Tension-compression cooperation rod piece structure, rectangular projection cable net and construction method of rectangular projection cable net

Abstract

The invention belongs to the technical field of cable net structures, and discloses a tension-compression cooperation rod piece structure, a rectangular projection cable net and a construction method of the rectangular projection cable net, a stable mechanical equilibrium relation is formed in the space through an auxiliary tension-compression rod set and a main force bearing rod set, and the whole structure is in a low-peak-value and wide-distribution stress state. Therefore, by constructing a parallelogram closed force bearing frame and introducing a multi-rod piece tension-compression cooperative stress mechanism, concentrated internal force at the corners of the rectangular ring truss is converted into axial force flow capable of being dispersed and transmitted from the force flow transmission path level, the force flow organization mode of the area is fundamentally improved, the maximum stress amplitude of a key part is remarkably reduced, and therefore the stress performance of the rectangular ring truss is improved. The overall stability and mechanical property of the structure are effectively improved, and the material consumption and construction complexity are reduced; under the working conditions of long-term prestress and repeated load, fatigue damage and local yield are effectively restrained, and the comprehensive application requirements of the large-span rectangular cable net structure in the aspects of safety, economical efficiency, durability and the like are met.

Description

Technical Field

[0001] This invention relates to the field of cable net structure technology, and in particular to a tension-compression co-link structure, a rectangular projection cable net, and its construction method. Background Technology

[0002] As architectural structures increasingly demand higher standards for spatial form and aesthetic expression, cable net structures have gained widespread attention due to their high efficiency in load-bearing and lightweight form. The core function of cable net structures lies in the synergistic effect of prestressed steel cables and geometric shape, efficiently transforming external loads into internal forces primarily composed of axial tension. This allows for lightweight coverage of large-span spaces, fully leveraging the superior tensile strength and high material utilization of steel cables. Consequently, they are widely used in large-span public buildings such as stadiums and cultural buildings. In a cable net structure system with a rectangular projection plane, the external ring truss, as the main boundary load-bearing component of the cable net, plays a crucial role in transferring the prestress of the cable net and external loads to the lower structure. The sharp corners of the rectangular cable net structure represent areas where geometric shape and boundary conditions abruptly change, causing a sharp turn in the force transmission path and making it difficult for the force flow to be continuous and uniformly distributed. When the cable net is prestressed or subjected to external loads, a large amount of cable force is concentrated in the sharp corner area and transferred to the corner of the ring truss. This causes the truss members in that area to bear large axial forces and additional bending moments at the same time, resulting in a significant stress concentration phenomenon. This becomes the most unfavorable and most vulnerable part of the structural system to local instability.

[0003] In traditional engineering practice, the stress concentration problem at the sharp corners of rectangular trusses is typically addressed by using rigid connections at the corners, combined with methods such as increasing member cross-sections, improving material strength, locally densifying or thickening members, adding stiffening ribs, or using small-curvature circular arc transition connections to enhance the load-bearing capacity of this area. However, these methods essentially passively resist concentrated internal forces by increasing the stiffness or strength of the components. While they can improve local load-bearing capacity to some extent, they do not fundamentally improve the force flow transmission characteristics. The result is often a significant increase in material usage, structural self-weight, and construction complexity. Furthermore, under long-term prestressing and repeated loading, high-stress zones can still easily form on the inner side of the sharp corners, inducing fatigue damage or local yielding. Overall, the cost-effectiveness is low, making it difficult to meet the comprehensive requirements of safety, economy, and durability for large-span rectangular cable net structures. Summary of the Invention

[0004] The purpose of this invention is to solve or at least alleviate some or all of the aforementioned problems. Therefore, the purpose of this invention is to provide a tension-compression co-linked member structure, a rectangular projected cable net, and its construction method, fundamentally improving the force flow organization in this area, achieving reasonable dispersion and transmission of internal forces, significantly reducing the maximum stress amplitude in key parts, and effectively improving the overall stability and mechanical properties of the structure, while reducing material usage and construction complexity. Under long-term prestressing and repeated loading conditions, it effectively suppresses fatigue damage and local yielding, thereby meeting the comprehensive application requirements of large-span rectangular cable net structures in terms of safety, economy, and durability.

[0005] To achieve this objective, the present invention adopts the following technical solution: A tension-compression co-supporting member structure is provided for supporting the corner region of a rectangular ring truss, the tension-compression co-supporting member structure comprising: The main load-bearing member group includes a first load-bearing member and a second load-bearing member; the adjacent sides of the corner of the rectangular ring truss respectively include a first main chord and a second main chord, the first main chord, the second main chord, the first load-bearing member and the second load-bearing member are connected to each other and enclose to form a closed load-bearing frame, and the projection shape of the closed load-bearing frame in the plane of the rectangular ring truss is a parallelogram. An auxiliary tension-compression rod assembly is installed within the closed load-bearing frame and connected to the main load-bearing rod assembly, the first main chord, and the second main chord. Together with the main load-bearing rod assembly, it forms a tension-compression synergistic force-bearing system to disperse the stress in the corner area of ​​the rectangular ring truss.

[0006] In some optional embodiments, the auxiliary tension / compression member group includes an auxiliary tension member group and an auxiliary compression member group, which are interconnected to divide the interior of the closed load-bearing frame into several sub-closed load-bearing frames; the projection shape of each sub-closed load-bearing frame in the plane of the rectangular ring truss is an isosceles triangle; the auxiliary tension member group is under tension when the structure is under stress, forming a tension transmission path in the corner region of the rectangular ring truss, and the auxiliary compression member group is under compression when the structure is under stress, forming a pressure transmission path in the corner region of the rectangular ring truss.

[0007] In some alternative embodiments, the auxiliary tie rod assembly includes a first tie rod arranged diagonally along the closed load-bearing frame, with one end connected to the connection node between the first load-bearing rod and the second load-bearing rod, and the other end connected to the connection node between the first main chord and the second main chord.

[0008] In some optional embodiments, the auxiliary tie rod assembly further includes two second tie rods, which are arranged symmetrically about the axis of the first tie rod; wherein, the two ends of one second tie rod are respectively connected to the center point of the first main chord and the center point of the first load-bearing rod; and the two ends of the other second tie rod are respectively connected to the center point of the second main chord and the center point of the second load-bearing rod.

[0009] In some alternative embodiments, the auxiliary pressure bar assembly includes four inclined pressure bars, one end of each of the four inclined pressure bars is connected to the axial center position of the first tie rod, and the other end of each of the four inclined pressure bars is connected to the two end connection nodes of the two second tie rods respectively.

[0010] In some alternative embodiments, the auxiliary tension / compression rod group and the main load-bearing rod group are made of the same material as the main component of the rectangular ring truss.

[0011] In some alternative embodiments, the cross-sectional shape and size of the auxiliary tension / compression rod group and the main load-bearing rod group are consistent with the cross-sectional shape and size of the main component of the rectangular ring truss.

[0012] In some alternative embodiments, the main load-bearing rod group, the auxiliary tension / compression rod group, the first main chord, and the second main chord are hinged together.

[0013] A rectangular projection cable net includes a rectangular ring truss and at least four tension-compression coordinating member structures as described in any of the above, wherein the at least four tension-compression coordinating member structures are respectively fixedly installed at the four corners of the rectangular ring truss.

[0014] A method for constructing a rectangular projection cable net, used for constructing the corner areas of a rectangular projection cable net as described above, includes the following steps: S1: Perform integrated 3D modeling and digital layout of the rectangular ring truss and the tension-compression coordinated member structure. Based on the modeling results, cut, process, and manufacture the first main chord, the second main chord, the first load-bearing member, the second load-bearing member, and the auxiliary tension-compression member group. Based on the 3D model, perform digital simulation pre-assembly to verify the dimensional matching relationship and connection accuracy between the components. After the pre-assembly verification is completed, each component is uniquely identified and shipped. S2: Transport the rectangular ring truss and the tension-compression co-supporting member structure to the construction site, and first complete the overall installation of the main body of the rectangular ring truss; then, hoist the prefabricated tension-compression co-supporting member structure to the corner area of ​​the rectangular ring truss for interlocking installation; during the installation process, first connect the first main chord and the second main chord of the adjacent sides of the corner of the rectangular ring truss to the first load-bearing member and the second load-bearing member in the main load-bearing member group respectively to form the closed load-bearing frame; then install the auxiliary tension-compression member group and initially tension the auxiliary tension-compression member group so that the closed load-bearing frame forms a tension-compression co-supporting force system; S3: Finally tighten all connection nodes of the closed load-bearing frame and the auxiliary tension and compression rod group, and perform structural reinforcement treatment on the key stress concentration parts in the corner area; S4: Perform prestressing tensioning and structural stability testing on the installed rectangular projection cable net. Apply prestress step by step using intelligent tensioning equipment according to the designed tensioning conditions to simulate the actual internal forces corresponding to the corners of the rectangular ring truss gradually borne by the tension-compression coordinated member structure. At each tensioning level, detect the measured internal force values ​​of each member in the main load-bearing member group and the auxiliary tension-compression member group, and calculate their deviation from the theoretical design internal force. When the internal force deviation of any member exceeds 15% of the theoretical design value, perform dynamic feedback adjustment by adjusting the tensioning force of the adjacent auxiliary tension-compression member group. When the internal force deviation of each member does not exceed 15% of the theoretical design value, proceed to the next tensioning level until all designed tensioning conditions are completed, and the deviation between the measured internal force of each member and the theoretical design internal force does not exceed 20%, and the overall force balance requirement is met.

[0015] The beneficial effects of this invention are: This invention provides a tension-compression synergistic member structure, a rectangular projected cable net, and its construction method. By establishing a stable mechanical equilibrium between the auxiliary tension-compression member group and the main load-bearing member group in space, the stress no longer peaks at the sharp corners of the rectangular projected cable net, resulting in a low-peak, widely distributed stress state for the overall structure. Thus, by constructing a parallelogram closed load-bearing frame and introducing a multi-member tension-compression synergistic force mechanism, the concentrated internal forces at the corners of the rectangular ring truss are transformed into dispersed and transferable axial force flows at the force flow transmission path level. This fundamentally improves the force flow organization in this area, significantly reduces the maximum stress amplitude in key parts, and effectively enhances the overall structural stability and mechanical performance while reducing material usage and construction complexity. Under long-term prestressing and repeated loading conditions, it effectively suppresses fatigue damage and local yielding, thereby meeting the comprehensive application requirements of large-span rectangular cable net structures in terms of safety, economy, and durability. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0017] Figure 1 This is a structural schematic diagram of the corner region of the rectangular ring truss described in this invention; Figure 2 This is a partial assembly drawing of the tension-compression coordinated member structure described in this invention at the corner position of a rectangular ring truss; Figure 3 It is the tension-compression coordinated rod structure described in this invention; Figure 4 This is a schematic diagram of the rectangular projection cable net described in this invention; Figure 5 This is a flowchart of the rectangular projection cable net construction method described in this invention.

[0018] In the picture: 1. Rectangular ring truss; 11. First main chord; 12. Second main chord; 2. Main load-bearing member group; 21. First load-bearing member; 22. Second load-bearing member; 3. Auxiliary tension and compression member group; 31. Auxiliary tie member group; 311. First tie member; 312. Second tie member; 32. Auxiliary compression member group; 321. Diagonal compression member. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] In this invention, the terms "comprising," "including," "having," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0021] In this invention, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, in this invention, the character " / " generally indicates that the preceding and following related objects have an "and / or" relationship.

[0022] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," "fixed," "combined," "coupled," and "installed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection via an intermediate medium; or the internal communication of two components or the interaction between two components. As examples, a direct connection refers to two parts or components being connected together without the need for an intermediate medium, while an indirect connection refers to two parts or components each being connected to at least one intermediate medium, with the connection achieved through the intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Furthermore, "connected" and "coupled" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0023] In this invention, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the value and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​not using relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0024] In this invention, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0025] In this invention, the terms "upper," "lower," "left," "right," "front," and "rear," etc., refer to the orientations or positional relationships shown in the accompanying drawings. They are used solely for ease of description and simplification of operation, 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, they should not be construed as limitations on this invention. Furthermore, in the context, it should be understood that when an element is mentioned as being "upper" or "lower" than another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as "upper side," "lower side," "left side," "right side," "front side," and "rear side" not only represent positive orientation but can also be understood as lateral orientation. For example, "above," "on top of," "upper side of," and "above" the first feature "above" or "on the second feature" includes the first feature being directly above, to the upper left, to the upper right, to the upper front, and to the upper rear of the second feature, or simply indicating that the first feature is at a higher horizontal level than the second feature. The terms "below," "under," "below," and "below" for "first feature" and "second feature" include situations where the first feature is directly below, to the lower left, to the lower right, in front of, or behind the second feature, or simply indicate that the first feature is at a lower horizontal level than the second feature. Furthermore, the terms "first" and "second" are used merely for descriptive distinction and have no specific meaning.

[0026] Please refer to Figures 1 to 4 As shown, this embodiment provides a tension-compression coordinated member structure for supporting the corner region of a rectangular ring truss 1. It includes a main load-bearing member group 2 and an auxiliary tension-compression member group 3. The main load-bearing member group 2 includes a first load-bearing member 21 and a second load-bearing member 22. Adjacent sides of the corner of the rectangular ring truss 1 include a first main chord member 11 and a second main chord member 12. The first main chord member 11, the second main chord member 12, the first load-bearing member 21, and the second load-bearing member 22 are interconnected and enclose a closed load-bearing frame. The projection of the closed load-bearing frame onto the plane of the rectangular ring truss 1 is a parallelogram. The auxiliary tension-compression member group 3 is disposed within the closed load-bearing frame and connected to the main load-bearing member group 2, the first main chord member 11, and the second main chord member 12. Together with the main load-bearing member group 2, it constitutes a tension-compression coordinated force-bearing system to disperse the stress in the corner region of the rectangular ring truss 1.

[0027] like Figure 1As shown, since the rectangular ring truss 1 forms a typical force flow abrupt change point at the corner, the axial forces of the first main chord 11 and the second main chord 12 change direction sharply at the sharp corner, easily forming significant stress concentration in the inner region of both. To address the above problem, this embodiment connects the first main chord 11, the second main chord 12, the first load-bearing member 21, and the second load-bearing member 22 to form a closed load-bearing frame. The projection of this closed load-bearing frame onto the plane of the rectangular ring truss 1 is a parallelogram, which allows the force flow that originally changed abruptly at the corner node to continuously transfer along the boundary of the parallelogram. This allows the internal forces concentrated at the corner node to form a circumferential transmission path within the closed load-bearing frame, thereby transforming the corner from a traditional force convergence node into a force diversion node. Meanwhile, the auxiliary tension / compression member group 3 is set inside the closed load-bearing frame and is connected to the main load-bearing member group 2, the first main chord 11, and the second main chord 12 respectively. During the stress process, it participates in the internal force transmission in the corner area and together with the main load-bearing member group 2, it forms a multi-path tension / compression cooperative force-bearing system. Through this structural arrangement, the concentrated internal force at the corner of the rectangular ring truss 1 is decomposed and distributed to multiple tension and compression paths. Different members can automatically enter the tension or compression working state according to the actual working conditions, so that the internal force can be adaptively distributed among multiple members, avoiding a single member bearing extreme internal force, thereby forming a stable force-bearing unit with truss characteristics in the corner area.

[0028] Under the aforementioned tension-compression synergistic member structure, the auxiliary tension-compression member group 3 and the main load-bearing member group 2 form a stable mechanical equilibrium relationship in space, so that the stress no longer forms a peak on the inside of the sharp corner, and the overall structure exhibits a low-peak, widely distributed stress state. Thus, by constructing a parallelogram closed load-bearing frame and introducing a multi-member tension-compression synergistic force mechanism, the concentrated internal force at the corner of the rectangular ring truss 1 is transformed into a dispersed and transferable axial force flow from the perspective of force flow transmission path. This fundamentally improves the stress state at the corner, avoids passive enhancement of the stiffness or strength of local components, eliminates stress singularities at the corner, significantly improves material utilization efficiency, and is conducive to improving the overall safety and durability of the structure.

[0029] Specifically, the auxiliary tension / compression member group 3 includes an auxiliary tension member group 31 and an auxiliary compression member group 32. The auxiliary tension member group 31 and the auxiliary compression member group 32 are interconnected, dividing the interior of the closed load-bearing frame into several sub-closed load-bearing frames. The projection shape of each sub-closed load-bearing frame in the plane of the rectangular ring truss 1 is an isosceles triangle. The auxiliary tension member group 31 is under tension when the structure is under stress, forming a tension transmission path in the corner area of ​​the rectangular ring truss 1. The auxiliary compression member group 32 is under compression when the structure is under stress, forming a pressure transmission path in the corner area of ​​the rectangular ring truss 1. Among them, the triangle is the most geometrically stable basic force unit. The isosceles triangle configuration gives the force path good geometric symmetry and stability, thus enabling the overall force system in the corner region to evolve from a parallelogram closed load-bearing frame into a combination of multiple triangular stable mechanical units. This achieves triangular decomposition and directional transmission of tension and compression forces in the corner, transforming the corner force from a concentrated, coupled state to a multi-path, axial force-dominated stable force system, significantly suppressing corner structural deformation and uncontrolled redistribution of internal forces. Since the auxiliary tension and compression members together form multiple sub-closed load-bearing frames, each sub-closed load-bearing frame forms a local force balance. The overall internal force in the corner is decomposed step by step and transmitted in multiple triangular units, avoiding the concentration of internal forces in a single node or single member. This is equivalent to constructing a multi-level force flow buffer, diversion, and closed force transmission system in the corner region, thereby eliminating potential weak points in the force distribution. Furthermore, the auxiliary tie rod group 31 operates under tension when the structure is under stress, with the tensile force continuously transmitted along the direction of the auxiliary tie rod, forming a tensile force transmission path in the corner region. The auxiliary compression rod group 32 operates under compression when the structure is under stress, with the compressive force stably closed along the direction of the auxiliary compression rod, forming a compressive force transmission path in the corner region. This allows the tensile and compressive force flows to form clear and independent force transmission channels within each sub-closed load-bearing frame, significantly reducing the stress peak on the inner side of the sharp corner. Multiple sub-closed load-bearing frames operate in parallel, and any abnormal internal force in any member can be shared by adjacent units. The corner region no longer relies on the ultimate bearing capacity of a single member, reducing reliance on passive reinforcement methods such as thickened members and stiffeners.

[0030] like Figure 2 and Figure 3As shown, more specifically, the auxiliary tie rod group 31 includes a first tie rod 311, which is arranged diagonally along the closed load-bearing frame. One end of the first tie rod 311 is connected to the connection node between the first load-bearing rod 21 and the second load-bearing rod 22, and the other end is connected to the connection joint between the first main chord 11 and the second main chord 12. This allows the first tie rod 311 to form a diagonal tension transmission channel that runs through the corner region under structural stress. Under the load of the rectangular ring truss 1, the axial force of the closed load-bearing frame changes direction at the corner. The first tie rod 311 mainly bears the axial tension, and the generated tension component can be directly received by the first tie rod 311 and transmitted along its axis. This avoids the tension from concentrating or abruptly changing at the corner node, reduces the bending moment, shear force, and secondary stress at the node, and improves the controllability of the force on the members and nodes.

[0031] In some embodiments, the auxiliary tie rod assembly 31 further includes two second tie rods 312, which are symmetrically arranged about the axis of the first tie rod 311. One second tie rod 312 is connected at both ends to the center points of the first main chord 11 and the first load-bearing member 21, respectively; the other second tie rod 312 is connected at both ends to the center points of the second main chord 12 and the second load-bearing member 22, respectively. By symmetrically arranging the two second tie rods 312 about the axis of the first tie rod 311, the tensile force components in the corner region are geometrically decomposed symmetrically. Under structural stress, the tensile force transmitted to the corner region by each main chord and load-bearing member is symmetrically decomposed and then axially transmitted along the two second tie rods 312 and the first tie rod 311, and guided into the closed load-bearing frame. This avoids the concentration of tensile force along a single diagonal path, thereby forming multiple symmetrical tensile force transmission paths in the corner region, significantly reducing the stress peak at the connection nodes between each main chord and load-bearing member. Furthermore, two second tie rods 312 are respectively connected to the center points of the first main chord 11, the second main chord 12, the first load-bearing rod 21, and the second load-bearing rod 22, so that the tension acts directly on the vicinity of the axis of the corresponding rod, reducing the eccentric effect of the tension on the end nodes of the rods, reducing the bending moment at the end of the rods and the additional internal forces at the nodes, making the stress state of the main chords and load-bearing rods closer to pure axial force, thereby effectively avoiding the problem of local stress concentration caused by the concentration of tension at the corner of the node. By distributing the corner tension in parallel with multiple tie rods, each tie rod automatically diverts the stress, reducing the stress amplitude under repeated loading, reducing the risk of fatigue damage, and improving the overall safety and durability of the corner force-bearing system.

[0032] In some embodiments, the auxiliary compression member group 32 includes four inclined compression members 321. One end of each of the four inclined compression members 321 is connected to the axial center of the first tie rod 311, and the other end of each of the four inclined compression members 321 is connected to the two end connection nodes of the two second tie rods 312, respectively. By setting a pressure convergence node at the center of the first tie rod 311 and radiating the four inclined compression members 321 outward from this node, the pressure components transmitted to the corner area by each main chord, each load-bearing member, and the auxiliary compression member group 31 can be concentrated at the central node and decomposed into multiple symmetrical axial pressure transmission paths under structural stress. This avoids pressure concentration on a single component or node, reduces the risk of corner pressure concentration, and improves the overall stability of the corner stress system.

[0033] Because the structural design of the auxiliary tension / compression member group 3 and the main load-bearing member group 2 can reasonably disperse and transfer the stress in the corner area of ​​the rectangular ring truss 1, significantly reducing the maximum stress amplitude in critical parts, in order to reduce material usage and construction complexity, in some embodiments, the material type of the auxiliary tension / compression member group 3 and the main load-bearing member group 2 is the same as that of the main components of the rectangular ring truss 1. By using uniform materials, the auxiliary tension / compression member group 3 and the main load-bearing member group 2 are consistent with the main components of the rectangular ring truss 1 in terms of elastic modulus, yield strength, and deformation characteristics. When the structure is under stress, each member can deform synchronously and bear the load collaboratively, ensuring that the corner stress is evenly distributed along the design path and avoiding local overload or stress imbalance caused by differences in material stiffness. At the same time, uniform materials facilitate the standardization of construction processes, such as consistent welding, bolting connections, or joint treatment methods, reducing construction complexity, facilitating on-site installation and quality control, and reducing the difficulty of material management and procurement.

[0034] Furthermore, the cross-sectional shape and size of the auxiliary tension and compression rod group 3 and the main load-bearing rod group 2 are consistent with the cross-sectional shape and size of the main component of the rectangular ring truss 1, which reduces the types and quantities of materials with different cross-sections and realizes the batch use of materials. The unified cross-section not only reduces material costs, but also facilitates project management and inventory control. At the same time, with the reasonable corner stress dispersion design, an economical and efficient structural solution is achieved under the premise of ensuring structural safety and load-bearing capacity.

[0035] Specifically, the auxiliary tension / compression member group 3, the main load-bearing member group 2, and the rectangular ring truss 1 all use Q235 steel with a hollow circular tube section, 10mm thick and 273mm in diameter, ensuring that the corner tension / compression coordinating member structure maintains consistency with the main structure of the rectangular ring truss 1 in terms of material properties and cross-sectional stiffness. This cross-sectional shape has high axial load-bearing efficiency and uniform cross-sectional stress characteristics, which is conducive to the stable axial transmission of tension and compression, avoiding local stress concentration caused by abrupt changes in cross-section or stiffness mismatch. At the same time, the hollow circular tube section has high cross-sectional inertia efficiency and low self-weight while ensuring load-bearing capacity, which helps to reduce the overall structural weight and improve material utilization. Q235 steel has moderate strength, good plasticity and ductility, and can adapt to prestressing tension and long-term repeated loading, improving the safety and durability of the structure.

[0036] In some embodiments, the main load-bearing rod group 2, the auxiliary tension-compression rod group 3, the first main chord 11, and the second main chord 12 are hinged together. During the corner stress process, the members of the main load-bearing rod group 2 and the auxiliary tension-compression rod group 3 may be in tension or compression respectively. The hinged connection can ensure that each member automatically bears the force flow along its axial direction, realize the coordinated work of tension and compression, and prevent uneven force distribution or premature yielding of some members due to excessive node stiffness. This allows each member to mainly bear the axial tension and compression without generating additional bending moment, realizing the dispersion and multi-path transmission of internal forces at the corner, while simplifying node processing and construction, and improving the overall stability and economy of the structure.

[0037] Optionally, the main load-bearing member group 2, the auxiliary tension / compression member group 3, the first main chord member 11, and the second main chord member 12 are hingedly connected by bolts. High-strength bolts are tightened in three steps—initial tightening, secondary tightening, and final tightening—using a torque wrench to precisely control the preload and stiffness of the nodes. This ensures the necessary stability of each node under structural stress while maintaining that each member primarily bears axial tension and compression. It also ensures that the tension / compression coordinating member structure in the corner area can distribute and transmit internal forces according to the designed path, improving structural safety, construction controllability, and maintenance convenience.

[0038] like Figure 4As shown, this embodiment also provides a rectangular projection cable net, including a rectangular ring truss 1 and at least four tension-compression co-working member structures as described in any of the above embodiments. The at least four tension-compression co-working member structures are respectively fixedly installed at the four corners of the rectangular ring truss 1. When the rectangular projection cable net is prestressed or subjected to external loads, the corner key members, which were originally primarily under compression, are reconstructed into a tension-compression co-working force system. This forms a spatial force network in the corner area, distributing and transmitting forces outwards and to adjacent areas, allowing some auxiliary members to bear tension. This transforms the original single compression force mode into a tension-compression co-working mode, thus reducing the original force flow in the corner area. The stress distribution point is effectively mitigated, fundamentally improving the force flow organization in the area. Through multiple tension-compression coordinating members, the stress is rationally dispersed and transmitted, forming a multi-path axial force transmission, significantly reducing the maximum stress amplitude in key areas, and resulting in a more uniform internal force distribution. This avoids the local high stress phenomenon caused by stress concentration in traditional structures, effectively improving the overall stability and mechanical properties of the structure, and reducing material usage and construction complexity. Under long-term prestressing and repeated loading conditions, it effectively suppresses fatigue damage and local yielding, thus meeting the comprehensive application requirements of large-span rectangular cable net structures in terms of safety, economy, and durability.

[0039] like Figure 5 As shown, this embodiment also provides a method for constructing a rectangular projection cable net, used for constructing the corner area of ​​the rectangular projection cable net in the above embodiment, including the following steps: S1: Perform integrated 3D modeling and digital layout of the rectangular ring truss 1 and the tension-compression coordinated member structure. Based on the modeling results, cut, process and manufacture the first main chord 11, the second main chord 12, the first load-bearing member 21, the second load-bearing member 22 and the auxiliary tension-compression member group 3. Based on the 3D model, perform digital simulation pre-assembly to verify the dimensional matching relationship and connection accuracy between the components. After the pre-assembly verification is completed, each component is uniquely identified and shipped. S2: Transport the rectangular ring truss 1 and the tension-compression co-supporting member structure to the construction site, and first complete the overall installation of the main body of the rectangular ring truss 1; then, hoist the prefabricated tension-compression co-supporting member structure to the corner area of ​​the rectangular ring truss 1 for interlocking installation; during the installation process, first connect the first main chord 11 and the second main chord 12 of the adjacent sides of the corner of the rectangular ring truss 1 to the first load-bearing member 21 and the second load-bearing member 22 in the main load-bearing member group 2 respectively to form a closed load-bearing frame; then install the auxiliary tension-compression member group 3 and initially tension the auxiliary tension-compression member group 3 so that the closed load-bearing frame forms a tension-compression co-supporting force system; S3: Final tightening of all connection nodes of the closed load-bearing frame and auxiliary tension / compression rod group 3, and structural reinforcement treatment of key stress concentration areas in the corner region; S4: Perform prestressing tensioning and structural stability testing on the installed rectangular projection cable net. Apply prestress step by step using intelligent tensioning equipment according to the designed tensioning conditions to simulate the tension-compression coordinated member structure gradually bearing the actual internal forces corresponding to the corners of the rectangular ring truss 1. At each tensioning level, detect the measured internal force values ​​of each member in the main load-bearing member group 2 and the auxiliary tension-compression member group 3, and calculate their deviation from the theoretical design internal force. When the internal force deviation of any member exceeds 15% of the theoretical design value, perform dynamic feedback adjustment by adjusting the tensioning force of the adjacent auxiliary tension-compression member group 3. When the internal force deviation of each member does not exceed 15% of the theoretical design value, proceed to the next tensioning level until all designed tensioning conditions are completed, and the deviation between the measured internal force of each member and the theoretical design internal force does not exceed 20%, and the overall force balance requirement is met.

[0040] Through integrated 3D modeling, digital layout, and pre-assembly verification, component dimensional deviations and connection accuracy issues can be identified before construction, avoiding on-site adjustments and improving component processing and installation accuracy. Simultaneously, unique identification of components facilitates rapid on-site identification and positioning, reducing assembly errors and improving construction efficiency. During construction, a closed load-bearing frame is first installed, forming a closed load-bearing frame with the first main chord 11, second main chord 12, first load-bearing member 21, and second load-bearing member 22. Then, the prefabricated auxiliary tension / compression member assembly 3 is hoisted and initially tensioned, ensuring the corner areas form the expected tension / compression synergistic force-bearing system. The interlocking installation of the main load-bearing member assembly 2 and the auxiliary tension / compression member assembly 3 ensures that the geometric positions and connection relationships of each member strictly conform to design requirements, reducing on-site errors.

[0041] Subsequently, prestress was applied step by step according to the designed tensioning conditions, gradually subjecting each member to the designed internal forces and simulating the actual working state. During the tensioning process, the internal forces of each member were monitored in real time. When the measured internal force deviation of any member exceeded the allowable value, timely feedback adjustment was made by adjusting the tension of the adjacent auxiliary tension-compression rod group 3 to ensure that the force on each member was close to the theoretical design value, avoiding local overload or uneven stress. The step-by-step tensioning and internal force monitoring worked in tandem to ensure that each member always maintained a balanced force, reducing the risk of fatigue and local buckling, and ultimately forming a tension-compression synergistic system composed of a closed load-bearing frame and the auxiliary tension-compression rod group 3, achieving multi-path distributed force transmission.

[0042] By employing prefabricated components and on-site hoisting, splicing operations are reduced, lowering construction risks. Combined with digital monitoring and dynamic adjustments, structural stress is controllable, ensuring construction safety and reliable final structural performance. Simultaneously, this construction method reduces on-site rework, material waste, and construction time, improving project efficiency and economy. Furthermore, stress balancing reduces reliance on locally thickened members or additional stiffening measures, further saving material costs.

[0043] Specifically, the tensioning process adopts an overall graded and zoned synchronous tensioning method, with the uniformity of internal force distribution as the control target and the change of internal force in the corner area of ​​the member as the feedback basis to dynamically adjust the tensioning process.

[0044] More specifically, the prestressing tensioning process can be divided into three tensioning levels: 30%, 70%, and 100%. Static monitoring is performed after each tensioning level to obtain the actual internal force distribution of each member in the corner region. When the monitoring results show that the measured variance of the internal force in the corner members exceeds 15% of the theoretically calculated value, dynamic feedback adjustment is implemented by fine-tuning the prestress of adjacent cable segments by ±5%, thereby guiding the redistribution of internal forces. This tensioning method aims to optimize the uniformity of internal forces in the corner members, rather than simply terminating when the cable force reaches the nominal value, thus realizing a graded tensioning control method guided by internal force distribution.

[0045] Optionally, the intelligent tensioning equipment uses a through-hole hydraulic jack as the tensioning execution unit. The mechanical parameter acquisition unit on the through-hole hydraulic jack measures the tension force of each cable segment and the axial force of the corner members in real time, and transmits the data to the control unit for real-time analysis. The control unit calculates the feedback adjustment amount based on the deviation between the preset design internal force value and the actual internal force, and issues a fine-tuning command (e.g., ±5%) to the through-hole hydraulic jack to achieve graded and zoned synchronous tensioning. After each stage of tensioning is completed, the equipment automatically stops for monitoring to determine whether the internal force of the corner members meets the equilibrium requirements. If the deviation exceeds a threshold, the system automatically performs fine-tuning until the internal force distribution approaches the design value. Through this closed-loop control, intelligent tensioning guided by internal force distribution is achieved, improving the uniformity of structural stress and construction safety, while reducing the risk of human intervention and errors.

[0046] Through experimental comparative analysis, under the same rectangular projection cable net structure and the same material parameters, the construction process of this embodiment is used to install tension-compression coordinated member structures in the corner area. Compared with the traditional construction method (by increasing the member cross-section, improving material strength, locally densifying or thickening the members and using rigid connections), the stress conditions of each member are as follows: In traditional construction methods, under 10kN prestressing of cable segments, the corner truss of a rectangular projected cable net structure exhibits significant internal force concentration, with the upper members primarily under compression and the lower members primarily under tension. Analysis shows that the maximum compressive force borne by the upper key members is 78.52kN, and the maximum tensile force borne by the lower key members is 58.97kN. Furthermore, the internal force distribution in the corner region exhibits significant dispersion, with a variance of 505.85 for absolute internal forces, indicating uneven stress distribution and pronounced local stress concentration in this area. This necessitates increasing the cross-section or improving material strength to meet load-bearing requirements.

[0047] In contrast, the tension-compression co-contraction member structure of this embodiment reconstructs the corner critical members, which were originally mainly under compression, into a force system that works in a coordinated tension-compression manner. This creates a spatial force network in the corner region, weakening the tendency of internal forces to concentrate at the corner points in traditional structures and enabling a multi-path tension-compression force transmission mechanism in the corner region. Analysis results show that under the same 10kN cable segment prestress, the maximum compressive force of the upper critical compression member is reduced to 47.05kN, a reduction of approximately 40.1% compared to traditional construction methods; the maximum tensile force of the lower critical tension member is adjusted to 43.51kN, a reduction of approximately 26.2% compared to traditional methods. Simultaneously, the variance of the absolute value of the internal forces in the corner critical members decreases to 200.9, a reduction of approximately 60.3% compared to traditional structures, indicating a more uniform distribution of internal forces, reducing the peak internal forces of critical members, making the tension and compressive stress amplitudes more similar, and improving the overall structural stability and safety reserve. This structural form has significant advantages in the corner optimization design of large-span rectangular cable net structures.

[0048] Therefore, it is evident that by installing a rectangular projected cable net structure with tension-compression co-contraction members, the stress peak and internal force dispersion in the corner region of the rectangular cable net are significantly reduced without increasing the cross-sectional dimensions of the members or improving the material strength, effectively alleviating the corner stress concentration problem. This result demonstrates that, compared to traditional construction methods that rely on adding materials and stiffness, this embodiment has significant advantages in terms of stress rationality, material utilization efficiency, and overall structural safety.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A tension-compression co-supporting member structure for supporting the corner region of a rectangular ring truss (1), characterized in that, The tension-compression coordinated member structure includes: The main load-bearing rod group (2) includes a first load-bearing rod (21) and a second load-bearing rod (22); the adjacent sides of the corner of the rectangular ring truss (1) respectively include a first main chord rod (11) and a second main chord rod (12). The first main chord rod (11), the second main chord rod (12), the first load-bearing rod (21) and the second load-bearing rod (22) are connected to each other and enclose to form a closed load-bearing frame. The projection shape of the closed load-bearing frame in the plane of the rectangular ring truss (1) is a parallelogram. The auxiliary tension and compression rod group (3) is set in the closed load-bearing frame and is connected to the main load-bearing rod group (2), the first main chord (11) and the second main chord (12). Together with the main load-bearing rod group (2), it forms a tension and compression cooperative force system to disperse the stress in the corner area of ​​the rectangular ring truss (1).

2. The tension-compression co-link structure according to claim 1, characterized in that, The auxiliary tension and compression rod group (3) includes an auxiliary tie rod group (31) and an auxiliary compression rod group (32). The auxiliary tie rod group (31) and the auxiliary compression rod group (32) are connected to each other, dividing the interior of the closed load-bearing frame into several sub-closed load-bearing frames. The projection shape of each sub-closed load-bearing frame in the plane of the rectangular ring truss (1) is an isosceles triangle. The auxiliary tie rod group (31) is under tension when the structure is under stress, forming a tension transmission path in the corner area of ​​the rectangular ring truss (1). The auxiliary compression rod group (32) is under compression when the structure is under stress, forming a pressure transmission path in the corner area of ​​the rectangular ring truss (1).

3. The tension-compression co-link structure according to claim 2, characterized in that, The auxiliary tie rod group (31) includes a first tie rod (311), which is arranged diagonally along the closed load-bearing frame. One end of the first tie rod (311) is connected to the connection node between the first load-bearing rod (21) and the second load-bearing rod (22), and the other end is connected to the connection node between the first main chord rod (11) and the second main chord rod (12).

4. The tension-compression co-link structure according to claim 3, characterized in that, The auxiliary tie rod assembly (31) further includes two second tie rods (312), which are arranged symmetrically about the axis of the first tie rod (311). One of the second tie rods (312) is connected at both ends to the center points of the first main chord (11) and the first load-bearing rod (21), respectively. The other second tie rod (312) is connected at both ends to the center points of the second main chord (12) and the second load-bearing rod (22), respectively.

5. The tension-compression co-link structure according to claim 4, characterized in that, The auxiliary pressure bar assembly (32) includes four inclined pressure bars (321). One end of each of the four inclined pressure bars (321) is connected to the axial center of the first tie rod (311), and the other end of each of the four inclined pressure bars (321) is connected to the two end connection nodes of the two second tie rods (312).

6. The tension-compression co-link structure according to any one of claims 1-5, characterized in that, The auxiliary tension / compression rod group (3) and the main load-bearing rod group (2) are made of the same material as the main components of the rectangular ring truss (1).

7. The tension-compression co-link structure according to claim 6, characterized in that, The cross-sectional shape and size of the auxiliary tension and compression rod group (3) and the main load-bearing rod group (2) are consistent with the cross-sectional shape and size of the main component of the rectangular ring truss (1).

8. The tension-compression co-link structure according to claim 1, characterized in that, The main load-bearing rod group (2), the auxiliary tension and compression rod group (3), the first main chord rod (11), and the second main chord rod (12) are hinged together.

9. A rectangular projection cable net, characterized in that, It includes a rectangular ring truss (1) and at least four tension-compression co-link structures as described in any one of claims 1-8, wherein the at least four tension-compression co-link structures are respectively fixedly installed at the four corners of the rectangular ring truss (1).

10. A method for constructing a rectangular projection cable net, characterized in that, The construction of the corner region of the rectangular projection cable net as described in claim 9 includes the following steps: S1: Perform integrated three-dimensional modeling and digital layout of the rectangular ring truss (1) and the tension-compression coordinated member structure. Based on the modeling results, cut, process and cut the first main chord (11), the second main chord (12), the first load-bearing member (21), the second load-bearing member (22) and the auxiliary tension-compression member group (3). Based on the three-dimensional model, perform digital simulation pre-assembly to verify the size matching relationship and connection accuracy between the components. After the pre-assembly verification is completed, each component is uniquely identified and shipped. S2: Transport the rectangular ring truss (1) and the tension-compression co-supporting member structure to the construction site, and first complete the overall installation of the main body of the rectangular ring truss (1); then, hoist the prefabricated tension-compression co-supporting member structure to the corner area of ​​the rectangular ring truss (1) for interlocking installation; during the installation process, first connect the first main chord (11) and the second main chord (12) of the adjacent sides of the corner of the rectangular ring truss (1) to the first load-bearing member (21) and the second load-bearing member (22) in the main load-bearing member group (2) respectively to form the closed load-bearing frame; then install the auxiliary tension-compression member group (3) and initially tension the auxiliary tension-compression member group (3) so that the closed load-bearing frame forms a tension-compression co-supporting force system; S3: Finally tighten each connection node of the closed load-bearing frame and the auxiliary tension and compression rod group (3), and perform structural reinforcement treatment on the key stress concentration parts in the corner area; S4: Perform prestressing tensioning and structural stability testing on the installed rectangular projection cable net. Apply prestress step by step through intelligent tensioning equipment according to the designed tensioning conditions to simulate the actual internal forces corresponding to the corners of the rectangular ring truss (1) gradually borne by the tension-compression coordinated member structure. At each tensioning level, detect the measured internal force values ​​of each member in the main load-bearing member group (2) and the auxiliary tension-compression member group (3), and calculate their deviation from the theoretical design internal force. When the internal force deviation of any member exceeds 15% of the theoretical design value, perform dynamic feedback adjustment by adjusting the tensioning force of the adjacent auxiliary tension-compression member group (3). When the internal force deviation of each member does not exceed 15% of the theoretical design value, proceed to the next level of tensioning until all designed tensioning conditions are completed, and the deviation between the measured internal force of each member and the theoretical design internal force does not exceed 20%, and the overall force balance requirement is met.

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