A control method for vertical deformation and support reaction of a large-span steel structure roof with multiple towers

Abstract

A method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof, which relates to the field of building construction. The method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof includes the following steps: selecting the truss of the multi-tower long-span steel structure roof; setting the roof supports according to the layout of the lower support structure of the multi-tower long-span steel structure roof; selecting the form of the roof supports; selecting the stiffness of the roof supports; controlling the vertical deformation of the roof; and controlling the strength of the roof members. The method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof provided by this application can ensure that the vertical deformation of the long-span part of the roof is controlled within an ideal range, so as to achieve both the effect of reducing the peak and filling the valley of the horizontal reaction force of the roof supports and making the horizontal reaction force of the roof supports tend to be balanced, and can ensure that the vertical deformation of the roof meets the design requirements, and reduce the tensile degree of the concrete at the roof supports and the design difficulty of the supporting concrete structure.

Description

Technical Field

[0001] The present application relates to the field of building construction, and more particularly, to a method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof. Background Art

[0002] With the rapid development of China's economic construction, the construction of large public buildings such as high-speed railway stations, stadiums, exhibition halls, and airport terminals has also achieved great development. In these major, especially landmark projects, long-span or even ultra-long-span spatial steel structures can be seen everywhere.

[0003] There are problems of deformation coordination at the long-span peripheral supports of the ultra-long-span steel structure roof and it is sensitive to temperature loads. In structural design, sliding supports are usually used to release the deformation coordination internal force and temperature internal force. The vertical deformation and support reaction force at the long-span part are directly related to the stiffness of the roof support. Using sliding supports will make it difficult for the vertical deformation of the long-span and large overhanging parts of the roof to meet the design requirements. Although using fixed supports can ideally control the vertical deformation of the long-span and large overhanging parts of the roof, it will also cause huge and uneven horizontal reaction forces at the supports, resulting in excessive local stress on the structure, which is extremely unfavorable to the overall stress of the structure. Summary of the Invention

[0004] The purpose of the present application is to provide a method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof, which can ensure that the vertical deformation of the long-span part of the roof is controlled within an ideal range, so as to achieve both the effect of reducing the peak and filling the valley of the horizontal reaction force of the roof support and making the horizontal reaction force of the roof support tend to be balanced, and can ensure that the vertical deformation of the roof meets the design requirements, and reduce the tensile degree of the concrete at the roof support and the design difficulty of the supporting concrete structure.

[0005] The embodiments of the present application are implemented as follows:

[0006] The method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof provided by the present application includes the following steps:

[0007] Select the truss of the multi-tower long-span steel structure roof; select the truss according to the design standards by comprehensively considering the truss layout and load-bearing conditions of the multi-tower long-span steel structure roof;

[0008] Optimize the layout of the roof supports and roof components of the multi-tower long-span steel structure roof; set the roof supports according to the layout of the lower supporting structure of the multi-tower long-span steel structure roof, calculate and analyze the multi-tower long-span steel structure roof according to the single-body model, and adjust the height of the truss, the layout of the truss members, and the cross-sectional size of the truss members according to the deformation conditions of the long-span part of the roof to control the deformation of the long-span part of the roof within a reasonable preset range;

[0009] Select the form of the roof support; analyze using the overall model of the multi-tower long-span steel structure roof, and adjust the parameters of the roof support according to the analysis results of the force on the roof support and the vertical deformation of the roof;

[0010] Select the stiffness of the roof support; set variable stiffness supports as the roof supports, and set different initial stiffnesses for the roof supports according to different stress parts. When the horizontal reaction force of the roof support is greater than the bearing capacity corresponding to its initial stiffness, the roof support undergoes horizontal displacement, and the stiffness of the roof support increases linearly with the amount of water level displacement. Transfer and disperse the horizontal force exceeding the bearing capacity of the roof support to other roof supports through the components connected to the roof support;

[0011] Control the vertical deformation of the roof; adjust and calculate the initial stiffness of each roof support one by one to minimize the horizontal reaction force and vertical deformation of the roof support within the preset range to maintain dynamic balance. Repeat this step until the initial stiffness adjustment of all roof supports is completed to obtain the overall calculation model;

[0012] Control the strength of the roof components; calculate using the overall model of the multi-tower long-span steel structure roof with variable stiffness supports set to obtain the range of cross-section stress ratios of the upper chord, lower chord, web members of the roof truss, and the members connected to the roof support.

[0013] AIn some alternative embodiments, the variable stiffness support is a spherical hinge support.

[0014] In some alternative embodiments, the initial stiffness of the roof support is above 2 kN / mm.

[0015] In some alternative embodiments, adjust and calculate the initial stiffness of each roof support one by one to make the horizontal reaction force of the roof support below 800 kN.

[0016] The beneficial effects of the present application are as follows: The method for controlling the vertical deformation and support reaction force of a multi-tower long-span steel structure roof provided by the present application includes the following steps: Select the truss of the multi-tower long-span steel structure roof; Select the truss according to the design standards by comprehensively considering the truss layout and load-bearing conditions of the multi-tower long-span steel structure roof; Optimize the layout of the roof supports and roof components of the multi-tower long-span steel structure roof; Set the roof supports according to the layout of the lower support structure of the multi-tower long-span steel structure roof, calculate and analyze the multi-tower long-span steel structure roof according to the single-body model, and adjust the height, layout of truss members, and cross-sectional size of truss members according to the deformation of the long-span part of the roof to control the deformation of the long-span part of the roof within a reasonable preset range; Select the form of the roof support; Analyze using the overall model of the multi-tower long-span steel structure roof, and adjust the parameters of the roof support according to the analysis results of the force on the roof support and the vertical deformation of the roof; Select the stiffness of the roof support; Set a variable-stiffness support as the roof support, and set different initial stiffnesses for the roof support according to different stress parts. When the horizontal reaction force of the roof support is greater than the bearing capacity corresponding to its initial stiffness, the roof support undergoes a horizontal displacement, and the stiffness of the roof support increases linearly with the horizontal displacement amount, and transfer and disperse the horizontal force exceeding the bearing capacity of the roof support to other roof supports through the components connected to the roof support; Control the vertical deformation of the roof; Adjust and calculate the initial stiffness of each roof support one by one to minimize the horizontal reaction force and vertical deformation of the roof support within the preset range to maintain dynamic balance, and repeat this step until the initial stiffness adjustment of all roof supports is completed to obtain the overall calculation model; Control the strength of the roof components; Calculate using the overall model of the multi-tower long-span steel structure roof with variable-stiffness supports set to obtain the cross-sectional stress ratio range of the upper chord, lower chord, web members of the roof truss, and the members connected to the roof support. The method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof provided by the present application can ensure that the vertical deformation of the long-span part of the roof is controlled within an ideal range, so as to achieve the effect of reducing the peak and filling the valley of the horizontal reaction force of the roof support, making the horizontal reaction force of the roof support tend to be balanced, ensuring that the vertical deformation of the roof meets the design requirements, and reducing the tensile degree of the concrete at the roof support and the design difficulty of the supporting concrete structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0018] Figure 1Axonometric view of the overall structure model of the multi-tower long-span steel structure roof treated with the method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof provided by the embodiments of the present application;

[0019] Figure 2 Distribution schematic diagram of the roof supports and truss structures of the multi-tower long-span steel structure roof treated with the method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof provided by the embodiments of the present application.

[0020] Reference numerals in the drawings: 100, roof support; 110, two-way orthogonal truss; 120, special-shaped open-web truss. Detailed implementation manners

[0021] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Usually, the components of the embodiments of the present application described and illustrated herein can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0023] It should be noted that: similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0024] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed when in use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0025] In addition, terms such as "horizontal", "vertical", "overhanging", etc. do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0026] In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "arranged", "installed", "connected", and "joined" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0027] In the present application, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or only means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or only means that the horizontal height of the first feature is lower than that of the second feature.

[0028] The features and performance of the method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof in the present application will be further described in detail below in conjunction with the embodiments.

[0029] As Figure 1 and Figure 2 shown, the method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof in the embodiment of the present application is used to process a certain multi-tower long-span steel structure roof, which is a large-span steel structure roof shared by three towers, with a total length of 350 meters, a maximum span of 117 meters, and a maximum overhanging length of 41 meters. Only vertical and horizontal forces are transmitted between it and the lower supporting concrete structure, and no moment is transmitted. The control method includes the following steps:

[0030] Select the type of the multi-tower long-span steel structure roof; select the type according to the design standards by comprehensively considering the layout and load-bearing conditions of the multi-tower long-span steel structure roof. After comparative analysis, a two-way orthogonal truss 110 structure is adopted inside each tower of the multi-tower long-span steel structure roof, and a special-shaped open-web truss 120 structure is adopted outside the range of each tower;

[0031] Arrangement of roof supports 100 and optimization of roof member arrangement for large-span steel structure roof of multi-tower; setting roof supports 100 according to the arrangement of the lower supporting structure of concrete for the large-span steel structure roof of multi-tower, calculating and analyzing the multi-tower large-span steel structure roof by single-body model, and adjusting the height of the truss, the arrangement position of truss members and the cross-sectional size of truss members according to the deformation of the large-span part of the roof, so as to control the deformation of the large-span part of the roof within a reasonable preset range;

[0032] Selection of the form of roof supports 100; analyzing by using the overall model of the large-span steel structure roof of multi-tower, and adjusting the parameters of roof supports 100 according to the analysis results of the force on roof supports 100 and the vertical deformation of the roof;

[0033] Selection of the stiffness of roof supports 100; setting variable-stiffness supports as roof supports 100, where the variable-stiffness support is a spherical hinge support that can move horizontally when the horizontal reaction force acting on it is greater than the bearing capacity corresponding to its initial stiffness. The initial stiffness of roof supports 100 is set to 2 kN / mm, 12 kN / mm and 20 kN / mm according to different stress parts. When the horizontal reaction force of roof supports 100 is greater than the bearing capacity corresponding to its initial stiffness, the roof supports 100 will have a horizontal displacement, and the stiffness of roof supports 100 will increase linearly with the horizontal displacement. The horizontal force exceeding the bearing capacity of roof supports 100 is transmitted and diffused to other roof supports 100 through the components connected to roof supports 100;

[0034] Control of roof vertical deformation; adjusting and calculating the initial stiffness of roof supports 100 one by one; during the calculation, on the one hand, the horizontal reaction force of roof supports 100 should be controlled within a reasonable range, so that the horizontal reaction force of roof supports 100 is below 800 kN, and on the other hand, the vertical deformation of the roof should be controlled within a reasonable range and minimized as much as possible, so that the horizontal reaction force and vertical deformation of roof supports 100 are minimized within the preset range to maintain dynamic balance. Repeat this step until the initial stiffness adjustment of all roof supports 100 is completed to obtain the overall calculation model. According to the calculation results, the maximum vertical displacement at the mid-span of the large span is finally controlled at 431 mm, and the maximum vertical displacement at the large cantilever end is finally controlled at 328 mm, which ideally meets the vertical deformation design requirements of the specification

[0035] Component strength control of the roof; the overall calculation model of the multi-tower and extra-long large-span steel structure roof with variable stiffness bearings is used for calculation, and it is obtained that the section stress ratio of the upper chord of the roof truss, the section stress ratio of the lower chord of the roof truss are not greater than 0.8, the section stress ratio of the web members of the roof truss is not greater than 0.85, and the section stress ratio of the members connected to the roof bearing 100 is not greater than 0.70. The roof members are all box-shaped steel pipes, and the material is Q355B. The columns of the frame structure of the lower support structure at the bottom of the roof bearing 100 are rectangular concrete columns with the material of C45, and the frame beams of the lower support structure are rectangular concrete beams with the material of C35.

[0036] The method for controlling the vertical deformation and bearing reaction of the multi-tower large-span steel structure roof provided by the embodiment of the present application is to first select the truss structure for the multi-tower large-span steel structure roof, and then determine the layout of the roof bearing 100 and the optimization of the layout of the roof components of the multi-tower large-span steel structure roof. According to the deformation of the large-span part of the roof, the height of the truss, the layout position of the truss members and the section size of the truss members are adjusted to control the deformation of the large-span part of the roof within a reasonable preset range. Then, the roof is connected to the lower support structure through a spherical hinge bearing with variable stiffness. The initial stiffness of the roof bearing 100 is determined according to the force condition of its location. When the horizontal reaction force of the roof bearing 100 is greater than the bearing capacity corresponding to the initial stiffness of the roof bearing 100, the roof bearing 100 can slide horizontally. The stiffness of the roof bearing 100 and the horizontal sliding displacement are in a linear relationship, so as to release the horizontal reaction force of the roof bearing 100 through the horizontal displacement of the roof bearing 100. However, because the roof bearing 100 has an initial stiffness and the stiffness changes with the horizontal displacement after the horizontal displacement occurs, it is ensured that the vertical deformation of the large-span part of the roof will not be significantly different from that when using fixed bearings and is controlled within an ideal range. Thus, it can achieve both the effect of peak shaving and valley filling for the horizontal reaction force of the roof bearing 100 to make the horizontal reaction force of the roof bearing 100 tend to be balanced, and can also ensure that the vertical deformation of the roof ideally meets the design requirements, greatly reducing the tensile degree of the concrete at the roof bearing 100 and reducing the design difficulty of the supporting concrete structure. There is a new breakthrough in the method for controlling the vertical deformation and horizontal bearing reaction of the multi-tower extra-long large-span steel structure roof, providing a new design method for industry technicians.

[0037] The above-described embodiments are some embodiments of the present application, rather than all embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the scope of protection of the present application.

Claims

1. A method for controlling the vertical deformation and support reaction force of a large-span steel structure roof with multiple towers, characterized in that, It includes the following steps: Select the truss of the multi-tower long-span steel structure roof; select it by comprehensively considering the truss layout and load-bearing conditions of the multi-tower long-span steel structure roof according to the design standards; Optimize the roof supports and the layout of roof components of the multi-tower long-span steel structure roof; set the roof supports according to the layout of the lower support structure of the multi-tower long-span steel structure roof, calculate and analyze the multi-tower long-span steel structure roof according to the single-body model, and adjust the height of the truss, the layout of truss members and the cross-sectional size of truss members according to the deformation of the long-span part of the roof to control the deformation of the long-span part of the roof within a reasonable preset range; Select the form of the roof support; analyze using the overall model of the multi-tower long-span steel structure roof, and adjust the parameters of the roof support according to the analysis results of the force on the roof support and the vertical deformation of the roof; Select the stiffness of the roof support; set a variable stiffness support as the roof support, and the roof support is provided with different initial stiffness according to different stress parts. When the horizontal reaction force of the roof support is greater than the bearing capacity corresponding to its initial stiffness, the roof support is caused to have a horizontal displacement, and the stiffness of the roof support increases linearly with the amount of water level displacement, and the horizontal force exceeding the bearing capacity of the roof support is transmitted and diffused to other roof supports through the components connected to the roof support; Control the vertical deformation of the roof; adjust and calculate the initial stiffness of each roof support one by one to minimize the horizontal reaction force and vertical deformation of the roof support within the preset range to maintain dynamic balance, and repeat this step until the initial stiffness adjustment of all roof supports is completed to obtain an overall calculation model; Control the strength of the roof components; calculate using the overall model of the multi-tower long-span steel structure roof provided with variable stiffness supports to obtain the range of cross-sectional stress ratios of the upper chord, lower chord, web members of the roof truss and the members connected to the roof support; 2. The method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof described in claim 1, wherein The variable stiffness support is a spherical hinge support.

3. The method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof described in claim 1, wherein The initial stiffness of the roof support is above 2 kN / mm.

4. The method for controlling the vertical deformation and support reaction force of the multi-tower long-span steel structure roof cover according to claim 1, characterized in that Adjust and calculate the initial stiffness of each roof support one by one to make the horizontal reaction force of the roof support below 800 kN.

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