Rectangular steel pipe concrete structure
By setting first and second stiffening ribs inside the rectangular steel tube and tightly bonding them with concrete, the problems of local crushing and low load transfer efficiency of rectangular steel tube concrete members are solved, thereby improving the buckling resistance and stress performance.
Patent Information
- Application Number
- CN202423259016.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2034-12-27
AI Technical Summary
When rectangular steel tube concrete members are subjected to loads, there are problems such as local concrete crushing and low load transfer efficiency. Existing stiffening rib designs cannot effectively improve bending stiffness and bond strength, resulting in poor structural performance.
Multiple first stiffening ribs and second stiffening ribs are set inside the rectangular steel tube. The first stiffening ribs are arranged in a ring at intervals along the height direction, and the second stiffening ribs are arranged in a T-shape at intervals along the circumference. The web is connected to the wall of the rectangular steel tube and formed into an integral structure by welding. Concrete is then filled to ensure a tight bond between the steel tube and the concrete.
It significantly improves the buckling resistance and ductility of rectangular steel tube concrete structures, enhances load transfer efficiency, prevents buckling of the steel tube wall, and improves overall stress performance and seismic energy dissipation capacity.
Smart Images
Figure CN223647209U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of building structure technology, and in particular to a rectangular steel tube concrete structure. Background Technology
[0002] Currently, concrete-filled steel tube (CFST) members are favored due to their ease of construction. The steel tubes not only serve as the formwork for the concrete but also bear loads during construction, thus avoiding the adverse effects of concrete curing and significantly improving construction progress. CFST members are divided into rectangular and circular types, but because circular steel tubes are inferior to rectangular steel tubes in terms of bending stiffness, joint connections, and space utilization, rectangular CFST members are more commonly used in engineering projects.
[0003] However, rectangular steel-concrete composite members have certain limitations. Due to uneven confinement of the concrete, with stronger confinement at the corners and weaker confinement in the center, local crushing of the central concrete may occur, leading to local buckling of the steel tube before it reaches full-section yield. Furthermore, when a rectangular steel-concrete composite column is under load, most of the load acts directly on the steel tube; the bond force between the steel and concrete is insufficient to effectively transfer the load to the core concrete region. This results in low load transfer efficiency and poor structural performance.
[0004] In existing engineering practices, flat orthogonal stiffeners are typically installed inside steel tubes to mitigate local buckling. While these flat stiffeners can alleviate local buckling to some extent, their effect is limited and they do not increase the ductility of the steel tube after yielding. Furthermore, their effect on improving the bond strength between the steel tube and concrete is not significant, and their overall improvement on the load-bearing capacity of concrete-filled steel tube members is relatively small. Utility Model Content
[0005] The purpose of this invention is to provide a rectangular steel tube concrete structure that can improve load-bearing capacity.
[0006] To achieve the above objectives, this utility model provides a rectangular steel tube concrete structure, including a rectangular steel tube, a first stiffening rib, and a second stiffening rib. The first stiffening rib and the second stiffening rib are disposed inside the rectangular steel tube. A plurality of first stiffening ribs are spaced apart along the height direction of the rectangular steel tube, and a plurality of first stiffening ribs at the same height are connected to form a ring. A plurality of second stiffening ribs are spaced apart along the circumferential direction of the inner wall of the rectangular steel tube, and the cross-section of the second stiffening rib is T-shaped.
[0007] The rectangular steel tube, the first stiffening rib, and the second stiffening rib are filled with concrete to form a rectangular steel tube concrete structure.
[0008] Furthermore, the second stiffening rib includes a web and a flange disposed at one end of the web, the web being disposed in the middle of the flange, and the web being connected to the wall of the rectangular steel pipe.
[0009] Furthermore, the distance between adjacent second stiffening ribs or the distance between the second stiffening rib and the wall of the rectangular steel pipe is the setting spacing, and the setting spacing d s satisfy:
[0010]
[0011] Where t is the wall thickness of the rectangular steel pipe, f y The value is the yield strength of the steel in the rectangular steel pipe.
[0012] Furthermore, the cross-sectional area A of the second stiffening rib S The ratio of the area ratio to the cross-sectional area A1 of the rectangular steel pipe is the area ratio δ, and the area ratio δ satisfies:
[0013]
[0014] in, A1 = b * t, where b is the width of the rectangular steel pipe wall and t is the thickness of the rectangular steel pipe wall.
[0015] Furthermore, the height h of the web plate s The distance between the flange and the pipe wall is given by h, and the height of the web is given by h. s Must meet:
[0016] A s =(h s +b s )t s
[0017] Among them, A s The cross-sectional area A of the second stiffening rib S b s h is the flange width of the airfoil. s / b s The value range of t is 1 to 2. s The thickness of the web plate;
[0018] The minimum value of γ′ of the stiffness ratio of the second stiffening rib to the concrete and the rectangular steel pipe wall. min Must meet:
[0019]
[0020] Among them, f ydenoted as , where b is the yield strength of the steel in the rectangular steel pipe, t is the width of the pipe wall, δ is the thickness of the pipe wall, and δ is the area ratio.
[0021] Furthermore, the distance d between adjacent first stiffening ribs hs 0.8d s ~1.5d s .
[0022] Furthermore, the width h of the first stiffening rib hs 0.7h s ~0.9h s The thickness t of the first stiffening rib hs For t s .
[0023] Furthermore, the rectangular steel pipe is connected to the first stiffening rib and the second stiffening rib by concrete to form an integral structure.
[0024] Furthermore, the first stiffening rib and the second stiffening rib are connected to the rectangular steel pipe by welding.
[0025] Furthermore, the longitudinal height of the second stiffening rib is the same as the longitudinal height of the rectangular steel tube.
[0026] Compared with existing technologies, the rectangular steel-concrete composite structure of this invention has the following advantages: Several second stiffening ribs are arranged in the longitudinal direction of the rectangular steel tube, and a series of first stiffening ribs are set in the horizontal direction, so that the first stiffening ribs on the same horizontal plane form a continuous ring structure. This significantly increases the buckling resistance of the steel-concrete composite tube wall, prevents buckling of the steel tube wall, and ensures the effectiveness of the tube wall throughout the entire cross-section. The second stiffening ribs adopt a T-shaped section, and their web and flanges help to bond more tightly with the concrete, thereby improving the synergistic stress performance of the steel tube and concrete and enhancing the force transmission efficiency. The combined effect of the first and second stiffening ribs helps to improve the ductility of the steel-concrete composite tube and enhance its seismic energy dissipation capacity. Attached Figure Description
[0027] Figure 1 This is a top view of the rectangular steel tube concrete structure according to an embodiment of this utility model;
[0028] Figure 2 This is an enlarged structural schematic diagram of point a in an embodiment of this utility model;
[0029] Figure 3 This is a structural schematic diagram showing the dimensions of the first and second stiffening ribs in an embodiment of this utility model;
[0030] Figure 4This is a schematic diagram of the structure of the first and second stiffening ribs disposed on the rectangular steel tube according to an embodiment of the present invention;
[0031] Figure 5 This is a structural schematic diagram of the second stiffening rib, the combined section of concrete and rectangular steel pipe according to an embodiment of this utility model;
[0032] In the figure, 1 is a rectangular steel pipe; 2 is the first stiffening rib; 3 is the second stiffening rib; 31 is the web plate; 32 is the flange plate; and 4 is concrete. Detailed Implementation
[0033] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.
[0034] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and 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, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.
[0035] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" 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, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0036] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0037] In the embodiments of the application, "parallel" refers to a state in which the angle formed by two lines, a line and a surface, or a surface is -1° to 1°. "Perpendicular" refers to a state in which the angle formed by two lines, a line and a surface, or a surface is 89° to 91°. Equal distances, equal angles, or equal areas refer to a state in which the tolerance range is -1% to 1%.
[0038] like Figures 1-5 As shown, this utility model provides a rectangular steel tube concrete structure, including a rectangular steel tube 1, a plurality of first stiffening ribs 2, a plurality of second stiffening ribs 3 and concrete 4, wherein the first stiffening ribs 2 and the second stiffening ribs 3 are disposed inside the rectangular steel tube.
[0039] Specifically, the column body of the rectangular steel pipe 1 is formed by welding four steel plates together. The column body of the rectangular steel pipe 1 has a cavity inside. The first stiffening rib 2 and the second stiffening rib 3 are welded to the inner side of the pipe wall of the rectangular steel pipe 1. The internal cavity of the rectangular steel pipe 1 can be filled with concrete 4.
[0040] Specifically, multiple first stiffening ribs 2 are spaced apart along the height direction of the rectangular steel pipe 1, and multiple first stiffening ribs 2 at the same height are connected to form a ring. That is, a rectangular steel pipe concrete structure can be provided with multiple layers of inner ring stiffening ribs composed of first stiffening ribs 2 connected end to end.
[0041] This utility model is provided with a series of first stiffening ribs 2, so that the first stiffening ribs 2 on the same horizontal plane are connected to form a continuous ring structure. This can significantly increase the buckling bearing capacity of the steel-concrete composite pipe wall, avoid buckling of the steel pipe wall, and ensure the effectiveness of the pipe wall throughout the entire cross section.
[0042] Multiple second stiffening ribs 3 are spaced apart along the inner wall of the rectangular steel pipe 1, and the cross-section of the second stiffening ribs is T-shaped; the rectangular steel pipe 1 and the first stiffening rib 2 and the second stiffening rib 3 are filled with concrete to form a rectangular steel pipe concrete structure.
[0043] Specifically, the second stiffening rib 3 is T-shaped and is arranged circumferentially along the rectangular steel pipe 1. The longitudinal height of the second stiffening rib 3 is the same as the longitudinal height of the rectangular steel pipe 1. The second stiffening rib 3 includes a web 31 and a flange 32 disposed at one end of the web 31. The web 31 is disposed in the middle of the flange 32, and the web 31 is connected to the pipe wall of the rectangular steel pipe 1. Preferably, the second stiffening rib 3 can be formed by cutting the web of an I-beam along its centerline or by splicing two steel plates together.
[0044] Optionally, the first stiffening rib 2 and the second stiffening rib 3 can be made of steel, aluminum alloy, etc. Preferably, the first stiffening rib 2 and the second stiffening rib 3 are made of Q235B steel.
[0045] The second stiffening rib 3 in this embodiment of the present invention has a T-shaped cross section. Its web and flange help to bond more tightly with the concrete 4, thereby improving the joint stress performance of the steel pipe and the concrete 4 and enhancing the force transmission efficiency.
[0046] The combined effect of the first stiffening rib 2 and the second stiffening rib 3 in this embodiment of the invention helps to improve the ductility of the steel-concrete composite 4 and enhance its seismic energy dissipation capacity.
[0047] See Figure 3 and Figure 4 As shown, in one optional embodiment of this utility model, the long side dimension of the rectangular steel pipe 1 is b, the thickness of the steel plate on the pipe wall of the rectangular steel pipe 1 is t, and the yield strength of the steel used is f. y It is sufficient to satisfy the following formula.
[0048] One or more second stiffening ribs 3 are evenly spaced on the pipe wall, and the distance between two adjacent second stiffening ribs 3 or the distance between the second stiffening rib 3 and the pipe wall of the rectangular steel pipe 1 is the spacing d. s The setting of the spacing d s satisfy:
[0049]
[0050] Where t is the wall thickness of the rectangular steel pipe 1, and f y The value is the yield strength of the steel in the rectangular steel pipe 1.
[0051] In one optional embodiment of this utility model, the cross-sectional area A of the second stiffening rib 3 is... S The ratio of the area ratio to the cross section A1 of the rectangular steel pipe 1 is the area ratio δ, and the area ratio δ satisfies:
[0052]
[0053] in, A1 = b * t, where b is the width of the rectangular steel pipe 1 and t is the thickness of the rectangular steel pipe 1.
[0054] Furthermore, the height h of the web 31 s The distance between the flange 32 and the pipe wall is given, and the height h of the web 31 is given. s Must meet:
[0055] A s =(h s +b s )t s
[0056] Among them, A s The cross-sectional area A of the second stiffening rib 3 S b s h is the flange width of the wingplate 32. s / b s The value range of t is 1 to 2. s The thickness of the web 31;
[0057] Specifically, t s The width-to-thickness ratio limit for T-section S4 grade is taken according to the "Steel Structure Design Standard" (GB 50017-2017); and the width-to-thickness ratio of the flange extensions of web 31 and flange 32 is 1.5 times the width-to-thickness ratio limit for T-section S4 grade in the "Steel Structure Design Standard" (GB 50017-2017).
[0058] See Figure 5 The combined section shown represents the bending stiffness EI of the rectangular steel pipe 1. eq The calculation formula is:
[0059] EI eq =E s I s +E c I c ,
[0060] Among them, E s I is the elastic modulus of the second stiffening rib 3. s E is the moment of inertia of the second stiffening rib 3. c for Figure 5 The elastic modulus of the concrete 4 in the part that works together with the second stiffening rib 3, I c for Figure 5 The moment of inertia of the concrete 4 that works together with the second stiffening rib 3.
[0061] Then, the stiffness ratio γ′ of the combined section closed by the second stiffening rib 3, concrete 4, and rectangular steel pipe 1 is calculated, and its calculation formula is:
[0062]
[0063] Among them, EI eq Let be the bending stiffness of the rectangular steel pipe 1, D be the bending stiffness per unit width of the plate, and b be the width of the rectangular steel pipe 1 wall.
[0064] The lower limit of the composite section stiffness ratio γ′ is γ min The stiffness ratio γ of the combination of the second stiffening rib 3 and the concrete 4 min Must meet:
[0065]
[0066]
[0067] Among them, f y denoted as , b is the yield strength of the steel in the rectangular steel pipe 1, b is the width of the pipe wall in the rectangular steel pipe 1, t is the thickness of the pipe wall in the rectangular steel pipe 1, and δ is the area ratio.
[0068] In this embodiment of the invention, the distance d between adjacent first stiffening ribs 2 hs 0.8d s ~1.5d s The smaller the distance between two adjacent first stiffening ribs 2, that is, the denser the first stiffening ribs 2 are arranged, the greater their load-bearing capacity and the greater the rate of increase in load-bearing capacity.
[0069] In this embodiment of the invention, the width h of the first stiffening rib 2 is... hs 0.7h s ~0.9h s The thickness t of the first stiffening rib 2 hs For t s .
[0070] See Figure 1 , Figure 2 and Figure 4 As shown, the rectangular steel pipe 1 is connected to the first stiffening rib 2 and the second stiffening rib 3 by concrete 4 to form an integral structure. The first stiffening rib 2 and the second stiffening rib 3 are connected to the rectangular steel pipe 1 by welding.
[0071] The working process of this utility model is as follows: the first stiffening rib 2 and the second stiffening rib 3 are first welded together to form a whole. The second stiffening rib 3 is continuous. The first stiffening rib 2 is cut off by the second stiffening rib 3. The second stiffening rib 3 and the first stiffening rib 2 are both connected to the inner wall of the rectangular steel pipe 1 by butt welding.
[0072] In summary, this utility model embodiment provides a rectangular steel-concrete composite structure. By providing multiple second stiffening ribs in the vertical direction and multiple first stiffening ribs in the horizontal direction of the rectangular steel tube, and connecting the first stiffening ribs in a ring on a horizontal plane, the buckling bearing capacity of the steel-concrete composite tube wall can be significantly improved, preventing buckling of the rectangular steel tube wall and ensuring the entire tube wall meets the full cross-sectional effectiveness requirement. The second stiffening ribs have a T-shaped cross-section, and their longitudinal stiffening ribs can better bond with the concrete, enhancing the overall stress performance of the steel tube and concrete and improving force transmission efficiency. The combination of the first and second stiffening ribs can improve the ductility of the steel-concrete composite tube, giving it better energy dissipation capacity.
[0073] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.
Claims
1. A rectangular steel-tube concrete structure, characterized in that, It includes a rectangular steel pipe, a first stiffening rib, and a second stiffening rib, which are disposed inside the rectangular steel pipe; a plurality of first stiffening ribs are spaced apart along the height direction of the rectangular steel pipe, and a plurality of first stiffening ribs at the same height are connected to form a ring; a plurality of second stiffening ribs are spaced apart along the circumferential direction of the inner wall of the rectangular steel pipe, and the cross-section of the second stiffening rib is T-shaped; The rectangular steel tube, the first stiffening rib, and the second stiffening rib are filled with concrete to form a rectangular steel tube concrete structure.
2. The rectangular steel tube concrete structure according to claim 1, characterized in that, The second stiffening rib includes a web and a flange disposed at one end of the web. The web is disposed in the middle of the flange and is connected to the wall of the rectangular steel pipe.
3. The rectangular steel tube concrete structure according to claim 2, characterized in that, The distance between adjacent second stiffening ribs or the distance between the second stiffening rib and the wall of the rectangular steel pipe is the setting spacing, and the setting spacing d s satisfy: Where t is the wall thickness of the rectangular steel pipe, f y The value is the yield strength of the steel in the rectangular steel pipe.
4. The rectangular steel tube concrete structure according to claim 3, characterized in that, The cross-sectional area A of the second stiffening rib S The ratio of the area ratio to the cross-sectional area A1 of the rectangular steel pipe is the area ratio δ, and the area ratio δ satisfies: in, A1 = b * t, where b is the width of the rectangular steel pipe wall and t is the thickness of the rectangular steel pipe wall.
5. The rectangular steel tube concrete structure according to claim 4, characterized in that, The height h of the web s The distance between the flange and the pipe wall is given by h, and the height of the web is given by h. s Must meet: A s =(h s +b s )t s Among them, A s The cross-sectional area A of the second stiffening rib S b s h is the flange width of the airfoil. s / b s The value range of t is 1 to 2. s The thickness of the web plate; The minimum value of γ′ of the stiffness ratio of the second stiffening rib to the concrete and the rectangular steel pipe wall. min Must meet: Among them, f y denoted as , where b is the yield strength of the steel in the rectangular steel pipe, t is the width of the pipe wall, δ is the thickness of the pipe wall, and δ is the area ratio.
6. The rectangular steel tube concrete structure according to claim 5, characterized in that, The distance d between adjacent first stiffening ribs hs 0.8d s ~1.5d s .
7. The rectangular steel tube concrete structure according to claim 5, characterized in that, The width h of the first stiffening rib hs 0.7h s ~0.9h s The thickness t of the first stiffening rib hs For t s .
8. The rectangular steel tube concrete structure according to claim 1, characterized in that, The rectangular steel pipe is connected to the first stiffening rib and the second stiffening rib by concrete to form an integral structure.
9. The rectangular steel-tube concrete structure according to any one of claims 1 to 8, characterized in that, The first stiffening rib and the second stiffening rib are connected to the rectangular steel pipe by welding.
10. The rectangular steel tube concrete structure according to claim 1, characterized in that, The longitudinal height of the second stiffening rib is the same as the longitudinal height of the rectangular steel pipe.