Cumulative lifting method for outward expansion assembly of large-span and large-drop curved steel grid

Abstract

A method for assembling and cumulatively lifting a large-span, large-drop curved steel grid for expansion, including: determining the positions of each lifting point, assembling a number of lifting devices at preset positions on the main steel structure according to the lifting point positions; connecting the first end of the initial grid structure to the corresponding lifting device, supporting the area of ​​the initial grid structure near the second end with an assembly cradle so that the second end of the initial grid structure remains at a first preset height; lifting the first end of the initial grid structure to a second preset height using the lifting device; assembling grid unit structures at both ends of the initial grid structure to form an intermediate grid structure; and finally lifting the final grid structure to a preset elevation using the lifting device. This method for assembling and cumulatively lifting a large-span, large-drop curved steel grid for expansion has high construction quality, effectively improves construction efficiency, ensures construction progress, and brings certain economic benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of grid construction, and in particular to a method for assembling and cumulatively lifting a large-span and large-drop curved steel grid with outward expansion. Background Art

[0002] The main steel structure projects in the construction of building projects are all sub-projects with higher risks. Steel grids are one of the structural forms. The main construction methods include high-altitude bulk installation, block hoisting, top (lifting) and sliding. When the steel grid structure has the characteristics of large span, large drop and curved surface, the above construction methods will have the disadvantages of many high-altitude operations, many safety hazards and low construction efficiency. They are not suitable for the construction of large-span, large-drop and curved steel grids. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a method for assembling and cumulatively lifting a large-span and large-drop curved steel grid with high construction quality, effectively improving construction efficiency, ensuring construction progress, and bringing certain economic benefits.

[0004] The present invention provides a large-span and large-drop steel grid outward expansion assembly cumulative lifting method, comprising the following steps:

[0005] S1, determine the positions of each lifting point, and assemble several lifting equipment at the preset positions of the main steel structure according to the positions of the lifting points;

[0006] S2, connecting the first end of the initial grid structure to a corresponding lifting device, and supporting the area of ​​the initial grid structure near its second end by an assembled tire frame so that the second end of the initial grid structure is maintained at a first preset height;

[0007] S3, lifting the first end of the initial grid structure to a second preset height by a lifting device, and during the lifting process, the second end of the initial grid structure remains stationary as a base point for rotation of the initial grid structure;

[0008] S4, assembling grid unit structures at both ends of the initial grid structure to form an intermediate grid structure;

[0009] S5, repeating steps S2 to S4 until the initial grid structure reaches a preset length to form a final grid structure;

[0010] S6, lift the final grid structure to the preset elevation using lifting equipment.

[0011] In one embodiment, the lifting equipment in step S1 is installed on two opposite sides of the top of the main steel structure and in the middle of the main steel structure.

[0012] In one embodiment, step S3, wherein the first end of the initial grid structure is lifted to a second preset height by a lifting device, and the second end of the initial grid structure remains stationary as a base point for rotation of the initial grid structure during the lifting process, further comprises:

[0013] S301, rotatably connecting the second end of the initial grid structure to the assembly frame;

[0014] S302, lifting the first end of the initial grid structure to a second preset height by a lifting device;

[0015] S303: rigidly connect the initial grid structure to the main steel structure.

[0016] In one embodiment, the step S4 of assembling grid unit structures at both ends of the initial grid structure to form an intermediate grid structure further includes:

[0017] S401, measuring and obtaining the positions of the installation nodes at both ends of the initial grid structure;

[0018] S402 , first welding the grid unit structure at the position of the installation node at the second end of the initial grid structure, and then welding the grid unit structure at the position of the installation node at the first end of the initial grid structure.

[0019] In one embodiment, when the grid unit structure is welded in step S402 , the lower chord of the grid unit structure is welded first, and then the upper chord of the grid unit structure is welded.

[0020] In one embodiment, when there are multiple assembled tire frames in step S2, the assembled tire frames are tied together.

[0021] In one embodiment, the assembled cradle in step S2 is connected to the bottom of the lower chord-ball node at a corresponding position of the initial grid structure.

[0022] In one embodiment, the method for assembling and cumulatively lifting the outward expansion of the large-span and large-drop curved steel grid further includes step S7, performing a backfill operation on the final grid structure.

[0023] The present invention provides a method for assembling and cumulatively lifting a large-span, large-drop curved steel grid structure by expanding outward from the middle to both ends during the cumulative lifting process. Most of the work can be transferred to the ground, and only a small number of assembly cradles are needed to support the second end of the grid structure, thereby reducing the use of assembly cradles and other construction measures. The method is suitable for the construction of large-span, large-drop curved steel grid structures, can reduce safety hazards, improve construction quality, effectively improve construction efficiency, ensure construction progress, and bring certain economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a flow chart of the cumulative lifting method for the outward expansion assembly of a large-span, large-drop curved steel grid.

[0026] Figure 2 Schematic diagram of the positions of the initial grid structure and the main steel structure when determining the hanging point positions in the initial state.

[0027] Figure 3 This is a structural schematic diagram of an initial grid structure where both ends are located at a first preset height and a second preset height respectively.

[0028] Figure 4 This is a schematic diagram of the structure at preset heights at both ends after the middle grid structure is assembled.

[0029] Figure 5 This is a structural diagram after the final grid structure is assembled.

[0030] Figure 6 This is a structural diagram of the final grid structure being lifted to the preset elevation. DETAILED DESCRIPTION

[0031] Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are merely some, and not all, of the embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the description of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0032] In the description of the present invention, unless otherwise specified or limited, the terms "disposed," "installed," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; and direct or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of these terms based on the specific circumstances.

[0033] The directions or positional relationships indicated by terms such as "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience and simplification of description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0034] The terms "first," "second," "third," etc. are merely used to distinguish elements of similar nature and do not indicate or imply relative importance or a particular order.

[0035] The terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of elements other than the listed elements and may also include additional elements not specifically listed.

[0036] First embodiment

[0037] Please refer to Figure 1 The first embodiment of the present invention provides a method for assembling and accumulating the expansion of a large-span, large-drop curved steel grid, comprising the following steps:

[0038] S1, determining the positions of each lifting point, and assembling a plurality of lifting devices 2 at preset positions of the main steel structure 4 according to the positions of the lifting points.

[0039] It can be known that the position of the lifting point is determined to determine the position of each lifting point on the complete grid structure. The complete grid structure in this embodiment is the final grid structure 6 in step S6. The lifting point position can be at both ends and several positions in the middle of the complete grid structure. The corresponding lifting equipment 2 is assembled on the opposite sides of the top of the main steel structure 4 and at several positions in the middle of the main steel structure 4. The lifting point can generally be the bottom of the lower chord ball node of the grid structure 1, and the lifting equipment 2 can be located directly above the corresponding lower chord ball node. By being hoisted at the bottom of the lower chord ball node, the stress of the hoisting can be dispersed to various positions of the grid structure.

[0040] S2, connecting the first end of the initial grid structure 1 to the corresponding lifting device 2, and supporting the area of ​​the initial grid structure 1 near the second end by the assembling frame 3 so that the second end of the initial grid structure 1 is maintained at a first preset height.

[0041] Understandably, see Figure 2 In this embodiment, the first end of the initial grid structure 1 is Figure 2 The end portion on the right side of the initial grid structure 1, the second end of the initial grid structure 1 is Figure 2At the left end of the initial grid structure 1, in the initial state, the initial grid structure 1 is supported by an assembling frame 3, which is arranged at the bottom of the lower chord ball node in the second end area of ​​the initial grid structure 1. The assembling frame 3 can be a structure including a height-adjustable circular tube structure and a T-shaped base connected to the circular tube structure. The circular tube structure can be adjusted to keep the second end of the initial grid structure 1 at a preset first preset height.

[0042] S3, lifting the first end of the initial grid structure 1 to a second preset height by the lifting device 2, and during the lifting process, the second end of the initial grid structure 1 remains stationary as the base point for the rotation of the initial grid structure 1.

[0043] To know, please refer to Figure 3 , the above steps further include:

[0044] S301, rotatably connecting the second end of the initial grid structure 1 to the assembly frame 3;

[0045] S302, lifting the first end of the initial grid structure 1 to a second preset height using the lifting device 2, and monitoring the height, levelness, and deflection of the initial grid structure 1 during the lifting process;

[0046] S303 , rigidly connecting the initial grid structure 1 and the main steel structure 1 .

[0047] It can be known that the so-called rigid connection can be achieved by welding the initial grid structure 1 and the main steel structure 4 through steel pipe components, thereby improving the stability of the initial grid structure 1, facilitating the subsequent splicing of the grid unit structure, and avoiding shaking and displacement during the welding process.

[0048] S4, assembling grid unit structures at both ends of the initial grid structure 1 to form an intermediate grid structure 5.

[0049] To know, please refer to Figure 4 , the assembly details of the grid unit structure further include:

[0050] S401, measuring and obtaining the positions of the installation nodes at both ends of the initial grid structure 1. The measured parameters may include height, levelness, and deflection to ensure the accuracy of assembly;

[0051] S402 , first welding the grid unit structure at the installation node position of the second end of the initial grid structure 1 , and then correspondingly welding the grid unit structure at the installation node position of the first end of the initial grid structure 1 .

[0052] It can be seen that when the truss unit structure is welded in step S402, the lower chord of the truss unit structure is welded first, and then the upper chord of the truss unit structure is welded. The lower chord can play a certain supporting role in the welding process of the upper chord, thereby improving the convenience of welding.

[0053] S5 , repeating steps S2 to S4 until the initial grid structure 1 reaches a preset length to form a final grid structure 6 .

[0054] See also Figure 4 It can be understood that when carrying out the next step of lifting, the rigid connection structure between the intermediate grid structure 5 and the main steel structure is first removed, and then the lifting equipment is connected to the first end of the intermediate grid structure 5, and the assembly tire frame is connected to the second end of the intermediate grid structure 5, and then the two ends of the intermediate grid structure 5 are lifted to the preset heights respectively through the lifting equipment 2 and the assembly tire frame, and then the grid unit structure is welded until the final grid structure 6 is formed.

[0055] See also Figure 5 and Figure 6 , S6, lift the final grid structure 6 to a preset elevation through lifting equipment.

[0056] S7, perform supplementary work on the final grid structure.

[0057] It can be known that the filling operation in this embodiment is to connect the connecting rods between the grid structure and the main steel structure to complete the unloading of the lifting force of the lifting equipment. The unloading is also a graded unloading, that is, the lifting force with smaller force is unloaded first, and each lifter is graded and unloaded to 100%, so that the steel strands of each lifting equipment are no longer under stress. At this time, the load of the grid structure is completely transferred to the main steel structure, and the structural stress form is converted into the design working condition. Afterwards, the lifting equipment is dismantled and the construction operation is completed.

[0058] After the filling operation is completed, the final grid structure will be welded and fixed to the main steel structure.

[0059] From the above description, it can be known that the method for assembling and cumulatively lifting the outward expansion of the large-span and large-drop curved steel grid provided by the present invention, during the cumulative lifting process, the grid structure is assembled by expanding outward from the middle to both ends, most of the work can be transferred to the ground, and only a small number of assembly frames are needed to support the second end of the grid structure, reducing the use of assembly frames and other construction measures. It is suitable for the construction of large-span and large-drop curved steel grids, can reduce safety hazards, improve construction quality, and effectively improve construction efficiency, ensure construction progress, and bring certain economic benefits.

[0060] The foregoing description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein are intended to be encompassed within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for assembling and accumulating steel grid frames with large spans and large drops, characterized in that: The steps include: S1, determine the positions of each lifting point, and assemble several lifting equipment at the preset positions of the main steel structure according to the positions of the lifting points; S2, connecting the first end of the initial grid structure to a corresponding lifting device, and supporting the area of ​​the initial grid structure near its second end by an assembled tire frame so that the second end of the initial grid structure is maintained at a first preset height; S3, lifting the first end of the initial grid structure to a second preset height by a lifting device, and during the lifting process, the second end of the initial grid structure remains stationary as a base point for rotation of the initial grid structure; S4, assembling grid unit structures at both ends of the initial grid structure to form an intermediate grid structure; S5, repeating steps S2 to S4 until the initial grid structure reaches a preset length to form a final grid structure; S6, lift the final grid structure to the preset elevation using lifting equipment.

2. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 1 is characterized in that: The lifting equipment in step S1 is assembled on two opposite sides of the top of the main steel structure and in the middle of the main steel structure.

3. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 2 is characterized in that: The step S3, wherein the first end of the initial grid structure is lifted to a second preset height by a lifting device, and the second end of the initial grid structure is kept stationary as a base point for rotation of the initial grid structure during the lifting process, further comprises: S301, rotatably connecting the second end of the initial grid structure to the assembly frame; S302, lifting the first end of the initial grid structure to a second preset height by a lifting device; S303: rigidly connect the initial grid structure to the main steel structure.

4. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 3 is characterized in that: The step S4, assembling grid unit structures at both ends of the initial grid structure to form an intermediate grid structure, further comprises: S401, measuring and obtaining the positions of the installation nodes at both ends of the initial grid structure; S402 , first welding the grid unit structure at the position of the installation node at the second end of the initial grid structure, and then welding the grid unit structure at the position of the installation node at the first end of the initial grid structure.

5. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 4 is characterized in that: When the grid unit structure is welded in step S402, the lower chord of the grid unit structure is welded first, and then the upper chord of the grid unit structure is welded.

6. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 1 is characterized in that: When there are multiple assembled tire frames in step S2, the assembled tire frames are tied together.

7. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 1 is characterized in that: The assembled cradle in step S2 is connected to the bottom of the lower chord ball node at the corresponding position of the initial grid structure.

8. The method for assembling and accumulating the expansion of a large-span and large-drop curved steel grid as claimed in claim 1 is characterized in that: The method for assembling and cumulatively lifting the outward expansion of the large-span and large-drop curved steel grid structure further includes step S7, performing a backfill operation on the final grid structure.

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