An aluminum alloy pipe concrete joint of a flange snap connection

Abstract

The flange buckle connection aluminum alloy pipe concrete joint is buckled by a flange upper disc and a flange lower disc, the flange upper disc is provided with an upper steel groove, the flange upper disc is provided with a lower steel groove, the upper steel groove and the lower steel groove are arranged in a cross shape, the two side plates of the lower steel groove protrude upward and are equal in height to the inner edge of the upper steel groove, so that the flange upper disc and the flange lower disc are tightly buckled, the middle part of the flange upper disc and the middle part of the flange lower disc are provided with a combined column connecting hole, the combined column connecting hole is matched with the shape of the combined column and extends a joint in the axial direction of the combined column, the upper steel groove and the lower steel groove are provided with a stiffening rib parallel to the combined column in the axial direction of the combined column, a circular disc face is arranged around each flange disc steel groove and the combined column connecting hole, a plurality of screw holes are arranged in the axial direction of each steel groove, the cross section of the combined column is square, the middle part of each side is recessed inward into an isosceles trapezoid, the long side of the isosceles trapezoid is close to the center of the combined column, the size is matched with the clamping strip and the combined beam interface, so that the clamping strip and the combined beam can be clamped in the combined column.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of building engineering and relates to a flange buckle connected aluminum alloy pipe concrete joint. BACKGROUND

[0002] Due to the dense oxide film on the surface of the aluminum alloy and the extrusion forming manufacturing process, the aluminum alloy structure can avoid the defects of the traditional steel structure, such as complex manufacturing process, long engineering cycle, difficult transportation and hoisting, and easy corrosion. Filling concrete in the aluminum alloy pipe can form an aluminum alloy concrete structure with high bearing capacity, corrosion resistance, simple production, convenient construction and beautiful appearance, which has broad application prospects. However, the strength of the aluminum alloy will be greatly reduced after high temperature, the connection cannot be welded, and the traditional bolt connection method is high in cost and complex in design and construction.

[0003] Therefore, it has become an urgent problem to provide an aluminum alloy pipe concrete joint with high bearing capacity, corrosion resistance, short engineering cycle and simple and convenient construction. SUMMARY

[0004] In order to achieve the above purpose, the application provides a flange buckle connected aluminum alloy pipe concrete joint, the beam column component and the sleeve connecting piece are all produced by the factory, and the site is assembled, which solves the problems of low bearing capacity, easy deformation, high labor cost and difficult construction of the aluminum alloy joint in the prior art.

[0005] A flange buckle connected aluminum alloy pipe concrete joint, the joint is buckled by a flange upper disc 1 and a flange lower disc 2, the flange upper disc 1 is provided with an upper steel groove 11, the flange lower disc 2 is provided with a lower steel groove 21, the upper steel groove 11 and the lower steel groove 21 are arranged in a cross shape, the two side plates 22 of the lower steel groove 21 protrude upward and are equal in height to the inner edge of the upper steel groove 11, so that the flange upper disc 1 and the flange lower disc 2 are tightly buckled, the middle part of the flange upper disc 1 and the flange lower disc 2 is provided with a combined column connecting hole 3, the combined column connecting hole 3 is matched in shape with a combined column 4 and extends an adapter axially to the combined column 4, the upper steel groove 11 and the lower steel groove 21 are provided with stiffening ribs 5 parallel to the combined column 4 along the axial direction of the combined column 4, each flange disc steel groove is provided with a circular disc surface 6 around the combined column connecting hole 3, and a plurality of screw holes are formed in the disc surface along the axial direction of each steel groove;

[0006] The combined column 4 has a square cross section, each edge is recessed inward in the middle part to form an isosceles trapezoid, the long side of the isosceles trapezoid is close to the center of the combined column 4, and the size is matched with a clamping strip 7 and a combined beam interface 8, so that the clamping strip 7 and the combined beam 9 can be clamped tightly in the combined column 4, the middle part of the combined column 4 is provided with a circular hole 10 for placing a steel cage 31 to fill concrete, and the four corners are provided with triangular holes 12 for filling concrete;

[0007] The combined beam 9 has a cross section in the shape of a workpiece, and is provided with a plurality of transverse, longitudinal and inclined supports inside;

[0008] The card strip 7 is hollow and filled with concrete inside.

[0009] Further, the stiffening ribs 5 of the parallel combination column 4 arranged outside the upper steel groove 11 and the lower steel groove 21 are three, with the middle being high and the two sides being low, the width of the beam being consistent with the internal width of the lower steel groove 21, and the height of the beam being consistent with the internal height of the lower steel groove 21.

[0010] Further, the combination beam 9, the combination column 4, and the card strip 7 are all made of aluminum alloy material.

[0011] Further, the combination beam 9, the combination column 4, and the card strip 7 are made by the following method: first, the combination beam, the combination column, and the card strip are designed with molds by an aluminum material processing factory and are extruded into shapes, with the outer section of the card strip being the same as the section of the column slot so that the card strip can be tightly clamped on the column, and the aluminum alloy beam section, the aluminum alloy-concrete combination column section, and the card strip section are as shown in the figure. Next, the beam end is cut and positioned by laser to form a clasp so that it can be tightly clamped with the column slot. A steel reinforcement cage is pre-buried in the aluminum alloy-concrete combination column hole to ensure the connection of the upper and lower columns, that is, the lower column steel reinforcement cage is inserted into the upper column hole when connected, and then concrete is poured; concrete is filled in the card strip aluminum pipe to ensure its stiffness and bearing capacity.

[0012] Further, the flange joint is made by the following method:

[0013] The flange joint and the bolt are made of stainless steel, the inner diameter section of the flange joint is the same as the column section, so that the flange can be clamped on the column; the flange joint is divided into a flange upper disc and a flange lower disc, which are connected by bolts. Four positive directions of the lower disc are left with a lower steel groove with the same length and width as the beam section, so that the beam can be exactly placed in the lower steel groove, and four positive directions of the upper disc are made into an upper steel groove with the same width as the lower steel groove, so that the lower steel groove can be clamped, and the upper and lower steel grooves can form a steel cylinder together with the beam to bear bending moment and shear force after splicing; the steel cylinder has 1 / 4 circular arc stiffening ribs on the upper and lower parts, so that the joint has better energy dissipation performance.

[0014] Advantages

[0015] The characteristics of simple manufacturing of aluminum alloy section are fully utilized, the beam and column sections are designed ingeniously, the flange joint is used to assemble a three-dimensional complex joint, the construction process only needs hoisting and tightening of 24 bolts, which greatly saves human resources, speeds up the project progress, and reduces the construction difficulty.

[0016] The flange joint integrates the design process into product production, the aluminum alloy beam, column, card strip, and flange joint can all realize standardized design, production, and installation, fine work is carried out on high-precision factory machine tools, building design is modularized, the construction process is simplified, and the building form is diversified, which greatly reduces the design and construction difficulty.

[0017] The aluminum alloy pipe and the concrete combination forms a sleeve effect, the concrete is three-dimensionally compressed, the aluminum alloy is in tension, the respective advantages are fully played, the bearing capacity of the concrete is improved, the bearing capacity of the component and the overall rigidity of the joint are further improved, and the low elastic modulus of the aluminum alloy is avoided;

[0018] The steel connecting plate and the 1 / 4 circular arc stiffening rib of the flange buckle joint can play a good energy dissipation effect and have good seismic performance.

[0019] The flange buckle joints are made of aluminum alloy and stainless steel, are beautiful in appearance, have good durability, do not need a decoration process, and reduce maintenance cost.

[0020] After the aluminum alloy beam, column and clamping strip are integrally formed, they are prefabricated in a factory and assembled on site, the formwork procedure is omitted, construction and transportation cost is reduced, and construction is facilitated.

[0021] The flange buckle joint design follows the overall design concept of strong column and weak beam, strong joint and weak component, so that the energy dissipation effect of the flange buckle joint can be fully played in special conditions such as earthquakes, BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a schematic view of a beam, column and clamping strip structure.

[0023] Figure 2 It is a schematic view of a beam, column and clamping strip splicing structure.

[0024] Figure 3 It is a schematic view of a flange plate structure.

[0025] Figure 4 It is a schematic view of a flange plate splicing structure.

[0026] Figure 5 It is a schematic view of an overall splicing process.

[0027] Figure 6 It is a schematic view of an overall splicing structure.

[0028] Figure 7 It is a model of an aluminum alloy joint beam and column created by using SolidWorks.

[0029] Figure 8 It is a contact setting diagram of an overall structure.

[0030] Figure 9 It is a boundary condition setting diagram.

[0031] Figure 10 It is a load condition setting diagram.

[0032] Figure 11 It is a mesh division setting diagram.

[0033] Figure 12 The simulation results are shown in the figure.

[0034] Figure 13 This is a diagram showing the bending moment results.

[0035] Among them, flange upper plate-1, flange lower plate-2, upper steel channel-11, lower steel channel-21, side plate-22, composite column connection hole-3, composite column-4, stiffening rib-5, plate surface-6, clip-7, composite beam interface-8, composite beam-9, round hole-10, steel cage-31, and triangular hole-12. Detailed Implementation

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0037] like Figures 1-13 As shown, an aluminum alloy pipe concrete joint with flange snap-fit ​​connection is disclosed. The joint consists of an upper flange plate and a lower flange plate snap-fit. The upper flange plate is provided with an upper steel channel and a lower steel channel. The upper and lower steel channels are arranged in a cross shape. The two side plates of the lower steel channel protrude upward and are equal in height to the inner edge of the upper steel channel, thereby making the upper flange plate and the lower flange plate snap-fit ​​tightly. The upper flange plate and the lower flange plate are both provided with a combined column connection hole in the middle. The combined column connection hole fits the shape of the combined column and extends into the axial direction of the combined column. The upper steel channel and the lower steel channel are provided with stiffening ribs parallel to the combined column along the axial direction of the combined column. Each flange steel channel and the combined column connection hole are provided with a circular plate surface around the perimeter. The plate surface is provided with multiple bolt holes along the axial direction of each steel channel.

[0038] The composite column has a square cross-section, with an isosceles trapezoid recessed in the middle of each side. The long side of the isosceles trapezoid is close to the center of the composite column, and its size matches the interface of the clip and composite beam, so that the clip and composite beam can be clamped in the composite column. A round hole is opened in the middle of the composite column to place the steel cage and fill it with concrete, and triangular holes are opened at the four corners to fill with concrete.

[0039] The composite beam has an I-shaped cross-section and is internally equipped with multiple transverse, longitudinal, and diagonal supports;

[0040] The card is hollow and filled with concrete.

[0041] Furthermore, the upper and lower steel channels are provided with three parallel composite column stiffening ribs, with the middle one being higher and the two sides lower. The width of the beam is the same as the internal width of the lower steel channel, and the height of the beam is the same as the internal height of the lower steel channel.

[0042] Furthermore, the composite beams, composite columns, and retaining strips are all made of aluminum alloy.

[0043] Further, the combined beam, the combined column, and the clamping strip are made by the following method. First, the combined beam, the combined column, and the clamping strip are extruded by an aluminum factory with a designed mold. The outer section of the clamping strip is the same as the section of the column slot, so that the clamping strip can be tightly clamped on the column. The aluminum alloy beam section, the aluminum alloy-concrete combined column section, and the clamping strip section are shown in the drawings. Next, the beam end is cut by laser positioning to form a clamping buckle, so that it can be tightly clamped with the column slot. The steel cage is embedded in the aluminum alloy-concrete combined column hole to ensure the connection of the upper and lower columns, that is, the lower column steel cage is inserted into the upper column hole, and then the concrete is poured; the concrete is filled in the clamping strip aluminum pipe to ensure its stiffness and bearing capacity.

[0044] Further, the flange node is made by the following method:

[0045] The flange node and the bolt are made of stainless steel. The inner diameter section of the flange node is the same as the column section, so that the flange can be clamped on the column. The flange node is divided into a flange upper disc and a flange lower disc, which are connected by bolts. Four positive directions of the lower disc are provided with lower steel grooves with the same length and width as the beam section, so that the beam can be exactly placed in the lower steel groove. Four positive directions of the upper disc are provided with upper steel grooves with the same width as the lower steel groove, so that the lower steel groove can be clamped. The upper and lower steel grooves can form a steel cylinder after splicing, which can bear bending moment and shear force together with the beam. The steel cylinder has 1 / 4 circular arc stiffening ribs on the upper and lower sides, so that the node has better energy dissipation performance.

[0046] On-site assembly

[0047] When connecting the node on the construction site, first, select a clamping strip with appropriate length, and place the clamping strip into the column slot to fix the position of the node; then place the flange lower disc on the top end of the clamping strip along the slot; then place the beams in four directions into the flange lower disc along the slot; then place the flange upper disc into the flange lower disc along the slot, and tighten the bolts after clamping. After the construction of the node of this layer is completed, place the clamping strip of the upper layer to construct the node of the upper layer.

[0048] Test example:

[0049] I. Geometric model establishment

[0050] The three-dimensional entity model of each part of the aluminum alloy pipe concrete node is created by SolidWorks. The node is assembled and the part interference is checked. After the check is correct, the model is imported into ABAQUS for finite element analysis and calculation, as shown in Figure 7 .

[0051] The specific detailed size is as follows:

[0052] The column height is 2500 mm, the column section is 300 mm x 300 mm, the column wall thickness is 20 mm, the column section center hole diameter is 120 mm, and the column section four corners triangle is a right isosceles triangle with a waist of 70 mm.

[0053] The card slot and the card strip section are both isosceles trapezoids with an upper base of 80 mm, a lower base of 100 mm, and a height of 60 mm. The card strip height is 860 mm, and the pipe wall thickness is 10 mm.

[0054] The beam section length, width and height are 1000 mm x 100 mm x 200 mm, the flange area section height and width are 30 mm x 100 mm, the web area height and width are 140 mm x 80 mm, and the beam section pipe wall thickness is all 3 mm.

[0055] The flange node height is 860 mm, the steel sleeve thickness embedded in the column section is 20 mm. The disc connecting plate diameter is 450 mm, and the thickness is 35 mm. The diameters of the large and small stiffening ribs are 250 mm and 200 mm respectively, and the thicknesses are both 15 mm. The four wall thicknesses of the upper and lower steel grooves after closing are 40 mm, and the wall thicknesses at the occlusion are all 20 mm.

[0056] The bolt diameters are all 20 mm, the lengths are all 90 mm, and they are uniformly arranged on a straight line 30 mm away from the outer wall of the steel groove. The longitudinal reinforcement uses HRB400 φ12, and the stirrup uses HRB335 φ8 with a stirrup interval of 150 mm.

[0057] II. Setting of material properties

[0058] 2.1 Concrete constitutive model

[0059] The concrete used in this model is C30, and the concrete density is set to 2.37 x 10 -9 t / mm 3 in ABAQUS, the elastic modulus is 3 x 10 4 MPa, the Poisson's ratio is 0.16, and the concrete plastic damage (CDP) model is used to describe the stress-strain relationship of concrete. The parameter input values of the concrete plastic damage model are shown in Table 1.

[0060] Table 1 Parameter input values of concrete damage plasticity (CDP) model

[0061]

[0062] Note: f b0 is the initial equivalent biaxial compressive yield stress; f c0 is the initial uniaxial compressive yield stress; k is the ratio of tensile meridian to compressive meridian normal stress.

[0063] The concrete stress input is true stress, the strain input is true plastic strain, the damage input is the damage value calculated according to the energy equivalence principle, and the compression recovery parameter in the tensile damage of concrete is set to 0.2. The stress-strain relationship of C30 concrete in the compression / tension process is obtained according to the calculation formula given in the Code for Design of Concrete Structures GB50010-2010, and the input plastic damage data of concrete is shown in Tables 2-3.

[0064] Table 2 Input values of stress-strain relationship and plastic damage relationship of concrete under compression

[0065]

[0066] Table 3 Input values of stress-strain relationship and plastic damage relationship of concrete under tension

[0067]

[0068] 2.2 Steel reinforcement constitutive model

[0069] The stress-strain relationship of steel reinforcement is determined by using a double-line model. Among them, the longitudinal reinforcement adopts HRB400, the stirrup adopts HRB335, and the material parameters of the steel reinforcement are as follows: the density is 7.8×10 -9 t / mm 3 , the Poisson's ratio is 0.2, and the Young's modulus is 20×10 4 MPa.

[0070] 2.3 Aluminum alloy constitutive model

[0071] This model is based on the research results of Gardner, Ashraf and Han Linhai et al. on the constitutive relationship of aluminum alloy under force process, and the stress-strain behavior of aluminum alloy is described by using Ramberg-Osgood formula and its extended model. The rest of the material parameters of aluminum alloy are as follows: the density is 2.6×10 -9 t / mm 3 , the Poisson's ratio is 0.283, and the Young's modulus is 6.922×10 4 MPa.

[0072]

[0073] 2.4 Stainless steel constitutive model

[0074] According to the curve shape of the actual tensile test of stainless steel specimen, the stress-strain relationship of stainless steel is determined by using a hardening elastic-plastic model, and the mechanical properties of stainless steel are calculated according to the following formula. The rest of the material parameters of stainless steel are as follows: the density is 7.7×10 -9 t / mm 3 , the Poisson's ratio is 0.3, and the Young's modulus is 16×104 MPa.

[0075]

[0076] Three, analysis step

[0077] Considering that the aluminum alloy tube concrete joint model involves multiple low-cycle repeated loading, the dynamic-implicit calculation method is used for the model analysis to facilitate the calculation convergence. The analysis is mainly divided into two steps, in which step 1 is to apply axial force with appropriate axial compression ratio from the top of the column downward, and the analysis time is taken as 1s; and step 2 is to apply vertical low-cycle repeated loading, and the analysis time is taken as 21s.

[0078] Four, contact setting

[0079] As shown in Figure 8 , the binding constraint is used between the concrete and the aluminum alloy column, the concrete and the aluminum alloy tube, the aluminum alloy tube and the aluminum alloy column, the joint and the aluminum alloy column, the hard contact based on the penalty function is used between the upper joint and the lower joint, the bolt and the joint, the joint and the aluminum beam, and the embedded constraint is used between the steel bar and the concrete.

[0080] Five, boundary condition

[0081] The coupling point RP-2 is created at the top of the column to couple the column top surface, the vertical concentrated load is applied through RP-2 to simulate and adjust the axial compression ratio, in which the X and Y directions are fixed, and only the Z direction single degree of freedom is reserved. The coupling point RP-1 is created at the bottom of the column, and the RP-1 is applied with constraints to completely fix the degrees of freedom, which is regarded as rigid connection.

[0082] The vertical low-cycle repeated loading is applied to the coupling points RP-3, RP-4, RP-5 and RP-6 at the end section of the beam to prevent the premature stiffness degradation and damage of the component, and the loading directions applied to the two ends of the coaxial beam are opposite.

[0083] Six, load condition

[0084] As shown in Figure 10 .

[0085] Seven, meshing

[0086] As shown in Figure 11 , the model is reasonably meshed to ensure the calculation accuracy and efficiency, in which the steel bar mesh element adopts two-node linear three-dimensional truss element (T3D2), the aluminum alloy beam and the aluminum alloy column mesh element adopts C3D6 element, and the remaining component mesh element adopts reduced integration three-dimensional solid 8-node element (C3D8R).

[0087] Eight, calculation result

[0088] As shown in Figures 12-13As shown, according to the result of the numerical simulation, it can be seen that the node has the characteristics that the existing aluminum alloy node does not have, that is, stronger energy dissipation performance. In the existing literature and engineering, the connection of the aluminum alloy node mostly adopts mechanical connection modes such as bolts and rivets, and the bolts and rivets are prone to tensile deformation, and in addition, the aluminum alloy structure has the characteristics of low elastic modulus and easy buckling, and under the hysteretic load, a large amount of residual displacement will be generated, so the hysteretic curve shows a very obvious pinch effect, the hysteresis loop is not full, and the energy dissipation performance is very poor. The node connected by the flange buckle not only avoids the problem of bolt slippage deformation, so that the parts are tightly embedded together, but also plays a role of energy dissipation damping, greatly improving the seismic performance of the aluminum alloy structure.

[0089] In addition, the ultimate bearing capacity and bending moment of the flange buckle connected aluminum alloy concrete node can fully meet the construction needs of low-rise and multi-story buildings, and increasing the thickness of the beam pipe and each component can further improve the bearing capacity. The concrete filled in the column greatly strengthens the bearing capacity of the column, and the bearing capacity increases with the thickness of the column aluminum pipe.

[0090] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any change or replacement without creative labor should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be limited by the protection scope defined in the claims.

Claims

1. An aluminum alloy pipe to concrete joint of a flange snap connection, characterized by, The node is buckled by the flange upper disc and the flange lower disc, the flange upper disc is provided with an upper steel groove, the flange lower disc is provided with a lower steel groove, the upper steel groove and the lower steel groove are arranged in a cross shape, the two side plates of the lower steel groove protrude upward and are equal in height to the inner edge of the upper steel groove, so that the flange upper disc and the flange lower disc are tightly buckled, the middle part of the flange upper disc and the middle part of the flange lower disc are provided with a combined column connecting hole, the combined column connecting hole is matched with the shape of the combined column, and a joint extends axially to the combined column, the upper steel groove and the lower steel groove are provided with a stiffening rib parallel to the combined column in the axial direction of the combined column, and each flange disc steel groove is provided with a circular disc face around the combined column connecting hole, and the disc face is provided with a plurality of screw holes in the axial direction of each steel groove; The combined column section is a square, the middle part of each side is recessed inwardly into an isosceles trapezoid, the long side of the isosceles trapezoid is close to the center of the combined column, and the size is matched with the clamping strip and the combined beam interface, so that the clamping strip and the combined beam can be clamped in the combined column, the middle part of the combined column is provided with a round hole for placing a steel cage to fill concrete, and the four corners are provided with triangular holes for filling concrete; The combined beam section is a H-shaped section, and a plurality of transverse, longitudinal and diagonal supports are arranged inside; The clamping strip is hollow and filled with concrete inside.

2. The aluminum alloy tube to concrete joint of claim 1, wherein, The three stiffening ribs parallel to the combined column are arranged outside the upper steel groove and the lower steel groove, the middle rib is high, and the two side ribs are low, the width of the beam is consistent with the internal width of the lower steel groove, and the height of the beam is consistent with the internal height of the lower steel groove.

3. The aluminum alloy tube concrete joint of claim 1, wherein, The combined beam, the combined column and the clamping strip are all made of aluminum alloy material.

4. The aluminum alloy tube concrete joint of claim 1, wherein, The flange node is prepared by the following method: The flange node and the bolt are made of stainless steel, the inner diameter section of the flange node is the same as the section of the column, so that the flange can be clamped on the column; the flange node is divided into a flange upper disc and a flange lower disc, the upper and lower discs are connected by bolts, four positive directions of the lower disc are provided with a lower steel groove with the same length and width as the section of the beam, so that the beam can be placed in the lower steel groove, four positive directions of the upper disc are provided with an upper steel groove with the same width as the width of the lower steel groove, so that the lower steel groove can be clamped, the upper and lower steel grooves can form a steel cylinder together to bear bending moment and shear force after splicing; the steel cylinder is provided with a 1 / 4 circular arc stiffening rib upward and downward, so that the node has better energy dissipation performance.

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