CN114411951A

CN114411951A - Local chord is supported and is made up spatial grid structure

Info

Publication number: CN114411951A
Application number: CN202210209333.XA
Authority: CN
Inventors: 刘宜丰; 谢俊乔; 夏循; 马永兴; 周劲炜
Original assignee: China Southwest Architectural Design and Research Institute Co Ltd
Current assignee: China Southwest Architectural Design and Research Institute Co Ltd
Priority date: 2022-03-03
Filing date: 2022-03-03
Publication date: 2022-04-29
Anticipated expiration: 2042-03-03
Also published as: CN114411951B

Abstract

The invention discloses a local chord support combined grid structure, which comprises a grid and a plane truss, wherein the grid is connected with the grid through a cable; the grid at the midspan part of the net rack is replaced by a plane truss, the upper chord of the plane truss is connected with the upper chord of the net racks at the two sides, and the lower chord of the plane truss is connected with the lower chord of the net racks at the two sides; the lower chord adopts a stretchable chord. The local chord support combined grid structure provided by the invention has the advantages of strong roof modeling adaptability, less indoor space occupation, smaller thrust on the supporting column and the like.

Description

Local chord is supported and is made up spatial grid structure

Technical Field

The invention relates to the technical field of constructional engineering, in particular to a local chord support combined grid structure.

Background

The spatial grid structure is a new structure developed vigorously in the middle of the 20 th century, and is a structural form formed by arranging a plurality of rods according to a certain rule in space and connecting the rods through nodes. The spherical house cover of Shanghai academy of teachers and schools built in 1964 is a net rack structure, and is characterized by light dead weight, strong spanning capability, standardized rod piece nodes, easy installation and the like due to the space stress characteristic, so that the spherical house cover is widely applied to the fields of stadiums, movie theaters, traffic buildings, industrial workshops, warehouses and the like.

Along with the development of building industry and aesthetic improvement of buildings in recent years, more and more roof structures with free roof modeling and huge fluctuation appear, wherein arch roofs can cause larger horizontal thrust to roof supporting columns, column bottom bending moment caused by the horizontal thrust often causes the supporting columns to be difficult to design, and span can be reduced only by increasing the supporting columns or a self-balancing string-stretching integral structure, such as a string-stretching truss and a string-stretching beam, can be adopted by adjusting a structural scheme. Although the thrust on the supporting column can be reduced through self-balancing in the tension string integral structure, the through vertical cables occupy more space indoors, and the applicable scene is limited.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the invention provides a local chord support combined grid structure for solving the problems, and the grid structure has the advantages of strong roof modeling adaptability, less indoor space occupation, smaller thrust to the supporting column and the like.

The invention is realized by the following technical scheme:

a local chord branch combined grid structure comprises a grid and a plane truss; the grid at the midspan part of the net rack is replaced by a plane truss, the upper chord of the plane truss is connected with the upper chord of the net racks at the two sides, and the lower chord of the plane truss is connected with the lower chord of the net racks at the two sides; the lower chord adopts a stretchable chord.

Along with the development of building industry and aesthetic improvement of buildings in recent years, more and more roof structures with free roof modeling and huge fluctuation appear, wherein arch roofs can cause larger horizontal thrust to roof supporting columns, column bottom bending moment caused by the horizontal thrust often causes the supporting columns to be difficult to design, and span can be reduced only by increasing the supporting columns or a self-balancing string-stretching integral structure, such as a string-stretching truss and a string-stretching beam, can be adopted by adjusting a structural scheme. Although the thrust on the supporting column can be reduced through self-balancing in the tension string integral structure, the through vertical cables occupy more space indoors, and the applicable scene is limited. Based on the technical background, the invention provides a novel structural form of hybridization of a common grid structure and a string structure, local grids at the mid-span part of the grid are converted into a plane truss structure, the lower chord of the plane truss adopts a tension rod, and the new grid structure after hybridization has the advantages of strong roof modeling adaptability, less indoor space occupation, smaller thrust to a supporting column and the like.

The local chord support combined grid structure provided by the invention fully utilizes the mechanical characteristic that the middle and lower parts of the structure span are only pulled, combines the excellent pulling performance and the characteristic of pre-tensioning of the lower chord, partially balances the thrust of the arched roof by tensioning the lower chord in the construction process, reduces the horizontal thrust borne by the supporting column, is beneficial to the design of the supporting column on the premise of not additionally occupying the indoor space, and ensures that the whole structure is established. The mid-span area of the net rack is arranged by adopting a plane truss, so that the lower chord members are arranged along the span direction in a one-way manner, and construction tensioning is facilitated.

Preferably, the lower chord is a steel pull rod or a steel cable, and is arranged by adopting a double pull rod or a pull cable.

More preferably, the non-midspan part of the net rack is an orthogonal rectangular pyramid net rack.

Further preferably, the lower chord is hinged with the lower chord of the net racks on the two sides.

Preferably, the lower chord is hinged with the lower chord of the net rack through a connecting node II; and the connecting node II comprises a pin shaft ear plate II, and the lower chord and the pin shaft ear plate II are assembled and connected through a pin shaft II perforation and transmit axial tension along the lower chord.

Preferably, the connection node II further comprises a hollow spherical crown and an ear plate connection circular tube; the axial both ends that the pipe is connected to the otic placode all set gradually round pin axle otic placode II and hollow spherical crown from inside to outside, and the rack lower chord of both sides rack is connected pipe and hollow spherical crown with the otic placode and is connected, and the rack web member of both sides rack is connected with hollow spherical crown.

Further preferably, hollow spherical crown, round pin axle otic placode II and otic placode connection pipe welded connection in proper order, rack lower chord member and otic placode connection pipe and hollow spherical crown welded connection, rack web member and hollow spherical crown welded connection.

Further preferably, the system further comprises a connecting node I; the plane truss comprises an upper chord, a stay bar and a lower chord; the upper chord and the two support rods form an inverted isosceles triangle structure, and the lower ends of the support rods are connected with the lower chord through a connecting node I and transmit vertical component force caused by stretching the lower chord; one end of the lower chord is hinged with the connecting node I, and the other end of the lower chord is hinged with the lower chord of the net rack. The lower chords on the two sides of the connecting node I are arranged in a V shape, so that the lower chords have certain verticality, and the upper chords are arched through the support rods during tensioning.

Preferably, the connecting node I comprises a pin shaft lug plate I, a support rod connecting plate and a pin shaft I; the two pin shaft ear plates I are connected through a stay bar connecting plate; holes are formed in two ends of each pin shaft ear plate I, and the lower chord and the pin shaft ear plates I are assembled and connected through pin shaft I through perforation and transmit axial tension along the pull rod.

Preferably, the connection node I further comprises a coordination stiffening plate, and the coordination stiffening plate is arranged between the two pin shaft ear plates I; the coordination stiffening plates play a role in coordinating the deformation of the pin shaft ear plates I on the two sides and enabling the connection nodes I to be integrally stressed.

The invention has the following advantages and beneficial effects:

the invention provides a novel structural form of hybridization of a common grid structure and a string structure, and has the advantages of strong roof modeling adaptability, less indoor space occupation, smaller thrust on a supporting column and the like.

The local chord combination grid structure provided by the invention adopts a hybridization grid form, the non-mid-span area adopts an orthogonal square pyramid grid, and the mid-span area is converted into a plane truss; the lower chord member of the partial mid-span of the local chord-supported combined grid structure adopts a steel pull rod (or a steel cable) capable of being tensioned, pretensioning is carried out in the construction process, the thrust of the arched roof is partially balanced, the horizontal thrust borne by the supporting column is reduced, the design of the supporting column is facilitated on the premise of not additionally occupying the indoor space, and the whole structure is formed.

Because the steel pull rod or the stay cable has the risk of loosening or breaking, based on the design concept of preventing continuous collapse and the consideration of structural redundancy, the double pull rods or the stay cables are arranged, the structural safety is not influenced when one of the double pull rods or the stay cable is broken or loosened, the double pull rods or the stay cable has the replacement and maintenance conditions, and the corresponding connecting node is designed on the basis.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

fig. 1 is a schematic axial view of a partial chord support combined grid structure of the invention.

Fig. 2 is a schematic cross-sectional view of the assembled grid structure with partial chords according to the present invention.

FIG. 3 is a schematic structural diagram of a connection node I according to the present invention; wherein, fig. 3(a) shows a schematic perspective structure; fig. 3(b) shows an explosion diagram.

FIG. 4 is a schematic structural diagram of a connection node II according to the present invention; wherein, fig. 4(a) shows a schematic perspective structure; fig. 4(b) shows an explosion diagram.

Fig. 5 is a load-only working condition diagram of the local chord branch combined grid structure of the invention.

FIG. 6 is a force diagram of the local chord member combined grid structure under a pretensioning condition; fig. 6(a) is a cross-sectional view, and fig. 6(b) is a plan view of the mid-span lower chord.

Fig. 7 is a diagram illustrating the actual working condition of the partial chord support combined grid structure of the invention.

Reference numbers and corresponding part names in the drawings:

1-orthogonal square pyramid net rack, 1 a-net rack lower chord, 1 b-net rack web member;

2-plane truss, 2 a-lower chord, 2 b-brace rod, 2 c-upper chord;

3-a support column;

4-connecting node I, 4 a-pin shaft ear plate I, 4 b-brace connecting plate, 4 c-coordinating stiffening plate and 4 d-pin shaft I;

5-connecting node II, 5 a-pin shaft ear plates II, 5 b-hollow spherical crown, 5 c-ear plate connecting circular tube and 5 d-pin shaft II.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that: it is not necessary to employ these specific details to practice the present invention. In other instances, well-known structures, circuits, materials, or methods have not been described in detail so as not to obscure the present invention.

Throughout the specification, reference to "one embodiment," "an embodiment," "one example," or "an example" means: the particular features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment of the invention. Thus, the appearances of the phrases "one embodiment," "an embodiment," "one example" or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combination and/or sub-combination in one or more embodiments or examples. Further, those of ordinary skill in the art will appreciate that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the description of the present invention, the terms "front", "rear", "left", "right", "upper", "lower", "vertical", "horizontal", "upper", "lower", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore, should not be construed as limiting the scope of the present invention.

Example 1

The embodiment provides a local chord member combined grid structure, which comprises a grid and a plane truss 2; the grid of the mid-span part of the net rack is replaced by a plane truss 2, and the non-mid-span part of the net rack adopts an orthogonal and orthogonal quadrangular pyramid net rack 1. The upper chord 2c of the plane truss 2 is connected with the net rack upper chord of the net racks on both sides, and the lower chord 2a of the plane truss 2 is connected with the net rack lower chord 1a of the net racks on both sides; the lower chord 2a is a stretchable chord, and the lower chord 2a is a steel pull rod or a steel cable. Be different from current string structure arrangement mode, this embodiment will stretch string structure "plane truss 2" and replace rack partial structure itself, realize embedded equipment, obtain the novel spatial grid structure of a hybridization, both can realize reducing the effect of the horizontal thrust that the support post bore, can not additionally encroach on the indoor space simultaneously, roofing molding strong adaptability.

Example 2

The improvement is further improved on the basis of the embodiment 1, the lower chord 2a adopts a double-rod arrangement, and the lower chord 2a is hinged with the net rack lower chord 1a through a connecting node II 5; the connecting node II5 comprises two pin shaft ear plates II5a, two hollow spherical crowns 5b and an ear plate connecting circular tube 5 c.

The axial both ends that the pipe 5c was connected to the otic placode all set gradually round pin axle otic placode II5a and hollow spherical crown 5b from inside to outside, according to hollow spherical crown 5b promptly, round pin axle otic placode II5a, the pipe 5c is connected to the otic placode, the order welded connection as an organic whole structure in proper order of round pin axle otic placode II5a and hollow spherical crown 5b, two round pin axle otic placodes II5a use the otic placode to connect pipe 5c and arrange as basic point symmetrical arrangement, two hollow spherical crowns 5b use the otic placode to connect pipe 5c and arrange as basic point symmetrical arrangement. Two lower chords 2a and two pin shaft ear plates II5a are assembled and connected through pin shafts II5d and are perforated, and the axial tension along the lower chords 2a is transmitted.

The net rack lower chord 1a of the net racks on the two sides is connected with the ear plate connecting circular tube 5c and the hollow spherical crown 5b, and the net rack web members 1b of the net racks on the two sides are connected with the hollow spherical crown 5 b. The lower chord 1a of the net rack is connected with the ear plate by a circular tube 5c and a hollow spherical crown 5b in a welding way, and the web member 1b of the net rack is connected with the hollow spherical crown 5b in a welding way.

Example 3

The improvement is further improved on the basis of the embodiment 2, and the system also comprises a connecting node I4; the plane truss 2 comprises an upper chord 2c, two support rods 2b and four lower chords 2 a; the two axial ends of the upper chord 2c are respectively connected with the end parts of the two support rods 2b, the lower ends of the two support rods 2b are connected to a connecting node I4, and the upper chord 2c and the support rods 2b form an inverted isosceles triangle structure; one end of the lower chord 2a is hinged with the connecting node I4, and the other end is hinged with the pin shaft ear plate II5a of the connecting node II 5.

The connecting node I4 comprises a pin lug plate I4a, a brace connecting plate 4b, a coordinating stiffening plate 4c and a pin I4 d. The two pin shaft lug plates I4a are connected through a stay bar connecting plate 4b, and the two pin shaft lug plates I4a have the same structure and are symmetrically arranged with the plate surfaces parallel to each other; holes are formed in two axial ends of each pin shaft ear plate I4a, and the lower chord 2a and the pin shaft ear plate I4a are assembled and connected through the pin shaft I4d through holes, and the axial tension of the pull rod is transmitted. The upper end surface of the stay bar connecting plate 4b is connected with the free end of the stay bar 2b in a welding way. Two lower chords 2a at one axial end of the connecting node I4 (which is axially coaxial with the pin shaft lug plate I4 a) are a group of open chords, two lower chords 2a at the other axial end of the connecting node I4 (which is axially coaxial with the pin shaft lug plate I4 a) are a group of open chords, and the two groups of open chords are arranged in a vertical V shape.

The two coordination stiffening plates 4 are arranged between the two pin shaft ear plates I4 a; the coordinating stiffening plates 4 play a role in coordinating the deformation of the pin shaft ear plates I4a on the two sides and causing the whole connection node I4 to be stressed. The pin shaft lug plate I4a is connected with the stay bar connecting plate 4b, the shaft lug plate I4a is connected with the coordination stiffening plate 4 through welding.

Fig. 5-7 are force analysis diagrams of the support column of the partial chord member combined grid structure in the using process.

Fig. 5 shows the structural stress condition of the local truss-supported combined grid structure in a loaded state, and the arched roof forms an external thrust P and a vertical pressure F on the supporting column 3, and the graph also reflects the stress state of the conventional grid structure.

Fig. 6(a) and 6(b) show the stress condition of the local chord support combined grid structure under the pretensioning condition of the steel pull rods, in the construction process, the steel pull rods of the plane truss 2 are applied with the active pretension of P1, and the continuous lower chords with V-shaped planes are arranged in the grid transformation area, so that the lower chords of the square pyramid grid structure are transformed into the vertical plane where the upper chord is located to form the plane truss, and the axial internal force of the lower chords of the truss is effectively transmitted. The tension is balanced by the V-shaped lower chord of the grid transformation area, the force is transmitted to the supporting columns 3 on two sides through the lower chord 1a of the net rack, and the tension of P2 is formed on the supporting columns 3 after the structural balance and the internal force redistribution.

Fig. 7 shows the stress condition of the local chord-supported combined grid structure during actual operation, which is the superposition of the load state and the pretensioning working condition, and the actual thrust of the roof on the supporting column 3 is P ', P' < P. It should be noted that, because the structure has slight nonlinearity, P' ≠ P-P2, the analysis of the local chord combination grid structure should take into account the geometric nonlinearity, and the calculation should calculate the structural effect under each working condition combination, so it is not suitable to adopt the calculation method of the combination effect after the calculation of the single working condition.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A local chord support combined grid structure comprises a grid, and is characterized by also comprising a plane truss (2); the grid at the midspan part of the net rack is replaced by a plane truss (2), an upper chord (2c) of the plane truss (2) is connected with the upper chords of the net racks at two sides, and a lower chord (2a) of the plane truss (2) is connected with the lower chords (1a) of the net racks at two sides; the lower chord (2a) adopts a stretchable chord.

2. A partial corbel composite grid structure according to claim 1, wherein the lower chords (2a) are steel ties or cables and are arranged in double ties or cables.

3. A partial chord composite spatial grid structure according to claim 1, characterized in that the non-midspan part of the grid is an orthogonal rectangular pyramid grid (1).

4. A partial corbel composite grid structure according to any of claims 1 to 3, wherein the lower chord (2a) is hingedly connected to the lower chords (1a) of the grids on either side.

5. A partial chord composite grid structure according to claim 4, characterized in that the lower chord (2a) is hinged with the lower chord (1a) of the grid through a connecting node II (5); the connecting node II (5) comprises a pin shaft ear plate II (5a), and the lower chord (2a) and the pin shaft ear plate II (5a) are assembled and connected through a pin shaft II (5d) perforation and transmit axial tension along the lower chord (2 a).

6. A partial corbel composite grid structure according to claim 5, wherein the connecting nodes II (5) further comprise a hollow spherical cap (5b) and a lug plate connecting circular tube (5 c);

the axial both ends that pipe (5c) are connected to the otic placode all set gradually round pin axle otic placode II (5a) and hollow spherical crown (5b) from inside to outside, and pipe (5c) and hollow spherical crown (5b) are connected with the otic placode to the rack lower chord member (1a) of both sides rack, and the rack web member (1b) and the hollow spherical crown (5b) of both sides rack are connected.

7. The local chord combination grid structure according to claim 5, wherein the hollow spherical crown (5b), the pin shaft ear plate II (5a) and the ear plate connecting circular tube (5c) are welded in sequence, the grid lower chord (1a) and the ear plate connecting circular tube (5c) and the hollow spherical crown (5b) are welded, and the grid web member (1b) and the hollow spherical crown (5b) are welded.

8. A partial corbel composite grid structure according to any of claims 1 to 3, further comprising a connecting node I (4); the plane truss (2) comprises an upper chord (2c), a stay bar (2b) and a lower chord (2 a); the upper chord and the two support rods (2b) form an inverted isosceles triangle structure, the lower ends of the support rods (2b) are connected with the lower chord (2a) through a connecting node I (4) and transmit vertical component force caused by stretching the lower chord (2 a); one end of the lower chord (2a) is hinged with the connecting node I (4), and the other end of the lower chord is hinged with the lower chord (1a) of the net rack.

9. The partial corbel composite grid structure according to claim 8, wherein the connecting node I (4) comprises a pin lug I (4a), a brace connecting plate (4b) and a pin I (4 d);

the two pin shaft ear plates I (4a) are connected through a stay bar connecting plate (4 b); holes are formed in two ends of each pin shaft ear plate I (4a), and the lower chord (2a) and the pin shaft ear plates I (4a) are assembled and connected through pin shaft I (4d) through perforation and transmit axial tension along the pull rod.

10. The local truss combined grid structure of claim 9, wherein the connecting node I (4) further comprises a coordinating stiffening plate (4c), and the coordinating stiffening plate (4) is arranged between two pin shaft ear plates I (4 a); the coordinating stiffening plate (4) plays a role in coordinating the deformation of the pin shaft ear plates I (4a) at the two sides and enabling the connecting node I (4) to be integrally stressed.