Large-span steel truss tire-free frame sliding installation method

Abstract

The application provides a large-span steel truss free jig slip installation method, which is characterized in that: in the meanwhile of deepening the design of the steel structure, the structural form, installation method and the like of the large-span steel truss structure are modeled, deduced and analyzed to determine a reasonable slip working condition, the arch truss span and truss member arrangement are preliminarily determined according to the deduction result; the standardization and the type of the arch truss are determined according to the calculation result; after the installation of the arch truss is completed, the lower hanging slip track is installed, and the pre-arching value is determined according to the truss corridor hoisting deduction and deformation calculation to adjust the track elevation; after the installation of the arch truss, the slip track, the steel truss assembly and the slip platform is completed, the steel truss assembly slips; after the steel truss structure is slipped into position, the arch truss is removed in sections, and the subsequent construction can be continued. The application solves the problem that the conventional hoisting mode cannot meet the installation requirement of the large-span steel truss under the condition that the jig cannot be set at the lower part or the heavy load crane cannot be erected during the hoisting process of the large-span steel truss structure under the specific working condition.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and in particular relates to a method for sliding installation of large-span steel truss frames without a frame. Background Technology

[0002] With the advancement of urban construction, an increasing number of building projects are designed with a shared concept of integration and interconnection, connecting the various buildings of the proposed project through sky bridges. These sky bridges for inter-building communication typically use steel trusses, and these steel bridges often have large spans, some even crossing roads or rivers. The hoisting of these large-span steel truss sky bridges during construction is inherently challenging. For special working conditions such as crossing roads, rivers, or subway lines where it is impossible to erect heavy-duty cranes or set up temporary support structures, the hoisting of large-span steel structure sky bridges is a major construction difficulty in such projects. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for the sliding installation of large-span steel trusses without the need for a formwork frame. By utilizing standardized arch truss components and steel cables to form a support system, the steel truss is assembled through sliding, avoiding the need for a formwork frame at the bottom of the hoisted components in traditional sliding processes. This method solves some construction problems under specific working conditions to a certain extent.

[0004] The present invention achieves the above-mentioned technical objectives through the following technical means.

[0005] A method for sliding installation of a large-span steel truss frame without a scaffold includes the following steps:

[0006] Step 1: Detail the design and initially determine the selection of standardized arch trusses, the segment lengths of large-span steel trusses, and the segment locations;

[0007] Step 2: By establishing a model, the construction of large-span steel structures is globally simulated, and the most unfavorable load combination throughout the entire working life cycle of the steel truss is summarized.

[0008] Step 3: Recalculate the deformation of the arch truss, adjust the selection, calculate the pre-arch height of the sliding track to meet the installation and use requirements of the large-span steel truss, and determine the final sliding scheme and equipment selection;

[0009] Step 4: Construct column piers or foundations according to on-site hoisting requirements, and reserve arch truss foundation section connectors or corbels on the column piers or foundations;

[0010] Step 5: Install the arch truss and sliding equipment;

[0011] Step 6: After the arch truss is hoisted, erect the assembly and sliding platform;

[0012] Step 7: Sliding construction of the steel truss;

[0013] Step 8: Removal of the arch truss.

[0014] Further, the specific process of step 5 is as follows: First, install the arch truss foundation section on the basis of both ends of the span, which is used for the angle conversion between the standard section and the foundation section plane. Then, hoist the arch truss standard section. The standard sections of the set have the same curvature but different spans. The standard sections are connected in pairs. The appropriate selection is made according to the span requirements. After all the skeletons of the standard sections are hoisted, the secondary members are installed. Then, the lower steel cable, track support and channel steel sliding track are set on the arch truss according to the design conditions.

[0015] Furthermore, the foundation section consists of two short steel trusses and a hinge with a pin. One end of one short steel truss is connected to the hinge, and the other end is welded with an end plate connected to the foundation. One end of the other short steel truss is connected to the hinge, and the other end is connected to the standard section. The angle between the two steel trusses is adjusted and fixed by the hinge with a pin.

[0016] Furthermore, the standard section consists of detachable upper and lower chords and web members, which are connected by bolts. In actual construction projects, appropriate members are selected and assembled according to the requirements of different working conditions such as span and load.

[0017] Furthermore, during the installation of the arch truss, the upper and lower chords and main load-bearing web members of the arch truss are installed first. After the main frame is installed, the secondary web members and secondary components are installed. When a single arch truss is used, the secondary web members between the upper and lower chords are installed again after the main frame is installed. When multiple arch trusses are used, the connecting members or temporary support components between the multiple trusses need to be installed again after the main frame is installed.

[0018] Furthermore, the track support includes multiple sets of L-shaped I-beam supports. The lower ends of the two L-shaped I-beam supports in each set are connected by L-shaped I-beam connecting rods and bolts. The top of the two L-shaped I-beam supports in each set is connected to a hanging steel cable, and the other end of the hanging steel cable is connected to the arch truss. Transverse track I-beam supports are connected to the sides of the L-shaped I-beam supports and the sides of adjacent sets of L-shaped I-beam supports. The track I-beam supports between the sides of adjacent sets of L-shaped I-beam supports are connected by connecting end plates. Connecting rods are connected to the lower surface of the L-shaped I-beam supports. Track I-beam diagonal braces are connected between the track I-beam supports and the connecting rods. Two channel steel sliding tracks are installed between the upper surfaces of adjacent sets of L-shaped I-beam supports. Sliding trolleys and jacks are installed in the channel steel sliding tracks.

[0019] Furthermore, the assembly and sliding platform is connected to the sliding track and the foundation. The part connected to the foundation is equipped with a segmented steel truss limiter and a jack, which are used for limiting and fixing the slidable steel truss and for power supply during the jacking and sliding process.

[0020] Furthermore, the specific process of the steel truss sliding construction is as follows: the assembled segmented steel truss is placed on a sliding trolley, which is equipped with jacks. After sliding into place, the elevation of the large-span steel truss is adjusted according to the actual site conditions. The construction procedure is to slide simultaneously from both ends of the span and push from both ends towards the middle. The large-span steel truss is pushed by a traction steel cable, and a jack is provided at the end to provide the pushing force. At the same time, a limiting device is provided at the end to prevent the slidable part from shifting or deforming before the next large-span steel truss segment slides.

[0021] The present invention has the following beneficial effects:

[0022] This invention solves the problem of construction difficulties in special working conditions such as the inability to support the lower part of a large-span steel structure or the limitation of load by using an arch truss to erect a sliding track for the sliding installation of the steel truss. This invention eliminates the need for a support frame at the bottom of a large-span steel truss structure during hoisting by using standardized and modular arch truss components and steel cables, thus meeting the special construction requirements in specific working conditions where a support frame or heavy-duty crane cannot be erected at the bottom of a large-span steel structure.

[0023] This invention sets the arch truss as a standardized and modular structure, that is, it is divided into standard sections and foundation sections to adapt to different lifting weights, different spans, and different working conditions. The equipment model can be reasonably selected according to construction needs, and the span requirements can be met by assembling single or multiple sections. At the same time, the detachable structural frame and secondary members can be disassembled or added according to the lifting requirements, making the solution more economical and reasonable. The standardized and modular arch truss can be reused multiple times.

[0024] This invention combines data modeling, finite element analysis and other technologies to simulate the entire life cycle of the construction process, reveal potential risk points in advance, and reduce the frequency of various emergencies during construction. It also uses sliding tracks to reduce the cumulative error caused by the segmented installation of large-span steel structures during construction, which is beneficial for the elevation control and accuracy correction of large-span structures.

[0025] Traditional large-span steel truss structures require pre-lifting during installation to offset cumulative deflection. Since the sliding track of this invention is a flexible structure, the pre-lifting height of the large-span steel truss and sliding track during installation needs to be recalculated. At the same time, the sliding tank is equipped with jacks, which can adjust the elevation of the steel truss erection point in real time according to the monitoring situation. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the large-span steel truss structure described in this invention;

[0027] Figure 2 This is a schematic diagram of the basic section described in this invention;

[0028] Figure 3 This is a schematic diagram of the truss sliding operation described in this invention;

[0029] Figure 4 This is a transverse view of the sliding track described in this invention;

[0030] Figure 5 This is a longitudinal view of the sliding track described in this invention.

[0031] In the diagram: 1-L-type I-beam support; 2-L-type I-beam connecting rod; 3-Underhanging steel cable; 4-Railway I-beam support; 5-Railway I-beam diagonal brace; 6-Connecting end plate; 7-Channel steel sliding track; 8-Foundation; 9-Large span steel truss; 10-Assembly and sliding platform; 11-Arch truss. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0033] The large-span steel truss frame sliding installation method of the present invention includes the following process:

[0034] Step 1: Detailed Design: Based on the construction drawings of the large-span steel truss, the large-span steel truss is segmented according to the hoisting and sliding requirements. The nodes between each component are further designed in detail, and the stress, deformation, and hoisting load of each component are calculated. Based on the existing calculation results, the selection of standardized arch truss 11, the segment length of the large-span steel truss 9, and the segment position are preliminarily determined. Each steel truss segment is coded. During the assembly process, the mixing of components affects the overall construction requirements during the sliding installation process. In addition, the requirements of later hoisting and sliding processes are considered in advance. In addition to the conventional detailed design node connections, lifting lugs or temporary reinforcement components are arranged in the detailed design stage.

[0035] Step 2: Modeling and simulation: Based on the available construction equipment and on-site working conditions, the size of the 9-section hoisting of the large-span steel truss, and the single-section lifting weight, a model is established to simulate the construction of the large-span steel structure globally, preliminarily determine the key difficulties in the entire construction life cycle, analyze the load changes and deformation at each stage of the steel truss sliding construction, and summarize the most unfavorable load combination for the entire working life cycle of the steel truss.

[0036] Step 3: Deformation verification and selection: Based on the most unfavorable load combination, recalculate the deformation of the arch truss 11, and adjust the selection accordingly. Based on the results of stress analysis and deformation calculation, determine whether to select one or more standardized arch trusses 11, the specifications and arrangement of the chords and web members, etc., to meet the load-bearing capacity and deformation verification. Prioritize standardized arch trusses 11 that are easy to hoist, meet the load-bearing capacity requirements, and have small deformation to meet the construction needs under special working conditions. Calculate the pre-arch height of the sliding track to meet the installation and use requirements of the large-span steel truss 9. Finally, determine the final scheme for steel structure sliding and the selection of equipment and facilities.

[0037] Step 4: Construction Preparation: Arch truss 11 and large-span steel truss 9 structures as follows Figure 1 As shown, before construction, the column piers or foundations 8 are constructed according to the on-site hoisting requirements. Arch truss foundation section connectors or corbels are reserved on the column piers or foundations 8 for subsequent installation and fixing of the arch truss 11. Subsequent construction can only be carried out after the strength of the column piers or foundations 8 reaches the design requirements.

[0038] Step 5: Installation of arch truss 11 and sliding equipment: Refer to Figure 2 First, install the foundation sections of the arch truss 11 on the foundations 8 at both ends of the span to convert the angle between the standard section and the plane of the foundation 8. Then, hoist the standard sections of the arch truss 11. The standard sections of the set have the same curvature but different spans. The standard sections are connected in pairs and selected appropriately according to the span requirements. After all the skeletons of the standard sections are hoisted, the arch truss 11 has a certain rigidity. Then, the secondary members are installed. After all the web members and connecting members between the trusses are installed, the lower steel cable 3, track support, and channel steel sliding track 7 are set on the arch truss 11 according to the design conditions, and the elevation of the sliding track is adjusted according to the verification results.

[0039] The foundation section consists of two short steel trusses and a hinge with a pin. One end of one short steel truss is connected to the hinge, and the other end is welded with an end plate and connected to the foundation 8. The other short steel truss is connected to the hinge at one end and to the standard section at the other end. The angle between the two steel trusses can be adjusted and fixed by the hinge with a pin.

[0040] The standard section consists of detachable upper and lower chords and web members. The upper and lower chords and web members are connected by bolts. Appropriate members can be selected for assembly according to the requirements of different working conditions such as span and load. The arch truss 11 consists of a maximum of 2 to 3 standard sections. If there are too many standard sections, the installation of the arch truss 11 itself will be quite difficult.

[0041] Because standardized and prefabricated arch truss sections are used, the upper and lower chords and main load-bearing web members of the arch truss 11 can be installed first to reduce the lifting weight during the hoisting process. After the main frame is installed, the secondary web members and secondary components are then installed. After the arch truss 11 frame is installed, it already has a certain rigidity and can stand stably on its own without the help of other supporting structures. When a single arch truss 11 is used, only the secondary web members between the upper and lower chords need to be installed again. When multiple arch trusses 11 are used, the connecting members or temporary support components between the multiple trusses need to be installed again.

[0042] Among them, reference Figure 4 , 5 The track support includes multiple sets of L-shaped I-beam supports 1. The lower ends of the two L-shaped I-beam supports 1 in each set are connected by L-shaped I-beam connecting rods 2 and bolts. The top of the two L-shaped I-beam supports 1 in each set is connected to a hanging steel cable 3, and the other end of the hanging steel cable 3 is connected to the arch truss 11. The sides of the L-shaped I-beam supports 1 and the sides of the adjacent sets of L-shaped I-beam supports 1 are connected by track I-beam supports 4. The track I-beam supports 4 between the sides of the adjacent sets of L-shaped I-beam supports 1 are connected by connecting end plates 6. The lower surface of the L-shaped I-beam supports 1 is connected to connecting rods. The track I-beam supports 4 and the connecting rods are connected by track I-beam diagonal braces 5. Two channel steel sliding tracks 7 are installed between the upper surfaces of the adjacent sets of L-shaped I-beam supports 1. The channel steel sliding tracks 7 are equipped with sliding trolleys and jacks.

[0043] Step 6: Assembly and Sliding Platform 10 Installation: After the arch truss 11 frame is hoisted, the assembly and sliding platform 10 can be erected. The platform is connected to the sliding track and foundation 8. The part connected to the foundation 8 is equipped with segmented steel truss limiters and jacks for limiting and fixing the slidable steel truss and providing power for the jacking and sliding process. The platform is designed to meet the requirements of assembling and sliding the largest steel truss section. It can take the form of a ground support frame or a steel platform. The assembly platform is connected to the sliding track, and jacking jacks and limiters are installed at the connection. After the segmented steel truss is assembled, it is jacked and slid. After sliding into place, the next steel truss section is hoisted onto the platform.

[0044] Step 7: Sliding construction of large-span steel truss 9: Refer to Figure 3 The assembled segmented large-span steel truss 9 is placed on a sliding trolley equipped with jacks. After sliding into place, the elevation of the large-span steel truss 9 can be adjusted according to the actual site conditions. The construction sequence can be arranged to slide simultaneously from both ends of the span and advance from both ends to the middle to save construction time. The large-span steel truss 9 has a traction steel cable in the jacking direction, and jacks at the end provide jacking force. At the same time, a limit device is installed at the end to prevent the slidable part from shifting or deforming before the next segment of the large-span steel truss 9 slides.

[0045] Step 8: Dismantling of Arch Truss 11: After the hoisting of the large-span steel truss 9 is completed, the arch truss 11 is dismantled in accordance with the principle of "supporting first and dismantling later, supporting later and dismantling first", thus completing the installation of all large-span steel structures.

Claims

1. A method for sliding installation of a large-span steel truss without a frame, characterized in that, The process includes the following: Step 1: Detail the design and initially determine the selection of standardized arch trusses, the segment lengths of large-span steel trusses, and the segment locations; Step 2: By establishing a model, the construction of large-span steel structures is globally simulated, and the most unfavorable load combination throughout the entire working life cycle of the steel truss is summarized. Step 3: Recalculate the deformation of the arch truss, adjust the selection, calculate the pre-arch height of the sliding track to meet the installation and use requirements of the large-span steel truss, and determine the final sliding scheme and equipment selection; Step 4: Construct the column piers or foundations (8) according to the on-site hoisting requirements, and reserve arch truss foundation section connectors or corbels on the column piers or foundations (8); Step 5: Install the arch truss and sliding equipment; The specific process of step 5 is as follows: First, install the arch truss foundation section on the foundation (8) at both ends of the span, which is used for the angle conversion between the subsequent arch truss standard section and the foundation (8) plane; then hoist the arch truss standard section. The standard sections of the set have the same curvature and different spans. The standard sections are connected in pairs. Select them appropriately according to the span requirements. After all the skeletons of the standard section are hoisted, the secondary members are installed. Then, the lower steel cable (3), track support, and channel steel sliding track (7) are set on the arch truss according to the design conditions. The standard section consists of detachable upper and lower chords and web members. The upper and lower chords and web members are connected by bolts. In actual construction projects, the appropriate members are selected and assembled according to the requirements of different working conditions such as span and load. During the installation of the arch truss, the upper and lower chords and main load-bearing web members of the arch truss are installed first. After the main frame is installed, the secondary web members and secondary components are installed. When a single arch truss is used, the secondary web members between the upper and lower chords are installed again after the main frame is installed. When multiple arch trusses are used, the connecting members or temporary support components between the multiple trusses need to be installed again after the main frame is installed. Step 6: After the arch truss is hoisted, erect the assembly and sliding platform (10); Step 7: Sliding construction of the steel truss; Step 8: Removal of the arch truss.

2. The method for sliding installation of large-span steel truss frames without a frame according to claim 1, characterized in that, The foundation section consists of two short steel trusses and a hinge with a pin. One end of one short steel truss is connected to the hinge, and the other end is welded with an end plate connected to the foundation (8). The other short steel truss is connected to the hinge at one end and to the standard section at the other end. The angle between the two steel trusses is adjusted and fixed by the hinge with a pin.

3. The method for sliding installation of large-span steel truss frames without a skid plate according to claim 1, characterized in that, The track support includes multiple sets of L-shaped I-beam supports (1). The lower ends of the two L-shaped I-beam supports (1) in each set are connected by L-shaped I-beam connecting rods (2) and bolts. The top of the two L-shaped I-beam supports (1) in each set is connected to a hanging steel cable (3), and the other end of the hanging steel cable (3) is connected to the arch truss. The sides of the L-shaped I-beam supports (1) and the sides of the L-shaped I-beam supports (1) in adjacent sets are all connected by transverse track I-beam supports (4). The track I-beam supports (4) between the sides of the adjacent L-shaped I-beam supports (1) are connected by connecting end plates (6); the lower surface of the L-shaped I-beam supports (1) is connected with connecting rods, and the track I-beam supports (4) and the connecting rods are connected with track I-beam diagonal braces (5); two channel steel sliding rails (7) are installed between the upper surfaces of the adjacent L-shaped I-beam supports (1), and a sliding trolley and a jack are installed in the channel steel sliding rails (7).

4. The method for sliding installation of large-span steel truss frames without a frame according to claim 3, characterized in that, The assembly and sliding platform (10) is connected to the sliding track and the foundation (8). The part connected to the foundation (8) is equipped with a segmented steel truss limiter and a jack, which are used for limiting and fixing the slidable steel truss and for power supply during the jacking and sliding process.

5. The method for sliding installation of large-span steel truss frames without a skid plate according to claim 3, characterized in that, The specific process of the steel truss sliding construction is as follows: the assembled segmented steel truss is placed on the sliding trolley, which is equipped with jacks. After sliding into place, the elevation of the large-span steel truss (9) is adjusted according to the actual site conditions. The construction procedure is to slide from both ends of the span simultaneously and push from both ends to the middle. The large-span steel truss (9) has traction steel cables in the jacking direction, and jacks at the end provide jacking force. At the same time, a limiting device is provided at the end to prevent the completed sliding part from shifting or deforming before the next large-span steel truss (9) slides.

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