Testing device and method for unsupported installation of cable-supported grid structure

Abstract

The invention relates to the technical field of building steel structures, in particular to a test device and method for unsupported installation of a cable-supported grid structure, and the device comprises an outer end fixing structure, an inner end fixing structure, a structural radial cable, an annular cable equivalent replacement cable, a pull-down adjusting cable, a lifting rope, an upper steel structure and a supporting rod. According to the test device and method for supporting-free construction of the cable-supported grid structure, a complex space stress structure is simplified into a plane structure through reasonable equivalent substitution according to the stress characteristics of the cable-supported grid, a large-diameter ring cable is replaced with a ring cable equivalent substitution cable arranged in a plane, the structure of the test device is greatly simplified, and the test efficiency is improved. The requirement of a full-scale test on a site is reduced, the test cost is greatly reduced, and the test is convenient to implement.

Description

Technical Field

[0001] The present invention relates to the technical field of building steel structures, and particularly relates to a test device and method for the un-supported installation of a cable-supported lattice structure. Background Art

[0002] The cable-supported lattice structure is a new type of prestressed structure system, which is widely used in public buildings such as stadiums at home and abroad. When installing the cable-supported lattice structure, the "un-supported construction" method can be adopted, that is, without setting up a support frame. By first installing the circumferential cables and radial cables and performing tensioning, setting the lower pull cables to adjust the configuration of the cable net, and then installing the upper lattice structure. This construction method cleverly utilizes the composition of the structure system and the role of the cable system for construction, but has high requirements for construction accuracy. Especially, it is difficult to accurately connect the hoisting unit of the lattice structure with the cable structure. For cable-supported lattice structures with different detailed structures, physical tests are required to simulate and verify the operation process of "un-supported construction" to ensure the smooth progress of project construction.

[0003] For cable-supported lattice structures, there are problems that the similarity in scale tests is difficult to fully meet and the test errors are relatively large. If full-scale tests are carried out according to the design scheme, there are problems such as large scale of test pieces, especially difficult operation due to excessive circumferential cable forces, high requirements for test sites, long test cycles, and high test costs, resulting in great difficulty in test operation.

[0004] Therefore, in view of the above problems, a test device and method for the un-supported installation of a cable-supported lattice structure can be designed. Summary of the Invention

[0005] In order to overcome the problems that in the existing cable-supported lattice structures, the similarity is difficult to fully meet in scale tests, the test errors are relatively large, and the operation difficulty is great.

[0006] The technical solution of the present invention is: a test device for the un-supported installation of a cable-supported lattice structure, including an outer-end fixing structure, and also including an inner-end fixing structure, a structural radial cable, a circumferential cable equivalent substitution cable, a lower pull adjustment cable, a suspension rope, an upper steel structure, and a strut. The right end of the outer-end fixing structure is connected to the structural radial cable, the right end of the structural radial cable is connected to the circumferential cable equivalent substitution cable, the right end of the circumferential cable equivalent substitution cable is connected to the inner-end fixing structure, the lower end of the circumferential cable equivalent substitution cable is connected to the lower pull adjustment cable, one end of the structural radial cable close to the outer-end fixing structure is connected to the upper steel structure, a strut is connected between the upper steel structure and the structural radial cable, and a suspension rope is arranged at the upper end of the upper steel structure.

[0007] Preferably, the outer-end fixing structure is a simulated original structure pressure ring for fixing the structural radial cable, and it needs to have a large horizontal stiffness to ensure that no obvious horizontal deformation occurs during the test process.

[0008] Preferably, the inner-end fixing structure is used to fix the loop cable equivalent substitution cable and should have a large horizontal stiffness to ensure no obvious horizontal deformation during the test.

[0009] Preferably, the structural radial cable is used to simulate the lower radial cable of the original structure, and its specific layout and specifications are the same as those of the original structure.

[0010] Preferably, one end of the loop cable equivalent substitution cable is connected to the structural radial cable and the downward pull adjustment cable, and the other end is connected to the inner-end fixing structure. The loop cable equivalent substitution cable is horizontally arranged within the structural plane, equivalently simulating two horizontal loop cables with an included angle in the original structure.

[0011] Preferably, the axial stiffness EA of the loop cable equivalent substitution cable equivalently simulating the original structure should be equal to the horizontal stiffness component of the loop cable in the original designed structure within the vertical plane of the radial cable and the ground.

[0012] Preferably, the upper end of the downward pull adjustment cable is connected to the structural radial cable and the loop cable equivalent substitution cable, and the lower end of the downward pull adjustment cable is fixed to the ground. The downward pull adjustment cable is a control cable added during the test, and there is no such adjustment cable in the original structure. A cable adjustment device needs to be set at a position near the ground for easy operation for the downward pull adjustment cable, and the cable force and cable length can be adjusted during the test to adjust the elevation of the cable intersection point.

[0013] Preferably, the upper steel structure and the strut are used to simulate the corresponding members of the original structure, and their specific layout and specifications are the same as those of the original structure. After the upper steel structure and the strut are connected, they are lifted as a whole.

[0014] Preferably, the upper steel structure is provided with lifting ropes according to the construction plan to simulate the on-site construction process during the test. By gradually adjusting and lowering the lifting ropes, the gradual lowering and attitude adjustment of the upper steel structure are realized.

[0015] Preferably, this test is mainly used to simulate and check whether the connection between the upper steel structure and the structural radial cable is smooth during the un-supported construction process of the cable-supported lattice structure, and whether its construction accuracy meets the requirements.

[0016] A test method for the un-supported installation of a cable-supported lattice structure, which includes the test device for the un-supported installation of a cable-supported lattice structure as described above, and the steps are as follows:

[0017] S1. Connect the structural radial cable and the loop cable equivalent substitution cable, and fix the two ends to the outer-end fixing structure and the inner-end fixing structure respectively;

[0018] S2. Tension the structural radial cable through the tensioning equipment so that the cable force of the structural radial cable reaches the target cable force;

[0019] S3. Connect the drop - down adjustment cable to the inner end of the structural radial cable, control the cable force and cable length of the drop - down adjustment cable so that the lower cable structure reaches the designed configuration, and then fix the drop - down adjustment cable to the ground;

[0020] S4. Connect the upper steel structure and the struts, and hang the lifting ropes on the upper steel structure;

[0021] S5. Lift and install the upper steel structure, and rotate the angle of the upper steel structure by adjusting the length of the lifting ropes, making the upper steel structure slightly inclined, and connect the upper steel structure to the outer - end fixed structure;

[0022] S6. Gradually adjust and lower the lifting ropes so that the upper steel structure first contacts the outer - end fixed structure and connect and fix this node;

[0023] S7. Then gradually adjust and lower the lifting ropes. While the upper steel structure rotates around the outer fixed point, synchronously adjust the drop - down cables according to the measurement results to adjust the configuration of the lower cable structure, so that one strut under the upper steel structure gradually contacts the structural radial cable and connect and fix this node;

[0024] S8. Repeat the above process until all nodes of the structural radial cable and the struts are connected and fixed;

[0025] S9. Temporarily fix the upper steel structure to ensure its stability; remove the lifting ropes to complete the unsupported installation simulation test of the segmented unit;

[0026] S10. According to the measurement results of the deformation, stress, etc. of the structure during the simulation experiment, combined with the theoretical simulation analysis, compare and evaluate the feasibility, reliability, etc. of the experiment.

[0027] Advantages of the present invention:

[0028] (1) Simplify the structure of the test device: According to the mechanical characteristics of the cable - supported grid, the present invention uses a ring cable to equivalently replace the large - loop - circumferential cable of the cable - supported grid by setting an equivalent replacement cable, and simplifies the overall space structure with a planar structure for test simulation, greatly simplifying the structure of the test device and reducing the requirements for the test site;

[0029] (2) Reduce the test cost: The planar - structure test device of the present invention greatly reduces the number of test components and devices, and also significantly reduces the test cost;

[0030] (3) The test is easier to operate: The test device of the present invention only needs to operate on a single - bay planar structure, which can greatly reduce the operation difficulty of this test;

[0031] (4) Low test risk: The cable force angle of the equivalent substitution cable of the circumferential cable is more direct than that of the original circumferential cable. Only about 10% of the cable force of the original circumferential cable is required, which can greatly reduce the diameter of this cable and significantly reduce the demand for the reaction device, thus reducing the test risk;

[0032] (5) High test credibility: Full-scale tests can better improve the credibility of the tests and can more accurately guide the construction of actual projects. Description of the Drawings

[0033] Figure 1 It is a three-dimensional structure schematic diagram and a force diagram of a typical cable-supported lattice structure

[0034] Figure 2 It is a schematic diagram of the equivalent substitution of the circumferential cable;

[0035] Figure 3 It is a schematic diagram for converting the axial stiffness of the equivalent substitution cable of the circumferential cable;

[0036] Figure 4 It is a simplified diagram and a force diagram of the full-scale test device for the construction technology of the cable-supported lattice structure without supports;

[0037] Figure 5-1 It is a step diagram for completing the tensioning of the radial cables, equivalent substitution cables of the circumferential cables and the drop cables of the structure;

[0038] Figure 5-2 It is a step diagram for hoisting the upper steel structure, gradually lowering it into place, and connecting it to the outer fixed end and the radial cables of the structure;

[0039] Figure 5-3 It is a step diagram for the upper steel structure to be lowered into place and connected to the cables, installing the temporary stabilizing rods, and removing the lifting ropes;

[0040] Figure 5-4 It is a step diagram for relaxing and removing the drop cables to complete the full-scale test.

[0041] Description of the reference numerals: 1. Outer fixed structure; 2. Inner fixed structure; 3. Radial cables of the structure; 4. Equivalent substitution cables of the circumferential cables; 5. Drop adjustment cables; 6. Lifting ropes; 7. Upper steel structure; 8. Struts. Detailed Implementation Manner

[0042] The present invention will be further described below in conjunction with the drawings and embodiments.

[0043] Please refer to Figure 1 - Figure 5-4 , the present invention provides an embodiment:

[0044] A typical cable-supported lattice structure mainly consists of an outer compression ring, an inner ring structure, inner ring cables, radial cables of the structure, struts, and an upper steel structure. Figure 1It is a typical unit structure of a cable-supported grid structure. A spatial structure system is formed by arranging a circle of typical units circumferentially. Among them, the inner ring nodes mainly bear the radial force of the radial cables of the structure, the horizontal inner ring cable forces on both sides, and the axial force of the struts downward.

[0045] It can be seen from Figure 2 that the present invention mainly aims at Figure 1 the typical unit. By using the circumferential cable equivalent substitution cable to substitute two horizontal circumferential cables with an included angle in the original structure, the force effects before and after are made consistent, so as to simplify the spatial structure force system into a planar structure system.

[0046] The circumferential cable equivalent substitution cable is more directly stressed. Assuming that the axial force of the circumferential cable is F and the horizontal included angle between the circumferential cable and the radial cable is α, it can be known by force decomposition that the force of the circumferential cable equivalent substitution cable is 2F*cosα. Therefore, the axial stiffness EA 环索等效代换索 = EA 环索 *2cosα, that is, the axial stiffness EA should be equal to the horizontal stiffness component of the circumferential cable of the original designed structure in the plane perpendicular to the ground of the radial cable. Therefore, the cable diameter can be greatly reduced. For details, see Figure 3 .

[0047] Please refer to Figure 4 - Figure 5-4 . In this embodiment, a test device for the cable-supported grid structure without support construction includes an outer-end fixed structure 1, and also includes an inner-end fixed structure 2, a structural radial cable 3, a circumferential cable equivalent substitution cable 4, a downward pull adjustment cable 5, a suspension rope 6, an upper steel structure 7, and a strut 8. The right end of the outer-end fixed structure 1 is connected to the structural radial cable 3. The right end of the structural radial cable 3 is connected to the circumferential cable equivalent substitution cable 4. The right end of the circumferential cable equivalent substitution cable 4 is connected to the inner-end fixed structure 2. The lower end of the circumferential cable equivalent substitution cable 4 is connected to the downward pull adjustment cable 5. One end of the structural radial cable 3 close to the outer-end fixed structure 1 is connected to the upper steel structure 7. A strut 8 is connected between the upper steel structure 7 and the structural radial cable 3. A suspension rope 6 is arranged at the upper end of the upper steel structure 7.

[0048] The outer end fixing structure 1 is a pressure ring simulating the original structure, used to fix the structural radial cable 3; the inner end fixing structure 2 is used to fix the ring cable equivalent substitution cable 4; the structural radial cable 3 is used to simulate the lower radial cable of the original structure; the ring cable equivalent substitution cable 4 is horizontally arranged within the structural plane, equivalently simulating two horizontal ring cables with an included angle in the original structure; the axial stiffness EA of the ring cable equivalent substitution cable 4 should be equal to the horizontal stiffness component of the original design structure's ring cable within the vertical plane of the radial cable and the ground; the upper end of the downward pull adjusting cable 5 is connected to the structural radial cable 3 and the ring cable equivalent substitution cable 4, and the lower end is fixed to the ground, and a cable adjusting device is arranged at a position near the ground for easy operation, which can adjust the cable force and cable length during the test, and is used to adjust the elevation of the cable intersection point; the upper steel structure 7 is provided with a lifting rope 6 according to the construction plan to simulate the on-site construction process during the test. By gradually adjusting and lowering the lifting rope 6, the gradual lowering and attitude adjustment of the upper steel structure 7 are realized; after the upper steel structure 7 is connected to the strut 8, it is lifted as a whole, used to simulate and test whether the connection between the upper steel structure 7 and the structural radial cable 3 is smooth during the construction process of the cable-supported lattice structure without support, and whether its construction accuracy meets the requirements.

[0049] A test method for the unsupported installation of a cable-supported lattice structure, which includes the test device for the unsupported installation of a cable-supported lattice structure as described above, and the steps are as follows:

[0050] S1. Connect the structural radial cable 3 and the ring cable equivalent substitution cable 4, and fix the two ends to the outer end fixing structure 1 and the inner end fixing structure 2 respectively;

[0051] S2. Tension the structural radial cable 3 through a tensioning device so that the cable force of the structural radial cable 3 reaches the target cable force;

[0052] S3. Connect the downward pull adjusting cable 5 to the inner end of the structural radial cable 3, control the cable force and cable length of the downward pull adjusting cable 5 so that the lower cable structure reaches the designed configuration, and then fix the downward pull adjusting cable 5 to the ground;

[0053] S4. Connect the upper steel structure 7 and the strut 8, and fix the lifting rope 6 on the upper steel structure 7;

[0054] S5. Lift the upper steel structure 7, and rotate the angle of the upper steel structure 7 by adjusting the length of the lifting rope 6 so that the upper steel structure 7 is slightly inclined, and connect the upper steel structure 7 to the outer end fixing structure 1;

[0055] S6. Gradually adjust and lower the lifting rope 6 so that the upper steel structure 7 first contacts the outer end fixing structure 1 and fixes the connection of this node;

[0056] S7. Gradually adjust and lower the suspension rope 6 again. While the upper steel structure 7 rotates around the outer fixed point, synchronously adjust the lower stay cable 5 according to the measurement results to adjust the configuration of the lower cable structure, so that one strut 8 under the upper steel structure 7 gradually contacts the structural radial cable 3, and connect and fix this node;

[0057] S8. Repeat the above process until all nodes of the structural radial cable 3 and the strut 8 are connected and fixed;

[0058] S9. Temporarily fix the upper steel structure 7 to ensure its stability; remove the suspension rope 6 to complete the unsupported installation simulation test of the segmented unit;

[0059] S10. According to the measurement results such as the deformation and stress of the structure during the simulation experiment, combined with the theoretical simulation analysis, compare and evaluate the feasibility, reliability, etc. of the experiment.

[0060] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the purpose of the present invention, such as changing the number of struts, refining the specific form of the upper steel structure, expanding or reducing the scale of the test section of the upper steel structure, adjusting the attitude and material of the lower stay cable or the equivalent substitution cable of the ring cable, etc.

Claims

1. A test device for the unsupported installation of a cable-supported grid structure, comprising an outer end fixing structure (1), characterized in that: The invention also comprises an inner end fixed structure (2), a structural radial cable (3), a ring cable equivalent replacement cable (4), a pull-down adjustment cable (5), a suspension rope (6), an upper steel structure (7), and a strut (8). The right end of the outer end fixed structure (1) is connected to the structural radial cable (3), the right end of the structural radial cable (3) is connected to the ring cable equivalent replacement cable (4), the right end of the ring cable equivalent replacement cable (4) is connected to the inner end fixed structure (2), the lower end of the ring cable equivalent replacement cable (4) is connected to the pull-down adjustment cable (5), one end of the structural radial cable (3) close to the outer end fixed structure (1) is connected to the upper steel structure (7), a strut (8) is connected between the upper steel structure (7) and the structural radial cable (3), and a suspension rope (6) is arranged at the upper end of the upper steel structure (7).

2. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 1, characterized in that: The outer end fixing structure (1) simulates the pressure ring of the original structure and is used to fix the radial cable (3) of the structure, and needs to have a large horizontal rigidity.

3. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 1, characterized in that: The inner end fixing structure (2) is used to fix the ring rope equivalent replacement rope (4) and needs to have a large horizontal rigidity.

4. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 2, characterized in that: The structural radial cables (3) are used to simulate the lower radial cables of the original structure.

5. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 3, characterized in that: One end of the hoop cable equivalent replacement cable (4) is connected to the structural radial cable (3) and the pull-down adjustment cable (5), and the other end is connected to the inner end fixed structure (2). The hoop cable equivalent replacement cable (4) is horizontally arranged in the structural plane, and is equivalent to simulating two horizontal hoop cables with an angle in the original structure.

6. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 5, characterized in that: The axial stiffness EA of the equivalent replacement cable (4) in the original structure should be equal to the horizontal stiffness component of the original design structure's hoop cable in the radial plane perpendicular to the earth.

7. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 5, characterized in that: The upper end of the pull-down adjustment rope (5) is connected to the structural radial rope (3) and the ring rope equivalent replacement rope (4), and the lower end of the pull-down adjustment rope (5) is fixed to the ground. The pull-down adjustment rope (5) is a control rope added during the test. The pull-down adjustment rope (5) needs to be provided with a rope adjustment device at a position near the ground for easy operation.

8. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 1, characterized in that: The upper steel structure (7) is provided with a suspension rope (6) according to the construction plan to simulate the on-site construction process during the test, and the upper steel structure (7) is gradually lowered and its posture adjusted by gradually adjusting and lowering the suspension rope (6).

9. A test device and method for the unsupported installation of a cable-supported grid structure according to claim 8, characterized in that: The test is mainly used to simulate and test whether the upper steel structure (7) is gradually connected to the structural radial cables (3) smoothly during the unsupported construction of the cable-supported grid structure, and whether the construction accuracy meets the requirements.

10. A test method for the unsupported installation of a cable-supported grid structure, characterized in that: A test device for the unsupported installation of a cable-supported grid structure according to any one of claims 1 to 9, comprising the following steps: S1. Connect the structural radial cable (3) and the ring cable equivalent replacement cable (4), and connect and fix the two ends to the outer end fixed structure (1) and the inner end fixed structure (2); S2. tensioning the radial cable (3) of the structure by tensioning equipment so that the cable force of the radial cable (3) of the structure reaches the target cable force; S3. Connect the pull-down adjustment cable (5) to the inner end of the structural radial cable (3), control the cable force and cable length of the pull-down adjustment cable (5) so that the lower cable structure reaches the designed position, and then fix the pull-down adjustment cable (5) to the ground; S4. The upper steel structure (7) and the support rod (8) are connected, and the suspension rope (6) is fixed to the upper steel structure (7); S5. Hoist the upper steel structure (7), and rotate the angle of the upper steel structure (7) by adjusting the length of the lifting rope (6) so that the upper steel structure (7) is slightly tilted, and connect the upper steel structure (7) to the outer end fixed structure (1); S6. Gradually adjust and lower the suspension rope (6) so that the upper steel structure (7) first contacts the outer end fixed structure (1) to connect and fix the node; S7. Then gradually adjust and lower the suspension rope (6) so that the upper steel structure (7) rotates around the outer fixed point, and at the same time, adjust the lower cable (5) according to the measurement results to adjust the shape of the lower cable structure, so that a support rod (8) under the upper steel structure (7) gradually contacts the radial cable (3) of the structure, and connects and fixes the node; S8. Repeat the above process until all nodes of the structure radial cable (3) and the strut (8) are connected and fixed; S9. Temporarily fix the upper steel structure (7) to ensure its stability; The suspension rope (6) is removed to complete the unsupported installation simulation test of the block unit; S10. Based on the measurement results of structural deformation, stress, etc. during the simulation experiment, combined with theoretical simulation analysis, the feasibility and reliability of the experiment are compared and evaluated.

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