Node connecting structure for steel structure building

Abstract

The invention discloses a hinge joint connecting structure for a steel structure building, which comprises a bottom plate, a hinge unit and a connecting unit, the hinge unit comprises an inner steel ball, a middle steel ball and an outer steel ball shell which are sequentially arranged from inside to outside and are of a hemispherical structure, and the inner steel ball and the outer steel ball shell are welded on the bottom plate; the inner spherical groove of the middle steel ball is in rolling fit with the inner steel ball, the outer spherical surface of the middle steel ball is in rolling fit with the outer steel ball shell, and the bottom surface of the middle steel ball is provided with a conical table which is gradually reduced from top to bottom; the connecting unit comprises a connecting screw and a sleeve, the lower portion of the connecting screw is screwed in the threaded hole, and the upper portion of the connecting screw is fixedly connected with the flange plate. The bottom of the middle steel ball is a small-diameter conical table, the middle steel ball is movably installed between the outer steel ball shell and the inner steel ball, so that the middle steel ball can relatively rotate by a certain angle, the screw can relatively rotate by a designed angle, the limiting hole provides a rotating space for the sleeve, the rotating angle borne by the rod piece is released, and secondary loads are avoided.

Description

Technical Field

[0001] The invention relates to steel structure construction, in particular to a node connection structure used for steel structure buildings. Background Art

[0002] In steel structure buildings, some hinged nodes are usually connected by hinged supports. However, in actual engineering, the existing hinged supports only weaken the bending bearing capacity of the node. This approach is only valid for very small rotations. Excessive rotation will cause damage to the node; and the pin connection can only be rotated in the plane perpendicular to the pin, and cannot be rotated along the plane passing through the center line of the pin. Therefore, it is crucial to reasonably design the structure of the hinged connection node of the steel structure to release the rotation angle caused by the relative movement of the rods. Summary of the invention

[0003] In view of this, the present invention proposes a node connection structure for a steel structure building.

[0004] To achieve the above object, the present invention adopts the following technical solutions: The hinge node connection structure for steel structure buildings described in the present invention comprises a base plate with a mounting hole, a hinge unit arranged on the base plate, and a connection unit connecting the hinge unit and a flange plate of a rod member, wherein the hinge unit comprises an inner steel ball, an intermediate steel ball, and an outer steel ball shell which are sequentially arranged on the base plate from the inside to the outside and are in a hemispherical structure, wherein the inner steel ball, the intermediate steel ball, and the outer steel ball shell are arranged with the same ball center and the ball center is located at the center of the base plate, the inner steel ball and the outer steel ball shell are welded to the base plate, the inner spherical groove of the intermediate steel ball is in rolling cooperation with the inner steel ball, the outer spherical surface of the intermediate steel ball is in rolling cooperation with the inner spherical surface of the outer steel ball shell, and the bottom surface of the intermediate steel ball has a conical platform which gradually becomes smaller from top to bottom; The middle steel ball is provided with a plurality of threaded holes at intervals, and the outer steel ball shell is provided with limiting holes corresponding to each of the threaded holes one by one; the connecting unit includes a plurality of connecting screws and a sleeve sleeved on each of the connecting screws, the lower part of the connecting screw is screwed into the threaded hole and the upper part thereof is fixedly connected to the flange plate; the middle steel ball is provided with mounting grooves corresponding to the upper and lower threaded holes, and the lower part of the sleeve is inserted into the mounting groove.

[0005] The beneficial effect is that the bottom of the middle steel ball of the present invention is a small-diameter conical platform, and the middle steel ball is movably installed between the outer steel ball shell and the inner steel ball, so that the middle steel ball can rotate at a certain angle relative to each other, and can release the angle generated by the relative movement of the rod, avoiding the generation of secondary loads. The middle steel ball of the present invention is fixedly connected to the flange plate of the rod through multiple screws. Since the middle steel ball rotates relative to the center of the ball, the screw can rotate relative to a certain angle, and the limiting hole provides a certain rotation space for the sleeve, so that the angle of rotation of the rod is released.

[0006] Preferably, the angle between the inclined surface of the conical platform and the horizontal plane is α, so that the sleeve rotates ±α around the center of the sphere. In steel structure installation, α of the present invention is preferably 5°.

[0007] Preferably, when the sleeve rotates upward along the center of the ball by α, the intersection point between the sleeve and the outer steel ball shell is point B, and point B is the highest point of the limit hole; when the sleeve rotates downward along the center of the ball by α, the intersection point between the sleeve and the outer steel ball shell is point A, and point A is the lowest point of the limit hole. The angle between the line B between point B and the center of the ball and the line A between point A and the center of the ball is β ; Rotate the connecting line A around the center of the sphere to obtain a conical surface. The angle between the conical surface and the horizontal plane is c ; The center line of multiple limit holes is the connecting circle, and the radius of the connecting circle is r' , the corresponding connecting arc length between two adjacent limiting holes is L n ; The two intersection points of the connecting circle and the limit hole are point C and point D. Point C is at the center of the sphere. O The line between points C and D and the center of the sphere O The included angle of the projection of the line D between them on the horizontal plane is β' ; The radius of the middle steel ball is r 2. The outer diameter of the sleeve is d 0 , then the parameter r 2. r' , β , d 0 and c The following constraint equations are satisfied according to the geometric relationship: t 0 = r 2 × sing ①; d 0 = r 2 ×cos(γ+α) -(r 2 +t)×cos(γ+β-α) ②; r' = r 2 ×cos( c + β / 2) ③; r 2 ×sin( β / 2)= r' ×sin( β' / 2) ④; L n = (90° - β ')× π × r' ÷ 180 ⑤; In the above equations ① to ⑤, t 0 、t , d 0 , L n and α are all known parameters and can be obtained from these equations r 2. γ, β, r' and β ', and then determine the size of the middle steel ball and the position and size of the limit hole.

[0008] Preferably, the radius of the middle steel ball is r 2. The diameter of the inner steel ball is r 1, r 2=3 r 1.

[0009] Compared with the prior art, the present invention movably installs an intermediate steel ball between the hemispherical outer steel ball shell and the inner steel ball, and the bottom of the intermediate steel ball is a small-diameter conical platform, so that the intermediate steel ball can rotate at a certain angle relative to each other, and can release the angle generated by the relative movement of the rod, avoiding the generation of secondary loads. The intermediate steel ball of the present invention is fixedly connected to the flange plate of the rod through multiple screws. Since the intermediate steel ball can rotate relative to its center, the screw can rotate relative to each other at a certain angle, and the limit hole provides a certain rotation space for the sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a structural schematic diagram of the hinged node connection structure of the present invention.

[0011] Figure 2 It is an exploded view of the hinged node connection structure of the present invention.

[0012] Figure 3 It is a schematic diagram of the middle steel ball.

[0013] Figure 4 yes Figure 3 Top view of the .

[0014] Figure 5 is a schematic diagram of the outer steel ball shell (sleeve rotation ±α).

[0015] Figure 6 It is α, γ, β, r' The relative geometric relationship.

[0016] Figure 7 yes t 0 and d 0 The relative geometric relationship.

[0017] Figure 8 yes β ', β, r' and L n Relative geometric relationships. DETAILED DESCRIPTION

[0018] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0019] It should be noted that, in the description of the present invention, relational terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0020] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "connection" that may appear should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] like Figure 1-4 As shown, the hinge node connection structure for steel structure buildings of the present invention comprises a base plate 1 with a mounting hole a, a hinge unit arranged on the base plate 1, and a connection unit connecting the hinge unit and a flange plate 3 of a rod 2 together, wherein the mounting hole a on the base plate 1 allows an anchor bolt to pass through, thereby fixing the base plate 1 on the foundation of the steel structure; the rod 2 is a force-bearing member, and a stiffening plate is arranged between the rod 2 and the flange plate 3; The hinge unit includes an inner steel ball 4, a middle steel ball 5 and an outer steel ball shell 6 which are arranged on the bottom plate 1 from the inside to the outside. The inner steel ball 4, the middle steel ball 5 and the outer steel ball shell 6 are all hemispherical structures and are arranged with the same ball center; the bottom plate 1 is a circular structure, and the ball center of the inner steel ball 4 is OThe center of the circle of the bottom plate 1 coincides with that of the inner steel ball 4, the bottom plane of the inner steel ball 4 is welded to the bottom plate 1, the middle steel ball 5 is provided with an inner spherical groove b which matches with the inner steel ball 4 from the bottom surface upward, and the middle steel ball 5 is covered on the inner steel ball 4 through the inner spherical groove b; the inner diameter of the outer steel ball shell 6 is consistent with the diameter of the middle steel ball 5, the outer steel ball shell 6 is covered on the middle steel ball 5 and the outer steel ball shell 6 and the bottom plate 1 are welded together, the inner spherical groove b of the middle steel ball 5 is rollingly matched with the inner steel ball 4, and the outer spherical surface of the middle steel ball 5 is rollingly matched with the inner spherical surface of the outer steel ball shell 6; the bottom of the middle steel ball 5 has a conical platform with a diameter gradually decreasing from top to bottom, the conical surface of the conical platform extends obliquely from top to bottom to the groove edge of the inner spherical groove b, and the middle steel ball and the bottom plate are clearance matched up and down. Since the middle steel ball 5 is frictionally matched with the outer steel ball shell 6 and the inner steel ball 4 and the bottom diameter of the middle steel ball 5 gradually decreases, the middle steel ball 5 is subjected to force and can rotate at a certain angle between the outer steel ball shell 6 and the inner steel ball 4, providing a basis for releasing the rotation angle generated by the relative movement of the rod 2; The connection unit includes four connection screws 7 and a sleeve 8 sleeved on each connection screw 7. The two ends of the connection screw 7 have threaded sections c. The length of the sleeve 8 is consistent with the length of the connection screw 7 between the two threaded sections c, that is, the length of the sleeve 8 is the same as the length of the non-threaded section c of the connection screw 7. Among them, four threaded holes 9 that match the threaded sections c of the connection screw 7 are evenly spaced along the circumferential direction on the middle steel ball 5, and the middle steel ball 5 is also provided with a mounting groove 10 corresponding to each threaded hole 9 above and below. The aperture of the mounting groove 10 is consistent with the outer diameter of the sleeve 8, so that the lower part of the sleeve 8 can be inserted into the mounting groove 10; the outer steel ball shell 6 is provided with a limiting hole 11 corresponding to each bolt hole above and below, and the size of the limiting hole 11 allows the sleeve 8 to be centered. O The center can be rotated within the designed angle without colliding with the limit hole.

[0022] During the actual installation, first weld the inner steel ball 4 to the base plate 1; screw the threaded end of the lower end of the connecting screw 7 into the threaded hole 9 of the middle steel ball 5 and clamp the sleeve 8 in the corresponding installation groove 10, then put the middle steel ball 5 on the inner steel ball 4 (of course, you can also put the middle steel ball 5 on the inner steel ball 4 first, then screw the connecting screw 7 on the middle steel ball 5 one by one and put a sleeve 8); put the outer steel ball shell 6 on the middle steel ball 5 from top to bottom, and ensure that the sleeve 8 and the connecting screw 7 pass through the limiting hole 11 of the outer steel ball shell 6 upward; then adjust the outer steel ball shell 6 into place and weld it to the base plate 1 to complete the fixed installation of the hinge unit of the present invention. During assembly at the construction site, use the anchor bolts on the foundation to fix the base plate 1 on the foundation; pass the connecting screw 7 through the hole on the flange plate 3 at the end of the rod 2 and screw the nut one by one, and an annular limiting surface is formed between the sleeve 8 and the connecting screw 7, which can limit the flange plate 3 and facilitate fixation.

[0023] The present invention movably installs an intermediate steel ball 5 between the hemispherical outer steel ball shell 6 and the inner steel ball 4. The bottom of the intermediate steel ball 5 is a small-diameter conical platform, so that the intermediate steel ball 5 can rotate at a certain angle relative to each other, and can release the angle generated by the relative movement of the rod 2 to avoid the generation of secondary loads. The intermediate steel ball 5 of the present invention is fixedly connected to the flange plate 3 of the rod 2 through multiple screws. Since the intermediate steel ball 5 can rotate relative to its ball center, the connecting screw can rotate relative to the designed angle, and the limit hole 11 provides a rotation space for the sleeve 8.

[0024] The present invention also proposes a calculation method for each component in the present invention, which specifically includes the following contents: The connecting screw 7 of the present invention is made according to the relevant standards of high-strength bolts. The length of the threaded section c at the lower end of the connecting screw 7 is determined according to the "Technical Specifications for Space Grid Structures". The length of the threaded section c at the upper end of the connecting screw 7 is flexibly determined according to the thickness of the flange plate 3. The length of the middle non-threaded portion is consistent with the length of the sleeve 8. The sleeve 8 is made of round steel pipe. The inner diameter and outer diameter of the sleeve 8 can be determined according to the "High Strength Bolts for Steel Grid Bolt Ball Nodes". d 0 , the top elevation of the sleeve 8 is 10 mm higher than the top elevation of the outer steel ball shell 6; The bottom plate 1 is made of round steel plate, the thickness of which can be determined according to the design force and relevant specifications, and the radius R can meet the requirements of the margin of the mounting hole a (i.e. the bolt hole); The inner steel ball 4 can be made of 45# steel, and its radius is 1 / 3 of the radius of the middle steel ball 5; The middle steel ball 5 is made of 45# steel and its radius is r 2 , the angle between any generatrix of the conical platform of the middle steel ball 5 and the horizontal plane is α, preferably 5°, which is the designed rotatable angle; the bottom of the installation groove 10 of the middle steel ball 5 is a horizontal plane, and the height difference between it and the top of the conical platform is the bottom thickness of the threaded hole 9, and the bottom thickness of the threaded hole meets ≥ the depth of the threaded hole 9 + 20mm, and the depth of the threaded hole 9 meets the relevant requirements of the bolt ball in the "Technical Code for Spatial Grid Structures"; to simplify the calculation, the bottom thickness of the present invention takes into account the height of the conical platform at the bottom of the middle steel ball, recorded as t 0 ,but t 0 > Depth of threaded hole 9 + 20 mm; The outer steel ball shell 6 is made of hot-rolled steel, and the inner radius of the ball shell is equal to the radius of the middle steel ball 5. r 2 , the thickness of the spherical shell tIt can be determined according to the magnitude of the force, and this parameter is a known parameter; the limiting hole 11 on the outer steel ball shell 6 is a large circular hole, and the load between the middle steel ball 5 and the outer steel ball shell 6 is transmitted through the contact surface between the two. To simplify the calculation, the spherical surface above the narrowest position between the limiting holes 11 on the outer steel ball shell 6 (that is, the part above the line connecting the centers of the multiple limiting holes 11) bears all the loads. In actual design, the tensile bearing capacity at the narrowest point between the limiting holes 11 should meet actual needs; wherein, the sleeve 8 is along the center of the sphere. O When the sleeve 8 rotates upward α, the intersection point with the outer steel ball shell 6 is point B, and point B is the highest point of the limit hole 11; O When the ball is rotated downward by α, the intersection point between the ball and the outer steel ball shell 6 is point A, which is the lowest point of the limit hole 11, and point B is the lowest point between the ball and the center of the ball. O The angle between the line B between point A and the line A between point A and the center of the sphere is β ; Draw line A around the center of the sphere O After one rotation, we get a conical surface. The angle between the conical surface and the horizontal plane is c , see Figure 5-7 ; Combination Figure 6 and 8 It can be seen that the line connecting the centers of the four limiting holes 11 is a circle (referred to as a connecting circle), and its radius is r' , the arc length of the corresponding connecting circle between two adjacent limiting holes 11 is L n (i.e., the narrowest arc length between the two limit holes 11, which can be determined according to relevant specifications and is a known parameter); the two intersection points of the connecting circle and the limit hole 11 are respectively recorded as point C and point D, and point C is O The line between points C and D and the center of the sphere O The included angle of the projection of the line D between them on the horizontal plane is β' ; According to the geometric relationship, the above parameters r 2. r' , β , d 0 and c The following constraint equations are satisfied: t 0 = r 2 × sing (Ignore the cone) ①; d 0 = r 2 ×cos( c + α ) - ( r 2+ t )×cos( c + β - α ) ②; r' = r 2 ×cos( c + β / 2) ③; r 2 ×sin( β / 2)= r' ×sin( β' / 2) ④; L n = (90° - β ')× π × r' ÷ 180 ⑤; In the above equations ① to ⑤, t 0 、t , d 0 , L n and α are all known parameters and can be obtained according to the above equation r 2. γ, β, r' and β ', and then determine the radius of the middle steel ball 5 and the relevant parameters of the limiting hole 11, and further determine the radius of the inner steel ball 4 and the outer diameter of the outer steel ball shell 6 according to the radius of the middle steel ball 5. Among them, since the height of the conical platform is very small, it can be ignored in actual calculation, so t 0 is equal to r 2 × sing .

[0025] The present invention reasonably designs the middle steel ball 5 and the limiting hole 11 to ensure that the sleeve 8 does not collide with the outer steel ball shell 6 within the designed rotation angle range, so that the external force received by the rod 2 is released.

[0026] The following is an example of the axial force of the rod 2 being 400KN to verify the present invention: When the axial force of the rod 2 is 400KN, the following known parameters are determined: the outer steel ball shell 6 is made of Q355 steel, with a thickness of t=10mm, a strength design value of f=305MPa, and a narrowest arc length between the limit holes 11 L n =79.5mm; the middle steel ball 5 is made of 45# steel, with a strength design value of f =290MPa; the connecting screw 7 is made of 10.9s high-strength bolt, with a diameter of dis 20 mm, and the strength design value is 500 MPa; d The length of the threaded hole 9 is specified in the specification and the thickness of the bottom of the threaded hole is not less than 20 mm, so t0>44 mm). In this embodiment t 0 Take 53.7mm; the strength design value of the inner steel ball 4 is f = 290MPa; the sleeve 8 is made of Q355 steel, with an inner diameter of 21mm, an outer diameter of 40mm, and a strength design value of f = 305MPa; the design rotation angle α = 5°; According to the known parameters and equations ①~⑤, we can get r 2 =150mm, β =38°, c =21°, r' =116.4 mm, β' =29°, it can be calculated that the outer diameter of the outer steel ball shell 6 is 160mm; c The position of the positioning groove on the middle steel ball can be determined, and the position of the sleeve can be further determined. The sleeve length L≥ r 2+ t +10- r 2×sin(γ+α), that is, L≥104.2mm, in this embodiment, L=105mm, and the radius of the inner steel ball 4 is 50mm.

[0027] The force verification of the connection structure in this specific example is as follows: 1. Tensile calculation The tensile force is directly transmitted from the flange plate 3 to the connecting screw 7, and the connecting screw 7 transmits the force to the outer steel ball shell 6 through the middle steel ball 5, and then to the bottom plate 1 and the foundation by the outer steel ball shell 6. Among them, the compressive bearing capacity of the connecting screw 7 is N 1 is: N1 = cross-sectional area of ​​connecting screw 7 (net area after removing the screw, obtained by looking up the specification) × strength design value == 4 × 245 × 500 = 490KN, which is greater than the axial force of rod 2 and meets the actual needs; Outer steel ball shell 6: The load between the middle steel ball 5 and the outer steel ball shell 6 is transmitted through the contact surface between the two. In order to simplify the calculation, the spherical surface above the narrowest position between the large circular holes on the outer steel ball shell 6 bears all the loads. Then the bearing capacity along the rod 2 direction at the narrowest position is N 2 =L n ×t×f (strength design value of outer steel shell)×cos(γ+β / 2) = 4×79.5×10×305 ×cos(21°+38° / 2) = 743KN>400KN, meeting actual needs; 2. Compression calculation The pressure is directly transmitted from the flange plate 3 to the sleeve 8, and the sleeve 8 transmits the force to the bottom plate 1 and the foundation through the middle steel ball 5 and the inner steel ball 4. Among them, the sleeve 8 is checked for stability according to the axial compression member in the "Steel Structure Design Standard", and is calculated as hinged at both ends. The calculated length is 105mm, and the cross-sectional area of ​​the sleeve 8 = 909.8mm 2 , radius of gyration i =9.99mm, slenderness ratio λ=calculated length / i =10.5, the stability coefficient φ=0.994 is obtained from the table, and the compressive bearing capacity of the sleeve 8 N3=4×0.994×909.8×305 N=1103KN>400KN, which meets the actual needs; The contact area between the inner steel ball 4 and the bottom plate 1 is S = 3.14 × 50 2 = 7850mm 2 , then its compressive bearing capacity N4 = 7850 × 290 N = 2276.5KN>400KN (axial force of rod 2), which meets the actual needs.

[0028] Finally, it should be emphasized that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Therefore, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An articulated node connection structure for a steel structure building, characterized in that: It comprises a bottom plate with a mounting hole, a hinge unit arranged on the bottom plate, and a connecting unit connecting the hinge unit and a flange plate of a rod, wherein the hinge unit comprises an inner steel ball, an intermediate steel ball, and an outer steel ball shell which are arranged on the bottom plate in sequence from the inside to the outside and are in a hemispherical structure, wherein the inner steel ball, the intermediate steel ball, and the outer steel ball shell are arranged with the same ball center and the ball center is located at the center of the bottom plate, the inner steel ball and the outer steel ball shell are welded to the bottom plate, the inner spherical groove of the intermediate steel ball is in rolling cooperation with the inner steel ball, the outer spherical surface of the intermediate steel ball is in rolling cooperation with the inner spherical surface of the outer steel ball shell, and the bottom surface of the intermediate steel ball has a conical platform which gradually becomes smaller from top to bottom; A plurality of threaded holes are arranged at intervals on the middle steel ball, and a limiting hole corresponding to each of the threaded holes is arranged on the outer steel ball shell; the connecting unit comprises a plurality of connecting screws and a sleeve sleeved on each of the connecting screws, the lower part of the connecting screw is screwed into the threaded hole and the upper part thereof is fixedly connected to the flange plate; the middle steel ball is provided with mounting grooves corresponding to the upper and lower threaded holes, and the lower part of the sleeve is inserted into the mounting groove.

2. The hinged node connection structure for steel structure buildings according to claim 1, characterized in that: The angle between the inclined surface of the conical table and the horizontal plane is α, so that the sleeve can rotate ±α around the center of the sphere.

3. The hinged node connection structure for steel structure buildings according to claim 2, characterized in that: When the sleeve rotates upward along the center of the ball by α, the intersection point between the sleeve and the outer steel ball shell is point B, which is the highest point of the limit hole; when the sleeve rotates downward along the center of the ball by α, the intersection point between the sleeve and the outer steel ball shell is point A, which is the lowest point of the limit hole. The angle between the line B between point B and the center of the ball and the line A between point A and the center of the ball is β ; Rotate the connecting line A around the center of the sphere to obtain a conical surface. The angle between the conical surface and the horizontal plane is γ ; The center line of multiple limit holes is the connecting circle, and the radius of the connecting circle is r' , the corresponding connecting arc length between two adjacent limiting holes is L n ; The two intersection points of the connecting circle and the limit hole are point C and point D. Point C is at the center of the sphere. O The line between points C and D and the center of the sphere O The included angle of the projection of the line D between them on the horizontal plane is β' ; The radius of the middle steel ball is r 2. The outer diameter of the sleeve is d 0 , then the parameter r 2. r' , β , d 0 and γ The following constraint equations are satisfied according to the geometric relationship: t 0 = r 2 × sinγ ①； d 0 = r 2 ×cos(γ+α) -(r 2 +t)×cos(γ+β-α) ②； r' = r 2 ×cos( γ + β / 2) ③; r 2 ×sin( β / 2)= r'×sin ( β' / 2) ④; L n =（90°- β '）× π × r' ÷ 180 ⑤； In the above equations ① to ⑤, t 0 、t , d 0 , L n and α All are known parameters.

4. The hinged node connection structure for steel structure buildings according to claim 1, characterized in that: The radius of the middle steel ball is r 2. The diameter of the inner steel ball is r 1, r 2=3 r 1.

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