Anti-slip X-shaped non-orthogonal tensile roof construction method

Abstract

This invention provides a construction method for an X-shaped non-orthogonal tensioned cable structure roof with anti-slip properties. The X-shaped non-orthogonal tensioned cable structure roof includes an upper tensioned beam, a middle strut, and lower cables. The upper and lower ends of the strut are hinged to the tensioned beam and cables respectively through pin holes. Ten cables are arranged in groups of two intersecting cables, named cable group 1, cable group 2, cable group 3, cable group 4, and cable group 5 according to their position on the roof from highest to lowest. The roof construction method includes hoisting the upper tensioned beam; hoisting and extending the cables, and installing cable clamps at the marked positions on the cables; simultaneously installing anti-slip devices at the connection points between the cable clamps and the struts; using Midas Gen to establish a finite element model of the X-shaped non-orthogonal tensioned cable roof structure to determine the step-by-step tensioning scheme; and employing dual monitoring of the strut and cable clamp during tensioning. This invention proposes an anti-slip construction method for the cable clamp nodes of a tensioned cable structure roof, solving the problems of strut tilting and cable clamp deflection that easily occur during tensioning.

Description

Technical Field

[0001] This invention relates to the field of building structure construction technology, and in particular to a method for constructing an anti-slip X-shaped non-orthogonal tensioned roof. Background Technology

[0002] Large-span tensioned beam roof structures are increasingly used in various public buildings. Compared with conventional flat space frames and space trusses, tensioned structures have significant advantages such as smaller structural deformation, less steel consumption, higher force transmission efficiency, and a lighter, more aesthetically pleasing appearance. However, as a hybrid structural system, tensioned beam construction still faces challenges in many aspects, including tension control, stability during structural forming, joint construction accuracy, and simulation analysis. For irregularly shaped tensioned beams, the increased spatial geometric complexity makes the control requirements for these aspects even more stringent. Therefore, strict tension control, precise morphological monitoring, and detailed joint design during construction are crucial to the construction quality of such complex tensioned structures. Summary of the Invention

[0003] To address the issue of strut tilting and cable clamp deflection during tensioning in pin-hinged cable clamp nodes of X-shaped non-orthogonal tensioned structures, this invention proposes an anti-slip construction method for cable clamp nodes in roof tensioned structures. The method includes anti-deflection reinforcement treatments for single and double cable clamp nodes, as well as synchronous tensioning and strut / cable clamp position monitoring methods. It also proposes a method for correcting cable clamp node deviation during trial tensioning.

[0004] A construction method for an anti-slip X-shaped non-orthogonal tensioned cable structure roof, wherein the X-shaped non-orthogonal tensioned cable structure roof includes an upper tensioned beam, a middle strut, and lower cables. The upper and lower ends of the strut are hinged to the tensioned beam and the cables respectively through pins passing through pin holes. Each pair of cables in the 10-cable structure forms a group, named cable group 1, cable group 2, cable group 3, cable group 4, and cable group 5 according to their position on the roof from high to low. The roof construction method includes the following steps:

[0005] Step 1: Upper tensioned beam hoisting: Assemble the struts and cable clamp cover plates on the ground, and then install them under the tensioned beam. Divide the roof into sections and install the upper tensioned beams with the struts and cable clamp cover plates installed according to the sections.

[0006] Step 2, Cable Installation: Hoist and extend the cables, and install the cable clamps at the marked positions on the cable body. At the same time, install anti-slip devices at the connection between the cable clamps and the struts.

[0007] Step 3, Cable Tensioning: A finite element model of the X-shaped non-orthogonal tensioned cable roof structure is established using Midas Gen to determine the step-by-step tensioning. Each level of tensioning should be carried out sequentially from cable group 5 to cable group 1. The fixed end cable head and the tensioning end cable head of each cable group are set on the same side. Single-sided synchronous tensioning is used to tension the cable groups. Two sets of tensioning equipment are used to apply prestress to the tensioning ends of the two cables in the same X-shaped non-orthogonal cable group on the same side. The tensioning is monitored by both struts and cable clamps.

[0008] Furthermore, the anti-slip device mentioned in step 2 is a pad plate installed between the two sides of the cable clamp ear plate and the two sides of the outer ear plate of the support rod.

[0009] Furthermore, in step 3, the pre-tensioning target force is determined by the structural deformation control method. The two cables in each cable group are not arranged symmetrically. Finally, the pre-tensioning values ​​of the X-shaped cables are determined to be 400kN and 530kN, respectively. The step-by-step tensioning is a three-stage tensioning. Before formal tensioning, it is necessary to pre-tighten with 5% of the pre-tensioning value. The tensioning forces of the three stages are 30%, 70%, and 100% of the design value, respectively.

[0010] Furthermore, in step 3, the monitoring points in the strut-clip dual monitoring are arranged on the upper S2 strut and lower S3 strut on the side of cable group 1, and on the middle S1 strut in the middle span of cable group 1, on the upper T2 strut and lower T3 strut on the side of cable group 5 symmetrical to cable group 1, on the middle T1 strut in the middle span of cable group 5, and on the middle Z1 strut in the middle span of cable group 3. Strain gauges are symmetrically arranged in the middle position of each monitoring point strut, and strain gauges are symmetrically arranged on the outer ear plates on both sides of each monitoring point strut. All strain gauges are electrically connected to the data acquisition box, and the acquisition box is electrically connected to the controller.

[0011] Furthermore, in step 3, if cable clamp deflection occurs due to unbalanced force during tensioning, a cable clamp node correction scheme is selected to correct the cable clamp deflection.

[0012] Furthermore, the cable clamp node correction scheme is as follows: By verifying the anti-slip bearing capacity of the cable clamp, the anti-slip bearing capacity of the cable clamp is compared with the design value of the cable force difference on both sides of the cable clamp to verify whether the anti-slip force of the cable clamp meets the specification requirements. Using the cable clamp specifications and bolt tightening force as test variables, multiple verifications are performed. Finally, cable clamps whose anti-slip force meets the specification requirements are obtained. Then, the original X-shaped non-orthogonal cables are unloaded in stages, and the cable clamps in the original X-shaped non-orthogonal cables are replaced with cable clamps whose anti-slip force meets the specification requirements. Based on the verification results, step-by-step and graded trial tensioning is carried out again.

[0013] Furthermore, the verification process for replacing the cable clamp in step 3 is as follows: Based on the analysis results of the structure using the MidasGen finite element method, cable group 1 is identified as the cable group bearing the maximum cable force. The cable clamp with the largest difference in cable force between its two sides in cable group 1 is the clamp at the 1 / 2 span. The verification is performed using the clamp at the 1 / 2 span of cable group 1. This clamp is made of Q355C steel, with chamfered edges at the cable holes. The cable discs are connected by four M20-10.9S grade bolts. The design preload of the M20-10.9S grade bolts is 155kN, and the design value for the difference in cable force between the two sides of the clamp is 326.5kN.

[0014] Based on relevant standards such as the "Design Standard for Cable-stayed Structure Joints" (T / CECS1010-2022) and the "Design Standard for Steel Structures" (GB50017-2017), the anti-slip force is verified as follows:

[0015] The sum of the effective tightening forces of all high-strength bolts on the cable clamp for:

[0016]

[0017] in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts.

[0018] The anti-slip design load-bearing capacity of the cable clamp for:

[0019]

[0020] in, The coefficient of friction between the cable body and the cable clamp is 0.2 for a sealed cable with exposed steel wire. The safety factor for the anti-slip design bearing capacity of the cable clamp is taken as 1.65.

[0021] Comparison of the anti-slip bearing capacity of the cable clamp and the design value of the cable force difference on both sides of the cable clamp have to:

[0022]

[0023] Therefore, the slip resistance of the cable clamp at the 1 / 2 span of cable group 1 does not meet the code requirements, and the cable clamp needs to be redesigned. Using larger cable clamps and higher bolt tightening forces as variables, multiple calculations were performed, resulting in a cable clamp secured by eight M24-10.9S bolts. The design value of the M24-10.9S bolt preload is 225kN. Based on relevant codes such as the "Standard for Design of Cable Structure Joints" (T / CECS1010-2022) and the "Standard for Design of Steel Structures" (GB50017-2017), the slip resistance of the cable clamp secured by eight M24-10.9S bolts was calculated as follows: The sum of the effective tightening forces of all high-strength bolts on the cable clamp secured by eight M24-10.9S bolts is:

[0024]

[0025] in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts.

[0026] The anti-slip design load-bearing capacity of the cable clamp for:

[0027] Comparison of the anti-slip bearing capacity of the cable clamp and the difference in cable tension on both sides of the cable clamp The design is worthwhile:

[0028]

[0029] After detailed design, the anti-slip force of the cable clamp secured by eight M24-10.9S bolts meets the specification requirements.

[0030] Furthermore, in step 3, the cable clamps at the 1 / 2 span of cable groups 1, 2, 3, 4 and 5 are replaced with cable clamps secured by eight M24-10.9S bolts.

[0031] The beneficial effects of this invention are as follows: This invention proposes a set of synchronous tensioning construction control schemes for cross-tensioned beams. Simultaneously, combining the structural characteristics of the hinged connection between the strut and cable clamp, it establishes an integrated strut and cable clamp position monitoring method. It also includes a method for correcting cable clamp node deviation during trial tensioning. This invention saves construction costs, significantly reducing material and labor expenses; it reduces construction delays, as local testing and adjustments can shorten the overall processing time and reduce losses due to project stagnation caused by full rework; and it offers controllable risks, as the effectiveness of the scheme is verified on a small scale, avoiding the economic risk of blindly investing and failing to achieve the expected results. Attached Figure Description

[0032] Figure 1 This is a distribution diagram of an anti-slip X-shaped non-orthogonal tensioned cable group for a roof according to the present invention;

[0033] Figure 2 This is a distribution diagram of monitoring points for a dual monitoring system of an X-shaped non-orthogonal tensioned roof strut and cable clamp for anti-slip design, as described in this invention.

[0034] Figure 3 This is a schematic diagram of the strut layout of an anti-slip X-shaped non-orthogonal tensioned roof strut-clip dual monitoring strain gauge according to the present invention.

[0035] Explanation of symbols in the attached diagram:

[0036] 1. Strain gauge, 2. Support rod. Detailed Implementation

[0037] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual images. They should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0039] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention 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. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0040] In the description of this patent, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; 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 refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] A construction method for an anti-slip X-shaped non-orthogonal tensioned cable structure roof, such as... Figures 1 to 3As shown, the X-shaped non-orthogonal tensioned cable structure roof includes an upper tensioned beam, a middle strut, and lower cables. The upper and lower ends of the strut are hinged to the tensioned beam and cables respectively via pins passing through pin holes. Each pair of cables in the 10-cable structure forms a group, named cable group 1, cable group 2, cable group 3, cable group 4, and cable group 5 according to their position on the roof from highest to lowest. The roof construction method includes the following steps:

[0042] Step 1: Upper tensioned beam hoisting: Assemble the struts and cable clamp cover plates on the ground, and then install them under the tensioned beam. Divide the roof into sections and install the upper tensioned beams with the struts and cable clamp cover plates installed according to the sections.

[0043] Step 2, Cable Installation: Hoist and extend the cables, and install the cable clamps at the marked positions on the cable body. At the same time, install anti-slip devices at the connection between the cable clamps and the struts.

[0044] Step 3, Cable Tensioning: A finite element model of the X-shaped non-orthogonal tensioned cable roof structure is established using Midas Gen to determine the step-by-step tensioning. Each level of tensioning should be carried out sequentially from cable group 5 to cable group 1. The fixed end cable head and the tensioning end cable head of each cable group are set on the same side. Single-sided synchronous tensioning is used to tension the cable groups. Two sets of tensioning equipment are used to apply prestress to the tensioning ends of the two cables in the same X-shaped non-orthogonal cable group on the same side. The tensioning is monitored by both struts and cable clamps.

[0045] In the X-shaped non-orthogonal tensioned cable structure of this invention, the struts, their upper beams, and lower cable clamps are all connected by radial spherical bearings. These bearings have a relatively flexible out-of-plane deflection capability, making the structure prone to strut tilting, cable clamp deflection, and substandard camber during tensioning. Furthermore, the unique shape of the X-shaped oblique intersection of the steel cables creates numerous unbalanced forces at the cable intersections, further exacerbating out-of-plane instability. To address the core construction challenges of precision and stability control during the single-sided synchronous tensioning of the X-shaped non-orthogonal tensioned cable structure, this invention discloses a construction control scheme for the synchronous tensioning of cross-tensioned beams. Simultaneously, considering the hinged connection between the struts and cable clamps, an integrated strut-clip dual monitoring system is established. Additionally, anti-eccentric reinforcement treatment is applied to single-clip and double-clip nodes during cable installation.

[0046] Furthermore, the anti-slip device mentioned in step 2 is a pad installed between the two sides of the cable clamp ear plate and the two sides of the outer ear plate of the strut. There are two types of cable clamp nodes in the X-shaped cross-tensioned structure: a single cable node at 1 / 4 span and a double cable node at 1 / 2 span. To limit the out-of-plane deflection of the radial joint bearing at this location, a circular pad is added between the locking middle ear plate and the two outer ear plates below the strut during construction. For the 1 / 4 span cable clamp, the anti-displacement target is mainly achieved by adding a permanent circular pad. For the double cable node at 1 / 2 span, in addition to the anti-displacement treatment using the aforementioned 1mm gap control pad, an anti-slip reinforcement design is also required based on the cable clamp under the most unfavorable working conditions.

[0047] Furthermore, in step 3, the pre-tensioning target force is determined using a structural deformation control method. The two cables in each cable group are not perfectly symmetrically arranged. The final pre-tension values ​​for the X-shaped cables are determined to be 400kN and 530kN, respectively. The tensioning is performed in three stages: 5% of the pre-tension value is required before the formal tensioning. The tension forces for the three stages are 30%, 70%, and 100% of the design value, respectively. Based on the original three-stage tensioning process, the tensioning control flow is further refined, broken down into multiple tensioning steps. The requirement to pre-tighten by 5% of the pre-tension value before the formal tensioning is added, thereby achieving more precise control over the synchronous tensioning process of the intersecting double cables. This more detailed step-by-step tensioning method effectively avoids the large errors that may occur when tensioning two cables at once. The tensioning sequence is as follows: cable group 5 → cable group 4 → cable group 3 → cable group 2 → cable group 1 → cable group 2 → cable group 3 → cable group 4 → cable group 5 → cable group 4 → cable group 3 → cable group 2 → cable group 1.

[0048] Furthermore, in step 3, the monitoring points for the strut-clip dual monitoring are arranged on the upper S2 and lower S3 struts on the side of cable group 1, and on the S1 strut in the middle span of cable group 1; on the upper T2 and lower T3 struts on the side of cable group 5 symmetrical to cable group 1, and on the T1 strut in the middle span of cable group 5; and on the Z1 strut in the middle span of cable group 3. Strain gauges are symmetrically arranged at the middle position of each monitoring point strut, and strain gauges are symmetrically arranged at the outer ear plates on both sides of each monitoring point strut. All strain gauges are electrically connected to the data acquisition box, and the acquisition box is electrically connected to the controller. During each stage of tensioning, the synchronicity of the verticality changes of all "strut + clamp" combinations must be ensured, and after all tensioning is completed, the final position of all "strut + clamp" combinations must reach the complete verticality of the design state. This ensures the accurate force transmission path, allows the cable force to be fully transmitted to the upper chord beam, and ensures that the camber of the structure meets the requirements. Therefore, strut-clip dual monitoring is set up simultaneously with tensioning. In strut axial force monitoring, two strain gauges are symmetrically attached to the left and right sides of the strut at its midpoint. The specific operation involves first attaching the strain gauges, then collecting the strain data measured by the gauges using a data acquisition box, and finally transmitting the data to a computer to display the real-time strain change curve. Simultaneously, professionals calculate the strut axial force based on the strain after each stage of tensioning for each cable group, and compare it with the design value. Firstly, by collecting data from two opposing strain gauges and observing their changes, the strut's position can be determined. When the two curves displayed on the computer show consistent trends, it indicates that the strut is maintaining a good vertical position. If the two curves show a large dispersion, it indicates that the strut may be tilted or subjected to eccentric loads. Secondly, relying solely on mid-span vertical displacement for tension monitoring and control is insufficient for the construction team to pinpoint the specific cause of tensioning failure. Insufficient displacement only indicates tensioning failure; adding an axial force monitoring network helps construction personnel determine whether the problem lies in the tensioning operation or the structural design. Among the five sets of cross-tensioned beams, measuring points were installed only on the sides of two sets: cable group 1 at the highest point of the roof and cable group 5 at the lowest point, as well as cable group 3 in the middle span. All five sets of tensioned beams share essentially the same design, materials, and construction techniques, exhibiting structural homogeneity. The selected three sets of monitoring points comprehensively cover the key and typical parts of the structure. While ensuring the monitoring objectives are achieved, this scheme significantly reduces instrument, installation, and data processing costs, meeting the requirements of engineering economics.

[0049] Furthermore, in step 3, if cable clamp deflection occurs due to unbalanced forces during tensioning, a cable clamp node correction scheme is selected to correct the cable clamp deflection.

[0050] Furthermore, in step 3, the cable clamp node correction scheme is as follows: by verifying the anti-slip bearing capacity of the cable clamp, the anti-slip bearing capacity of the cable clamp is compared with the design value of the cable force difference on both sides of the cable clamp to verify whether the anti-slip force of the cable clamp meets the specification requirements. Using the cable clamp specifications and bolt tightening force as test variables, multiple verifications are performed to finally obtain cable clamps whose anti-slip force meets the specification requirements. Then, the original X-shaped non-orthogonal cables are unloaded in stages, and the cable clamps in the original X-shaped non-orthogonal cables are replaced with cable clamps whose anti-slip force meets the specification requirements. Based on the verification results, the step-by-step and graded trial tensioning is reimplemented.

[0051] Furthermore, the verification process for replacing the cable clamp in step 3 is as follows: Based on the analysis results of the structure using the MidasGen finite element method, cable group 1 is identified as the cable group bearing the maximum cable force. The cable clamp with the largest difference in cable force between its two sides in cable group 1 is the clamp at the 1 / 2 span. The verification is performed using the clamp at the 1 / 2 span of cable group 1. This clamp is made of Q355C steel, with chamfered edges at the cable holes. The cable discs are connected by four M20-10.9S grade bolts. The design preload of the M20-10.9S grade bolts is 155kN, and the design value for the difference in cable force between the two sides of the clamp is 326.5kN.

[0052] Based on relevant standards such as the "Design Standard for Cable-stayed Structure Joints" (T / CECS1010-2022) and the "Design Standard for Steel Structures" (GB50017-2017), the anti-slip force is verified as follows: the sum of the effective tightening forces of all high-strength bolts on the cable clamp. for:

[0053]

[0054] in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts.

[0055] The anti-slip design load-bearing capacity of the cable clamp for:

[0056]

[0057] in, The coefficient of friction between the cable body and the cable clamp is 0.2 for a sealed cable with exposed steel wire. The safety factor for the anti-slip bearing capacity of the cable clamp is taken as 1.65. The anti-slip bearing capacity of the cable clamp is then compared. and the design value of the cable force difference on both sides of the cable clamp have to:

[0058]

[0059] Therefore, the slip resistance of the cable clamp at the 1 / 2 span of cable group 1 does not meet the specification requirements, and the cable clamp needs to be redesigned. Using larger cable clamps and higher bolt tightening force as variables, multiple calculations were performed, resulting in a cable clamp secured by eight M24-10.9S bolts. The design value of the M24-10.9S bolt preload is 225kN.

[0060] Based on relevant standards such as the "Design Standard for Cable-stayed Structure Joints" (T / CECS1010-2022) and the "Design Standard for Steel Structures" (GB50017-2017), the anti-slip force of the cable clamp secured by eight M24-10.9S bolts is verified as follows:

[0061] The sum of the effective tightening forces of all high-strength bolts on the cable clamp secured by eight M24-10.9S bolts is:

[0062]

[0063] in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts.

[0064] The anti-slip design load-bearing capacity of the cable clamp for:

[0065] Compare the anti-slip bearing capacity of the cable clamp and the design value of the cable force difference on both sides of the cable clamp. have to:

[0066]

[0067] After detailed design, the anti-slip force of the cable clamp secured by eight M24-10.9S bolts meets the specification requirements.

[0068] Furthermore, in step 3, the cable clamps at the 1 / 2 span of cable groups 1, 2, 3, 4 and 5 are replaced with cable clamps secured by eight M24-10.9S bolts.

[0069] It should be stated that the above-described specific embodiments are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art should understand that various modifications, equivalent substitutions, and variations can be made to the present invention. However, such variations, as long as they do not depart from the spirit of the present invention, should be within the scope of protection of the present invention. Furthermore, some terminology used in this specification and claims is not limiting, but merely for ease of description.

Claims

1. A construction method for an anti-slip X-shaped non-orthogonal tensioned cable structure roof, wherein the X-shaped non-orthogonal tensioned cable structure roof comprises an upper tensioned cable beam, a middle strut, and a lower cable, characterized in that, The upper and lower ends of the strut are respectively hinged to the tension beam and the cables through pins passing through pin holes. Each pair of cables in the 10 cables forms a group, and they are named cable group 1, cable group 2, cable group 3, cable group 4, and cable group 5 according to their position on the roof from highest to lowest. The roof construction method includes the following steps: Step 1: Upper tensioned beam hoisting: Assemble the struts and cable clamp cover plates on the ground, and then install them under the tensioned beam. Divide the roof into sections and install the upper tensioned beams with the struts and cable clamp cover plates installed according to the sections. Step 2, Cable Installation: Hoist and extend the cables, and install the cable clamps at the marked positions on the cable body. At the same time, install anti-slip devices at the connection between the cable clamps and the struts. Step 3, Cable Tensioning: A finite element model of the X-shaped non-orthogonal tensioned cable roof structure is established using Midas Gen to determine the step-by-step tensioning. Each level of tensioning should be carried out sequentially from cable group 5 to cable group 1. The fixed end cable head and the tensioning end cable head of each cable group are set on the same side. Single-sided synchronous tensioning is used to tension the cable groups. Two sets of tensioning equipment are used to apply prestress to the tensioning ends of the two cables in the same X-shaped non-orthogonal cable group on the same side. The tensioning is monitored by both struts and cable clamps.

2. The anti-slip construction method for cable clamp joints of roof tensioned structures according to claim 1, characterized in that, The anti-slip device mentioned in step 2 is a pad installed between the two sides of the cable clamp ear plate and the two sides of the outer ear plate of the support rod.

3. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 2, characterized in that, In step 3, the pre-tensioning target force is determined by the structural deformation control method. The two cables in each cable group are not arranged symmetrically. The pre-tensioning values ​​of the X-shaped cables are finally determined to be 400kN and 530kN, respectively. The step-by-step tensioning is a three-stage tensioning. Before the formal tensioning, it is necessary to pre-tighten with 5% of the pre-tensioning value. The tensioning forces of the three stages are 30%, 70%, and 100% of the design value, respectively.

4. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 3, characterized in that, In step 3, the monitoring points for the strut-clip dual monitoring are arranged on the upper S2 strut and lower S3 strut on the side of cable group 1, and on the middle S1 strut in the middle span of cable group 1, on the upper T2 strut and lower T3 strut on the side of cable group 5 symmetrical to cable group 1, on the middle T1 strut in the middle span of cable group 5, and on the middle Z1 strut in the middle span of cable group 3. Strain gauges are symmetrically arranged at the middle position of each monitoring point strut, and strain gauges are symmetrically arranged at the outer ear plates on both sides of each monitoring point strut. All strain gauges are electrically connected to the data acquisition box, and the acquisition box is electrically connected to the controller.

5. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 4, characterized in that, In step 3, if cable clamp deflection occurs due to unbalanced force during tensioning, a cable clamp node correction scheme is selected to correct the cable clamp deflection.

6. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 5, characterized in that, In step 3, the cable clamp node correction scheme is as follows: By verifying the anti-slip bearing capacity of the cable clamp, the anti-slip bearing capacity of the cable clamp is compared with the design value of the cable force difference on both sides of the cable clamp to verify whether the anti-slip force of the cable clamp meets the specification requirements. The cable clamp specifications and bolt tightening force are used as test variables to perform multiple verifications. Finally, the cable clamps whose anti-slip force meets the specification requirements are obtained. Then, the original X-shaped non-orthogonal cables are unloaded in stages, and the cable clamps in the original X-shaped non-orthogonal cables are replaced with cable clamps whose anti-slip force meets the specification requirements. Based on the verification results, the step-by-step and graded trial tensioning is carried out again.

7. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 6, characterized in that, The verification process for replacing the cable clamps in step 3 is as follows: Based on the analysis results of the structure using the MidasGen finite element method, cable group 1 is identified as the cable group bearing the maximum cable force. The cable clamp with the largest difference in cable force between its two sides in cable group 1 is the clamp at the 1 / 2 span. The verification is performed using the clamp at the 1 / 2 span of cable group 1. This clamp is made of Q355C steel, with chamfered edges at the cable holes. The cable discs are connected by four M20-10.9S grade bolts. The design preload of the M20-10.9S grade bolts is 155kN, and the design value for the difference in cable force between the two sides of the clamp is 326.5kN. Based on relevant standards such as the "Design Standard for Cable-stayed Structure Joints" (T / CECS1010-2022) and the "Design Standard for Steel Structures" (GB50017-2017), the anti-slip force is verified as follows: The sum of the effective tightening forces of all high-strength bolts on the cable clamp for: in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts. The anti-slip design load-bearing capacity of the cable clamp for: in, The coefficient of friction between the cable body and the cable clamp is 0.2 for a sealed cable with exposed steel wire. The safety factor for the anti-slip design bearing capacity of the cable clamp is taken as 1.

65. Comparison of the anti-slip bearing capacity of the cable clamp and the design value of the cable force difference on both sides of the cable clamp have to: Therefore, the slip resistance of the cable clamp at the 1 / 2 span of cable group 1 does not meet the specification requirements, necessitating a redesign of the cable clamp. Multiple calculations were performed using larger clamp sizes and higher bolt tightening forces as variables, resulting in a cable clamp secured with M24-10.9S bolts. The design preload of the M24-10.9S bolts is 225 kN. Based on relevant standards such as the "Design Standard for Cable-stayed Structure Joints" (T / CECS1010-2022) and the "Design Standard for Steel Structures" (GB50017-2017), the anti-slip force of the cable clamp secured by eight M24-10.9S bolts is verified as follows: The sum of the effective tightening forces of all high-strength bolts on the cable clamp secured by eight M24-10.9S bolts is: in, The fastening force loss coefficient for high-strength bolts is taken as 0.25; This is the sum of the design preload values ​​for all bolts. The anti-slip design load-bearing capacity of the cable clamp for: Comparison of the anti-slip bearing capacity of the cable clamp and the design value of the cable force difference on both sides of the cable clamp have to: After detailed design, the anti-slip force of the cable clamp secured by eight M20-10.9S bolts meets the specification requirements.

8. The construction method for the anti-slip X-shaped non-orthogonal tensioned cable structure roof according to claim 7, characterized in that, In step 3, the cable clamps at the 1 / 2 span of cable groups 1, 2, 3, 4 and 5 are replaced with cable clamps secured by eight M24-10.9S bolts.

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