An assembly node and its design method

Abstract

This invention relates to an assembly node, comprising: a node prism tube and multiple rods, the rods being radially distributed around the axis of the node prism tube. The sidewalls of the node prism tube form multiple connecting surfaces along its circumference. A radially extending anti-shear pin is fixed to the center of each connecting surface. Each rod has an end plate that conforms to the connecting surface, and the end plate has a pin hole in its center for inserting the anti-shear pin. The end plate has an upper ear plate and a lower ear plate extending radially along the rod, and the upper and lower ear plates are fixed to the connecting surfaces by bolts. This invention also discloses a design method for the above-mentioned assembly node.

Description

Technical Field

[0001] This invention relates to the technical field of large-span building structures, and in particular to an assembly node and a design method for the assembly node. Background Technology

[0002] With the widespread development of spatial grid structures, the design and research of prefabricated nodes has always been a hot topic. The German company Mero invented the MeroKK (such as...) in 1942. Figure 1a The MeroKK node (bolted ball node) can be considered the first widely used commercially available spatial grid node. It is constructed by connecting a circular steel pipe to a spherical steel node with bolts. The MeroKK node has tapered ends at the ends of the members connected by a single bolt. The node area has low bending and shear bearing capacity. It is assumed to be a hinged model and is suitable for space frame or double-layer reticulated shell structures, but not for single-layer large-span structures.

[0003] The German company Mero has also developed prefabricated steel joints for single-story, large-span structures, such as the MeroBK (e.g., Figure 1b Types such as ) are used. This type of node has multiple bolts connecting the ends of the members to the node, providing resistance to compression (tension), bending, and shear. Assuming it is a rigid or semi-rigid connection, it can be used in single-story, large-span structures. However, this node has the following disadvantages: 1) To install and inspect the bolts, a partial opening is made at the top of the member, weakening the member's cross-section and bearing capacity, resulting in uneven stress distribution; 2) The internal dimensions of the member's cross-section limit the number of bolts that can be arranged within the member, limiting the bending and shear bearing capacity of the node area. This node is suitable for single-story, large-span structures with low bending moments and shear forces; 3) Bolt installation is inconvenient due to the limitations of the member's internal dimensions.

[0004] The aluminum alloy nodes developed by the American company Temcor (such as...) Figure 2 This design utilizes two independent node disks to connect the upper and lower flanges of the I-shaped aluminum alloy members, and is also suitable for single-layer aluminum alloy grid structures. However, the web of this node member is not connected to the node area, resulting in low bending and shear capacity, making it unsuitable for single-layer, large-span structures with large bending moments and shear forces.

[0005] Domestically, prefabricated steel nodes using spatial grids have also seen development. For example, Fan Feng et al. proposed CP nodes (such as those used in single-story, large-span structures) in patents CN201320749926.1 and CN201310601553.8. Figure 3a ) and C node (such as Figure 3b Currently, this design has not been applied to any engineering projects. The CP node has vertical connecting plates at the ends of the members and in the node area, connected by bolts. Its layout is limited, and its bending capacity is limited. The C node is structurally similar to the MeroBK node, but with an opening added to the lower flange of the member, exhibiting similar shortcomings to the MeroBK node.

[0006] While there are many types of prefabricated spatial grid nodes both domestically and internationally, few prefabricated node types offer high load-bearing capacity, convenient installation, and suitability for single-story, large-span structures. To address this, this patent proposes a novel prefabricated node and its corresponding design method.

[0007] The information disclosed in this background section is intended only to enhance the understanding of the general background of this application 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

[0008] One objective of this invention is to provide an assembly node, and another objective is to provide a design method for an assembly node, so as to solve the technical problems existing in the prior art.

[0009] To solve the above-mentioned technical problems, the present invention provides an assembly node, which includes: a node prism cylinder and multiple rods. The rods are radially distributed around the axis of the node prism cylinder. The sidewalls of the node prism cylinder form multiple connecting surfaces along its circumference. A radially extending anti-shear pin is fixed in the middle of the connecting surface. The end of each rod is provided with an end plate that fits against the connecting surface. The middle of the end plate is provided with a pin hole for inserting the anti-shear pin. The end plate has an upper ear plate and a lower ear plate that extend radially along the rod. The upper ear plate and the lower ear plate are fixed to the connecting surface by bolts.

[0010] Furthermore, the cross-section of the shear pin is in the shape of an "I".

[0011] Furthermore, the pin hole is a square hole.

[0012] Furthermore, the sidewall of the node prism tube has six connecting surfaces; and is equipped with six of the aforementioned rods.

[0013] Furthermore, the upper ear plate and the lower ear plate are respectively fixed to the connecting surface by two horizontally distributed bolts.

[0014] Furthermore, the rod is a rectangular tube with a rectangular cross-section.

[0015] A design method based on the above assembly node, the method includes the following steps:

[0016] S1. Obtain the geometric configuration from the mesh spatial relationship and establish a mesh calculation model with rigidly connected nodal prism tubes;

[0017] S2. Number the node prism tube as N i The component is numbered E j ;

[0018] S3. Solve for the end moments of each member under the combined minor earthquake condition. Axial force Shear force Where k is the ordinal number of the computation iteration;

[0019] S4. Determine the bolt arrangement and specifications based on the bending moment and axial force at the ends of each member, and determine the size and specifications of the shear pins based on the shear force at the ends of each member.

[0020] S5. The arrangement of bolts at the ends of the members meets the requirement of equal bending strength with the corresponding member sections. The height of each node is then calculated.

[0021] S6. Find the local planes formed by adjacent members with nodes as vertices, and obtain the normal vector of each local plane.

[0022] S7. For each normal vector Summing yields the axis vector of the nodal prism tube;

[0023] S8. The plane with the axis of the nodal prism tube as the normal and passing through the vertex is taken as the intermediate plane of each nodal prism tube. Determine the geometric arrangement of each node;

[0024] S9. The projection of the width of the members surrounding the node prism tube onto the intermediate plane is... The projection of the spacing between the members onto the mid-plane is: The projection of the angle between the members onto the mid-plane is

[0025] S10. Find the minimum circumcircle radius of the prism tube at each node. Design geometric conditions for nodal prism tubes;

[0026] S11. Based on experiments and numerical simulations, corresponding different... and Parameter node M ij =f(θ) ij ) Relationship curve, where For the wall thickness of the node, For the wall thickness of the end plate of the member, θ ij Given the relative rotation angle between the j-axis of member and the i-axis of node in the plane of corresponding bending moment action, select nodes that meet the requirements. and The parameters satisfy the condition that the bending moment at the ends of each component is located at M under the combined minor earthquake load case. ij =f(θ) ij The design of the elastic segment of the relationship curve, the node prism tube, and the rods has been completed.

[0027] Furthermore, after step S5, the cross-sections of each of the aforementioned members are verified. Does it meet the requirements for small earthquake combination conditions?

[0028] Furthermore, before the design of the node prism tube and rod is completed, the following steps are also included:

[0029] S12. The elastic stage of the nodal constitutive relationship is simulated using a linear spring combination. The structural model considering the nodal constitutive relationship is verified under various combined working conditions under minor earthquakes.

[0030] S13. Calculate and verify the end moments of the members at each node. Axial force Shear force

[0031] S14. Check whether the cross sections at both ends of the member meet the stress requirements. If not, adjust the member specifications according to the calculation results and return to step S4 to redesign.

[0032] S15. Simultaneously, based on each node M ij =f(θ) ij In the elastic stage of the relationship curve, check whether the nodes meet the stress requirements. If not, adjust the node specifications according to the verification results and return to step S4 to redesign. If both step S4 and step S14 meet the requirements, proceed to step S16.

[0033] S16. The entire stage of the nodal constitutive relationship is simulated using a nonlinear spring combination to perform performance calculations on the structural model considering the nodal constitutive relationship under the time history conditions of major and moderate earthquakes.

[0034] S17. Calculate and verify the end moments of the members at each node. Axial force Shear force

[0035] S18. Check whether the cross sections at both ends of the member meet the performance requirements. If not, adjust the member specifications according to the calculation results and return to step S4 to redesign.

[0036] S19. Simultaneously, based on each node M ij =f(θ) ij The relationship curve is checked at all stages to see if the nodes meet the performance requirements. If not, the node specifications are adjusted according to the verification results, and the design is returned to step S4. If this step and step S18 are satisfied at the same time, the design of the node prism tube and rod is completed.

[0037] By adopting the above technical solution, the present invention has the following beneficial effects:

[0038] The nodes of this invention can adapt to various component forms and sizes, eliminating the need for on-site welding, enabling rapid construction, and reducing construction costs and difficulty. Bolts are set on the upper and lower sides of the end plates of the members without weakening the member cross-section. By adjusting the bolt arrangement and the end plate cross-section, the node can simultaneously transmit axial force, bending moment, and shear force. The bending stiffness and strength of the node can adapt to different engineering requirements, achieving the corresponding bending capacity, and are suitable for various types of single-story large-span structures.

[0039] Meanwhile, by analyzing the mesh geometry, deriving the geometric arrangement relationship between nodes and members, and verifying the stress and performance requirements of nodes and members, a design method for this type of prefabricated node is proposed. Attached Figure Description

[0040] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1a This is a schematic diagram of a MeroKK node in the prior art;

[0042] Figure 1b This is a schematic diagram of a MeroBK node in the prior art;

[0043] Figure 2 This is a schematic diagram of a Temcor node in the prior art;

[0044] Figure 3a This is a schematic diagram of a CP node in the prior art;

[0045] Figure 3b This is a schematic diagram of node C in the prior art;

[0046] Figure 4 This is an isometric view of the novel assembled node in this patent.

[0047] Figure 5 This is an exploded view of the novel prefabricated node in this patent.

[0048] Figure 6 This is a schematic diagram of a single-layer, large-span structure using a novel prefabricated node in this patent.

[0049] Figure 7 This is a plan view of the novel assembled node in this patent;

[0050] Figure 8 for Figure 7 Schematic diagram of the AA section;

[0051] Figure 9 This is a schematic diagram of solving the axial vector of the novel assembled node in this patent;

[0052] Figure 10 This is a schematic diagram of the M-θ curve of the novel assembled node in this patent;

[0053] Figure 11a This is one of the flowcharts for the node design method in this patent;

[0054] Figure 11b This is the second flowchart of the node design method in this patent;

[0055] Figure 12 A schematic diagram of the relative rotation angles of the nodes in this patent;

[0056] Icons: 1. Node prism tube, 2. Rod, 3. End plate, 4. Bolt, 5. Lower ear plate, 6. Upper ear plate, 7. Pin hole, 8. Connecting surface, 9. Shear pin. Detailed Implementation

[0057] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0059] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0060] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0061] Example 1

[0062] like Figure 4 and Figure 5 The diagram illustrates a specific embodiment of an assembly node in this invention. The assembly node in this embodiment specifically includes: a node prism tube 1 and six rods 2. The rods 2 are rectangular tubes with a rectangular cross-section, and are radially distributed around the axis of the node prism tube 1. The sidewalls of the node prism tube 1 form six connecting surfaces 8 along its circumference. A radially extending anti-shear pin 9 is fixed to the center of each connecting surface 8. The anti-shear pin 9 has an "I"-shaped cross-section. The ends of the rods 2 are provided with end plates 3 that fit against the connecting surfaces 8. The center of the end plate 3 is provided with pin holes 7 for inserting the anti-shear pin 9. The pin holes 7 are square holes. The end plate 3 has an upper ear plate portion 6 and a lower ear plate portion 5 extending radially along the rods 2. The upper ear plate portion 6 and the lower ear plate portion 5 are fixed to the connecting surfaces 8 by bolts 4. Specifically, the upper ear plate portion 6 and the lower ear plate portion 5 are respectively fixed to the connecting surfaces 8 by two horizontally distributed bolts 4, thereby fixing the rods 2 to the node prism tube 1.

[0063] The nodes in this embodiment can adapt to various component forms and sizes, eliminating the need for on-site welding, thus enabling rapid construction and reducing construction costs and difficulty. Bolts are installed on the upper and lower sides of the end plates of the members without weakening the member cross-section. By adjusting the bolt arrangement and the end plate cross-section, the node can simultaneously transmit axial force, bending moment, and shear force. The bending stiffness and strength of the node can adapt to different engineering requirements, achieving the corresponding bending capacity, and is suitable for various types of single-story large-span structures.

[0064] Example 2

[0065] like Figure 6 The figure shows a specific embodiment of a single-layer large-span structure based on the assembly node in Embodiment 1. In this embodiment, the single-layer large-span structure specifically includes: a number of node prism tubes 1 arranged in an array, wherein one node prism tube 1 is connected to the six surrounding node prism tubes 1 by a rod 2.

[0066] Example 3

[0067] like Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11a , Figure 11b and Figure 12 The diagram illustrates a design method for an assembly node based on Embodiment 1. In this embodiment, the method includes the following steps:

[0068] P1. Obtain the geometric configuration from the mesh spatial relationship and establish a mesh computation model with rigidly connected nodes;

[0069] P2. Number the node N i The component is numbered E j ;

[0070] P3. Solve for the bending moments at the ends of each member under the combined minor earthquake condition. Axial force Shear force

[0071] P4. Determine the bolt arrangement and specifications based on the bending moment and axial force at the ends of each member, and determine the size and specifications of the shear pins based on the shear force at the ends of each member.

[0072] P5. Verification of the cross-sections of each component. It meets the requirements for minor earthquake combined working conditions;

[0073] P6. The arrangement of bolts at the ends of the members meets the requirement of equal bending strength with the corresponding member sections. The height of each node is then calculated. ( Figure 8 );

[0074] P7. Find the local planes formed by adjacent members with nodes as vertices, and find the normal vector of each local plane.

[0075] P8. For each normal vector Summing yields the axis vector of the node. Figure 9 );

[0076] P9. The plane with the axis direction as normal and passing through the vertex is taken as the intermediate plane of each node. Determine the geometric arrangement of each node;

[0077] P10. The projection of the width of the members surrounding the node onto the intermediate plane is: The projection of the spacing between the members onto the mid-plane is: The projection of the angle between the members onto the mid-plane is ( Figure 7 );

[0078] P11. Find the minimum circumcircle radius of each node. Design geometric conditions for nodes;

[0079] P12. Based on experiments and numerical simulations, give the corresponding different... and Parameter node M ij =f(θ) ij Relationship curve, select nodes that meet the requirements. and The parameters satisfy the condition that the bending moment at the ends of each component is located at M under the combined minor earthquake load case. ij =f(θ) ij The elastic segment of the relationship curve ( Figure 10 );

[0080] P13. The elastic stage of the nodal constitutive relationship is simulated using a linear spring combination. The structural model considering the nodal constitutive relationship is verified under various combined working conditions under minor earthquakes.

[0081] P14. Calculate and verify the end moments of the members at each node. Axial force Shear force

[0082] P15. Check whether the cross sections at both ends of the member meet the stress requirements. If not, adjust the member specifications according to the calculation results and return to step P4 to redesign.

[0083] P16. Simultaneously, based on each node M ij =f(θ) ij In the elastic stage of the relationship curve, check whether the nodes meet the stress requirements. If not, adjust the node specifications according to the verification results and return to step P4 to redesign. If both step P4 and step P15 meet the requirements, proceed to step P17.

[0084] P17. The entire stage of the nodal constitutive relationship is simulated using a nonlinear spring combination. The performance of the structural model considering the nodal constitutive relationship is calculated under the time history conditions of major and moderate earthquakes.

[0085] P18. Calculate and verify the end moments of the members at each node. Axial force Shear force

[0086] P19. Check whether the cross sections at both ends of the member meet the performance requirements. If not, adjust the member specifications according to the calculation results and return to step P4 to redesign.

[0087] P20. Simultaneously, based on each node M ij =f(θ) ij The relationship curve is checked at all stages to see if the nodes meet the performance requirements. If not, the node specifications are adjusted according to the verification results, and the design is re-entered in step P4. If both step P4 and step P19 meet the requirements, proceed to step P21.

[0088] P21. Node and component design completed.

[0089] This embodiment proposes a design method for prefabricated nodes by analyzing the mesh geometry, deriving the geometric arrangement relationship between nodes and members, and verifying the stress and performance requirements of nodes and members.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An assembly node, characterized by The assembly node includes: a node prism tube and multiple rods. The rods are radially distributed around the axis of the node prism tube. The sidewalls of the node prism tube form multiple connecting surfaces along its circumference. A radially extending anti-shear pin is fixed in the middle of the connecting surface. The end of each rod is provided with an end plate that fits against the connecting surface. The middle of the end plate is provided with a pin hole for inserting the anti-shear pin. The end plate has an upper ear plate and a lower ear plate that extend radially along the rod. The upper ear plate and the lower ear plate are fixed to the connecting surface by bolts. The cross-section of the shear-resistant pin is shaped like an "I". The pin hole is a square hole; The sidewall of the node prism tube has 6 connecting surfaces; it is equipped with 6 of the aforementioned rods; The upper ear plate and the lower ear plate are respectively fixed to the connecting surface by two horizontally distributed bolts; The rod is a rectangular tube with a rectangular cross-section.

2. A method of designing an assembly node based on the design of claim 1, characterized in that, The method includes the following steps: S1. Obtain the geometric configuration from the mesh spatial relationship and establish a mesh calculation model with rigidly connected nodal prism tubes; S2. Number the node prisms as N i , number the components as E j ; S3. Solving each of the rod end moment under small earthquake combination working condition axial force shear force where k is the ordinal number of the calculation iteration; S4. Determine the bolt arrangement and specifications based on the bending moment and axial force at the ends of each member, and determine the size and specifications of the shear pins based on the shear force at the ends of each member. S5. The bolt arrangement of the end of the rod satisfies the equal strength requirement of the corresponding rod section bending resistance, and the height of each node is obtained S6. Obtain the local plane with the node as the vertex and the adjacent bars as the sides, and obtain the normal vector of each local plane S7. Summing the normal vectors to obtain the axis vector of the node prism cylinder; S8. A plane that is normal to the axis direction of the node prism cylinder and passes through the vertex is taken as the middle plane of each node prism cylinder determining the geometric arrangement of the nodes; S9. The width of the rods around the node prism cylinder is projected on the midplane as The distance between the rods is projected on the midplane as The angle between the rods is projected on the midplane as S10. Find the minimum circumscribed circle radius of each node prism as the design geometry of the node prism S11. According to the test and numerical simulation, the node M and parameter corresponding to different ij θ ij relationship curve is given, wherein is the wall thickness of the node, is the wall thickness of the end plate of the bar, θ ij is the relative angle of the axis of the bar j and the axis of the node i in the plane corresponding to the bending moment, the node and parameters that meet the requirements are selected, the end bending moment of each component under the small earthquake combination working condition is located in the elastic section of the M ij =f(θ ij ) relationship curve, and the node prism cylinder and the bar are designed.

3. The method of designing according to claim 2, wherein, After the S5 step, check each of the bar sections Whether the small earthquake combination working condition requirement is met.

4. The method of designing according to claim 3, wherein, Before the design of the node prism tube and rod is completed, the following steps are also included: S12. The elastic stage of the nodal constitutive relationship is simulated using a linear spring combination. The structural model considering the nodal constitutive relationship is verified under various combined working conditions under minor earthquakes. S13. Calculate the end moment of each member of each node Axial force Shear force S14. Check whether the cross sections at both ends of the member meet the stress requirements. If not, adjust the member specifications according to the calculation results and return to step S4 to redesign. S15. Meanwhile, according to each node M ij = f (θ ij ) relationship curve elastic stage check whether the node meets the force, if not, according to the calculation results adjust the node specification, return to step S4 to redesign, if the step S14 and S14 at the same time, enter S16 step; S16. The entire stage of the nodal constitutive relationship is simulated using a nonlinear spring combination to perform performance calculations on the structural model considering the nodal constitutive relationship under the time history conditions of major and moderate earthquakes. S17. Calculate the checking to get the corresponding node of the end of the member bending moment Axial force Shear force S18. Check whether the cross sections at both ends of the member meet the performance requirements. If not, adjust the member specifications according to the calculation results and return to step S4 to redesign. S19. Meanwhile, according to each node M ij = f(θ ij ) relationship curve full stage check whether the node meets the performance requirements, if not, according to the calculation results adjust the node specification, return to step S4 to re-design, if the step and the step S18 at the same time meet, the node prism cylinder and the rod design is completed.

Images