Reinforced joint of crossed concrete filled steel tubular column for cooling tower based on equal-strength design

Abstract

The utility model discloses a reinforced node of a crossed concrete filled steel tubular column for a cooling tower based on equal strength design, the reinforced node comprises four steel pillars, a radial reinforcing plate and a reinforcing ring, the four steel pillars are welded to form the crossed steel tubular node of an X-shaped structure, the middle position of the crossed steel tubular node is provided with a round-end-shaped steel tube outer package, and the steel tube outer package is connected with the reinforcing ring. More than three reinforcing rings are uniformly arranged in the round-end-shaped outer steel pipe along the height direction, a radial reinforcing plate is arranged at the middle position in the round-end-shaped outer steel pipe, each reinforcing ring is respectively welded with the radial reinforcing plate, and concrete is filled in the four steel supporting columns and the round-end-shaped steel pipe. According to the reinforcing joint type, the cross section is the same and the strength is equal in the height direction in the crossed area, the reinforcing joint is not provided with stiffening ribs in the steel pipe, the situation that a plurality of welding seams intersect with one another is avoided, the construction process is simplified, and manufacturing is easy.

Description

Technical Field

[0001] The utility model discloses a steel tube concrete column reinforced node, in particular a cross steel tube concrete column reinforced node for a cooling tower based on equal strength design, belongs to the technical field of industrial building cooling towers, and is particularly suitable for a super large cooling tower structure using cross steel tube concrete columns. Background Art

[0002] Cross-steel tube concrete reinforced nodes refer to the reinforcement design of the connection nodes in the cross-steel tube concrete components, which are usually used to improve the seismic performance or bearing capacity of cross-steel tube concrete components.

[0003] Existing technologies for enhanced nodes that can be documented include the following:

[0004] (1) Please see the attached Figure 1 The patent document with publication number CN105484368 B proposes an intersecting node with internal reinforcement of cross steel tube concrete. The node reinforcement forms include: two semi-annular connecting plates and an elliptical connecting plate are welded in the middle part of the elliptical connecting plate to form a cross plate; four round steel tubes are welded to the elliptical plate and the annular connecting plate at the four corners of the cross plate; the annular inner stiffening plate is welded to the inner wall of the round steel tube and the elliptical plate; the vertical stiffening plate is welded to the annular stiffening plate, the annular connecting plate and the inner wall of the round steel tube; the outward extending bracket is welded to the outer wall of the steel tube.

[0005] (2) Please see the attached Figure 2 In the patent application documents with publication numbers CN110108151A and CN210004859U, a reinforced steel tube concrete X-pillar is proposed, and the node reinforcement measures include: a tie plate, an annular reinforcement plate and a stiffening plate. The tie plate is arranged at the mutual connection of the four steel tube limbs, and the tie plate and the four steel tube limbs are connected by welding; the annular reinforcement plate is arranged at the periphery of the connection of the four steel tube limbs; the stiffening plate is arranged between adjacent annular reinforcement plates, and the stiffening plate is arranged along the radial and axial direction of the steel tube limbs, and is welded to the steel tube limbs and the annular reinforcement plate.

[0006] (3) Please see the attached Figure 3 The patent with publication number CN208363297U proposes a connection node structure between circular concrete-filled tube columns and square concrete-filled tube columns. Circumferential stiffening ribs are set within 200mm of the intersection of circular concrete-filled tube columns, and circumferential stiffening ribs or transverse stiffening ribs are set within 200mm of the intersection of giant square concrete-filled tube columns and circular steel tube diagonal braces. Longitudinal stiffening ribs are set in circular concrete-filled tube columns, square concrete-filled tube columns and circular steel tube diagonal braces, and their length range is not less than the distance between the circumferential stiffening ribs.

[0007] The above-mentioned existing similar technologies generally have the following problems: (1) The cross-section of the existing cross-steel tube concrete column node area changes continuously along the height direction, forming local variable stiffness and strength. The existing node reinforcement forms all strengthen the node without changing the cross-section of the component. The variable cross-section increases the difficulty of evaluating the strength of the node area, resulting in uneven reinforcement (local over-reinforcement or insufficient reinforcement) in the existing node reinforcement method. (2) The existing node reinforcement form requires the arrangement of transverse, longitudinal or circumferential stiffening ribs in the steel tube. The number of welds is large and staggered horizontally and vertically, the structure is complex and causes inconvenience in construction. The welding stress distribution of steel components in the node area is complex, and it is easy to produce structural weak parts caused by welding stress. (3) For the convenience of construction, most of the existing reinforced node forms expose the reinforcement components such as reinforcement rings to the outside of the steel tube. The complex reinforcement components reduce the overall aesthetics of the component, thereby affecting the overall aesthetics of the building. Summary of the invention

[0008] In view of the shortcomings of the above-mentioned prior art that the crossed steel tube concrete reinforced nodes are prone to uneven reinforcement, complex regional steel member welding stress distribution, and poor overall aesthetics, the utility model provides a crossed steel tube concrete column reinforced node for cooling towers based on equal strength design, which adopts a round-ended steel tube outsourcing method with radial reinforcement plates and reinforcement rings to strengthen the crossed steel tube nodes, thereby solving the problems of local variable stiffness and variable strength in the prior art.

[0009] The utility model adopts the following technical solution to solve the technical problem: a cross steel tube concrete column reinforced node for a cooling tower based on equal strength design, the reinforced node comprising four steel pillars, radial reinforcement plates and reinforcement rings, the four steel pillars are welded to form a cross steel tube node with an "X"-shaped structure, a round-end steel tube outer package is arranged in the middle position of the cross steel tube node, more than three reinforcement rings are evenly arranged inside the round-end outer steel tube along the height direction, a radial reinforcement plate is arranged in the middle position inside the round-end outer steel tube, each reinforcement ring is welded to the radial reinforcement plate respectively, and concrete is filled inside the four steel pillars and the round-end steel tube.

[0010] The technical solution adopted by the utility model to solve its technical problems further includes:

[0011] The steel pillars are made of round steel pipes, the four round steel pipes are respectively a first round steel pipe, a second round steel pipe, a third round steel pipe and a fourth round steel pipe, the crossing angle formed between the first round steel pipe and the second round steel pipe is α, and the α angle is 15°~30°.

[0012] The radial reinforcement plate is rectangular in shape as a whole, and is arranged along the short axis of the round-end outer steel pipe and at the middle position inside the round-end outer steel pipe.

[0013] The round-end outer steel tube is formed by splicing four parts, namely the first round-end outer steel tube, the second round-end outer steel tube, the third round-end outer steel tube and the fourth round-end outer steel tube. The first round-end outer steel tube, the second round-end outer steel tube, the third round-end outer steel tube and the fourth round-end outer steel tube each occupy 1 / 4 of the round-end outer steel tube, and the four parts are welded to form an integral round-end outer steel tube.

[0014] The reinforcement ring is arranged inside the round-end outer steel pipe, a single reinforcement ring is in the shape of a round-end ring, and the outer side of the reinforcement ring is welded to the inner side wall of the round-end outer steel pipe.

[0015] The reinforcement ring is composed of a left part and a right part, and the left part and the right part are respectively welded to the radial reinforcement plate.

[0016] The bottom cut surfaces of the first round steel tube and the second round steel tube are welded together with the top surface of the topmost reinforcement ring, and the top cut surfaces of the third round steel tube and the fourth round steel tube are welded together with the bottom surface of the bottommost reinforcement ring; the radial reinforcement plates extend upward and downward respectively, extending to the top of the topmost reinforcement ring and the bottom of the bottommost reinforcement ring, and the side cut surfaces of the first round steel tube, the second round steel tube, the third round steel tube and the fourth round steel tube are respectively welded together with the corresponding sides of the radial reinforcement plates.

[0017] The beneficial effects of the utility model are as follows: the utility model proposes a reinforced node based on equal strength for the weak parts of the intersection nodes of the cross steel tube concrete columns of the super-large cooling tower structure. The node has the following advantages: (1) The reinforced node type forms a cross section with the same height direction and equal strength in the intersection area, which solves the problem of local variable stiffness and strength in the prior art. The node reinforcement type with equal cross section and equal strength reduces the difficulty of evaluating the strength of the node area and avoids the situation of uneven reinforcement (local over-reinforcement or insufficient reinforcement) in the reinforcement method. (2) The reinforced node does not have stiffening ribs inside the steel pipe, which avoids the situation of multiple welds crossing each other, simplifies the construction process, and is simple to manufacture. At the same time, the reinforcement parts are not exposed outside the components, and the shape is beautiful. (3) The reinforced node meets the design criteria of "strong node and weak component" and is safe and reliable.

[0018] The utility model will be further described below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the existing reinforced node form in the patent document with publication number CN105484368 B (the figure marks are deleted in the figure, and the content of the figure is retained).

[0020] Figure 2This is a schematic diagram of the existing reinforced node form in the patent documents with publication numbers CN110108151A and CN210004859U (the figure marks are deleted in the drawings, and the content of the drawings is retained).

[0021] Figure 3 This is a schematic diagram of the existing reinforced node form in the patent document with publication number CN208363297U (the figure marks are deleted in the figure, and the content of the figure is retained).

[0022] Figure 4 It is a schematic diagram of the three-dimensional structure of the utility model.

[0023] Figure 5 It is a schematic diagram of the structure of the utility model in the exploded state.

[0024] Figure 6 It is a schematic diagram of the longitudinal section structure of the utility model.

[0025] Figure 7 It is a schematic diagram of the transverse cross-sectional structure of the utility model.

[0026] Figure 8 This is a schematic diagram of the node force of the utility model.

[0027] Fig. 9 It is a schematic diagram of the dimensions of the round-end concrete-filled steel tube of the utility model.

[0028] Fig.10 This is a schematic diagram of the dimensions of the reinforcement ring of the utility model.

[0029] In the figure, 1-first round steel tube, 2-second round steel tube, 3-third round steel tube, 4-fourth round steel tube, 5-radial reinforcement plate, 6-reinforcement ring, 7-first round-end shaped outer steel tube, 8-second round-end shaped outer steel tube, 9-third round-end shaped outer steel tube, 10-fourth round-end shaped outer steel tube. DETAILED DESCRIPTION

[0030] This embodiment is a preferred implementation mode of the utility model. Other embodiments whose principles and basic structures are the same or similar to those of this embodiment are within the protection scope of the utility model.

[0031] Based on the equal strength design principle, the utility model proposes a steel tube concrete reinforced node form, which is used to strengthen the weak parts of the cross steel tube concrete column structure and realize the structural design principle of "strong node, weak member".

[0032] Please refer to the attached Figure 4 To Attachment Figure 7The utility model protects a cross steel tube concrete column reinforced node for a cooling tower based on equal strength design, which can be artificially defined as a component area and an equal cross-section node reinforcement area. The reinforced node includes four steel pillars, a radial reinforcement plate 5 and a reinforcement ring 6. In this embodiment, the steel pillars are round steel pipes. In specific implementation, other pillar steel structures such as square steel, channel steel, and I-beam can also be used. The four round steel pipes are respectively a first round steel pipe 1, a second round steel pipe 2, a third round steel pipe 3, and a fourth round steel pipe 4. The four round steel pipes are cut and then welded according to actual use to form a cross steel pipe node of an "X"-shaped structure. The intersection angle formed between the two steel pipes located at the top, namely the first round steel pipe 1 and the second round steel pipe 2, is α, α It changes with the shape of the cooling tower. In this embodiment, the angle α is 15°~30°. Due to the reduction of the cross-section of the node area of ​​the cross-steel pipe, the bearing capacity is reduced, forming a weak part. In order to achieve equal cross-section and equal strength in the node area, the utility model proposes a simple, concise and beautiful reinforcement method for the node area that needs to be strengthened in the cross-steel tube concrete. The node reinforcement method mainly adopts the equal cross-section node reinforcement area to be wrapped by a steel pipe with a round end cross section, and three or more reinforcement rings 6 are evenly distributed in the height direction inside the round end outer steel pipe. The number and size of the reinforcement rings 6 are determined by calculation. A radial reinforcement plate 5 is set in the middle position inside the round end outer steel pipe, and each reinforcement ring 6 is welded to the radial reinforcement plate 5. Among them, the first round steel pipe 1, the second round steel pipe 2, the third round steel pipe 3 and the fourth round steel pipe 4 are component areas, and the round end steel pipe and the radial reinforcement plate 5 and reinforcement ring 6 inside it are equal cross-section node reinforcement areas.

[0033] In this embodiment, the connection parts of the first round steel tube 1, the second round steel tube 2, the third round steel tube 3 and the fourth round steel tube 4 are formed by cutting, and the cutting is performed in the vertical direction and the horizontal direction respectively. In specific implementation, the round-end outer steel tube (i.e., the first round steel tube 1, the second round steel tube 2, the third round steel tube 3 and the fourth round steel tube 4) can also be rolled from steel plates, and the two round-end outer steel tube methods can be selected according to the difficulty of actual engineering construction.

[0034] In this embodiment, the reinforcing steel plate outside the intersection plane is defined as a radial reinforcing plate 5 in the utility model because it is in the same radial direction as the cooling tower. The radial reinforcing plate 5 is rectangular as a whole and is arranged along the short axis of the round-end outer steel pipe.

[0035] In this embodiment, the uniform cross-section node reinforcement area includes a radial reinforcement plate 5, a round-end outer steel tube and more than three reinforcement rings 6. The radial reinforcement plate 5 is arranged along the short axis of the round-end outer steel tube and is arranged in the middle position inside the round-end outer steel tube. The round-end outer steel tube is composed of four parts, namely a first round-end outer steel tube 7, a second round-end outer steel tube 8, a third round-end outer steel tube 9 and a fourth round-end outer steel tube 10. The first round-end outer steel tube 7, the second round-end outer steel tube 8, the third round-end outer steel tube 9 and the fourth round-end outer steel tube 10 each occupy 1 / 4 of the round-end outer steel tube. The four parts are welded to form an integral round-end outer steel tube. The reinforcement ring 6 is arranged inside the round-end outer steel tube. In this embodiment, a single reinforcement ring 6 is in the shape of a round-end ring. The outer side of the reinforcement ring 6 is welded to the inner side wall of the round-end outer steel tube. The width of the reinforcement ring 6 and the distance between adjacent reinforcement rings 6 can be determined by calculation. In this embodiment, a single reinforcement ring 6 is composed of a left part and a right part, and the left part and the right part are respectively welded to the radial reinforcement plate 5 and spliced ​​to form the reinforcement ring 6.

[0036] Since the connection parts of the first round steel tube 1, the second round steel tube 2, the third round steel tube 3 and the fourth round steel tube 4 are formed by cutting in the vertical direction and the horizontal direction respectively, the bottom cutting surfaces (i.e., the bottom surfaces) of the first round steel tube 1 and the second round steel tube 2 are welded to the top surface of the uppermost reinforcement ring 6, and the top cutting surfaces (i.e., the top surfaces) of the third round steel tube 3 and the fourth round steel tube 4 are welded to the bottom surface of the lowermost reinforcement ring 6; the radial reinforcement plate 5 extends upward and downward respectively, extending out to the top of the uppermost reinforcement ring and the bottom of the lowermost reinforcement ring respectively, and the side cutting surfaces of the first round steel tube 1, the second round steel tube 2, the third round steel tube 3 and the fourth round steel tube 4 are respectively welded to the corresponding sides of the radial reinforcement plate 5.

[0037] In this embodiment, the interiors of the first round steel tube 1 , the second round steel tube 2 , the third round steel tube 3 , the fourth round steel tube 4 , and the round-end steel tubes are all filled with concrete.

[0038] Please refer to the attached Figure 8 To Attachment Fig.10 The utility model discloses a design method for a reinforced node of a cross steel tube concrete column for a cooling tower based on equal strength design. According to the design principle of "strong node, weak component", the reinforced node area can be designed according to the principle that the cross-sectional bearing capacity of the node area should be greater than the bearing capacity of the component area under axial compression. The design method includes the following steps:

[0039] Step S1: Design a single leg: According to the bending moment transmitted from the tower to the pillar M and axial force N(i.e., the external load on the pillar), the single-leg concrete-filled steel tube cross section is designed according to the national standard "Technical Specification for Concrete-Filled Steel Tube Structures" GB 50936-2014, and the axial compressive bearing capacity of the single-leg concrete-filled steel tube is calculated. N u ;

[0040] Step S2: Calculate the total bearing capacity of the node: Please refer to the attached Figure 8 , the force at the node is Figure 8 As shown in the attached figure, it can be seen that the bearing capacity of the reinforced node F u The following formula (1) should be satisfied:

[0041] (1)

[0042] Step S2: Decomposition of total node bearing capacity: Total bearing capacity of reinforced nodes F u It consists of the following parts: (1) Bearing capacity of round-ended concrete-filled steel tube section F u1 ; (2) The increase in bearing capacity caused by the strengthening effect of the reinforcing ring 6 on the steel pipe hoop F u2 ; (3) Bearing capacity of radial reinforcement plate 5 F u3 , total bearing capacity of reinforced nodes F u The following formula (2) should be satisfied:

[0043] (2)

[0044] in:

[0045] (1) Bearing capacity of round-ended concrete-filled steel tube cross section F u1 Please refer to the attached Fig. 9 , F u1 It can be calculated by the following formula (3):

[0046] r (3)

[0047] In the formula, A c is the concrete cross-sectional area, in mm 2 ; f c is the design strength of concrete, in MPa; D is the diameter of the round end, in mm; B is the length of the round end section, in mm; θ is the hoop coefficient, ; A s is the cross-sectional area of ​​the steel pipe, in mm 2 ; f s It is the yield strength of steel pipe, in MPa.

[0048] (2) Increased bearing capacity due to the enhanced effect of the reinforcing ring 6 on the steel pipe hoop F u2 In the process, the reinforcement ring can enhance the effect of the steel pipe hoop by the reinforcement coefficient k e To express, k e The calculation method can be obtained by the following formula (4):

[0049] (4)

[0050] In the formula, η 2 is the enhancement factor, ; η 3 is the enhancement factor, ; w is the width of the transverse ring plate, in mm; h is the spacing between the transverse ring plates, in mm.

[0051] Therefore, the increased bearing capacity caused by the strengthening effect of the reinforcement ring on the steel pipe hoop is F u2 It can be calculated by the following formula (5):

[0052] (5)

[0053] (3) Bearing capacity of radial reinforcement plate 5 F u3 In the figure, since the radial reinforcement plate 5 runs through the node height direction, its thickness has a great influence on the node bearing capacity and is an important reinforcement measure for the node. The bearing capacity of the radial reinforcement plate 5 can be directly superimposed on the bearing capacity of the round-end steel tube concrete. The bearing capacity of the radial reinforcement plate 5 can be calculated by the following formula (6):

[0054] (6)

[0055] In the formula, t p is the thickness of the radial reinforcing plate 5, in mm.

[0056] In summary, the bearing capacity of the reinforced node F u Can be F u1 ,F u2 , F u3 Add them together to get, please refer to the following formula (7):

[0057] (7)

[0058] Step S4, design nodes: Based on the design principle of “strong nodes and weak components”, the intersection of steel tube concrete columns is calculated and designed by combining formulas (1) to (6).

[0059] The utility model proposes a reinforced node based on equal strength for the weak intersection nodes of the cross steel tube concrete columns of the super-large cooling tower structure. The node has the following advantages:

[0060] (1) This reinforced node type forms a cross-section with the same height direction and equal strength in the intersection area, which solves the problem of local variable stiffness and strength in the prior art. The node reinforcement type with equal cross-section and equal strength reduces the difficulty of evaluating the strength of the node area and avoids the situation of uneven reinforcement (local over-reinforcement or insufficient reinforcement).

[0061] (2) The reinforced node does not have stiffening ribs inside the steel pipe, which avoids the situation where multiple welds intersect each other, simplifies the construction process, and is easy to manufacture. At the same time, the reinforcement parts are not exposed outside the component, and the shape is beautiful.

[0062] (3) The reinforced node meets the design principle of “strong node and weak component” and is safe and reliable.

Claims

1. A cross steel tube concrete column reinforced node for a cooling tower based on equal strength design, characterized by: The reinforced node comprises four steel pillars, radial reinforcement plates (5) and reinforcement rings (6); the four steel pillars are welded to form an "X"-shaped cross-steel tube node; a round-end steel tube outer package is arranged in the middle of the cross-steel tube node; more than three reinforcement rings (6) are evenly arranged inside the round-end outer steel tube in the height direction; a radial reinforcement plate (5) is arranged in the middle of the round-end outer steel tube; each reinforcement ring (6) is welded to the radial reinforcement plate (5); and the inside of the four steel pillars and the inside of the round-end steel tube are filled with concrete.

2. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 1 is characterized in that: The steel support column is made of round steel pipes, wherein the four round steel pipes are respectively a first round steel pipe (1), a second round steel pipe (2), a third round steel pipe (3) and a fourth round steel pipe (4), and a crossing angle α formed between the first round steel pipe (1) and the second round steel pipe (2) is 15° to 30°.

3. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 2 is characterized in that: The radial reinforcement plate (5) is rectangular in shape as a whole, and is arranged along the short axis of the round-end shaped outer steel pipe, and is arranged at a middle position inside the round-end shaped outer steel pipe.

4. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 2 is characterized in that: The round-end shaped outer steel tube is formed by splicing four parts, namely a first round-end shaped outer steel tube (7), a second round-end shaped outer steel tube (8), a third round-end shaped outer steel tube (9) and a fourth round-end shaped outer steel tube (10). The first round-end shaped outer steel tube (7), the second round-end shaped outer steel tube (8), the third round-end shaped outer steel tube (9) and the fourth round-end shaped outer steel tube (10) each occupy 1 / 4 of the round-end shaped outer steel tube. The four parts are welded to form an integral round-end shaped outer steel tube.

5. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 1 is characterized in that: The reinforcement ring (6) is arranged inside the round-end outer steel pipe, a single reinforcement ring (6) is in the shape of a round-end ring, and the outer side of the reinforcement ring (6) is welded to the inner side wall of the round-end outer steel pipe.

6. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 1 is characterized in that: The reinforcement ring (6) is composed of a left part and a right part, and the left and right parts are respectively welded to the radial reinforcement plate (5).

7. The reinforced node of the cross steel tube concrete column for cooling tower based on equal strength design according to claim 2 is characterized in that: The bottom cut surfaces of the first circular steel tube (1) and the second circular steel tube (2) are welded to the top surface of the reinforcement ring of the uppermost layer, and the top cut surfaces of the third circular steel tube (3) and the fourth circular steel tube (4) are welded to the bottom surface of the reinforcement ring (6) of the lowermost layer; the radial reinforcement plate (5) extends upward and downward respectively, extending above the reinforcement ring of the uppermost layer and below the reinforcement ring of the lowermost layer, and the side cut surfaces of the first circular steel tube (1), the second circular steel tube (2), the third circular steel tube (3) and the fourth circular steel tube (4) are respectively welded to the corresponding side surfaces of the radial reinforcement plate (5).

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