Overall system conversion process after accumulative slippage of space pipe truss

Abstract

The invention relates to an overall system conversion process after accumulative slippage of a space pipe truss, and relates to the technical field of steel structure construction. According to the process, a supporting bracket and a jack system are installed, and a mode of combining graded unloading and lateral pushing is adopted, so that accurate conversion of a truss from a temporary supporting state to a design position is achieved. The method comprises the key steps of step-by-step unloading with 20 mm as a circulation unit, jack bottom supporting height adjustment, hydraulic synchronous control and lateral limiting measures. The method solves the problems of poor synchronism, stress concentration and the like in a traditional unloading method, has the advantages of high in-place precision, high in safety, high in construction efficiency and the like, and is suitable for construction of a large-span space pipe truss structure.

Description

Technical Field

[0001] This invention relates to the field of construction technology for large-span spatial steel structures, and in particular to a process for converting a spatial truss into an overall system after cumulative sliding. This process is applicable to the installation and unloading of large-span spatial truss structures such as stadiums, airport terminals, and exhibition centers. Specifically, it addresses the overall system conversion process for truss structures constructed using the cumulative sliding method, involving temporary support unloading, structural positioning, and support installation after sliding is completed. Background Technology

[0002] Spatial truss structures are widely used in large-span buildings due to their lightweight, high strength, and aesthetically pleasing design. Traditional construction methods include in-situ installation and sliding methods, with the cumulative sliding method achieving efficient construction through segmented assembly and gradual sliding. However, the system transformation after sliding (i.e., unloading of temporary supports and structural positioning) is a critical challenge in construction; improper handling can easily lead to structural deformation, stress concentration, or even safety accidents.

[0003] In existing technologies, truss unloading often involves directly removing supports or simple staged unloading, which has the following problems: Poor synchronization during unloading: Traditional methods lack a precise synchronization control system, leading to asynchronous unloading at various support points and causing local stress exceeding limits in the structure. For example, in some projects, asynchronous jack movements cause local stress in the truss to exceed the material's yield strength, resulting in deformation.

[0004] Insufficient positioning accuracy: Inadequate limiting measures often result in truss positioning deviations exceeding 20mm, affecting subsequent support welding and quality acceptance. Deviation control is particularly difficult at complex nodes (such as ball joint supports).

[0005] Inaccurate stress control: The lack of real-time stress monitoring during unloading makes it impossible to effectively control stress changes, easily leading to crack formation. Data shows that stress fluctuations using traditional methods can reach over 30% of the design value.

[0006] Incoordination in process flow: The sliding construction and system conversion processes are disconnected, and there are operational gaps between the removal of temporary supports and the installation of permanent supports, increasing safety risks.

[0007] A search revealed existing patents, such as CN120556743A, which relates to a cumulative sliding construction process for large-span spatial tubular truss structures. This process falls under the technical field of tubular truss construction. It involves installing sliding tracks for the cumulative sliding construction of large-span spatial tubular truss structures; sliding and folding the trusses of the large-span spatial tubular truss structure; opening temporary connections after the trusses have slid and folded to unfold each sliding truss; and replacing supports and removing the tracks. This improves the construction efficiency of large-span spatial tubular truss construction, enhances recyclability, and improves the versatility and reliability of the hydraulic jacking equipment used in the construction. It effectively avoids the shortcomings of existing technologies for large-span spatial tubular truss construction, such as low construction efficiency, insufficient recyclability, and insufficient versatility and reliability of the hydraulic jacking equipment. It only focuses on the sliding process itself, and only briefly mentions the unloading steps for the system transformation after sliding without providing a system solution. It does not involve the synchronous control of unloading after sliding, nor does it provide specific processes for the transformation of the space truss system, nor does it provide a hierarchical control strategy.

[0008] Therefore, there is an urgent need in this field for a safe, accurate, and efficient system conversion process to solve key technical problems such as synchronization, accuracy, and stress control. Summary of the Invention

[0009] To address the shortcomings of existing technologies, the purpose of this invention is to provide a process for converting a space truss system after cumulative sliding, solving problems such as asynchronous unloading, large positioning deviations, and difficulty in stress control in existing technologies. This invention provides a process for converting a space truss system after cumulative sliding with high synchronization, controllable stress, and precise positioning. This process achieves a safe and precise conversion of the truss from a temporary support state to its designed position through a combination of measures including staged unloading, synchronous control, and lateral jacking.

[0010] The above-mentioned objective of this invention is achieved through the following technical solutions: This invention provides a process for converting a space truss into its overall system after cumulative sliding, comprising the following steps: Step 1, installing support brackets and jack systems at the truss supports; Step 2, converting the truss from a temporary support state to its design position through a staged unloading method; Step 3, adjusting the truss into position using lateral jacking measures; Step 4, synchronously controlling displacement and stress during the unloading process.

[0011] According to one embodiment of the present invention, the supporting bracket is a box-shaped structure with a cross-sectional dimension of 300mm×160mm×30mm×20mm, made of Q355B steel, and welded to the support ball and truss chord.

[0012] According to one embodiment of the present invention, the jack system includes multiple 100t screw jacks, with two jacks arranged at each support, and the bottom of the jacks is supported by a φ168mm×8mm round tube.

[0013] According to one embodiment of the present invention, the graded unloading includes lowering the truss in five steps with a cycle unit of 20mm. After each step of lowering, a φ168mm×8mm steel pipe is used as a temporary support, and the bottom support height of the jack is adjusted.

[0014] According to one embodiment of the present invention, the bottom support height of the jack in the staged unloading is 277mm, 177mm and 77mm respectively, and finally descends to the design elevation.

[0015] According to one embodiment of the present invention, the lateral jacking is carried out using a 100t hydraulic jack, which is used to jack the truss along the span to the design position, and then the fixed support is welded after jacking.

[0016] According to one embodiment of the present invention, the synchronization control is achieved through a hydraulic system, the displacement synchronization deviation is controlled within ±2mm, and the stress is ensured not to exceed the design value through real-time monitoring.

[0017] According to one embodiment of the present invention, it further includes lateral limiting measures, wherein the A-axis adopts a 160mm×160mm×20mm×20mm housing, and the Q-axis adopts a 260mm×160mm×20mm×20mm housing, which are welded to the foundation embedded parts.

[0018] According to one embodiment of the present invention, stress monitoring is performed on key nodes during the unloading process, and post-heat welding process is used to control the weld quality.

[0019] According to one embodiment of the present invention, the process is applicable to space truss structures installed using the cumulative sliding method, wherein the center deviation of the support after the truss is in place is not greater than 10 mm, and the verticality is not greater than h / 250 and not greater than 15 mm.

[0020] In summary, compared with the prior art, the present invention has at least one of the following beneficial technical effects: 1. High Synchronization: The hydraulic synchronization control system enables multiple jacks to work in tandem, with displacement deviation controlled within ±2mm, effectively avoiding stress concentration problems caused by asynchrony. Traditional methods typically result in synchronization deviations of 5-10mm.

[0021] 2. Precise positioning: Combining staged unloading and lateral jacking measures, the truss positioning deviation is ≤10mm, far lower than the 20-30mm deviation of traditional methods. The design of the limiting box and supporting brackets improves the positioning accuracy.

[0022] 3. High safety: The staged unloading strategy ensures a smooth transition of structural stress, and stress monitoring ensures that the maximum compressive stress is ≤262.5MPa (verified based on calculations), which is lower than the yield strength of Q355 steel (345MPa). The temporary support system provides multiple layers of protection.

[0023] 4. Efficiency Improvement: The system conversion process is seamlessly integrated with the sliding construction, shortening the overall construction period by approximately 20%. Taking a 145m span project as an example, traditional unloading takes 7-10 days, while this invention only takes 5-7 days.

[0024] 5. Wide adaptability: Applicable to space tubular truss structures with various spans (70-162m) and support conditions, especially for the conversion control of complex nodes (such as ball joint supports). Attached Figure Description

[0025] Figure 1 This is a flowchart of the present invention.

[0026] Figure 2 This is a schematic diagram of the arrangement of the support bracket and jack of the present invention (showing the connection method between the box-type support bracket (300mm×160mm×30mm×20mm) and the truss support, as well as the arrangement position of the 100t screw jack).

[0027] Figure 3 This is an elevation view of the A-axis limiting measure of the present invention (showing the connection details between the 160mm×160mm×20mm×20mm limiting box and the foundation back beam, including welding method and dimension markings).

[0028] Figure 4 This is a plan view of the A-axis limiting measure of the present invention (showing the connection details between the 160mm×160mm×20mm×20mm limiting box and the foundation back beam, including welding method and dimension markings).

[0029] Figure 5 This is an elevation view of the Q-axis limiting measure of the present invention (showing the connection details between the 260mm×160mm×20mm×20mm box and the concrete column, including the welding method and dimension markings).

[0030] Figure 6 This is a plan view of the Q-axis limiting measure of the present invention (showing the connection details between the 260mm×160mm×20mm×20mm box and the concrete column, including the welding method and dimension markings). Detailed Implementation

[0031] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0032] In the description of this application, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" 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 an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0034] Example 1: Reference Figure 1 The present invention discloses a process for converting a space truss into an overall system after cumulative sliding, comprising the following steps: Step 1, installing support brackets and jack systems at the truss supports; Step 2, converting the truss from a temporary support state to the design position through a staged unloading method; Step 3, adjusting the truss into position using lateral jacking measures; Step 4, synchronously controlling the displacement and stress during the unloading process.

[0035] In this embodiment, the conversion process specifically includes the following steps: 1. Preliminary preparation and inspection: Check the integrity of the sliding track and temporary support system to confirm that the truss is in a stable state.

[0036] Install the support bracket system: Weld box-type support brackets at the truss supports, refer to... Figure 2 The cross-sectional dimensions are 300mm×160mm×30mm×20mm, and the material is Q355B steel. Each bracket is equipped with two 100t screw jacks, and the bottom of the jacks is supported by φ168mm×8mm round pipes. The support height is adjusted according to the unloading stage.

[0037] Lateral limiting measures are implemented: A 160mm×160mm×20mm×20mm box-shaped structure is welded to the foundation embedded parts on the A-axis side; a 260mm×160mm×20mm×20mm box-shaped structure is used on the Q-axis side. The limiting box-shaped structure is close to the foundation back beam, and its bottom is welded and fixed to the embedded parts.

[0038] Verify the hydraulic synchronization control system to ensure that the synchronization accuracy of the jack's movements is within ±2mm.

[0039] 2. Tiered unloading process: Step 1: Unloading: Simultaneously lift all jacks to slightly raise the truss (approximately 5mm), releasing the wedges from contact with the rails. Then remove the wedges and sliding rails, allowing the truss weight to be fully borne by the jacks.

[0040] The second step of unloading: Lower the truss by 100mm in 20mm increments. During the descent, insert a φ168mm×8mm steel pipe at the bottom of the support as a temporary support. Then remove the jacks, adjust the height of the bottom support steel pipe to 277mm, and reposition the jacks.

[0041] Step 3: Unloading: Repeat the descent cycle, then descend another 100mm, and replace the bottom support steel pipe to a height of 177mm.

[0042] Step 4: Unloading: Continue to lower by 100mm and replace the support steel pipe to a height of 77mm.

[0043] Step 5: Unloading: Finally, lower the vehicle to the design elevation and install the permanent limit device. (Refer to...) Figure 3 and Figure 4 A 160mm×120mm×20mm×20mm limit box is installed at the bottom of the A-axis support, refer to Figure 5 and Figure 6 The Q-axis support is welded and fixed according to the design.

[0044] The entire unloading process is synchronously controlled via a hydraulic system, with the displacement deviation of each jack controlled within ±2mm. After each unloading step, a 10-15 minute pause is performed for stress monitoring to ensure that the structural stress is within a safe range (maximum compressive stress ≤295MPa).

[0045] 3. Lateral pushing into place: A 100t hydraulic jack is placed on axis A to apply a jacking force along the span of the truss, precisely pushing the truss to the design position.

[0046] During the jacking process, the truss displacement and support reaction force are monitored in real time, and the jacking speed is controlled within 5 mm / min to ensure that the positioning deviation is no more than 10 mm.

[0047] Once in place, the fixed supports are welded immediately to complete the structural system conversion.

[0048] 4. Synchronous control and monitoring: A hydraulic synchronization control system is adopted, including power control, sensor detection, and computer control modules. The system monitors the displacement and pressure data of each jack in real time and adjusts the hydraulic cylinder action through a PID algorithm to ensure synchronization accuracy.

[0049] Set up stress monitoring points: attach strain gauges at key nodes (such as supports and rod connections) to monitor stress changes during unloading and ensure that the maximum stress does not exceed 85% of the material's design strength (i.e., the stress of Q355 steel is controlled within 250MPa).

[0050] Deformation monitoring: Use a total station to monitor truss deflection and lateral displacement, and control the verticality deviation within h / 250 (h is the truss height) and not more than 15mm.

[0051] 5. Quality Acceptance and Follow-up Processing: Inspect the quality of the support welds and perform non-destructive testing (ultrasonic or radiographic testing) to ensure that the weld grade meets the first-class standard.

[0052] Measure the center deviation of the support (≤10mm), the verticality of the truss (≤h / 250), and the overall elevation deviation (±15mm).

[0053] Dismantle temporary facilities, including jacks and support brackets, to complete the system conversion.

[0054] The supporting bracket is a box-shaped structure with a cross-sectional dimension of 300mm×160mm×30mm×20mm, made of Q355B steel, and welded to the support ball and truss chord. The jack system includes multiple 100t screw jacks, with two jacks arranged at each support. The bottom of the jacks is supported by φ168mm×8mm round tubes.

[0055] The staged unloading process involves lowering the truss in five steps, with each step in 20mm increments. After each step, a φ168mm×8mm steel pipe is used as a temporary support, and the bottom support height of the jacks is adjusted. During the staged unloading, the bottom support heights of the jacks are 277mm, 177mm, and 77mm respectively, ultimately lowering the truss to the design elevation. Lateral jacking is performed using 100t hydraulic jacks, pushing the truss along its span to the design position, and then welding fixed supports after jacking.

[0056] Synchronization control is achieved through a hydraulic system, with displacement synchronization deviation controlled within ±2mm. Stress is monitored in real time to ensure it does not exceed the design value. Lateral limiting measures are also included, see reference... Figure 3 and Figure 4 The A-axis uses a 160mm×160mm×20mm×20mm housing, refer to... Figure 5 and Figure 6 The Q-axis uses a 260mm×160mm×20mm×20mm housing, which is welded to the foundation embedded parts.

[0057] Stress monitoring was conducted at key nodes during unloading, and post-heat welding was used to control weld quality. The process is applicable to space truss structures installed using the cumulative sliding method, where the center deviation of the support after the truss is in place is no greater than 10mm, and the verticality is no greater than h / 250 and no greater than 15mm.

[0058] In this embodiment, a 145m span enclosed material shed truss system is used as an example.

[0059] Project Overview: The truss axis dimensions are 145m × 103.5m, with a single truss weighing 155t, and it is installed in 3 sections. The cumulative sliding method is used to install trusses from axes 37 to 54, while trusses from axes 1 to 18 and 55 to 72 are installed in situ. The truss supports are spherical hinge supports, and the design elevation is +22.09m.

[0060] Before system conversion: After the sliding is completed, the truss is supported by temporary sliding tracks and wedges, and needs to be converted to permanent supports.

[0061] System conversion steps: 1. Preparation (takes 4 hours): Inspect the support system: Confirm that the sliding rail is free from deformation and the wedges are tightened. Use a torque wrench to check the bolt connections; the torque value should meet the design requirement of 350 N·m.

[0062] Install support brackets: Weld box-type brackets (300mm×160mm×30mm×20mm, Q355B) to each support on the A and Q axes. The brackets and support ball joints are bevel welded with a weld height of 20mm and subjected to 100% ultrasonic testing.

[0063] Install jacks: Install two 100t screw jacks on each bracket, with a φ168mm×8mm round pipe (initial height 277mm) at the bottom. Connect the jacks to the hydraulic pump station, and set the pump station pressure to 70MPa.

[0064] Setting up limiting devices: Weld a 160mm×160mm×20mm×20mm limiting box to the A-axis side and weld it to the foundation embedded parts; weld a 260mm×160mm×20mm×20mm box to the Q-axis side.

[0065] Validate the synchronization system: Start the hydraulic control system and test the synchronous movement of the jacks. After calibration of the displacement sensor, the synchronization accuracy reaches ±1.5mm.

[0066] 2. Tiered unloading (total time 12 hours): Step 1 Unloading (2 hours): Simultaneously lift all jacks at a speed of 5 mm / min, raising the truss by 5 mm. After the wedges loosen, remove the wedges and sliding rails. Check the jack pressure to ensure that the pressure deviation at each point is ≤10%.

[0067] Step 2 Unloading (2.5 hours): Lower the truss by 100mm at a rate of 20mm / cycle. Pause for 5 minutes after every 20mm descent to monitor stress changes. After descent, insert a φ168mm×8mm steel pipe support at the bottom of the support. Remove the jacks and adjust the height of the bottom steel pipe to 277mm (for the next step of support).

[0068] Step 3 Unloading (2.5 hours): Repeat the descent process, lowering it another 100mm. Replace the support steel pipe to a height of 177mm. Monitoring shows that the stress at critical nodes increased from the initial 185MPa to 215MPa, which is below the allowable value of 295MPa.

[0069] Step 4: Unloading (2.5 hours): Continue lowering by 100mm, adjusting the height of the supporting steel pipe to 77mm. Stress monitoring shows a maximum compressive stress of 238MPa, indicating structural stability.

[0070] Step 5: Unloading (2.5 hours): Lower to the design elevation (+22.09m). Install permanent limit devices: Weld a 160mm×120mm×20mm×20mm housing to the bottom of the A-axis support; weld and fix the Q-axis support according to the design drawings. After unloading, stress monitoring showed a maximum stress of 262.5MPa, which meets safety requirements.

[0071] 3. Lateral jacking into place (takes 3 hours): Two 100t hydraulic jacks are arranged along axis A, with a jacking point spacing of 8m. The jacking force is set to 700kN (based on a friction coefficient of 0.15).

[0072] The truss was jacked at a speed of 5 mm / min, with displacement sensors monitoring the process in real time. During the jacking process, the truss moved 35 mm along the span to the design position.

[0073] Weld the support immediately after placement: use E5015 welding rods, preheat temperature 150℃, and control the interpass temperature to no higher than 200℃. Perform 100% ultrasonic testing on the weld.

[0074] 4. Synchronous control and monitoring (entire process): The hydraulic synchronization system collects data every 5 seconds, and the displacement deviation is always controlled within ±2mm.

[0075] Stress monitoring: Data from 20 strain gauges showed that the stress increased steadily during unloading without any abrupt changes. The maximum compressive stress of 262.5 MPa occurred at the Q-axis support, which is lower than the design value of 295 MPa.

[0076] Deformation monitoring: Total station measurements showed that the mid-span deflection of the truss after it was in place was 42mm (design allowable value 60mm), and the verticality deviation was 9mm (allowable value 15mm).

[0077] 5. Quality inspection (takes 2 hours): Weld inspection: All support welds were inspected by ultrasonic testing and no defects were found.

[0078] Position verification: The maximum deviation of the support center is 8mm (the specification requires ≤10mm), and the elevation deviation is ±12mm (±15mm is allowed).

[0079] Documentation: An acceptance report is generated, including stress data, displacement records, and weld inspection certificates.

[0080] Results Verification: The structure passed inspection after construction, and the truss positioning accuracy met design requirements. Compared with traditional methods, the construction period was shortened by 3 days, and no safety incidents occurred. Stress analysis showed that the structure remained in an elastic state throughout the system transformation process, with a safety factor greater than 1.5.

[0081] Example 2: Enhanced control of complex nodes (for ball joint supports) For projects with ball joint supports, the following reinforcement measures should be added: Pre-unloading pretreatment: Weld reinforcing ribs (20mm thick, Q355B) around the ball joint support to improve local stiffness. Install strain gauge monitoring points: Attach triaxial strain gauges to the stress area of ​​the ball joint to monitor multiaxial stress.

[0082] Unloading process adjustments: Reduce unloading speed: Replace 20mm / cycle with 10mm / cycle, and extend the pause time to 10 minutes / cycle. Add temporary support: Install auxiliary support rods (φ120mm×6mm steel pipes) on the side of the ball joint to share the lateral force.

[0083] Welding control: Post-heat welding: Immediately after welding, heat to 250℃, hold for 2 hours, and then cool slowly to reduce residual stress. A segmented welding strategy is adopted: weld the bottom of the support first, then weld the lateral connections to avoid concentrated heat input.

[0084] Results: Stress fluctuation in the ball joint support area was reduced by 15%, and no cracks were generated. The positioning accuracy reached 5mm, which is better than that of conventional joints.

[0085] Key parameter verification: The stress calculation results of key components during the system conversion process are as follows: Lateral continuous beam along axis A (box type 160×160×20×20): maximum normal stress 235.9MPa < 295MPa, safety factor 1.25.

[0086] Q-axis lateral continuous beam (box type 300×160×30×20): maximum normal stress 226.0MPa<295MPa, safety factor 1.30.

[0087] Support bracket (box type 260×160×20×20): maximum shear stress 109.6MPa < 170MPa, safety factor 1.55.

[0088] All calculations met the requirements of the "Standard for Design of Steel Structures" (GB50017-2017), proving the safety of the process.

[0089] Industrial Applicability: This invention has been successfully applied to several large-span projects, such as the 145m span material shed project described in Example 1, as well as a stadium (162m span) and an airport terminal (135m span). Practice has shown that this technology has the following practical advantages: High equipment versatility: Utilizing conventional hydraulic jacks and control systems, the equipment cost is low and it is easy to promote. Safe and reliable construction: No major safety accidents have been recorded, and the structural acceptance rate is 100%. Significant economic benefits: The construction period is shortened by an average of 15-20%, and direct costs are reduced by 10% (due to reduced manpower and machinery idleness). Good environmental adaptability: It can be applied in narrow spaces or spanning construction, such as the complex node treatment in Example 2.

[0090] The overall system conversion process of the spatial truss after cumulative sliding in this invention achieves high-precision synchronous control of the unloading process through a hydraulic synchronous control system. This strictly controls the jack displacement deviation within ±2mm, effectively avoiding stress concentration and structural deformation problems caused by asynchrony in traditional methods. Combined with a staged unloading strategy (five-step descent in 20mm increments) and lateral jacking measures, the truss positioning deviation can be controlled to ≤10mm, far lower than the 20-30mm deviation of traditional processes, significantly improving installation accuracy and safety. Real-time stress monitoring ensures that the maximum compressive stress is always ≤262.5MPa, lower than the allowable stress of 295MPa for Q355 steel, eliminating the risk of structural damage at its source.

[0091] This process, through modular hydraulic equipment and intelligent control algorithms, shortens the system conversion period by approximately 20%, reduces the number of high-altitude operations and temporary support dismantling operations, and lowers labor and machinery costs. Compared to traditional full-span scaffolding or large crane solutions, this method utilizes conventional jacks and track systems, achieving optimized resource allocation and reducing construction costs by more than 10%. Simultaneously, its "curved direct jacking" design simplifies the sliding process, avoids the complex adjustments of step-by-step jacking, and eliminates the need for fall arrest gantry structures in sensitive environments such as those crossing highways, minimizing disruption to existing traffic.

[0092] This technology boasts broad adaptability and can be flexibly applied to complex node scenarios such as spans of 70-162m and ball-joint supports. Through standardized design of supporting brackets and limiting boxes, combined with quality control measures such as post-heat welding and strain monitoring, construction reliability is ensured under varying geological and climatic conditions. Engineering practice has demonstrated that this technology was successfully applied to a 145m span material shed project, achieving a 100% structural acceptance rate with no safety incidents, providing a safe, economical, and replicable solution for large-scale spatial steel structures.

[0093] This invention solves the technical challenge of converting large-span spatial truss systems, provides a complete solution for similar projects, and meets the requirements of industrial applications.

[0094] The implementation principle of this invention is as follows: This invention discloses a process for converting a spatial tubular truss into its overall system after cumulative sliding, relating to the field of steel structure construction technology. This process, through the installation of supporting brackets and a jack system, employs a combination of staged unloading and lateral jacking to achieve precise conversion of the truss from a temporary support state to its designed position. Key steps include step-by-step unloading in 20mm increments, adjustment of the jack bottom support height, hydraulic synchronous control, and lateral limiting measures. This invention solves the problems of poor synchronization and stress concentration in traditional unloading methods, and has advantages such as high positioning accuracy, strong safety, and high construction efficiency, making it suitable for the construction of large-span spatial tubular truss structures.

[0095] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A process for converting a spatial tubular truss system after cumulative sliding, characterized in that, Includes the following steps: Step 1: Install the support brackets and jack system at the truss supports; Step 2: Transfer the truss from its temporary support state to its designed position using a tiered unloading method; Step 3: Adjust the truss into position using lateral jacking measures; Step 4: Synchronously control the displacement and stress during the unloading process.

2. The overall system conversion process after cumulative sliding of a space tubular truss according to claim 1, characterized in that, The supporting bracket is a box-shaped structure with a cross-sectional dimension of 300mm×160mm×30mm×20mm, made of Q355B steel, and welded to the support ball and truss chord.

3. The overall system conversion process after cumulative sliding of a space tubular truss according to claim 1, characterized in that, The jack system includes multiple 100t screw jacks, with two jacks arranged at each support. The bottom of the jacks is supported by a φ168mm×8mm round tube.

4. The overall system conversion process after cumulative sliding of a space truss according to claim 1, characterized in that, The graded unloading involves lowering the truss in five steps, with each step being 20mm in a cycle. After each step of descent, a φ168mm×8mm steel pipe is used as a temporary support, and the bottom support height of the jacks is adjusted.

5. The overall system conversion process after cumulative sliding of a space truss according to claim 4, characterized in that, In the staged unloading process, the bottom support height of the jacks is 277mm, 177mm, and 77mm respectively, and finally descends to the design elevation.

6. The overall system conversion process after cumulative sliding of a space tubular truss according to claim 1, characterized in that, The lateral jacking is achieved using a 100t hydraulic jack, which pushes the truss along its span to the designed position, and then welds a fixed support after the jacking.

7. The overall system conversion process after cumulative sliding of a space tubular truss according to claim 1, characterized in that, The synchronization control is achieved through a hydraulic system, with displacement synchronization deviation controlled within ±2mm, and stress is monitored in real time to ensure it does not exceed the design value.

8. The overall system conversion process after cumulative sliding of a space tubular truss according to claim 1, characterized in that, It also includes lateral limiting measures. The A-axis uses a 160mm×160mm×20mm×20mm housing, and the Q-axis uses a 260mm×160mm×20mm×20mm housing, which is welded to the foundation embedded parts.

9. The overall system conversion process after cumulative sliding of a space truss according to claim 1, characterized in that, Stress monitoring was performed on key nodes during the unloading process, and post-heat welding was used to control the weld quality.

10. The overall system conversion process after cumulative sliding of a space truss according to claim 1, characterized in that, The process is applicable to spatial tubular truss structures installed using the cumulative sliding method. After the truss is in place, the center deviation of the support is no greater than 10mm, and the verticality is no greater than h / 250 and no greater than 15mm.

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