Construction method of cantilever hanging steel structure

Abstract

The invention provides a construction method of a cantilever hanging steel structure, which belongs to the technical field of building construction, and comprises the following steps: arranging a temporary jig frame at the outermost end of each floor of the cantilever hanging steel structure, carrying out positive-sequence installation construction from bottom to top, dismantling the temporary jig frame after the construction process is completely finished, and calculating the position of the cantilever hanging steel structure according to a calculation simulation result. A deformation preset value is set before each step of construction, so that it is guaranteed that all structural members fall to the designed positions after construction is completed; according to the construction method of the cantilever hanging steel structure, the problem that deformation is difficult to control in cantilever structure construction is solved, and the construction method has the advantages of being easy to operate, convenient, fast, reliable and high in applicability.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and particularly relates to a construction method for a cantilevered and suspended steel structure. Background Art

[0002] With the rapid development of China's economy, the public's demands for building quality, functionality, and aesthetics have been gradually increasing. Especially in the design of public buildings, not only is it required to have a beautiful appearance and a comfortable internal environment, but also higher requirements are put forward for the rationality of the internal space layout and the smoothness of the moving lines of the building. In order to meet these increasingly diverse demands, an innovative structural system - the cantilever - suspension structure system has been gradually introduced in building design in recent years. This structure creates a more open and unobstructed shared space by reducing the number of columns around the bottom layer, significantly improving the utilization rate of the building space and facilitating the smooth passage of people and goods. At the same time, suspension columns are set at the edges of the second floor and above to bear the load of the upper floor slab and are connected to the roof truss to balance the weight of the cantilever part, thereby ensuring the stability of the structure.

[0003] The most critical problem of the cantilever - suspension structure lies in the fact that there are significant differences between the stress state during the construction stage and the final stress state after the design is completed. This difference may lead to the accumulation of construction errors, ultimately affecting the overall closure of the structure and even possibly causing serious structural accidents during the construction process. In the normal use state of the design, the suspension columns are usually in a tensile state. In principle, it is required that after the support columns or shear walls are installed, the roof truss and the floor beams are installed sequentially from top to bottom.

[0004] However, if the suspension columns are installed in place before the roof truss is completed, they may be temporarily in a compressive state, thereby significantly weakening their bearing capacity. If the suspension columns are damaged and undergo irreversible deformation or failure at this stage, it will have a non - negligible impact on the stability of the entire structural system. As a result, the reinforced concrete floor slab on the cantilever platform is often in a tensile state. Especially as the construction height increases, the suspenders will transfer the load of the upper structure to the lower floors, which further increases the tensile stress of the lower floor slab concrete and increases the risk of floor slab cracking during the construction stage. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem that the deformation during the construction process of the cantilever suspension column structure in the prior art is difficult to control, and thus provide a construction method for a cantilevered and suspended steel structure.

[0006] To solve the above - mentioned technical problem, the present invention provides a construction method for a cantilevered and suspended steel structure, which is constructed in the positive order from bottom to top and includes the following steps:

[0007] For the construction of the first floor, build the first-floor support structure in the core area of the first floor and build the first-floor temporary falsework at the outermost end of the first floor.

[0008] For the construction of the standard floors, with the help of the first-floor support structure and the first-floor temporary falsework, build the standard-floor steel structure platform above the first floor, build the standard-floor support structure in the core area of the standard-floor steel structure platform, build the standard-floor temporary falsework and suspension columns at the outermost end of the standard-floor steel structure platform, and complete the standard-floor floor slab.

[0009] For the roof layer, with the help of the standard-floor support structure and the standard-floor temporary falsework, build the roof-layer steel structure platform above the standard floor and complete the roof-layer floor slab.

[0010] Remove the first-floor temporary falsework and the standard-floor temporary falsework to form a stable structure.

[0011] Among them, deformation preset values are set for the standard-floor steel structure platform and the roof-layer steel structure platform so that after construction is completed, all structural members can fall to the designed positions.

[0012] During the construction process, a bottom-up positive installation method is adopted. The first-floor support structure and the standard-floor support structure support the overall core area, and the first-floor temporary falsework and the standard-floor temporary falsework support the cantilevered area at the outermost end of the steel structure platform, making the construction process of the standard floors and the roof layer simpler and reducing the construction difficulty and complexity; when the first-floor temporary falsework and the standard-floor temporary falsework are removed, the standard-floor steel structure platform and the roof-layer steel structure platform deform, offsetting the deformation preset values set before construction, so that the structural members after each construction step can accurately fall to the designed positions; through the suspension columns, the roof-layer steel structure platform becomes the main load-bearing structure of the cantilevered area at the outermost end of the standard-floor steel structure platform, forming a stable cantilevered hanging structure and an overall structure, solving the problem that the deformation is difficult to control in the construction of the cantilevered hanging structure, reducing the risk of floor slab cracking, and compared with the existing construction technology, it can greatly improve the construction efficiency, quality and safety. The construction method of the cantilevered hanging steel structure provided by the present invention solves the problem that the deformation is difficult to control in the construction process of the existing cantilevered suspension column structure.

[0013] Optionally, before the construction starts, construction simulation and parameter design are carried out to determine the deformation preset values of the standard-floor steel structure platform and the roof-layer steel structure platform. Through the above settings, the deformation value after the construction of the cantilevered hanging steel structure can be calculated based on the construction simulation and parameter design, and the deformation preset values are designed according to the calculation results of the deformation displacement, so as to ensure that the structural members after each construction step can accurately fall to the designed positions.

[0014] Optionally, the setting of the deformation preset value is opposite to the actual deformation direction of the standard floor steel structure platform and the roof floor steel structure platform. Through the above settings, when the temporary falsework is demolished, the deformation displacements of the standard floor steel structure platform and the roof floor steel structure platform can be offset by the deformation preset value, so as to ensure that the structural members after each construction step can accurately fall to the designed positions.

[0015] Optionally, the length adjustment value of the suspension column is the difference between the deformation preset values of adjacent two floors. Through the above settings, the length of the suspension column can meet the deformation displacements of adjacent two floors, preventing the suspension column from being damaged during the formation of a stable structure.

[0016] Optionally, the standard floor steel structure platform includes: a floor steel beam system platform and a cantilever beam system. Both the floor steel beam system platform and the cantilever beam system are cross and longitudinal beam systems composed of steel structure beams, and the steel structure beams adopt I-shaped cross-sections. Through the above settings, by reasonably configuring load-bearing structures such as the floor steel beam system platform and the cantilever beam system, the entire steel structure system is ensured to have sufficient strength and stability.

[0017] Optionally, the floor slab is laid on the steel structure platform and is connected through stud bolts above the steel structure platform. Through the above settings, the stud bolts can strengthen the connection strength between the floor slab and the steel structure platform, ensuring that the entire steel structure system has sufficient strength and stability.

[0018] Optionally, the floor slab is set as a cast-in-place reinforced concrete floor slab. Through the above settings, the cast-in-place reinforced concrete floor slab can fit better with the steel structure platform.

[0019] Optionally, the support structure includes: support columns or shear walls, and the support columns or shear walls adopt reinforced concrete structures. Through the above settings, the load-bearing structures in the core area are reasonably configured to ensure that the load-bearing performance of the support columns or shear walls does not exceed the limit during the construction process, and to ensure that the entire steel structure system has sufficient strength and stability.

[0020] Optionally, the ground floor temporary falsework and the standard floor temporary falsework are set as lattice columns. Through the above settings, the lattice columns have the advantages of strong bending resistance and good stability, can provide stable support for the cantilever area during the construction process, simplify the construction process of the standard floor and the roof floor, and reduce the construction difficulty and complexity.

[0021] Optionally, after the temporary falsework is demolished, the non-structural components are installed. Through the above settings, it is avoided that the non-structural components affect the demolition of the temporary falsework. Description of the Drawings

[0022] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0023] Figure 1 Schematic diagram of an embodiment of the cantilever hanging steel structure provided in the embodiment of the present invention;

[0024] Figure 2 For Figure 1 Schematic diagram of the construction of the first standard floor in

[0025] Figure 3 For Figure 1 Schematic diagram of the construction of the second standard floor in

[0026] Figure 4 For Figure 1 Schematic diagram of the construction of the roof floor in

[0027] Figure 5 For Figure 1 Schematic diagram of the deformed shape after construction when the construction pre-adjustment value is not set for the cantilever hanging steel structure in

[0028] Figure 6 For Figure 1 Schematic diagram of the design of the deformation preset value for the cantilever hanging steel structure in

[0029] Explanation of the reference numerals in the drawings:

[0030] 1. First floor; 11. First floor support structure; 12. First floor temporary falsework; 2. Standard floor; 21. Standard floor steel structure platform; 22. Standard floor slab; 23. Standard floor support structure; 24. Standard floor temporary falsework; 3. Suspended column; 4. Roof floor; 41. Roof floor steel structure platform; 42. Roof floor slab. Specific embodiments

[0031] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] This embodiment provides a construction method for cantilevered hanging steel structures that can solve the problem of difficult-to-control deformation during the construction of cantilevered hanging structures, and is used to reduce the risk of floor cracking.

[0036] like Figures 1-6 As shown, a specific implementation method of a cantilever hanging steel structure construction method provided in this embodiment is constructed in a positive order from bottom to top, including the following steps:

[0037] Construction of the first floor 1: building a first floor support structure 11 in the core area of ​​the first floor 1, and building a first floor temporary frame 12 at the outermost end of the first floor 1;

[0038] Construction of standard floor 2: With the help of the first floor support structure 11 and the first floor temporary frame 12, a standard floor steel structure platform 21 is built above the first floor 1, a standard floor support structure 23 is built in the core area of ​​the standard floor steel structure platform 21, a standard floor temporary frame 24 and a sling 3 are built at the outermost end of the standard floor steel structure platform 21, and the standard floor slab 22 is completed;

[0039] Roof layer 4, with the help of standard layer support structure 23 and standard layer temporary frame 24, a roof layer steel structure platform 41 is built above the standard layer 2, and the roof layer floor 42 is completed;

[0040] The temporary tire frame 12 of the first layer and the temporary tire frame 24 of the standard layer are removed to form a stable structure;

[0041] Among them, deformation preset values are set for the standard floor steel structure platform 21 and the roof floor steel structure platform 41 so that after construction is completed, all structural members can fall to the designed positions.

[0042] During the construction process, a bottom-up sequential installation method is adopted. The first-floor support structure 11 and the standard floor support structure 23 support the overall core area, and the first-floor temporary falsework 12 and the standard floor temporary falsework 24 support the cantilever area at the outermost end of the steel structure platform, making the construction process of the standard floor 2 and the roof floor 4 simpler and reducing the construction difficulty and complexity; when the first-floor temporary falsework 12 and the standard floor temporary falsework 24 are removed, the standard floor steel structure platform 21 and the roof floor steel structure platform 41 deform to offset the deformation preset value set before construction, so that the structural members after each construction step can accurately fall to the designed positions; through the suspension column 3, the roof floor steel structure platform 41 becomes the main load-bearing structure of the cantilever area at the outermost end of the standard floor steel structure platform 21, forming a stable cantilever suspension structure and an integral structure, solving the problem that the deformation is difficult to control during the construction of the cantilever suspension structure, reducing the risk of floor slab cracking, and compared with the existing construction technology, the construction efficiency, quality and safety can be greatly improved. The construction method of the cantilever suspension steel structure provided in this embodiment solves the problem that the deformation is difficult to control during the construction process of the existing cantilever suspension column 3 structure.

[0043] It should be supplemented that one or more standard floors 2 can be set according to the design requirements. For example Figures 1-6 As shown, taking the example of setting two standard floors 2 to form a three-story steel structure building.

[0044] Specifically, the suspension column 3 generally uses high-strength steel as the main load-bearing material.

[0045] For example Figure 5 、 Figure 6As shown in the figure, in the construction method of the cantilevered hanging steel structure provided in this embodiment, before the construction starts, construction simulation and parameter design are carried out to determine the deformation preset values of the steel structure platform 21 of the standard floor and the steel structure platform 41 of the roof floor. With the aid of large-scale finite element design analysis software, construction simulation is carried out, and the deformation value after the construction of the cantilevered hanging steel structure is calculated. It is judged whether the stress of the components during the construction exceeds the limit (if it exceeds the limit, methods such as replacing the rods should be used for iterative calculation multiple times to ensure that the stress does not exceed the limit during the whole process), and the deformation preset value and the cutting length of the components are designed based on the displacement calculation results. When calculating and simulating, the superposition effect of the installation sequence and the load accumulation effect should be considered. In particular, the influence of the change in the concrete stiffness during the floor concrete pouring process and the influence of the falsework on the structural deformation should be considered. According to the construction simulation and parameter design, and based on the deformation displacement calculation results, the deformation preset value is designed to ensure that the structural components after each construction step can accurately fall to the designed position.

[0046] As Figure 5 、 Figure 6 shown in the figure, in the construction method of the cantilevered hanging steel structure provided in this embodiment, the setting direction of the deformation preset value is opposite to the actual deformation direction of the steel structure platform 21 of the standard floor and the steel structure platform 41 of the roof floor. When the temporary falsework is removed, the deformation displacements of the steel structure platform 21 of the standard floor and the steel structure platform 41 of the roof floor can be offset by the deformation preset value, so as to ensure that the structural components after each construction step can accurately fall to the designed position.

[0047] Specifically, during the construction process, the cantilevered hanging structure may produce obvious deformation under the action of gravity load, and this deformation will accumulate and increase with the progress of the construction. Similar to a continuous beam, if no additional deformation preset value is set, the center and edge of the floor slab may deflect downward, thus affecting the structural safety and normal use. The deformation shape is as Figure 5 shown in the figure. To avoid this situation, in principle, the construction pre-adjustment value should be set in the opposite direction of the structural deformation. Taking the three-story cantilevered hanging steel structure as an example, for instance, when the structure is working normally, the deformations at the connections between the second-story suspenders and the second-story steel beam platform and the third-story steel beam platform are δA and δB respectively, and the deformations at the connections between the third-story suspenders and the third-story steel beam platform and the roof floor 4 truss platform are δC and δD respectively. Then the construction pre-adjustment values are correspondingly set as upward δA, δB, δC, and δD, as Figure 6 shown in the figure.

[0048] It should be added that Figure 5 is an enlarged schematic diagram of the deformation shape, Figure 6 is an enlarged schematic diagram of the deformation preset value.

[0049] The calculation of the deformation preset value should adopt the complete structural calculation model including steel structural members, floor slabs, curtain walls and other components. The load considers the self-weight of the steel structure, floor slab and curtain wall, and conducts the overall structural deformation analysis. It is calculated in combination with the load action process during the construction stage of the structure and the participation degree of the stiffness of the floor slab concrete pouring construction stage. Finally, it is ensured that after the construction is completed, the cantilever end falls to the designed elevation.

[0050] As Figure 5 , Figure 6 shown, in the construction method of the cantilever hanging steel structure provided by this embodiment, the length adjustment value of the suspension column 3 is the difference between the deformation preset values of adjacent two floors. It can make the length of the suspension column 3 meet the deformation displacement of adjacent two floors, and prevent the suspension column 3 from being damaged during the process of forming a stable structure.

[0051] Specifically, the corresponding length of the suspension column 3 should also be adjusted according to the deformation during cutting. For example, the suspension column 3 on the third floor should be adjusted by δD - δC on the basis of the original length, and the suspension column 3 on the second floor should be adjusted by δB - δA on the basis of the original length.

[0052] As Figure 1 shown, in the construction method of the cantilever hanging steel structure provided by this embodiment, the standard floor steel structure platform 21 includes: a floor steel beam system platform and a cantilever beam system. Both the floor steel beam system platform and the cantilever beam system are cross and longitudinal beam systems composed of steel structure beams, and the steel structure beams adopt I-shaped cross-sections. By reasonably configuring load-bearing structures such as the floor steel beam system platform and the cantilever beam system, it is ensured that the entire steel structure system has sufficient strength and stability. In addition, as an alternative implementation method, the steel structure beam can also adopt a square cross-section or other cross-section forms.

[0053] As Figure 1 shown, in the construction method of the cantilever hanging steel structure provided by this embodiment, the floor slab is laid on the steel structure platform and is connected through the stud above the steel structure platform. The stud can enhance the connection strength between the floor slab and the steel structure platform, and ensure that the entire steel structure system has sufficient strength and stability.

[0054] As Figure 1 shown, in the construction method of the cantilever hanging steel structure provided by this embodiment, the floor slab is set as a cast-in-place reinforced concrete floor slab. The cast-in-place reinforced concrete floor slab can fit better with the steel structure platform. In addition, as an alternative implementation method, the floor slab can adopt a precast reinforced concrete floor slab according to the design and actual construction needs.

[0055] As Figure 1As shown in the figure, in the construction method of the cantilevered and suspended steel structure provided in this embodiment, the support structure includes: support columns or shear walls, and the support columns or shear walls adopt reinforced concrete structures. The load-bearing structures in the core area are reasonably configured to ensure that the load-bearing performance of the support columns or shear walls during construction does not exceed the limit, and to ensure that the entire steel structure system has sufficient strength and stability. Additionally, as an alternative implementation, the support columns or shear walls can also adopt steel-concrete composite structures.

[0056] As Figure 1 shown in the figure, in the construction method of the cantilevered and suspended steel structure provided in this embodiment, the first-floor temporary falsework 12 and the standard-floor temporary falsework 24 are set as lattice columns. Lattice columns have the advantages of strong bending resistance and good stability, and can provide stable support for the cantilevered area during construction, making the construction process of the standard floor 2 and the roof floor 4 simpler and reducing the construction difficulty and complexity. Specifically, the lattice columns are formed by connecting multiple steel structure members. Additionally, as an alternative implementation, the first-floor temporary falsework 12 and the standard-floor temporary falsework 24 can also be set as scaffolds or other detachable temporary support structures.

[0057] In the construction method of the cantilevered and suspended steel structure provided in this embodiment, after the temporary falsework is removed, non-structural components are installed. Avoid non-structural components affecting the removal of the temporary falsework. The non-structural components include curtain walls, etc.

[0058] Taking the three-story cantilevered and suspended steel structure as an example, the specific construction steps are as follows:

[0059] S1. Conduct construction simulation with the help of large-scale finite element design and analysis software, calculate the deformation value after the construction of the complex cantilevered-suspended steel structure is completed, judge whether the stress of the components during construction exceeds the limit (if it exceeds the limit, methods such as replacing rods should be used for multiple iterative calculations to ensure that the stress does not exceed the limit throughout the process), and design the construction pre-adjustment value and the cutting length of the components based on the displacement calculation results. When calculating and simulating, the influence of the installation sequence and the superposition effect of the load accumulation effect should be considered, especially the influence of the change in concrete stiffness during the floor concrete pouring process, and the influence of the falsework on the structural deformation.

[0060] S2. With the help of the first-floor temporary falsework 12, complete the construction of the second-floor floor steel beam system platform, cantilever beam system, and internal columns, and then complete the pouring of the second-floor reinforced concrete floor slab.

[0061] S3. With the help of the second-floor temporary falsework, complete the construction of the third-floor floor steel beam system platform, cantilever beam system, internal columns, and suspension columns 3, and then complete the pouring of the third-floor reinforced concrete floor slab.

[0062] S4. With the help of the third-floor temporary falsework, complete the installation of the roof steel truss, and then complete the pouring of the roof floor 4 reinforced concrete floor slab.

[0063] S5. Demolish all falsework.

[0064] S6. Install other non-structural components such as curtain walls.

[0065] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A construction method for cantilevered hanging steel structure, characterized in that: The construction process from bottom to top includes the following steps: Construction of the first floor (1), building a first floor support structure (11) in the core area of ​​the first floor (1), and building a first floor temporary frame (12) at the outermost end of the first floor (1); During the construction of the standard floor (2), a standard floor steel structure platform (21) is built above the first floor (1) with the aid of the first floor support structure (11) and the first floor temporary frame (12), a standard floor support structure (23) is built in the core area of ​​the standard floor steel structure platform (21), a standard floor temporary frame (24) and a sling (3) are built at the outermost end of the standard floor steel structure platform (21), and the standard floor slab (22) is completed; The roof layer (4) is constructed by using a standard layer support structure (23) and a standard layer temporary frame (24) to build a roof layer steel structure platform (41) above the standard layer (2) and complete the roof layer floor slab (42); The temporary tire frame (12) of the first layer and the temporary tire frame (24) of the standard layer are removed to form a stable structure; The standard layer steel structure platform (21) and the roof layer steel structure platform (41) are provided with preset deformation values ​​so that all structural components can fall into the designed positions after the construction is completed.

2. The construction method of cantilever hanging steel structure according to claim 1 is characterized in that: Before construction begins, construction simulation and parameter design are performed to determine the preset deformation values ​​of the standard layer steel structure platform (21) and the roof layer steel structure platform (41).

3. The construction method of cantilevered hanging steel structure according to claim 2 is characterized in that: The setting of the deformation preset value is opposite to the actual deformation direction of the standard layer steel structure platform (21) and the roof layer steel structure platform (41).

4. The construction method of cantilevered hanging steel structure according to claim 2 is characterized in that: The length adjustment value of the suspension column (3) is the difference between the deformation preset values ​​of two adjacent layers.

5. The construction method of cantilever hanging steel structure according to claim 1 is characterized in that: The standard-layer steel structure platform (21) comprises: a floor steel beam system platform and a cantilever beam system. Both the floor steel beam system platform and the cantilever beam system are longitudinal and transverse beam systems composed of steel structure beams. The steel structure beams adopt I-shaped cross-sections.

6. The construction method of cantilevered hanging steel structure according to claim 1 is characterized in that: The floor slab is laid on the steel structure platform and connected by bolts above the steel structure platform.

7. The construction method of cantilevered hanging steel structure according to claim 6 is characterized in that: The floor slab is configured as a reinforced concrete floor slab cast on site.

8. The construction method of cantilevered hanging steel structure according to claim 1 is characterized in that: The supporting structure includes: supporting columns or shear walls, and the supporting columns or shear walls are reinforced concrete structures.

9. The construction method of cantilevered hanging steel structure according to claim 1 is characterized in that: The first-layer temporary tire frame (12) and the standard-layer temporary tire frame (24) are configured as lattice columns.

10. The construction method of cantilever hanging steel structure according to any one of claims 1 to 9, characterized in that: After removing the temporary tire frame, install non-structural components.

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