A full bolt splicing truss system aluminum alloy net rack structure and its assembling method

Abstract

The application discloses a full-bolt spliced truss system aluminum alloy grid structure and an assembling method thereof; the upper chord and the lower chord of the truss of the grid structure are both double-slot aluminum combined chords formed by two back-to-back groove-shaped aluminum alloy components, and the chords of the trusses in two directions are vertically staggered at the cross nodes; the shared vertical web members extend into the gap between the double-slot aluminum combined chords, and the outer connecting plates, the web plates of the groove-shaped components and the shared vertical web members are connected through the penetrating stainless steel bolts; box-type connectors are arranged between the nodes. The structure form can avoid the problem of strength reduction of the heat affected zone of the aluminum alloy welding, and breaks through the limitation of high cost and small applicable span of the traditional bolt ball node aluminum alloy grid.

Description

Technical Field

[0001] This invention relates to the field of spatial grid structure technology in building engineering, and in particular to a truss-type aluminum alloy grid structure with all bolts spliced ​​and its assembly method. Background Technology

[0002] Space frame structures, as one of the main structural forms for large-span buildings, are widely used in public buildings such as stadiums, convention centers, and airport terminals due to their advantages such as strong spatial force transmission, high spanning capacity, and diverse architectural forms. Space frame structures come in different forms, including truss systems, triangular pyramids, and square pyramids, as shown below. Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown. Space frame members are typically made of round steel tubing, and common node types are welded hollow sphere nodes or bolted sphere nodes, such as... Figure 5 , Figure 6 As shown, the members are interconnected through nodes to form a spatial force-bearing system. This allows the structure to withstand external loads primarily through axial force on the members, fully utilizing the material strength of the members and achieving good overall performance.

[0003] As human exploration of natural science deepens, scientific experimental facilities are becoming increasingly systematic, precise, and large-scale, placing more stringent and demanding requirements on physical parameters such as remanent magnetization and radiation levels in the environments where these facilities are located. The building structures housing these facilities also need to meet the structural load-bearing requirements while maintaining larger spans, employing low-remanent magnetization or low-background materials suitable for experimental needs. In this context, traditional steel space frame structures are no longer sufficient due to the inherent magnetism of steel, failing to meet the building's requirements. Aluminum alloys, with their extremely low magnetism, lightweight yet high strength, corrosion resistance, and lower manufacturing costs compared to other low-remanent magnetization materials like titanium alloys, have become the ideal structural material for scientific research buildings with stringent remanent magnetization requirements. However, the application of aluminum alloys in space frame structures also presents the following challenges: 1. Due to the inherent physicochemical properties of aluminum alloys, the strength reduction of high-strength grades in the weld heat-affected zone needs to be considered. According to GB 50429-2007 "Code for Design of Aluminum Alloy Structures", for 6-series aluminum alloys in T5 or T6 condition, the strength reduction in the weld heat-affected zone reaches 50%. Therefore, if welded connections are used, measures such as increasing the cross-sectional thickness, setting up reinforcement structures, or performing post-weld treatment are required to ensure the load-bearing capacity of the joint, thereby increasing construction costs.

[0004] 2. For aluminum alloy space frame structures with bolted ball joints, stainless steel bolted balls and stainless steel bolts are generally used to reduce the risk of galvanic corrosion, but this increases the structural cost. At the same time, stainless steel bolts have limited load-bearing capacity. Therefore, bolted ball aluminum alloy space frames are generally used in small-span structures.

[0005] The above problems limit the application of aluminum alloy space frame structures.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the general background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a fully bolted truss-type aluminum alloy space frame structure and its assembly method, to solve the problems of material performance degradation caused by welding of aluminum alloy space frames and the increased cost and span limitations caused by using stainless steel bolt balls. The space frame chords adopt double-groove members, and the chords of the two trusses are staggered vertically, so that the chords are continuous in the node area and connected to the vertical and diagonal web members by stainless steel bolts, avoiding welding of aluminum alloy components and realizing full assembly splicing between aluminum alloy members.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: This invention provides a fully bolted truss-type aluminum alloy space frame structure, comprising multiple first planar trusses spaced apart along a first direction and multiple second planar trusses spaced apart along a second direction. Both the first and second planar trusses include upper chords, lower chords, vertical web members, and diagonal web members. The two sets of planar trusses are connected at intersection nodes to form a cross-truss system space frame with spatial load-bearing capacity. Depending on the arrangement of the web members, the planar trusses can adopt Warren or Pratt forms, such as... Figure 7 , Figure 8 , Figure 10 , Figure 11 As shown; the specific tension and compression distribution of the web members should be determined through structural calculations, taking into account the load direction, support conditions, and geometric arrangement.

[0009] In this invention, both the upper and lower chords are double-groove aluminum composite chords. Each double-groove aluminum composite chord consists of two grooved aluminum alloy components arranged back-to-back with their webs facing each other. The vertical and diagonal webs can be rectangular or square aluminum alloy tubes. At intersections, the chords in both directions are staggered vertically to avoid direct intersection. The common vertical web at the intersection extends into the gap between the two grooved aluminum alloy components of the double-groove aluminum lattice structure. The nodes also feature external connecting plates located on the outside of the double-groove aluminum composite chords. Through-bolts pass sequentially through the external connecting plates, the webs of the grooved aluminum alloy components, and the common vertical web, ensuring a reliable connection between the chords and webs at the node. This structure utilizes the gap between the double-groove aluminum composite chords to create a space for web insertion, which helps reduce the number of node components, decrease unilateral connection eccentricity, and improve the force transmission efficiency of the node. In a double-groove aluminum composite chord, box-shaped fittings are spaced apart between the two grooved aluminum alloy members. Stainless steel bolts are used to connect the web of the grooved aluminum alloy members to the box-shaped fittings, improving the stability of the grooved aluminum alloy members. Figure 16 , Figure 17 As shown. This structure allows the aluminum alloy square tube to simultaneously assume a dual role—serving as both a vertical web member of the space frame and a component of the connecting nodes. The nodes are simple in construction and clearly transmit loads, allowing loads in any direction to be effectively transferred through the nodes, forming a spatially loaded structural system. Stainless steel bolts are used as fasteners, such as... Figure 12 , Figure 13 , Figure 14 , Figure 15 As shown. The stainless steel bolt group at the node can be verified for load-bearing capacity and structural integrity based on the structural load, internal forces of the members, thickness of the connecting plate, and bolt arrangement, in accordance with the current relevant standards for aluminum alloy structures, stainless steel fasteners, and spatial grid structures.

[0010] This invention also provides an assembly method for a fully bolted truss-type aluminum alloy space frame structure, comprising the following steps: Drilling, numbering, and pre-assembly of the double-groove aluminum composite chord, vertical web members, diagonal web members, outer connecting plates, and box-type fittings; Insert the common vertical web member between the two slotted aluminum alloy components of the double-slotted aluminum composite chord; The two planar trusses are assembled into a space frame unit according to the staggered relationship of the intersection nodes; Install the outer connecting plate and insert through stainless steel bolts; Install diagonal bracing and box-type fittings; Tighten the through stainless steel bolts in stages according to the design sequence, and connect the space frame unit to the support node.

[0011] By adopting the above technical solution, the present invention has the following beneficial effects: 1. The double-groove aluminum composite chords in two directions are staggered vertically at the intersection nodes, share a common vertical web member inserted into the gap between the double-groove composite chords, and are connected by outer connecting plates and through stainless steel bolts, which can realize the full bolt assembly connection of the truss system aluminum alloy space frame.

[0012] 2. The system uses high-strength stainless steel bolts for connection, which avoids the quality risks such as strength reduction in the heat-affected zone of aluminum alloy welding, porosity and hot cracks caused by welding. No on-site welding work is required, and the installation is convenient and efficient.

[0013] 3. Compared with aluminum alloy space frames using stainless steel bolt ball joints, this system uses channel-shaped aluminum alloy components, rectangular or square web members and connectors to form joints, which helps to reduce the number of special joint parts, reduce joint processing costs, and enable larger structural spans. Attached Figure Description

[0014] To more clearly illustrate the structure and specific embodiments of the present invention, a brief description of the accompanying drawings will be provided below: Figure 1 This is a three-dimensional schematic diagram of a truss-type space frame structure in the prior art.

[0015] Figure 2 This is a plan view of a truss-type space frame structure in the existing technology.

[0016] Figure 3 This is a plan view of a triangular pyramidal space frame structure in the existing technology.

[0017] Figure 4 This is a plan view of a quadrangular pyramidal space frame structure in the prior art.

[0018] Figure 5 This is a schematic diagram of the construction of a welded hollow sphere joint in the prior art.

[0019] Figure 6 This is a schematic diagram of the construction of a bolt ball joint in the prior art.

[0020] Figure 7 A three-dimensional schematic diagram of the all-bolted Warren truss system aluminum alloy space frame structure provided by the present invention.

[0021] Figure 8 Elevation view of the all-bolted Warren truss system aluminum alloy space frame structure provided by the present invention.

[0022] Figure 9 This is a partial schematic diagram of the fully bolted Warren truss system aluminum alloy space frame structure provided by the present invention.

[0023] Figure 10 A three-dimensional schematic diagram of the all-bolted Pratt truss aluminum alloy space frame structure provided by the present invention.

[0024] Figure 11 Elevation view of the all-bolted Pratt truss aluminum alloy space frame structure provided by the present invention.

[0025] Figure 12 A three-dimensional schematic diagram of a universal connection node provided by the present invention.

[0026] Figure 13 Elevation and sectional views of the universal connection node provided by the present invention.

[0027] Figure 14 A three-dimensional schematic diagram of the upper chord web member node of the Warren truss system aluminum alloy space frame provided by the present invention.

[0028] Figure 15 Elevation and sectional views of the upper chord web member nodes of the Warren truss system aluminum alloy space frame provided for this invention.

[0029] Figure 16 A three-dimensional schematic diagram of the node of the chord member of the space frame provided by the present invention.

[0030] Figure 17 Elevation and sectional views of the space frame chord lacing node provided for this invention.

[0031] Figure 18 This is a schematic diagram of the node of the additional connecting member with web bar provided by the present invention.

[0032] Figure 19 This is a schematic diagram of the additional connecting member for the web member provided by the present invention.

[0033] Among them: 1 is the longitudinal planar truss, 2 is the transverse planar truss, 3 is the diagonal web member, 4 is the vertical web member, 5 is the through stainless steel bolt, 6 is the longitudinal lower chord, 7 is the transverse lower chord, 8 is the upper chord, 9 is the double-slot aluminum composite chord, 10 is the outer connecting plate, 11 is the box-type fitting, 12 is the additional connecting piece, and 13 is the large-section diagonal web member. Detailed Implementation

[0034] The present invention will now be described more fully with reference to the accompanying drawings, which illustrate exemplary embodiments of the invention. It should be understood that the present invention can be embodied in many different forms and is not limited to the exemplary embodiments described herein. These embodiments are provided to make the present invention more comprehensive and complete, and to more fully and clearly convey the objectives, specific technical solutions, implementation effects, and advantages of the present invention to those skilled in the art.

[0035] For ease of description, spatial relative terms such as “above,” “below,” “inner,” and “outer” are used here to describe the relationship of one component or feature shown in the figure relative to another component or feature. It should be understood that, in addition to the orientation shown in the figure, spatial terms are intended to include different orientations of the structure in its definition or construction. For example, if the structure in the figure is inverted, a component described as being “below” other components or features would be positioned “above” other components or features; therefore, the exemplary term “below” can include both upper and lower orientations. Structures can be positioned in other ways (rotation, flipping, translation, etc.), and the spatial relative descriptions used herein can be interpreted accordingly.

[0036] The following is combined with Figures 7 to 19 Preferred embodiments of the present invention will be described below. These embodiments are intended to explain the invention and not to limit its scope.

[0037] like Figure 2 , Figures 7 to 19 As shown, the space frame structure of this embodiment includes multiple longitudinal planar trusses 1 (first planar trusses) arranged at intervals along the longitudinal direction and multiple transverse planar trusses 2 (second planar trusses) arranged at intervals along the transverse direction. Each planar truss includes an upper chord, a lower chord, vertical web members 4, and diagonal web members 3. The longitudinal planar trusses 1 and the transverse planar trusses 2 are connected at the intersection nodes to form a spatial force-bearing system. The chords in the two directions (longitudinal lower chord 6 and transverse lower chord 7) are vertically staggered at the intersection nodes to avoid direct collision between the channel-shaped aluminum alloy components in the node area.

[0038] Both the upper chord (8) and lower chord are double-slot aluminum composite chords. The double-slot aluminum composite chord (9) consists of two slotted aluminum alloy members with their webs facing each other back-to-back. The webs of the two slotted aluminum alloy members are parallel to each other, forming an installation gap between them for inserting vertical web members. The slot orientation, section height, flange width, and wall thickness of the double-slot aluminum composite chord can be determined based on chord axial force, bending moment, stability calculations, and node construction requirements.

[0039] At the intersection, the first directional chord and the second directional chord are vertically staggered, so that the double-groove combined chords in the two directions are located at different heights. A common vertical web member passes through the intersection and extends between the two grooved aluminum alloy components of the upper or lower chord, with its sidewall fitting against the inner side of the web of the grooved aluminum alloy component. Two outer connecting plates 10 are respectively fitted against the outer side of the web of the double-groove combined chord, and through stainless steel bolts 5 pass through the outer connecting plates, the web of the grooved aluminum alloy component, and the common vertical web member in sequence, so that the plates form a clamping connection under the action of bolt preload.

[0040] The end of the diagonal web member 3 can extend into the double-groove combined chord members of the adjacent node, and a clamping connection similar to that of the vertical web member is formed by multiple through stainless steel bolts 5 passing sequentially through the outer connecting plate 10, the web of the double-groove aluminum combined chord member 9 and the diagonal web member.

[0041] When larger rectangular or square aluminum alloy tubes are required for the diagonal web members (such as large-section diagonal web members 13), additional connectors 12 can be installed in the node area to accommodate situations where the cross-sectional widths of the vertical web members and diagonal web members do not match. Figure 18 , Figure 19 As shown.

[0042] The double-groove aluminum composite chord is fitted with box-type fittings 11 between its sections. The box-type fittings 11 are located between or on the outside of the two grooved aluminum alloy members and are connected to the two grooved aluminum alloy members by through stainless steel bolts. The number and spacing of the fittings can be determined based on the calculated length, slenderness ratio, branch stability, and overall stability requirements of the double-groove composite chord.

[0043] Aluminum alloy components can be made of 6-series or 7-series structural aluminum alloys, and the grade and heat treatment state should be determined according to the stress of the component, welding avoidance requirements, extrusion processing capability and corrosion resistance requirements.

[0044] When the space frame is used in a low-magnetic environment, fasteners can be made of austenitic stainless steel, titanium alloy, or other low-magnetic alloys with controlled magnetic permeability, and the magnetic properties of the node areas can be randomly inspected after assembly. The term "low magnetic" in this invention refers to reducing structural magnetism through material and construction control, and does not mean that all components are absolutely non-magnetic under any processing condition.

[0045] Vertical and diagonal web members can be calculated as hinged links, or checked as semi-rigid nodes based on the thickness of the connecting plate, bolt preload, slippage, and node rotational stiffness. For structures subjected to cyclic or vibrational loads, fatigue, anti-loosening, and preload relaxation calculations should be performed, and double nuts, locking washers, anti-loosening nuts, or other equivalent anti-loosening measures should be adopted.

[0046] During assembly, drilling, numbering, and pre-assembly of the double-slot aluminum composite chords, vertical web members, diagonal web members, outer connecting plates, and box-type fittings can be completed in the factory first. On site, the vertical web members are inserted into the gaps between the double-slot composite chords, and the planar trusses in the two directions are assembled into a space frame unit according to the staggered relationship of the intersection nodes. Then, the outer connecting plates are installed and through bolts are inserted, followed by the installation of diagonal web members and inter-segment fittings. Finally, the bolts are tightened in stages according to the design sequence and connected to the support nodes.

[0047] During implementation, calculations should be performed on bolt shear resistance, borehole wall bearing capacity, net section tensile strength, tearing, block shear, local bearing capacity, local buckling, reduction of long connection, reduction of filler plate, node slippage, node rotational stiffness, overall stability and branch stability of double-slot aluminum composite chord.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fully bolted truss-type aluminum alloy space frame structure, comprising a plurality of first planar trusses spaced apart along a first direction and a plurality of second planar trusses spaced apart along a second direction, wherein both the first and second planar trusses include an upper chord, a lower chord, vertical web members, and diagonal web members, characterized in that: Both the upper chord and the lower chord are double-groove aluminum composite chords. The double-groove aluminum composite chord consists of two grooved aluminum alloy components arranged back-to-back, with the webs of the two grooved aluminum alloy components parallel to each other and forming an installation gap. The chords of the first planar truss and the second planar truss are vertically staggered at their intersection nodes. A common vertical web extends into the installation gap of the double-groove aluminum composite chord at the intersection node. The intersection node also includes two outer connecting plates located on the outside of the double-groove aluminum composite chord. Multiple through-stainless steel bolts pass sequentially through the outer connecting plates, the webs of the grooved aluminum alloy components, and the common vertical web to clamp and connect the outer connecting plates, the double-groove aluminum composite chord, and the common vertical web. Box-shaped fittings are provided between the sections of the double-groove aluminum composite chord to connect the two grooved aluminum alloy components.

2. The all-bolted truss aluminum alloy space frame structure according to claim 1, characterized in that: The first planar truss and the second planar truss adopt the truss form of Warren planar truss and Pratt planar truss.

3. The all-bolted truss aluminum alloy space frame structure according to claim 1, characterized in that: Both the vertical web members and the diagonal web members are rectangular or square aluminum alloy tubes.

4. The all-bolted truss aluminum alloy space frame structure according to claim 1, characterized in that: The end of the diagonal web member extends into the double-groove aluminum composite chord members of the node, and multiple through stainless steel bolts pass sequentially through the outer connecting plate, the web of the double-groove aluminum composite chord member, and the diagonal web member to form the same clamping connection as the vertical web member.

5. The all-bolted truss aluminum alloy space frame structure according to claim 4, characterized in that: Additional connectors are provided at the ends of the diagonal web members to accommodate situations where the cross-sectional widths of the vertical web members and the diagonal web members are inconsistent.

6. The all-bolted truss system aluminum alloy space frame structure according to claim 1, characterized in that: The box-shaped fitting is a square or rectangular tube fitting, located between the two channel-shaped aluminum alloy components, and connected to the two channel-shaped aluminum alloy components by through stainless steel bolts.

7. The all-bolted truss-type aluminum alloy space frame structure according to any one of claims 1 to 6, characterized in that: The double-groove aluminum composite chord, the vertical web member, and the diagonal web member are made of 6-series or 7-series aluminum alloy.

8. An assembly method for a fully bolted truss-type aluminum alloy space frame structure according to any one of claims 1 to 7, characterized in that, Includes the following steps: Drilling, numbering, and pre-assembly of the double-groove aluminum composite chord, vertical web members, diagonal web members, outer connecting plates, and box-type fittings; Insert the common vertical web member between the two slotted aluminum alloy components of the double-slotted aluminum composite chord; The two planar trusses are assembled into a space frame unit according to the staggered relationship of the intersection nodes; Install the outer connecting plate and insert through stainless steel bolts; Install diagonal bracing and box-type fittings; Tighten the through stainless steel bolts in stages according to the design sequence, and connect the space frame unit to the support node.

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