (11) is dismantled after the concrete strength of the upper tie rod (2), the lower support rod (3) and the cast-in-place concrete section (1.2) reaches the design requirements. During dismantling, the suspended basket (12) and the suspended platform are dismantled first using a tower crane, then the connection node between the support frame (11) and the main structure is dismantled, and finally the tower crane lifts the support frame (11) and lifts it out by adjusting the angle and spatial position of the support frame (11).

2. The construction method for high-rise, large-span cantilevered concrete structures according to claim 1, characterized in that: The connecting component (14) includes a side plate (14.1) and an embedded rod (14.2); there are two side plates (14.1), which are respectively attached to the inner and outer sides of the outer wall of the main structure (5); there is one set of embedded rods (14.2), which are embedded in the outer wall of the main structure (5) at intervals, and the two ends of the embedded rods (14.2) are respectively fixedly connected to the side plates (14.1) on both sides; the longitudinal rod (11.1.1) is welded to the side plate (14.1) on the outer side of the outer wall of the main structure (5); the pre-embedded component (8) includes an anchor plate (8.1) and an anchor rod (8.2); there are two anchor plates (8.1), which are respectively anchored to both sides of the precast concrete beam segment (1.1); there is one set of anchor rods (8.2), which are pulled between the two anchor plates (8.1) at intervals.

3. The construction method for high-rise, high-altitude, large-span cantilevered concrete structures according to claim 1, characterized in that: At least two of the hanging components (13) are spaced apart at the top of each suspended platform (12); the hanging components (13) include a horizontal connecting plate (13.1) and a vertical connecting plate (13.2); the horizontal connecting plate (13.1) is attached to the exterior wall and fixedly connected to the exterior wall; there are two vertical connecting plates (13.2) connected horizontally at intervals to the horizontal connecting plate (13.1); a slot (25) is provided on the top of the surface of the vertical connecting plate (13.2); the top rod of the suspended platform (12) is correspondingly locked in the slot (25) of a set of vertical connecting plates (13.2).

4. The construction method for high-rise, large-span cantilevered concrete structures according to claim 1, characterized in that: The hanging basket (18.1) includes a base frame (18.1.1), uprights (18.1.2), horizontal connecting rods (18.1.3), and vertical connecting rods (18.1.4). The base frame (18.1.1) is a rectangular frame structure. There is a set of uprights (18.1.2) that are connected to the top of the base frame (18.1.1) along the four edges of the base frame (18.1.1). The horizontal connecting rods (18.1.3) are connected between the horizontally adjacent uprights (18.1.2) at the front and rear ends of the base frame (18.1.1). The vertical connecting rods (18.1.4) are connected between the vertically adjacent uprights (18.1.2). Triangular supports (26) are provided at intervals along the longitudinal direction on the top of the hanging basket (18.1). The left and right sides of the connecting frame (19) are fixedly connected to the corresponding triangular supports (26).

5. The construction method for high-rise, high-altitude, large-span cantilevered concrete structures according to claim 1, characterized in that: The bracket (22) includes a support plate (22.1) and a reaction plate (22.2); the support plate (22.1) is horizontally fixed on the front and rear end faces of the platform frame unit (18), near the inner side of the platform frame unit (18); the reaction plate (22.2) is fixedly connected to the top of the support plate (22.1), near the middle position; the horizontal support (23) is a horizontally set jack, and the fixed end of the jack is fixedly connected to the inner side of the reaction plate (22.2), and the free end of the jack rests on the main structure (5) or the precast concrete beam segment (1.1); a stiffening plate (22.3) is provided between the outer side of the reaction plate (22.2) and the support plate (22.1).

6. The construction method for high-rise, large-span cantilevered concrete structures according to claim 1, characterized in that: The connecting frame (19) is a rectangular frame structure, and a platform plate (18.1.5) is laid on the bottom frame (18.1.1); the vertical support (24) is arranged along the front and rear sides and the horizontal axis of the connecting frame (19); a threaded sleeve (27) is provided on the connecting frame (19) at the position corresponding to the vertical support (24); the outer surface of the vertical support (24) is provided with an external thread, and is threadedly connected to the threaded sleeve (27); a horizontal support plate (4) is provided at the bottom of the vertical support (24).

7. The construction method for high-rise, high-altitude, large-span cantilevered concrete structures according to claim 1, characterized in that: In step six, when hoisting the precast concrete beam segment (1.1), the precast concrete beam segment (1.1) is hoisted using a three-point method. The sling on the middle hoisting point is connected to the hand-operated hoist. First, the precast concrete beam segment (1.1) is hoisted 10-20cm off the ground. The hand-operated hoist is used to level the precast concrete beam segment (1.1). The hoisting is allowed to stand still for at least 5 minutes, and the hoisting point and the precast concrete beam segment (1.1) are observed. If the hoisting point is firm and the precast concrete beam segment (1.1) is in a stable state, the hoisting can continue.

8. The construction method for a high-rise, large-span cantilevered concrete structure according to claim 1, characterized in that: In step nine, the specific process of dismantling the support frame (11) is as follows: Step 1, after the hoisting slings on the support frame (11) are connected, the suspended basket (12) in the installation area is removed, and the support frame (11) is lowered vertically by a tower crane by 1.5 to 2 meters; the construction personnel adjust the direction of the support frame (11) in the opening area with the help of guy ropes or steel pipes; Step 2, after the direction of the support frame (11) is adjusted, the support frame (11) is raised vertically by a tower crane to a position 200 mm to 250 mm above the cantilevered arc beam (1); Step 3, after the bottom of the support frame exceeds the upper surface of the cantilevered arc beam (1), the support frame (11) is moved horizontally out of the installation area of ​​the cantilevered arc beam (1) to the ground by a tower crane on site, and the support frame (11) is dismantled.

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