Spoke type cable supported grid roof high-precision construction control method

Abstract

The application discloses a high-precision construction control method for a spoke type cable-supported grid roof, and belongs to the field of large-span space steel structure construction. The method comprises the following steps: two groups of pre-lifted hoisting are in place, step-by-step hinged support is used to realize non-forced installation; the node stiffness is calibrated, the cable clamp elevation is quantitatively adjusted according to the linear relationship between force and displacement, the ring cable and the radial cable are independently controlled and rebound compensation is performed; the support slip and the cable clamp coordinates are monitored in two dimensions, and targeted adjustment is performed to form a closed loop; the deformation amount is determined through whole-process simulation, pre-cambering is implemented, and the closing temperature is controlled. The application realizes millimeter-level control of the cable clamp elevation, non-forced installation of the steel structure, low residual stress, standardization of the process, parameter quantization, and is suitable for large-span spoke type cable-supported grid roof construction.

Description

Technical Field

[0001] This invention relates to the field of construction technology for large-span spatial steel structures and cable-supported grid structures, and more specifically to a high-precision construction control method applicable to spoke-type cable-supported grid roofs, particularly suitable for the "cable-first, steel-later" system construction of large public buildings such as stadiums and convention centers. Background Technology

[0002] Traditional construction of large-span cable-supported grid structures requires the erection of numerous high-altitude support frames, resulting in high costs, long erection periods, large site occupancy, and high risks associated with high-altitude operations. Cable tensioning often employs single-step, integral tensioning, leading to poor synchronization, uneven cable force distribution, and significant structural deviations. Alignment of the roof steel structure during hoisting is difficult, and forced positioning can generate additional internal stress, affecting structural safety and service life. The construction process lacks an integrated closed-loop monitoring and control system encompassing cable force, displacement, and support sliding, making it impossible to coordinate and regulate stress, deformation, and cable force. The hoisting process is simplistic, and the connection of steel structures on the cables can result in forced installation and insufficient lateral stiffness. Cable clamp elevation adjustment is only a qualitative operation, lacking a quantifiable force-displacement relationship, making millimeter-level installation impossible. Monitoring dimensions are limited, lacking a closed-loop control system linking support sliding and cable clamp coordinates. Construction simulation, pre-cambering, and closure temperature monitoring operate independently, failing to form an integrated control system, resulting in high residual stress and low forming accuracy.

[0003] In particular, in traditional "cable-before-steel" construction, those skilled in the art generally believe that a stable load-bearing system is formed after the cable net is tensioned, and the installation accuracy of the subsequent steel structure mainly relies on forced alignment at high altitude and local adjustments, without the need for systematic control of the cable clamp elevation. Therefore, existing construction methods do not consider active adjustment and closed-loop correction of the cable clamps after the steel structure is hoisted, nor do they form an integrated "hoisting-adjustment-monitoring-control" system. These technical biases result in low construction efficiency, poor accuracy, and high safety risks, failing to meet the high standards required for acceptance of large stadiums. Summary of the Invention

[0004] The purpose of this invention is to provide a high-precision, complete, closed-loop, and quantifiable construction control method for spoke-type cable-supported grid roofs, so as to achieve non-forced, highly stable, and precise positioning of the steel structure on the cable, independent millimeter-level adjustment of the cable clamp elevation, dual-dimensional monitoring and closed-loop adjustment throughout the construction process, and integrated control of construction deformation, temperature stress, and residual stress, ultimately improving the structural forming accuracy, construction safety, and work efficiency.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: The method of the present invention includes the following four core steps, and there is a functional synergy between the steps, which together constitute a complete construction control closed loop.

[0006] 1. Method for precise hoisting and positioning of two frames as a group After the cable net is tensioned in place, two adjacent roof trusses are used as a hoisting unit, and a large-tonnage crawler crane is used for symmetrical lifting. Grouping two trusses together significantly improves the in-plane stiffness of the hoisting unit, preventing excessive lateral deflection during single-truss hoisting. The hoisting unit is pre-raised to a certain height above the designed placement position, sufficient to offset the elastic deformation of the lifting equipment, cable sagging, and placement impact. For example, based on simulation calculations of the elastic deformation of the lifting equipment, cable sagging, and placement impact, the pre-raising height can be 0.8m to 1.0m. This pre-raising allows the components to slowly conform to the placement position, eliminating additional stress at the nodes caused by forceful pulling and lifting.

[0007] When the unit is in place, the radial beam is first connected to the pin at point A of the inner chord of the pressure ring truss to form a fixed hinge support. Then, using a 60t hand-operated hoist (or other adjusting device such as a hydraulic jack) and temporary lowering cables for coordinated adjustment, the first row of struts at point B, the second row of struts at point C, and the inner and outer struts of the ring cable at point D are connected in sequence. The entire process is monitored by a total station. The step-by-step hinge support allows the unit to gradually form a stable force system on the flexible cable system. Each connection is completed under low stress, ensuring precise alignment of the pin and the cable clamp hole.

[0008] The hoisting process follows the principles of north-south and east-west symmetry, with installation carried out in groups and cycles, and finally closure at the four corners. Symmetrical construction ensures even distribution of cable forces and support reactions, avoiding unilateral concentrated loading that could lead to cable imbalance and excessive support displacement.

[0009] 2. Method for dynamic adjustment of cable clamp elevation down to the millimeter level Ring cable clamps are installed on the circumferential cables, and radial cable clamps are installed on the radial cables. The vertical stiffness of the nodes is determined through finite element simulation, and pull-out tests are conducted on selected typical cable clamps in the field for verification. Specific values ​​can be determined through calibration based on the cable clamp construction, cable diameter, and cable force level of different projects. The adjustment amount is calculated based on the linear relationship between force and displacement, using the formula ΔZ=F / k, where ΔZ is the elevation adjustment amount, F is the applied vertical force, and k is the vertical stiffness of the node. This formula transforms traditional empirical adjustment into quantitative and controllable adjustment.

[0010] A ring cable clamp is equipped with a downward pull cable, and a radial cable clamp is equipped with a radial pull cable, forming an independent control unit. Single-point adjustment within ±10mm does not interfere with adjacent nodes, avoiding mutual coupling between the ring and radial cable adjustments. After the roof unit is hoisted, the cable clamps sink 10mm to 27mm due to their own weight. The pull cables are unloaded in stages according to the corresponding stiffness values, allowing the cable clamps to spring back to the design elevation. The final adjustment accuracy is ±1mm, the cable clamp elevation deviation is ≤±2mm, and the cable force deviation is ≤±10%.

[0011] 3. Two-dimensional monitoring and closed-loop adjustment method Supports were installed below the pressure ring truss, and X / Y slippage of the supports was monitored. Three-dimensional coordinate monitoring was performed on key cable clamps such as the ring cable clamps and radial cable clamps. A total station with reflectors was used to monitor the coordinates, and a calibrated oil pump pressure gauge was used to monitor the cable force. Data was collected immediately after each key working condition was completed.

[0012] After data collection, it is compared with theoretical values. The deviation judgment threshold is determined comprehensively based on the structural stress characteristics, specification limits, and construction operability. If the deviation exceeds the tolerance, targeted adjustments are made, and the process proceeds to the next step only after passing a retest. This forms a closed-loop control process of "data collection → comparison → judgment → adjustment → retest → next step". Closed-loop control can correct the effects of construction errors, temperature deformation, hoisting deviations, etc. in real time, avoiding the accumulation of errors.

[0013] It is worth noting that the closed-loop control of the present invention is not limited to step three, but uses the monitoring data synchronously for the dynamic updating of the cable clamp adjustment parameters in step two and the adjustment of the closing timing in step four, thereby realizing cross-step coupling correction throughout the entire process.

[0014] 4. Integrated control method for simulation, pre-arching and closure temperature A multi-condition construction simulation model was established using finite element software. The entire process, from the installation of the substructure to the unloading of the supports, was modeled segment by segment according to the actual construction steps, and the deformation, stress and support displacement at each stage were accurately predicted.

[0015] Pre-cambering is implemented at the mid-span and support nodes of the ring beam based on the maximum downward deflection predicted by simulation, and configuration compensation is performed on the compression ring truss based on the planar displacement predicted by simulation. Curtain wall node deformation is small, so no pre-deformation is required. Pre-cambering can offset the downward deflection caused by the structure's self-weight and construction loads in advance.

[0016] The closure temperature should be controlled within a preset temperature range, which should be determined based on local climate statistics and finite element analysis of temperature effects. Construction should be carried out during periods of stable temperature to reduce additional temperature stress on the structure after closure.

[0017] As is well known to those skilled in the art, in the construction of large-span cable-supported grid structures, hoisting accuracy, cable clamp elevation, cable force distribution, and temperature stress are four major challenges that are mutually coupled and influence each other. Traditional methods address these challenges separately, resulting in neglecting some aspects. This invention proposes for the first time to integrate hoisting attitude pre-control, stiffness quantitative adjustment, dual-dimensional closed-loop monitoring, simulation pre-deformation, and temperature control into a unified collaborative system. By utilizing monitoring data throughout each step to achieve dynamic correction, it solves the fundamental problem of high-precision forming at the system level.

[0018] The above four steps are executed in sequence, and the monitoring data of step three can be fed back to steps two and four for dynamic correction, forming a complete construction control closed loop. Its overall technical effect exceeds the sum of the individual effects of each step.

[0019] Compared with existing technologies, this invention integrates hoisting, adjustment, monitoring, and control into a complete set of methods, overcoming the limitations of single technical means and aligning with the priority review strategic areas of green building and high-end construction equipment. Using this invention significantly improves construction accuracy, achieving millimeter-level control of cable clamp elevation, non-forced installation of steel structures, and high-precision control of cable force and support displacement. Through dual-dimensional closed-loop monitoring, construction risks can be warned in advance, effectively avoiding error accumulation and significantly improving construction safety. Simultaneously, integrated control helps reduce residual stress and temperature stress in the structure, enhancing structural durability. This invention features standardized processes, quantified parameters, and a universal stiffness calibration method that can be easily replicated and promoted to similar large-span cable-supported grid projects. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the hoisting operation layout according to an embodiment of the present invention; Figure 2 , Figure 3 This is a schematic diagram of a pre-lifting hoisting of two frames as a set according to an embodiment of the present invention; Figures 4-8 This is a diagram showing the connection sequence of the step-by-step hinged support placement nodes according to an embodiment of the present invention; Figure 9 , Figure 10 This is a schematic diagram of the temporary pull-down cable and cable clamp arrangement according to an embodiment of the present invention; Figure 11 This is a schematic diagram of the millimeter-level adjustment tooling composition according to an embodiment of the present invention; Figure 12 , Figure 13 This is a plan view of the support monitoring points according to an embodiment of the present invention; Figure 14 This is a flowchart of the dual-dimensional monitoring closed-loop control process according to an embodiment of the present invention; Figures 15-22 This is a simulation deformation cloud map of the construction stage in an embodiment of the present invention; Figure 23 This is a diagram showing the closed state of the ring truss according to an embodiment of the present invention; Figure 24 This is a diagram showing the steel roof in its closed state according to an embodiment of the present invention. Detailed Implementation

[0021] The following is in conjunction with the appendix Figures 1 to 24 The specific implementation method of the high-precision construction control method for a spoke-type cable-supported grid roof of the present invention will be further described in detail.

[0022] This invention was implemented in the roofing project of the 60,000-seat football stadium at the Taranta Sports City in Kenya, a representative example of a "cable-before-steel" system stadium. Those skilled in the art will understand that the following values ​​are examples specific to this project and do not constitute a limitation on the scope of protection of this invention. In practical applications, the corresponding parameters can be determined based on simulation and on-site calibration.

[0023] I. Project Overview and Overall Deployment The stadium roof employs a spoke-type cable-supported grid structure with an elliptical plan, approximately 280m along its major axis and 230m along its minor axis. The roof consists of pressure ring trusses, radial beams, circumferential cables, radial cables, and struts. After the cable system is tensioned, the steel roof structure units are installed on top. To achieve scaffold-free construction and ensure millimeter-level precision, the four-step construction control system described in this invention is employed.

[0024] 2. Two frames are pre-lifted and hoisted into place as a set. like Figure 1 As shown, two 650t crawler cranes were used, positioned symmetrically on the north and south sides of the stadium. Two adjacent roof trusses were considered as a single lifting unit, with a total unit weight of approximately 85t. The two trusses were connected by temporary cross bracing to improve in-plane stiffness. Lifting points were located at the upper chord nodes of the trusses, and each lifting point was equipped with 200t-class slings and shackles.

[0025] During hoisting, a dual-crane lifting system raises the entire unit to 0.9m above its designed placement position. This pre-lifting height was determined through finite element simulation: considering the elastic elongation of the lifting equipment (approximately 15mm), the sag of the cables under the hoisting load (approximately 8mm), the impact deformation during placement (approximately 5mm), and a safety margin, a total height of 0.9m was determined. After pre-lifting, the unit is slowly lowered to bring it into place at near-zero speed, avoiding any forced pulling or lifting. Figure 2 The hoisting unit was shown in its pre-raised position. Figure 3 This further illustrates the arrangement of the two trusses connected by cross braces to form a rigid unit and the arrangement of the suspenders.

[0026] The sequence of step-by-step hinge placement is as follows: Figures 4 to 8 The diagram uses the letters A, B, C, and D to mark four key connection nodes, whose meanings are as follows: Point A: The pin connection node between the end of the radial beam and the inner chord of the pressure ring truss. This node is the first fixed hinge support point. Point B: The pin connection node between the lower end of the first column of struts and the corresponding radial cable clamp; Point C: The pin connection node between the lower end of the second column strut and the corresponding radial cable clamp; Point D: The pin connection node between the inner and outer struts of the circumferential cable and the cable clamp of the circumferential cable.

[0027] The connection order is A→B→C→D in sequence: Step 1 (e.g.) Figure 4 (As shown): With the crane in the lifting state, first connect the end of the radial beam to the inner chord of the pressure ring truss and insert the pin at point A to form a fixed hinge support point. At this time, the crane bears most of the unit weight. Step 2 (as shown) Figure 5 As shown): By adjusting the unit posture with the adjustment device (60t hand chain hoist), the lower end of the first row of support rods is naturally aligned with the radial cable at point B and inserted into the pin shaft; Step 3 (as shown) Figure 6 (As shown): Continue to slowly release the hook and adjust the hand chain hoist so that the lower end of the second column of support rods is aligned with the radial cable at point C, and then insert the pin. Step 4 (as shown) Figure 7 (As shown): Then connect the inner and outer struts of the circumferential cable to the pin clamped at point D of the circumferential cable; Step 5 (as shown) Figure 8 (As shown): After verifying the coordinates of each control point in the unit with the total station, the stabilizing cable is tightened and the crane slowly releases the hook to unload the load.

[0028] The entire step-by-step connection process was carried out under real-time monitoring by a total station. Before each step of the connection, it was ensured that the height difference between adjacent components was ≤3mm and the alignment deviation of the pin holes was ≤1mm, which ensured the natural alignment of the pin holes at each step and eliminated the additional stress caused by forced pin insertion.

[0029] III. Composition of Millimeter-Level Adjustment Fixtures and Elevation Adjustment Methods A circumferential cable clamp is provided on the circumferential cable, and a radial cable clamp is provided on the radial cable. The radial cable clamp includes a first radial cable clamp near the side of the circumferential cable clamp and a second radial cable clamp away from the side of the circumferential cable clamp. Figure 9 , Figure 10 The arrangement of the temporary lower cables and cable clamps is further illustrated, in which... Figure 9 This is a temporary overall layout diagram of the lower cable. Figure 10 This diagram shows the positional relationship between the cable, the cable clamps, and the cable tensioning system. Each cable clamp node is equipped with a tensioning adjustment system, mainly consisting of cable clamp 1, precision-rolled threaded steel bar assembly 5, tensioning jack 3, thrust box 4, transfer box 2, transfer beam 6, and grandstand beam 7 (see attached diagram). Figure 11 The adjustment method is as follows: First, the vertical stiffness k of each cable clamp node was calibrated through finite element simulation and field pull-out tests. The calibration results for this project are as follows: the stiffness of the first radial cable clamp is 5.9 kN / mm, the stiffness of the second radial cable clamp is 6.8 kN / mm, and the stiffness of the circumferential cable clamp is 10.0 kN / mm.

[0030] Before the roof is hoisted, a rough adjustment is carried out: based on the initial elevation deviation predicted by the construction simulation, the required initial tension force is calculated according to the formula ΔZ=F / k, and applied in stages to make the cable clamp elevation close to the design value within ±5mm.

[0031] After the roof unit is hoisted into place, fine-tuning is performed: the elevation of each cable clamp is measured using a total station, the difference ΔZ between the actual elevation and the design elevation is calculated, and the required tension or relaxation force is calculated using the same formula. Minor adjustments are made using jacks, and repeated measurements are taken with the total station until the elevation deviation is ≤ ±1mm. Each cable clamp is adjusted independently, and during single-point adjustment, the elevation change between adjacent cable clamps is ≤1mm, ensuring no interference.

[0032] After the roof is fully hoisted, the cable clamps will sink by 10mm to 27mm due to the weight of the steel structure. At this point, the locking device of the jacks is loosened in stages, and the elastic recoil of the precision-rolled threaded steel bar is used to make the cable clamps spring back to the design elevation.

[0033] Each cable clamp corresponds to a set of precision-rolled threaded steel bars and a jack that can be operated independently. During single-point adjustment, the elevation change between adjacent cable clamps is ≤1mm, achieving independent control of the circumferential and radial cable adjustments without interference. This avoids the problem of positional loss of control in traditional pull cables where "changing one part affects the whole".

[0034] IV. Dual-dimensional monitoring and closed-loop adjustment (a) Layout of monitoring points (e.g.) Figure 12 and Figure 13 (As shown) like Figure 12 , Figure 13 As shown, this project sets up two types of support monitoring points below the pressure ring truss: ZZ1 supports are the main load-bearing supports (48 in this embodiment), arranged at the connection between the pressure ring truss and the substructure; ZZ2 supports are secondary load-bearing supports, arranged at other locations. A reflector is attached to each support for X / Y direction horizontal slip monitoring using a total station. ZZ1 supports are the key control point, as their slip directly determines the structural configuration.

[0035] Meanwhile, three-dimensional coordinate monitoring is performed on each cable clamp (144 cable clamps, including 48 ring cable clamps, 48 ​​first radial cable clamps, and 48 second radial cable clamps), and a special reflective sheet is attached to the top of each cable clamp.

[0036] (II) Monitoring Equipment and Frequency Coordinate measurement: Leica TS60 total station, angle measurement accuracy 0.5″, distance measurement accuracy ±1mm+1.5ppm, one measurement per working condition (approximately every 2 hours).

[0037] Cable tension measurement: Calibrate the oil pump pressure gauge (accuracy class 1.5), and take the reading with the jack. Record the reading after each adjustment.

[0038] Temperature measurement: Electronic thermometer (accuracy ±0.5℃) monitors ambient temperature and component temperature, and records the temperature every hour.

[0039] (III) Closed-loop control process After each critical work phase (lifting, assembly, unloading) is completed, immediately execute the following closed-loop process, such as... Figure 14 As shown: Data acquisition: The coordinates of each cable clamp and support were measured using a total station, the hydraulic pressure gauge was used to read the cable force of each pull cable, and the ambient temperature was recorded simultaneously.

[0040] Comparison with theoretical values: Input the measured data into a pre-set comparison table and calculate the deviation value. The theoretical values ​​are derived from Midas construction phase simulation.

[0041] Deviation judgment: Determine whether the deviation exceeds the threshold (Z-direction deviation of cable clamp ≤ ±120mm, support slippage ≤ 5mm, cable force deviation ≤ ±10%).

[0042] Targeted adjustment: If the elevation of a cable clamp exceeds the tolerance, calculate the adjustment amount according to ΔZ=F / k and adjust the cable clamp independently. If the support slippage exceeds the limit, suspend subsequent hoisting in that area, adjust the hoisting sequence, or temporarily reinforce it.

[0043] Retest passed: Retest immediately after adjustment to confirm that the deviation is within the allowable range.

[0044] Proceed to the next step: After all deviations are within acceptable limits, issue a process handover form and proceed to the next construction step.

[0045] V. Integrated control of simulation, pre-arching and closing temperatures (I) Simulation of the entire construction process A global finite element model was built using Midas Gen, comprising approximately 150,000 elements. The following eight working conditions were simulated, and the deformation contour plots for each condition are shown below. Figures 15 to 22 : Operating Condition 1 ( Figure 15 ): The initial state after the ring beam and pressure ring truss are installed, with the structure's self-weight causing initial deformation.

[0046] Operating Condition 2 ( Figure 16 ): 48 radial cables were simultaneously lifted into place, cable force began to build up, and the roof as a whole showed an upward arching trend.

[0047] Operating Condition 3 ( Figure 17 ): 48 ring-shaped downward tensioning cables are tensioned symmetrically in batches and grades, and the ring cable system is gradually stressed.

[0048] Operating Condition 4 ( Figure 18 ): 96 radial down cables were tensioned symmetrically in batches and grades, and the radial cable system was further adjusted.

[0049] Operating Condition 5 ( Figure 19 The roof steel structure was hoisted into place symmetrically in groups of two, and the structural deformation gradually increased.

[0050] Operating Condition 6 ( Figure 20 ): The roof structure is joined at the four corners, and the overall structure is basically formed.

[0051] Operating Condition 7 ( Figure 21 ): The radial pull cables are unloaded in batches and stages, the internal forces of the structure are redistributed, and the cable clamps rebound.

[0052] Operating Condition 8 ( Figure 22 ): The ring is unloaded in batches and stages, pulling the cable downwards until the final state is stable and the deformation converges.

[0053] For each working condition, structural deformation, cable force changes, support reaction force, and slippage are calculated to provide a basis for pre-arching and closure temperature control.

[0054] (II) Pre-arching and Positional Compensation Based on the simulation results: The maximum deflection at mid-span of the ring beam after all loads are applied is 48mm. Therefore, the ring beam is pre-arched at mid-span with an arch of 48mm and at both ends of the support with an arch of 24mm (parabolic variation) during fabrication.

[0055] The maximum horizontal displacement of the pressure ring truss in the plane is about 20mm (outward). During installation, pre-offset compensation is performed based on an inward offset of 20mm.

[0056] The deformation of the curtain wall X-truss node is ≤5mm, and no pre-deformation is required.

[0057] (III) Closure Temperature Control Based on local climate statistics (annual average temperature 19.8℃, maximum daily temperature difference 12℃), the closure temperature range was determined to be 20±5℃. During construction, temperature monitoring points were set at the closure joint of the ring truss and steel roof. Closure welding could only be carried out when the component temperature stabilized between 18 and 22℃ and the change was ≤1℃ for 2 consecutive hours. The closure gap was reserved according to the design value of 20℃, and the gap was adjusted by 0.5mm for every 1℃ deviation of the actual temperature.

[0058] Figure 23 , Figure 24 The structural states of the ring truss closure and the steel roof closure are shown respectively. Figure 23 The diagram shows the closed state of the ring truss, illustrating the docking configuration and temporary locking device at the four corners of the truss. Figure 24 This diagram shows the closure status of the steel roof, illustrating the arrangement of closure nodes at the four corners of the entire steel roof structure. Closure construction should be carried out during periods of stable temperature to minimize the impact of temperature stress on the structure. Implementation effect

[0059] After the project was completed, a test report issued by a third-party testing agency indicated that: Final deviation of cable clamp elevation: maximum value +1.8mm, minimum value -1.5mm, pass rate 100%; Cable tension deviation: maximum deviation 7.2%, average deviation 4.5%; Support displacement deviation: maximum 3.1 mm, average 1.8 mm; The structural lines are smooth, with no forced installation, and all pin connection holes are naturally aligned. It meets the requirements of FIFA standards and China's "Standard for Acceptance of Construction Quality of Steel Structures" GB 50205.

[0060] This method has been successfully verified in this project and can be directly extended to the construction of similar large-span cable-supported grid roofs.

[0061] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A high-precision construction control method for spoke-type cable-supported grid roofs, Its features are, Includes the following steps: Step 1: Pre-lift and precisely hoist two hulls into place as a set. After the cable net is tensioned in place, two adjacent roof trusses are used as a hoisting unit. The hoisting equipment is used to lift the unit symmetrically to raise it to a certain height above the designed position. This height is sufficient to offset the elastic deformation of the hoisting equipment, the sagging of the cable system, and the impact of the placement. Then, the unit is placed in stages with hinged supports: first, the radial beam is connected to the first pin node of the inner chord of the pressure ring truss to form a fixed hinge support point. Then, the unit posture is adjusted in coordination with the adjustment device, and the remaining pin nodes are connected in sequence. The entire process is monitored by measuring equipment. Step 2: Dynamic adjustment of cable clamp elevation down to the millimeter level Ring cable clamps are installed on the circumferential cables, and radial cable clamps are installed on the radial cables. The vertical stiffness of each cable clamp node is determined through construction simulation or field tests, and the adjustment amount is calculated according to the linear relationship between force and displacement. Ring-down pull cables are installed on the ring cable clamps, and radial pull cables are installed on the radial cable clamps, and the elevation of each cable clamp is independently adjusted. After the roof unit is hoisted, the pull cables are unloaded in stages according to the corresponding stiffness values, so that the cable clamps spring back to the design elevation. Step 3: Dual-dimensional monitoring and closed-loop adjustment Supports are installed below the pressure ring truss, and horizontal slippage of the supports is monitored; three-dimensional coordinate monitoring is performed on the ring cable clamps and radial cable clamps; coordinates are monitored using measuring equipment, and cable force is monitored using a calibrated force measuring device; data are collected after each key working condition is completed and compared with theoretical values. If the deviation exceeds the preset threshold, targeted adjustment is performed until the retest is qualified before proceeding to the next process. Step 4: Integrated control of simulation, pre-arching and closing temperatures A multi-condition construction simulation model was established using finite element software to simulate the entire process from substructure installation to support unloading. Based on the simulation results, pre-arching was implemented on the ring beam and support nodes according to the simulated maximum deflection, and the pressure ring truss was compensated for its displacement according to the simulated planar displacement. The closing temperature of the ring beam and pressure ring truss was controlled within the preset temperature range, and construction was carried out during periods of stable temperature difference.

2. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, The pre-lifting height in step one is 0.8m to 1.0m; the adjusting device is a hand-operated hoist or a hydraulic jack; the measuring equipment is a total station.

3. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, The radial cable clamp includes a first radial cable clamp near the circumferential cable clamp side and a second radial cable clamp away from the circumferential cable clamp side; the adjustment amount is calculated by the formula ΔZ=F / k, where ΔZ is the elevation adjustment amount, F is the applied vertical force, and k is the node vertical stiffness.

4. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, In step two, the single-point adjustment range is ±10mm, the adjustment accuracy is ±1mm, the final elevation deviation of the cable clamp is ≤±2mm, and the cable force deviation is ≤±10%.

5. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, In step three, the control thresholds are set as follows: vertical deviation of cable clamp ≤ ±120mm, sliding deviation of support ≤ 5mm, and cable force deviation ≤ ±10% of the design value.

6. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, In step four, the pre-camber at the mid-span and support nodes of the ring beam is 48mm, and the planar configuration compensation of the pressure ring truss is 20mm; the closing temperature is controlled within the range of 20±5℃.

7. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, The closed-loop control process in step three is as follows: data acquisition → comparison with theoretical value → deviation judgment → targeted adjustment → retesting and passing → proceeding to the next process.

8. The high-precision construction control method for spoke-type cable-supported grid roof according to claim 1, characterized in that, The step-by-step hinged support placement sequence in step one is as follows: first connect the radial beam to the pin joint of the inner chord of the pressure ring truss, and then connect the first row of struts, the second row of struts, and the inner and outer struts of the ring cable in sequence.

9. The high-precision construction control method for spoke-type cable-supported grid roof according to any one of claims 1 to 8, characterized in that, The method described above is used for the "cable-first, steel-later" system construction of large-span spoke-type cable-supported grid roofs for stadiums and convention centers.

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