In-situ installation method of a large-span steel truss multi-layer under-hanging steel structure

Abstract

The present invention relates to an in-situ installation method for a large-span steel truss multi-layer hanging steel structure, which adopts a supporting frame in-situ installation method. This method has a wide range of project applications, and is particularly suitable for scenes where the hanging area is located on the top plate of the basement and the mechanical position is limited. The core of the supporting frame in-situ installation method is to use a temporary supporting structure (i.e., the supporting frame) as an auxiliary to the main structure to achieve in-situ installation and splicing of the steel structure. This method shows significant advantages in terms of saving construction time, safety assurance, and economic rationality. It can not only effectively shorten the project period, but also reduce construction costs while ensuring construction safety, thereby improving social and economic benefits for enterprises.

Description

Technical Field

[0001] The invention relates to the technical field of building engineering construction, in particular to an in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure. Background Art

[0002] With the continuous advancement of modern construction engineering technology, the application of large-span steel truss under-hanging steel structures has become increasingly widespread. This structural form has become an important means of creating open interior spaces and eye-catching architectural appearances with its unique aesthetic and practical advantages. Especially in large public buildings such as stations, airports, stadiums, exhibition centers, and commercial buildings, the design of large-span under-hanging steel structures not only improves the efficiency of space use, but also gives the building an iconic appearance. Faced with the installation challenges of this special structural form, the choice of construction method is particularly critical. The overall lifting method, the inverted lifting method, and the upright installation method are several main construction methods. They each have their own characteristics, and the most appropriate solution needs to be selected based on the actual situation of the project and technical and economic analysis. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide an in-situ installation method for a large-span steel truss multi-layer under-hanging steel structure, which adopts the method of in-situ upright installation of a supporting frame for construction; compared with the inverted lifting and overall lifting methods, this method has a wider range of applications and fewer limitations. It can not only effectively shorten the project period, but also reduce the cost of construction measures while ensuring construction safety, thereby significantly improving the economic benefits for the enterprise.

[0004] The technical solution adopted by the present invention to solve its technical problems is: to provide an in-situ installation method for a large-span steel truss multi-layer under-hanging steel structure, characterized in that: it includes a conventional structure area and a core tube area, a truss layer of a steel structure is arranged at the top of the conventional structure area and the core tube area, the truss layer is connected to the under-hanging structure area through a hanging column, the under-hanging structure area adopts a support frame for in-situ positive installation sequence construction, the support frame is arranged from the bottom plate of the structural foundation, and an intelligent construction monitoring system is arranged after the installation of the under-hanging structure area and the truss layer is completed. The intelligent construction monitoring system mainly monitors the stress and deformation of the structure when the support frame is unloaded and when the concrete of the floor of the under-hanging structure area is poured, so as to ensure the safety of the structural construction;

[0005] The installation method includes the following specific steps:

[0006] S1. Foundation review: Before installing the support frame, carefully review and calculate the foundation bearing capacity based on the design drawings and geological survey reports;

[0007] S11. Construction of the foundation and surrounding structures of the lower hanging layer: If no foundation reinforcement is required after foundation review, the conventional structure area and core tube area around the foundation and the lower hanging layer shall be constructed according to normal procedures; if the foundation of the tire frame area needs to be reinforced, it shall be completed before the foundation construction;

[0008] S12. Support frame deepening: Use computer analysis software to design and verify the support frame according to the upper load before installation to determine the form, material specifications, fixing and connection measures of the support frame and the layout of the construction operation platform;

[0009] S2. Installation of support frame: Before formal installation, use construction simulation software to simulate the lifting, analyze the actual working conditions and mechanical positions on site, and formulate the best lifting plan; a construction operation platform should be set up on the top of the support frame for steel structure correction, welding operations, subsequent monitoring and unloading work;

[0010] S21. Acceptance of the support frame: After the installation of the support frame is completed, all parties involved in the construction shall be organized to conduct frame acceptance and keep acceptance records;

[0011] S22. Tire frame monitoring point arrangement: After the support tire frame is installed, the tire frame vertical and horizontal deformation monitoring points are arranged according to the monitoring implementation plan requirements, and each tire frame is arranged with no less than one monitoring point;

[0012] S3. Installation of the lower hanging structure area: Before installing the lower hanging structure area, you must fully understand the design drawings and the construction requirements of key connection nodes. To this end, you need to be familiar with the relevant design drawings and conduct in-depth design to ensure that all details can meet the actual construction requirements;

[0013] S31. Installation of the first column: The first column should be selected near the surrounding structure of the lower hanging layer. The first column is temporarily fixed at the bottom after lifting, re-measurement of elevation, accurate positioning, and verticality adjustment. Then, the four corners are tightened and stabilized with cables and wind ropes. After that, the beam connected to the column is connected to the surrounding structure. The wind ropes can be removed after a stable system is formed. Subsequent columns and beams are installed in an orderly manner relying on the stable columns and beams.

[0014] S32, floor deck installation: After the installation of columns and beams on each layer is completed, the steel truss floor decks of each layer below the hanging layer are interspersed. At the same time, to ensure safe construction, when installing the floor deck, the cross operation of column and beam installation should be avoided on the upper part;

[0015] S4. Installation of truss layer: The truss layer is installed and constructed by bulk loading in the air; most of the steel trusses are overweight components, so the selection of lifting equipment and reasonable segmentation of components should be done in combination with the specific project, and the number of welded joints should be reduced while meeting the lifting requirements and transportation capacity;

[0016] S5. Layout of intelligent construction monitoring system: After the installation of the truss layer is completed, the monitoring points are arranged. The monitoring contents include stress monitoring of the main load-bearing components and vertical deformation monitoring. The monitoring period is from the completion of the installation of the truss layer to the completion of the pouring of the floor deck concrete.

[0017] S6, Unloading: Unloading is carried out by hydraulic overall synchronous graded unloading. During the whole unloading process, the principle of "deformation coordination and unloading balance" must be followed to avoid temporary support overload instability or partial overall damage to the structure due to instantaneous overload of individual support points;

[0018] S7, pouring of floor slab concrete: after unloading, start pouring concrete for each floor of the lower hanging layer. In order to minimize the impact of deformation on concrete and facilitate waterproofing, the concrete of the top roof should be poured last; the pouring order of other layers can be formulated according to the specific conditions of the project to ensure the efficiency and safety of the entire construction process;

[0019] S8, dismantling of the support frame: the support frame will be dismantled after the concrete pouring of the floor is completed and the monitoring data is normal;

[0020] S9. Acceptance: After each process is completed and relevant tests are passed, acceptance will be organized according to the acceptance specifications.

[0021] As a supplement to the technical solution described in the present invention, in S1, the load value during the foundation review should include the deadweight of the tire frame itself, the deadweight of the structure above the tire frame, the possible wind load and the temporary load generated during the construction process; when the reviewed foundation load cannot meet the requirements, it is necessary to consult with the design team to take appropriate foundation reinforcement measures.

[0022] As a supplement to the technical solution described in the present invention, in the above S22, the initial monitoring data is measured and recorded after the tire frame is installed, and the monitoring is stopped until the unloading is completed, and the monitoring is performed every 3 to 5 days.

[0023] As a supplement to the technical solution described in the present invention, in the above S3, after the detailed design is completed, the drawings should be submitted to the original design unit for review and confirmation; only after obtaining the approval of the design unit can the components be processed and implemented according to these drawings to ensure the construction quality and the complete realization of the design intent; when installing the first-floor columns, a pad with a thickness corresponding to the designed arch value should be set at the bottom of the columns that need to be pre-arched.

[0024] As a supplement to the technical solution described in the present invention, in the S32, after installing the floor decking of the lower hanging layer, in order to ensure that the force system can be normally converted after unloading, the pouring of the floor concrete should be temporarily shelved and carried out after the structure is unloaded; this can ensure the stability of the structure during loading and unloading, and avoid affecting the force performance and safety of the structure due to premature pouring of concrete.

[0025] As a supplement to the technical solution described in the present invention, in the above S5, the construction monitoring system uses an intelligent monitoring system, which can remotely collect stress and deformation data of the main load-bearing components in real time and make analysis and decisions in time.

[0026] Beneficial effects: The present invention relates to an in-situ installation method for a large-span steel truss multi-layer under-hanging steel structure, which adopts an in-situ upright installation method of a supporting frame for construction; compared with the inverted lifting and overall lifting methods, this method has a wider range of applications and fewer limitations. It can not only effectively shorten the project period, but also reduce the cost of construction measures while ensuring construction safety, thereby significantly improving the economic benefits for the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a flow chart of the steps of the present invention;

[0028] Figure 2 It is a schematic diagram of the construction of the foundation and the surrounding structure of the lower hanging layer according to the present invention;

[0029] Figure 3 is a schematic diagram of the installation of the support tire frame of the present invention;

[0030] Figure 4 It is a schematic diagram of the installation of the lower hanging layer structure of the present invention;

[0031] Figure 5 is a schematic diagram of the installation of the steel truss layer according to the present invention;

[0032] Figure 6 is a schematic diagram of the unloading of the present invention;

[0033] Figure 7 It is a schematic diagram of pouring concrete of the lower hanging floor decking slab according to the present invention;

[0034] Figure 8 It is a structural schematic diagram of the dismantling of the supporting tire frame of the present invention;

[0035] Fig. 9 It is a schematic diagram of the top of the supporting tire frame described in the present invention.

[0036] Diagram: 1. Conventional structure area, 2. Core tube area, 3. Steel structure truss layer, 4. Lower hanging layer structure area, 5. Support cradle, 6. Structural foundation slab, 7. Hanging column, 51. Construction operation platform, 52. Pre-arch pad, 53. Jack, 54. Jack, 55. Steel shoulder beam, 56. Steel ladder, 57. Horizontal steel support. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0038] The embodiment of the present invention relates to an in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure, such as Figure 1-9 As shown, it includes a conventional structure area 1 and a core tube area 2. A truss layer 3 of a steel structure is arranged at the top of the conventional structure area 1 and the core tube area 2. The truss layer 3 is connected to the lower hanging layer structure area 4 through a sling 7. The lower hanging layer structure area 4 adopts a support tire frame 5 for in-situ positive installation sequence construction. The support tire frame 5 is arranged from the structural foundation bottom plate 6. After the lower hanging layer structure area 4 and the truss layer 3 are installed, an intelligent construction monitoring system is arranged. The intelligent construction monitoring system mainly monitors the stress and deformation of the structure when the support tire frame 5 is unloaded and when the concrete of the lower hanging layer structure area 4 is poured, so as to ensure the safety of the structural construction;

[0039] The installation method includes the following specific steps:

[0040] S1. Foundation review: Before installing the support frame 5, carefully review and calculate its foundation bearing capacity based on the design drawings and geological survey reports; the load value during foundation review should include the deadweight of the frame itself, the deadweight of the structure above the frame, possible wind loads, and temporary loads generated during the construction process; if the reviewed foundation load does not meet the requirements, consult with the design team to take appropriate foundation reinforcement measures;

[0041] S11. Construction of the foundation and surrounding structures of the lower hanging layer: If no foundation reinforcement is required after foundation review, the conventional structure area 1 and core tube area 2 around the foundation and the lower hanging layer shall be constructed according to normal procedures; if the foundation of the tire frame area needs to be reinforced, it shall be completed before the foundation construction;

[0042] S12, deepening of the support frame 5: using computer analysis software to design and verify the support frame 5 according to the upper load before installation, to determine the form, material specifications, fixing connection measures and layout of the construction operation platform 51 of the support frame 5;

[0043] S2. Installation of the support frame 5: Before the formal installation, the construction simulation software is used to simulate the lifting, and the actual working conditions and mechanical positions are analyzed to formulate the best lifting plan; the installation operation is usually carried out in accordance with the principle of "from inside to outside, from low to high, primary first and secondary later"; a construction operation platform 51 should be set on the top of the support frame 5 for steel structure correction, welding operation, subsequent monitoring and unloading work;

[0044] S21. Acceptance of the support frame 5: After the installation of the support frame 5 is completed, all parties involved in the construction shall be organized to conduct acceptance of the frame and make acceptance records;

[0045] S22. Tire frame monitoring point arrangement: After the support tire frame 5 is installed, the tire frame vertical and horizontal deformation monitoring points are arranged according to the monitoring implementation plan requirements, and each tire frame is arranged with no less than one monitoring point; the initial monitoring data is measured and recorded after the tire frame is installed, and the monitoring is stopped until the unloading is completed, and the monitoring is performed every 3 to 5 days;

[0046] S3. Installation of lower hanging structure area 4: Before installing the lower hanging structure area 4, the design drawings and key connection node construction requirements must be fully understood. To this end, it is necessary to be familiar with the relevant design drawings and conduct in-depth design to ensure that all details can meet the actual construction needs; after the in-depth design is completed, the drawings should be submitted to the original design unit for review and confirmation; only after obtaining the approval of the design unit can the components be processed and implemented according to these drawings to ensure the construction quality and the complete realization of the design intent; when installing the first-floor columns, a pad with a thickness corresponding to the designed arch value should be set at the bottom of the columns that need to be pre-arched;

[0047] S31. Installation of the first column: The first column should be selected near the surrounding structure of the lower hanging layer. The first column is temporarily fixed at the bottom after lifting, re-measurement of elevation, accurate positioning, and verticality adjustment. Then, the four corners are tightened and stabilized with cables and wind ropes. After that, the beam connected to the column is connected to the surrounding structure. The wind ropes can be removed after a stable system is formed. Subsequent columns and beams are installed in an orderly manner relying on the stable columns and beams.

[0048] S32, floor deck installation: After the installation of columns and beams on each layer is completed, the steel truss floor decks of each layer below the hanging layer are interspersed. At the same time, to ensure safe construction, when installing the floor deck, the cross operation of column and beam installation should be avoided on the upper part;

[0049] After installing the floor slab of the lower hanging layer, in order to ensure that the force system can be normally converted after unloading, the pouring of floor concrete should be temporarily shelved and carried out after the structure is unloaded; this can ensure the stability of the structure during loading and unloading, and avoid affecting the force performance and safety of the structure due to premature pouring of concrete;

[0050] S4, truss layer 3 installation: truss layer 3 is installed in bulk in the air; most of the steel trusses are overweight components, and the selection of lifting equipment and reasonable segmentation of components must be done in combination with the specific project, and the number of welded joints must be reduced while meeting the lifting requirements and transportation capacity;

[0051] S5. Layout of intelligent construction monitoring system: After the installation of truss layer 3 is completed, monitoring points are arranged. The monitoring contents include stress monitoring of main load-bearing components and vertical deformation monitoring. The monitoring period is from the completion of installation of truss layer 3 to the completion of concrete pouring of floor decking. The construction monitoring system should use an intelligent monitoring system, which can remotely collect stress and deformation data of main load-bearing components in real time and make analysis and decisions in time.

[0052] S6, Unloading: Unloading is carried out by hydraulic overall synchronous graded unloading. During the whole unloading process, the principle of "deformation coordination and unloading balance" must be followed to avoid temporary support overload instability or partial overall damage to the structure due to instantaneous overload of individual support points;

[0053] S7, pouring of floor slab concrete: after unloading, start pouring concrete for each floor of the lower hanging layer. In order to minimize the impact of deformation on concrete and facilitate waterproofing, the concrete of the top roof should be poured last; the pouring order of other layers can be formulated according to the specific conditions of the project to ensure the efficiency and safety of the entire construction process;

[0054] S8, dismantling of the support frame 5: the support frame 5 is dismantled after the pouring of floor concrete is completed and the monitoring data is normal;

[0055] S9. Acceptance: After each process is completed and relevant tests are passed, acceptance will be organized according to the acceptance specifications.

[0056] During the construction process, the main structure construction of the lower hanging layer and its surroundings covers the foundation slab, core tube and conventional structural parts connected to the lower hanging layer area. The construction process must ensure that the lower hanging layer can be effectively connected with the adjacent structural parts during the installation phase to form a stable overall structural system.

[0057] The arrangement of monitoring points after the support frame is installed refers to setting up special monitoring points on the support frame to continuously monitor the stability and safety of the support frame. At the same time, after the steel truss layer is installed, it is also necessary to set up monitoring points on it. These points are mainly used to monitor the stress and deformation of the key load-bearing components of the lower hanging layer area and the steel truss layer.

[0058] In addition, the measure of leaving the jacks on the virtual top after unloading is mentioned in the figure means that the jacks on the top of the support frame are not removed immediately after the unloading process is completed, but are temporarily retained. The purpose of this is to ensure that in the process of gradual loading of permanent loads such as concrete of the subsequent floor structure, if an adverse situation occurs, this pre-set emergency measure can be quickly taken to ensure the safety and stability of the structure.

[0059] Figure 2 :Construction of the surrounding structure of the foundation and the lower hanging layer; As shown in the figure, the verification and calculation of the support frame foundation should be completed before the construction of the surrounding structure of the foundation and the lower hanging layer, and the detailed design and confirmation of the frame should be completed before the installation of the support frame. The surrounding structure of the foundation and the lower hanging layer includes the structural foundation bottom plate 6, the conventional structure area 1 and the core tube area 2.

[0060] Figure 3 : Support tyre frame installation; As shown in the figure, the support tyre frame 5 is set just below the hanging column corresponding to the lower hanging layer. The bottom column foot of the support tyre frame 5 is connected to the foundation bottom plate with chemical anchor bolts or embedded bolts that meet the requirements. The support tyre frame adopts the standard section of the finished tower crane or a redesigned structure according to the requirements of the project's in-depth design. In order to ensure the overall stability of the support tyre frame, horizontal steel supports 57 can be set between each auxiliary support tyre frame. A construction operation platform 51, a pre-arch pad 52, a jack 53, a force transmission beam 54, a steel shoulder beam 55 and a steel ladder 56 are set on the top of the support tyre frame.

[0061] Figure 4 :Installation of the lower hanging layer structure; When installing the lower hanging layer structure, the order of installing the first section of the column is elevation re-measurement, setting of pre-arch pads, accurate positioning, verticality adjustment, temporary fixation at the bottom, and stabilization of the wind rope. After installation, the beam components connecting the first section of the column and the surrounding structure should be installed immediately to quickly form a stable system. The column-beam connection nodes in the lower hanging layer structure area should all be hinged.

[0062] Figure 5 :Installation of steel truss layer; the lower hanging layer transfers the load of the lower hanging layer to the steel truss through a number of hanging columns, and then the truss transfers it to the surrounding structure, so the connection nodes of the hanging columns should be constructed strictly according to the design requirements. Most steel truss layers are oversized and overweight components. In the present invention, the steel truss layer should be installed in bulk at high altitude. It is necessary to make reasonable segmentation of the components in advance. Under the premise of meeting the on-site hoisting requirements and transportation capacity, the welding joints should be minimized, and the segmented welding joints should be at the position where the component is less stressed.

[0063] After the steel truss is installed, monitoring points are arranged according to the construction monitoring implementation plan. The main monitoring contents include stress monitoring and vertical deformation monitoring of the main load-bearing components. The monitoring period is from the completion of the truss layer installation to the completion of the concrete pouring of the floor deck. In addition, the support frame also needs to be tested for vertical and horizontal deformation after its installation until the unloading is completed. The construction monitoring system should use an intelligent monitoring system that can remotely collect the stress and deformation data of the main load-bearing components in real time and make timely analysis and decisions.

[0064] Figure 6 : Unloading; Before the unloading activity starts, a comprehensive and detailed inspection must be carried out on the completed lower hanging layer structure area 4, steel structure truss layer 3 and surrounding structure areas. This includes a strict review of the welding quality, confirmation of the fastening of the connectors, and evaluation of the stability of the overall structure. At the same time, ensure that important equipment used for unloading, such as hydraulic jacks, are in good working condition to ensure the smooth progress of the unloading process.

[0065] Before unloading begins, it is necessary to ensure that the monitoring plan has been prepared and approved, the monitoring points have been arranged, and data can be collected normally. In addition, the unloading plan and emergency plan should also be completed and approved. These plans must clearly indicate the order, steps, equipment conditions, safety measures and emergency plan preparation of unloading to ensure the orderly unloading process.

[0066] According to the specific characteristics of the structure and the requirements of the construction plan, the unloading process should adopt the method of hydraulic overall synchronous graded unloading. During the entire unloading process, the principle of "deformation coordination and unloading balance" must be followed to avoid temporary support overload instability due to instantaneous overload of individual support points, or partial damage to the structure as a whole.

[0067] The amount of graded unloading should be scientifically determined based on the analysis software. After each level of unloading is completed, the data at the monitoring point must be kept in mind to ensure the safety and stability of the temporary support and the overall structure. At the same time, sufficient monitoring time should be maintained after each level of unloading, generally not less than 5 hours, until the monitoring data shows stability before the next level of unloading can be carried out. This process will continue until the entire structure is completely separated from the supporting frame and the structural monitoring meets the design requirements.

[0068] After unloading is completed, the supporting cradle and jack should leave a false top. Demolition work can only be carried out after the concrete pouring of the floor decking is completed and the data monitoring shows normal stability.

[0069] Figure 7: Concrete pouring of the lower hanging layer floor slab; after unloading, concrete pouring of each floor of the lower hanging layer structure area 4 begins. In order to minimize the impact of deformation on concrete and facilitate waterproofing, the concrete of the top roof should be poured last. The pouring order of other layers can be formulated according to the specific conditions of the project to ensure the efficiency and safety of the entire construction process.

[0070] Figure 8 : Removal of the supporting tyre frame; the supporting tyre frame is dismantled after the concrete pouring of the floor is completed and the monitoring data is normal. Since the distance between the supporting tyre frame and the lower hanging layer cannot meet the lifting requirements of the crane, a winch is used in conjunction with a pulley block for dismantling operations.

[0071] Fig. 9 : Schematic diagram of the top of the support frame; As shown in the figure, a construction operation platform 51 should be set on the top of the support frame 5 for the safe operation area of ​​the workers during installation related operations. At the same time, the platform will be used in subsequent monitoring, process inspection and unloading. A steel shoulder beam 55 is also set on the top to support the bottom of the force transmission beam 54. Two jacks 53 and a pre-arch pad 52 are set on the upper part of the steel shoulder beam, and hoisted and placed on the top of the pad. Workers support the frame up and down through a steel ladder 56.

[0072] The present invention adopts the method of in-situ installation of the support frame, which has a wide range of project applications, and is particularly suitable for scenarios where the lower hanging area is located on the top plate of the basement and the mechanical position is limited; the core of the in-situ installation method of the support frame is to use a temporary support structure (i.e., the support frame) as an auxiliary to the main structure to achieve in-situ installation and splicing of the steel structure; this method shows significant advantages in terms of saving construction time, safety assurance, and economic rationality. It can not only effectively shorten the project period, but also reduce construction costs while ensuring construction safety, thereby improving social and economic benefits for the enterprise.

[0073] Through precise design and careful construction plan, the in-situ upright installation method of the support frame of the present invention can ensure the safe and accurate installation of large-span under-hanging steel structures while minimizing the impact on the surrounding environment; the successful application of this method not only reflects the technical strength and project management capabilities of the construction team, but also provides valuable experience for similar engineering projects; in modern construction projects, choosing a suitable and efficient construction method is of great significance to improving project quality, saving costs and shortening construction period, and the in-situ upright installation method of the support frame is the ideal choice to meet these requirements.

[0074] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0075] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0076] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0077] The above is a detailed introduction to the in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An in-situ installation method for a large-span steel truss multi-layer under-hanging steel structure, characterized in that: The invention comprises a conventional structure area (1) and a core tube area (2), wherein a truss layer (3) of a steel structure is arranged at the top of the conventional structure area (1) and the core tube area (2), and the truss layer (3) is connected to the lower hanging layer structure area (4) through a sling (7). The lower hanging layer structure area (4) adopts a support frame (5) for in-situ installation sequence construction, and the support frame (5) is arranged from the bottom plate (6) of the structural foundation. After the installation of the lower hanging layer structure area (4) and the truss layer (3) is completed, an intelligent construction monitoring system is arranged. The intelligent construction monitoring system mainly monitors the stress and deformation of the structure when the support frame (5) is unloaded and when the concrete of the floor of the lower hanging layer structure area (4) is poured, so as to ensure the safety of the structural construction; The installation method includes the following specific steps: S1. Foundation verification: Before the support frame (5) is installed, the foundation bearing capacity is carefully verified based on the design drawings and geological survey reports; S11. Construction of the foundation and surrounding structures of the lower hanging layer: If no foundation reinforcement is required after the foundation review, the conventional structure area (1) and the core tube area (2) surrounding the foundation and the lower hanging layer shall be constructed according to the normal procedures; if the foundation of the tire frame area needs to be reinforced, it shall be completed before the foundation construction; S12, deepening of the support frame (5): using computer analysis software to design and verify the support frame (5) according to the upper load before installation, so as to determine the form, material specifications, fixing connection measures and layout of the construction operation platform (51) of the support frame (5); S2. Installation of the support frame (5): Before formal installation, a construction simulation software is used to simulate the lifting, and an analysis is conducted in combination with the actual working conditions and machine positions on site to formulate the best lifting plan; a construction operation platform (51) should be set up on the top of the support frame (5) for steel structure correction, welding operations, subsequent monitoring and unloading work; S21. Acceptance of the support frame (5): After the installation of the support frame (5) is completed, all parties involved in the construction are organized to conduct acceptance of the frame and keep acceptance records; S22, arrangement of monitoring points of the tire frame: after the support tire frame (5) is installed, the vertical and horizontal deformation monitoring points of the tire frame are arranged according to the requirements of the monitoring implementation plan, and each tire frame is arranged with no less than one monitoring point; S3. Installation of the lower hanging layer structure area (4): Before installing the lower hanging layer structure area (4), you must fully understand the design drawings and the construction requirements of key connection nodes. To this end, you need to be familiar with the relevant design drawings and conduct in-depth design to ensure that all details can meet the actual construction requirements; S31. Installation of the first column: The first column should be selected near the surrounding structure of the lower hanging layer. The first column is temporarily fixed at the bottom after lifting, re-measurement of elevation, accurate positioning, and verticality adjustment. Then, the four corners are tightened and stabilized with cables and wind ropes. After that, the beam connected to the column is connected to the surrounding structure. The wind ropes can be removed after a stable system is formed. Subsequent columns and beams are installed in an orderly manner relying on the stable columns and beams. S32, floor deck installation: After the installation of columns and beams on each layer is completed, the steel truss floor decks of each layer below the hanging layer are interspersed. At the same time, to ensure safe construction, when installing the floor deck, the cross operation of column and beam installation should be avoided on the upper part; S4, truss layer (3) installation: The truss layer (3) is installed and constructed by bulk loading in the air; most steel trusses are overweight components, and the selection of lifting equipment and reasonable segmentation of components must be done in combination with the specific project, and the number of welded joints must be reduced while meeting the lifting requirements and transportation capacity; S5. Arrangement of intelligent construction monitoring system: After the installation of the truss layer (3) is completed, the monitoring points are arranged. The monitoring contents include stress monitoring of the main load-bearing components and vertical deformation monitoring. The monitoring period is from the completion of the installation of the truss layer (3) to the completion of the pouring of the floor deck concrete. S6, Unloading: Unloading is carried out by hydraulic overall synchronous graded unloading. During the whole unloading process, the principle of deformation coordination and unloading balance must be followed to avoid temporary support overload instability or partial overall damage to the structure due to instantaneous overload of individual support points; S7, pouring of floor slab concrete: after unloading, start pouring concrete for each floor of the lower hanging layer; in order to minimize the impact of deformation on concrete and facilitate waterproofing, the concrete of the top roof should be poured last; the pouring order of other layers can be formulated according to the specific conditions of the project to ensure the efficiency and safety of the entire construction process; S8, dismantling of the support frame (5): the support frame (5) is dismantled after the pouring of floor concrete is completed and the monitoring data is normal; S9. Acceptance: After each process is completed and relevant tests are passed, acceptance will be organized according to the acceptance specifications.

2. The in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure according to claim 1 is characterized by: In S1, the load value during foundation verification should include the deadweight of the cradle, the deadweight of the structure above the cradle, possible wind loads, and temporary loads generated during construction; if the verified foundation load cannot meet the requirements, appropriate foundation reinforcement measures should be taken in consultation with the design team.

3. The in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure according to claim 1 is characterized by: In the above S22, the initial monitoring data is measured and recorded after the tire frame is installed, and the monitoring is stopped until the unloading is completed, and the monitoring is performed every 3 to 5 days.

4. The in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure according to claim 1 is characterized by: In the above-mentioned S3, after the detailed design is completed, the drawings shall be submitted to the original design unit for review and confirmation; only after obtaining the approval of the design unit can the components be processed and implemented according to these drawings to ensure the construction quality and the complete realization of the design intent; when installing the first-floor columns, a pad with a thickness corresponding to the designed arch value shall be set at the bottom of the columns that need to be pre-arched.

5. The in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure according to claim 1 is characterized by: In the above S32, after installing the floor decking of the lower hanging layer, in order to ensure that the force system can be normally converted after unloading, the pouring of floor concrete should be temporarily shelved and carried out after the structure is unloaded; this can ensure the stability of the structure during loading and unloading, and avoid affecting the force performance and safety of the structure due to premature pouring of concrete.

6. The in-situ installation method of a large-span steel truss multi-layer under-hanging steel structure according to claim 1 is characterized by: In the above-mentioned S5, the construction monitoring system adopts an intelligent monitoring system, which can remotely collect stress and deformation data of the main load-bearing components in real time and make analysis and decisions in time.

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