Large-span arched steel structure system with multiple arches and self-balanced load

Abstract

The present invention provides a multi-arch joint force-bearing self-balancing large-span arched steel structure system, comprising a central arch and a large-span curved roof steel structure frame arranged on both sides of the central arch, and the large-span curved roof steel structure frames at the two wings, which realize the large span in the two-dimensional direction of the plane under the arch of the structure. Except for the supporting side columns at one end, the space under the roof no longer needs columns for support, thereby improving the freedom of planning and layout in the building space adopting the structure. In theory, as long as the height of the main arch frame is high enough, the large-span curved roof steel structure frames on the two wings of the structure can have a sufficiently high clearance height to meet the clearance height requirements of different large-span buildings.

Description

Technical Field

[0001] The invention relates to a large-span arched steel structure, in particular to a large-span arched steel structure system with multiple arches jointly bearing force and being self-balanced. Background Art

[0002] Large-span buildings generally refer to buildings with roof spaces spanning more than 30m. In some buildings, due to functional requirements, large spaces must be used and columns are not allowed in the middle, such as gymnasiums, theaters, exhibition halls, conference halls, airport waiting halls, train waiting halls, ship waiting halls and other public buildings, as well as industrial buildings such as factories, hangars and other large warehouses. These buildings all require large-span building structure support.

[0003] At present, most of the existing large-span buildings are constructed with large-span space-effect structures, which can not only meet the requirements of building appearance and space, but also make the structural layout and force transmission efficiency consistent with the building appearance, and achieve a high degree of integration between the building and the structure. Among them, the large-span arched steel structure, as a common large-span space-effect structure, has been effectively used in both the bridge industry and the construction industry.

[0004] The arch structure is also called thrust structure. Its characteristic is that it decomposes the pressure into downward pressure and outward thrust. It is the only structure that produces outward thrust among all structures. Under the action of vertical load, the horizontal thrust generated by the arch foot can reduce the bending moment of the arch body and convert the bending moment generated by the vertical load into axial pressure. In this way, the strength of the material can be fully utilized. Therefore, the spanning capacity of the arch steel structure is better than other structures, which can save a lot of steel and cement.

[0005] However, the long-span arched structure is different from straight members such as beams (bending members) and columns (compression-bending members). Its in-plane and out-of-plane calculated lengths are difficult to determine, and its instability mechanism and design method are quite different from those of straight members such as beams and columns. The in-plane and out-of-plane stability is the focus and difficulty of arched structure design. This also leads to the limitations of long-span arched steel structure buildings: that is, the existing long-span arched steel structure can often only achieve a large span without columns in a single dimensional direction under the arch, and cannot achieve a large span without columns in two dimensional directions under the arch. This is because when constructing ancillary buildings in the out-of-plane direction of the arch, in order to support the roof of the arched structure and the roof of the ancillary buildings, enough columns need to be set up to meet the requirements of overall structural stability.

[0006] Taking the steel truss structure of the roof of Shenyang South Railway Station Central Station as an example, the east-west span can reach 286.5 meters, but the north-south span can only be within 66 meters without columns, and the auxiliary roofs on the south and north sides can only achieve a span of 21 meters.

[0007] Taking the station building and canopy steel structure of Harbin West Railway Station as an example, the east-west span of the station building can reach nearly 300 meters without any columns, but the south and north platform canopies require a large number of columns for support.

[0008] In summary, the existing research on large-span arch steel structures mainly focuses on the research and application of the in-plane and out-of-plane stability of a single arch. There is little research and application on the reasonable arrangement of structural components to make the arch steel structure form a structural system that can be self-balanced both in the plane and out of the plane. Summary of the invention

[0009] The purpose of the present invention is to provide a multi-arch joint force-bearing self-balancing large-span arch steel structure system, aiming to achieve a large-span column-free structure in two dimensional directions of the arch under the plane of a large-span building.

[0010] In order to achieve the above object, the present invention adopts the following technical solution:

[0011] A multi-arch joint force-bearing self-balancing large-span arch steel structure system comprises an arch frame consisting of at least one upper chord arch of a steel structure, at least one lower chord truss and at least two pile caps, wherein the pile caps are used to support two arch feet of the upper chord arch, and is characterized in that the arch steel structure system consists of a central arch and a large-span curved roof steel structure frame arranged on both sides of the central arch; wherein,

[0012] The central arch comprises two main arch frames formed by a pair of mutually symmetrical, long-span arch frames inclined toward each other outside the plane, two secondary arches arranged between the two upper chord arches of the two main arch frames and connecting the arch feet of the two upper chord arches, at least three top trusses for connecting and positioning the distance between the upper chord arches of the two main arch frames, at least one top arch frame which is perpendicular to and intersects the top trusses, is connected to the secondary arches at both ends, and has the same or similar curvature as the main arch frames, wherein the lower chord truss of the main arch frame is arranged in the plane of the main arch frame and is located at the waist of the upper chord arch of the main arch frame, which is called a waist truss; the top trusses have at least two for connecting to the waist trusses of the two main arch frames and the connecting nodes of the upper chord arches respectively;

[0013] The large-span curved roof steel structure frame is composed of a large-span curved longitudinal top frame and a straight transverse top frame that are crisscrossed to form a curved grid roof projected as a rectangle. One short side end of the rectangle is connected to the waist truss, and the other short side end extends outward from the center arch plane. At least three supporting side columns are arranged at the other end of the large-span curved roof steel structure frame.

[0014] The two large-span main arch frames tilted toward each other out of the plane in the central arch described in the present invention means that each main arch frame tilts toward the other main arch frame out of the plane at a certain angle.

[0015] The working principle of the present invention is:

[0016] By utilizing the large-span main arch frame that is inclined at a certain angle out of the plane toward the other main arch frame, and by arranging a secondary arch frame, a top truss and a top arch frame between the two main arch frames, the two main arch frames support each other, forming a stable structural system, which greatly improves the out-of-plane stability of the main arch frame; the setting of the waist truss reduces the calculated length of the main arch frame in the plane, and greatly enhances the in-plane stability of the main arch frame; the large-span curved roof steel structure frame is connected at the waist truss of the central arch, which effectively bears the lateral and vertical loads transmitted by the large-span curved roof steel structure frame, and combined with the supporting side columns at the other end of the large-span curved roof steel structure frame, while achieving the maximum span of the dimension out of the plane of the central arch without columns, it ensures the self-balance of the entire structure under the condition of combined force, thereby forming a multi-arch combined force self-balanced structural system with extremely high stability. While achieving a large span in two dimensions of the plane under the arch of the structure, in addition to setting supporting side columns at one end, the space under the roof no longer needs columns for support, which increases the freedom of planning and layout in the building space using this structure. In theory, as long as the height of the main arch frame is high enough, the large-span curved roof steel structure frames on both wings of the structure will have a high enough clearance height to meet the clearance height requirements of different large-span buildings.

[0017] The upper chord arch of the main arch frame described in the present invention can adopt a geometrically symmetrical arch structure, such as an elliptical arc, a circular arc, a parabola, a catenary arch, etc.; it can also adopt a geometrically asymmetric steel arch structure. Studies have shown that the geometric asymmetry of the arch body has a better effect on the stability of the steel arch structure.

[0018] It is recommended that the upper chord arch and waist truss in the main arch frame of the central arch described in the present invention both adopt box-type truss structures.

[0019] The waist truss at the waist of the main arch frame bears a large reaction force due to the vertical load of the large-span curved roof steel structure frame, resulting in excessive deflection of the waist truss, which is not conducive to the structural stability of the main arch frame. Therefore, the present invention can also be improved as follows:

[0020] At least three pairs of slings are arranged between the upper chord arch and the waist truss in the plane of the main arch frame, the top ends of the slings are connected to the upper chord arch of the main arch frame, and the bottom ends are connected to the waist truss, and the distances between each sling are equal.

[0021] By setting up slings under the main arch frame to bear the vertical load of the curved roof frame, the internal force deformation effect of the waist truss is significantly improved. The in-plane stiffness of the main arch frame is effectively utilized to improve the vertical stiffness of the waist truss, reduce its calculated span, and provide space for optimizing the cross-section of the horizontal waist truss. At the same time, the slings also improve the stability of the main arch frame under the half-span load. On the premise of meeting safety requirements, the steel consumption of the waist truss can be reduced, thereby saving economic costs.

[0022] In order to increase the span of the large-span curved roof steel structure frame on both sides of the central arch so that the large-span curved roof steel structure frame has a larger slope, the present invention can further be improved as follows:

[0023] The multi-arch joint force-bearing self-balancing large-span arched steel structure system also includes a horizontal arch penetrating and overlapping the large-span curved roof steel structure frame at the connection between the large-span curved roof steel structure frame and the waist truss, and the two ends of the horizontal arch are respectively connected to the two ends of the waist truss. The arch rise is preferably in the range of 0.2 to 0.45.

[0024] By arranging a horizontal arch near the connection between the large-span curved roof steel structure frame and the waist truss, the lateral stiffness can be effectively increased, and the large out-of-plane reaction force and deformation of the main arch frame caused by the vertical permanent live load generated by the connection between the curved roof steel structure frame and the central arch due to the large span and large slope of the curved roof steel structure frame can be offset, and the horizontal thrust of the large roof on the outside of the plane of the central arch under the action of wind and temperature is weakened, so that the horizontal displacement value of the structure is reduced by about 30% under the same lateral load. It can not only solve the problem of greatly increasing the cross-section of the rods of the main arch frame due to the above-mentioned force conditions, resulting in a significant increase in the amount of steel and reduced economic benefits; at the same time, it can also greatly reduce the axial force of other rods except the horizontal arch, so that the central arch does not need to increase the rods to ensure stability, which can further reduce the amount of steel used and become more economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A three-dimensional diagram of a multi-arch joint force-bearing self-balancing large-span arched steel structure system according to Embodiment 1 of the present invention;

[0026] Figure 2 Schematic diagram of the support conditions of the arch foot of the central arch according to the first embodiment of the present invention;

[0027] Figure 3 This is a first-order elastic buckling deformation modal diagram of the central arch described in Example 1 of the present invention;

[0028] Figure 4 This is a second-order elastic buckling deformation modal diagram of the central arch described in Example 1 of the present invention;

[0029] Figure 5 This is a modal diagram of the third-order elastic buckling deformation of the central arch described in Example 1 of the present invention;

[0030] Figure 6 A top view of a large-span arched steel structure system with multiple arches jointly bearing force and self-balancing according to the second embodiment of the present invention;

[0031] Figure 7The wind load F of the large-span arched steel structure system with multiple arches and self-balanced joint force according to the second embodiment of the present invention is simulated. h Force diagram when ;

[0032] Figure 8 In the third embodiment of the present invention, F h Schematic diagram of the lateral type variation at the mid-span of the end of the curved roof under the action of the

[0033] Fig. 9 In the third embodiment of the present invention, F h Schematic diagram of the axial force of each member in the mid-span of the end of the curved roof under the action;

[0034] Fig.10 In the second embodiment of the present invention, F h Schematic diagram of the lateral type variation at the mid-span of the end of the curved roof under the action of the

[0035] Fig.11 In the second embodiment of the present invention, F h Schematic diagram of the axial force of each member in the mid-span of the end of the curved roof under the action;

[0036] Fig.12 is the lateral displacement D at the mid-span of the end of the curved roof in the second embodiment of the present invention x (mm) relative to the interface area A (m 2 ) Relationship curve diagram;

[0037] Fig.13 It is a deformation diagram of the multi-arch joint force self-balanced large-span arch steel structure system under the action of vertical load when no suspension cables are provided;

[0038] Fig.14 It is a deformation diagram of the multi-arch joint force self-balanced large-span arch steel structure system under the action of vertical load when the sling is set;

[0039] Fig.15 This is the deformation diagram of the main arch frame under the action of half-span vertical load without slings;

[0040] Fig.16 This is the deformation diagram of the main arch frame under the action of half-span vertical load with suspenders;

[0041] Among them: 1 central arch; 11 upper chord arch in the main arch frame; 12 secondary arch; 13 top truss; 14 top arch frame; 15 waist truss; 2 curved roof; 3 supporting side columns; 4 suspension cables; 5 horizontal arch. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0043] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom, inside, outside, vertical, horizontal, longitudinal, counterclockwise, clockwise, circumferential, radial, axial...), then the directional indication is only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0044] The present invention proposes a multi-arch combined force self-balancing large-span arch steel structure system (hereinafter referred to as the structure), which includes a central arch 1 and a large-span curved roof 2 steel structure frame (hereinafter referred to as the curved roof 2) arranged on both sides of the central arch 1. In the following embodiments, the buckling performance of the multi-arch combined force self-balancing large-span arch steel structure system is analyzed using Midas Gen software.

[0045] In the first to third embodiments of the present invention, the buildings adopt the structure, and the horizontal projection size is 253m×63.55m=16079m 2 That is, the north-south span is 63.55m, the east-west span is 253m, and the highest point of the building is 27.55m. It is a large-span steel structure. The main vertical load-bearing components include two main arch frames 11 located at the building entrance of the central arch 1 and seven supporting side columns 3 located at the ends of the roof coverings on both sides.

[0046] In the first embodiment of the present invention, Figure 1 As shown, the central arch 1 includes a pair of symmetrical long-span main arch frames 11 inclined in opposite out-of-plane directions, a secondary arch 12 arranged between the two main arch frames 11 and connecting the arch feet of the two main arch frames 11, fifteen top trusses 13 close to the rise of the main arch frames 11 and used to connect the two main arch frames 11, three top arch frames 14 perpendicular to the top trusses 13 and used to connect the rise of the secondary arches 12 and corresponding to the arc of the main arch frames 11, and a waist truss 15 arranged in the plane of the main arch frame 11 and located at the waist of the main arch frame 11; one end of the steel structure frame of the long-span curved roof 2 is connected to the waist truss 15, and the other end extends out of the plane of the main arch frame 11, and the other end of the steel structure frame of the long-span curved roof 2 is supported by the ground through at least two supporting side columns 3.

[0047] Specifically, the waist truss is a tie rod waist truss 15. The buckling modal analysis of the central arch 1 is performed. The support conditions of the arch foot are as follows: Figure 2 As shown in the figure, after being analyzed by Midas Gen software, its first-order elastic buckling deformation mode is as follows Figure 3 As shown in Figure 2, it can be seen that the first-order elastic buckling is an out-of-plane buckling load factor of 1119, which is 1.07 times the corresponding double main arch buckling load factor. The second-order elastic buckling deformation mode is as follows: Figure 4 As shown in the figure, the second-order elastic buckling is out-of-plane instability, and the buckling load factor is 1456, which is 1.19 times the buckling load factor of the corresponding double main arch frame. The third-order elastic buckling deformation mode is as follows Figure 5 As shown, it can be seen that the third-order elastic buckling is instability in the plane, and the buckling load factor is 1654, which is 1.16 times the buckling load factor of the corresponding double main arch frame. It can be seen that the arrangement of the secondary arch 12 and the tie rod waist truss 15 improves the in-plane and out-of-plane stability of the double main arch frame 11, and the degree of improvement in the in-plane stability is greater than the degree of improvement in the out-of-plane stability.

[0048] In the second embodiment of the present invention, based on the first embodiment, as Figure 6 As shown, it also includes a horizontal arch 5 close to the connection between the steel structure frame of the large-span curved roof 2 and the waist truss 15 and penetrating the steel structure frame of the large-span curved roof 2. The head and tail ends of the horizontal arch 5 are respectively connected to the head and tail ends of the waist truss 15. Eleven pairs of slings 4 are arranged between the main arch frame 11 and the waist truss 15. The top end of the sling 4 is connected to the main arch frame 11, and the bottom end is connected to the waist truss 15. The distance between each sling 4 is equal.

[0049] When the central arch 1 of the present invention is not provided with the horizontal arch 5, the large-span arch steel structure system with multiple arches jointly bearing force and self-balancing is as follows Figure 1 As shown in FIG. 1 , it is to intuitively reflect the relationship between the lateral stiffness of the multi-arch joint force self-balanced large-span arch steel structure system and the horizontal arch 5 and waist truss 15 components, as shown in FIG. Figure 7 As shown, a row of F is applied to the end of the curved roof frame 2 on the side wing. h = 1000kN simulated strong wind node load, verify the structural internal force and displacement under its action, after analysis by Midas Gen software, the lateral deformation D of the mid-span connection end of the curved roof frame 2 and the tie rod waist truss 15 without the horizontal arch 5 is x (mm) Figure 8 As shown, in F h (kN) The axial force of the mid-span members at the ends of the two wings is as follows: Fig. 9 The lateral displacement D of the connection end of the curved roof 2 frame with horizontal arch 5 and the tie rod waist truss 15 at the mid-span is shown as follows. x (mm) Fig.10 As shown, in F h (kN) under the action of the axial force of the mid-span members at the ends of the two wings Fig.11It can be seen that under the structural arrangement of horizontal arch 5, the mid-span lateral displacement of the horizontal connecting truss of the main arch frame is 42.7mm, parallel to the direction of the main arch frame 11, the axial force of the secondary beam of the curved roof 2 frame is relatively uniform, the axial force is about 450kN, and the axial force of the horizontal arch 5 bar reaches 1300kN, indicating that it effectively participates in resisting the lateral load.

[0050] Specifically, the axial cross-sectional area of ​​the horizontal arch 5 is 0.0205m 2 -0.1583m 2 The axial cross-sectional areas of the horizontal arch 5 are P450x15 (A = 0.0205m 2 )、P500x30(A=0.044m 2 )、P800x30(A=0.0726m 2 )、P1000x30(A=0.0914m 2 )、P1300x40(A=0.1583m 2 )、P1500x40(A=0.1835m 2 ) After analysis by Midas Gen software, the mid-span lateral displacement D is calculated based on the calculation results. x (mm) relative to the interface area A (m 2 ) Relationship curve diagram Fig.12 As shown in the figure, it can be seen that below the P500x30 section, the lateral displacement of the structure decreases rapidly with the increase of the arch structure stiffness, while above the P1000x30 section, as the horizontal arch 5 structure stiffness increases, the mid-span lateral displacement D x (mm) decreases gradually, when A=0.1583m 2 When the mid-span lateral displacement D x (mm)Min.

[0051] In the third embodiment of the present invention, based on the first embodiment, eleven slings 4 are arranged between the main arch frame 11 and the waist truss 15, the top end of the sling 4 is connected to the main arch frame 11, and the bottom end is connected to the waist truss 15, and the distance between each sling 4 is equal.

[0052] Specifically, 13 sets of 2P245x12 steel pipes are used for the sling 4. q = 1.35xDL + 1.4x0.7xLL is used as the representative value of the vertical load for research. After analysis by Midas Gen software, the deformation shape of the structure under the vertical load when the sling 4 is not set is as follows: Fig.13 As shown, when the sling 4 is set, the deformation shape of the structure under the vertical load is as follows Fig.14 It can be seen that, in the case of setting the suspension cable 4, the rigidity of the tie rod waist truss 15 is improved, the supporting effect on the two-wing curved roof 2 is more obvious, and the force boundary conditions of the two-wing curved roof 2 can be better improved.

[0053] In addition, the cable is an important member connecting the main arch frame and the tie rod waist truss 15. In addition to improving the stiffness of the tie rod waist truss 15, it also significantly improves the in-plane stability of the main arch frame. The main arch frame 11 is subjected to force verification under the half-span vertical load according to the structure without and with the sling 4. After analysis by the Midas Gen software, the verification results without the sling 4 are as follows: Fig.15 As shown, the calculation results of sling 4 are as follows Fig.16 As shown, it can be seen that under the action of half-span load, the deformation of the main arch frame presents a concave shape in the half-span with load and a convex shape in the half-span without load. When the sling 4 is set, the concave deformation and convex deformation of the main arch frame 11 are reduced by 9% and 29% compared with the case when the sling 4 is set, indicating that in the convex section, the sling 4 is pulled, providing a larger in-plane stiffness for the main arch frame. Therefore, the sling 4 has a significant effect on reducing the vertical displacement of the tie rod waist truss 15 and reducing the internal force of the tie rod waist truss 15. At the same time, the sling 4 also improves the stability of the main arch frame under the action of half-span load.

[0054] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A multi-arch joint force-bearing self-balancing long-span arch steel structure system, comprising at least one upper chord arch of a steel structure, at least one lower chord truss and an arch frame composed of at least two pile caps, wherein: The pile cap is used to support the two arch feet of the upper arch, and is characterized in that the arched steel structure system consists of a central arch and a large-span curved roof steel structure frame arranged on both sides of the central arch; wherein, The central arch comprises two main arch frames formed by a pair of mutually symmetrical, long-span arch frames inclined toward each other outside the plane, two secondary arches arranged between the two upper chord arches of the two main arch frames and connecting the arch feet of the two upper chord arches, at least three top trusses for connecting and positioning the distance between the upper chord arches of the two main arch frames, at least one top arch frame which is perpendicular to and intersects the top trusses, is connected to the secondary arches at both ends, and has the same or similar curvature as the main arch frames, wherein the lower chord truss of the main arch frame is arranged in the plane of the main arch frame and is located at the waist of the upper chord arch of the main arch frame, which is called a waist truss; the top trusses have at least two for connecting to the waist trusses of the two main arch frames and the connecting nodes of the upper chord arches respectively; The large-span curved roof steel structure frame is composed of a large-span curved longitudinal top frame and a straight horizontal top frame crisscrossed to form a curved grid roof projected as a rectangle, one short side end of the rectangle is connected to the waist truss, and the other short side end extends outward from the center arch plane, and at least three supporting side columns are arranged at the other end of the large-span curved roof steel structure frame; The multi-arch joint force-bearing self-balancing large-span arched steel structure system also includes a horizontal arch penetrating and overlapping the large-span curved roof steel structure frame at the connection between the large-span curved roof steel structure frame and the waist truss, and the two ends of the horizontal arch are respectively connected to the two ends of the waist truss.

2. The multi-arch joint force-bearing self-balancing large-span arch steel structure system according to claim 1 is characterized by: The upper chord arch and waist truss in the main arch frame of the central arch both adopt box-type truss structures.

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