Natural ventilation cooling tower and rectangular concrete filled steel tube cross strut thereof

Abstract

The invention discloses a rectangular concrete-filled steel tube cross strut of a natural ventilation cooling tower, which comprises four rectangular steel tube limb columns and cross nodes, and the end parts of the rectangular steel tube limb columns are on the same plane and are connected with the cross nodes to form a cross structure; the cross joint comprises a joint top plate, a joint bottom plate, a plurality of joint plates, an inner ring plate, an inner stiffening plate and an outer stiffening plate, the joint plates, the joint top plate, the joint bottom plate and the four rectangular steel pipe limb columns form a closed space, and open holes are formed in the joint top plate, the joint bottom plate and the inner ring plate and used for concrete pouring and circulation. The inner stiffening plate is arranged between the node top plate and the node bottom plate and is connected with a part of the node plates; the external stiffening plate is arranged at the middle waist line of the other part of gusset plates; the inner ring plate, the joint top plate and the joint bottom plate are arranged in the closed space in parallel and perpendicularly intersect with the inner stiffening plate. The four rectangular steel pipe limb columns are arranged at the holes of the joint top plate and the joint bottom plate. The manufacturing cost can be saved.

Description

Technical Field

[0001] This application relates to the field of industrial cooling design technology, and in particular to a natural ventilation cooling tower and its rectangular steel tube concrete cross support. Background Technology

[0002] There are currently four main structural forms for the support systems of natural draft cooling towers: reinforced concrete structures, steel-concrete composite structures, steel structures, and steel-concrete composite structures. Reinforced concrete supports are the most widely used in natural draft cooling towers, while steel structure supports and steel-concrete composite supports have only been used in natural draft cooling towers in recent years.

[0003] Regarding the cross-sectional shape of the columns, the main cross-sectional shapes of reinforced concrete columns are circular, rectangular and polygonal, steel structure columns mainly adopt lattice type columns, and steel-concrete composite columns mainly adopt circular cross-sections.

[0004] The following problems exist with the four structural types of natural draft cooling tower support systems:

[0005] Problems and defects of reinforced concrete columns: 1. Construction requires a large amount of scaffolding for formwork; 2. Long construction period; 3. Large initial geometric defects, and the column axis deviates from the design axis after construction; 4. Large column cross-sectional dimensions, which increases the thickness of the lower ring beam at the contact point between the column and the tower, thus increasing the total amount of concrete and steel reinforcement used in the cooling tower structure.

[0006] Problems and defects of steel-concrete composite columns: 1. Construction requires the erection of a large amount of scaffolding for formwork; 2. Long construction period. Compared with reinforced concrete columns, although the column cross-sectional size is reduced, construction still requires the erection of a large amount of scaffolding.

[0007] Problems and defects of steel structure lattice columns: 1. Large steel consumption and high cost; 2. High corrosion protection cost; 3. Large column cross-sectional dimensions, increasing the footprint.

[0008] Problems and defects of circular steel tube concrete columns: 1. Waste of materials: Because the bending resistance of a circular cross section is the same in and out of the X-shaped intersection plane, while the calculated length of an X-shaped column differs by nearly double in and out of the plane, there is a waste of materials in the plane of the circular cross section.

[0009] Problems and defects of cross-pipe joints: 1. Waste of steel; 2. Limited operating space at the intersection of left and right pipes, making welding difficult and easily leading to substandard weld quality. Summary of the Invention

[0010] To address the aforementioned problems, this invention provides a rectangular steel tube concrete cross support for a natural ventilation cooling tower, comprising four rectangular steel tube columns and a cross node. The ends of each rectangular steel tube column are on the same plane and connected to the cross node to form a cross structure. The cross node includes a node top plate, a node bottom plate, several node plates, an inner ring plate, an inner stiffening plate, and an outer stiffening plate. The node plates, node top plate, node bottom plate, and four rectangular steel tube columns constitute a closed space. The node top plate, node bottom plate, and inner ring plate have openings for concrete pouring and flow. The inner stiffening plate is located between the node top plate and node bottom plate and connects to a portion of the node plates. The outer stiffening plate is located at the middle waistline of another portion of the node plates. The inner ring plate is arranged parallel to the node top plate and node bottom plate within the closed space and intersects the inner stiffening plate perpendicularly. The four rectangular steel tube columns are located at the openings in the node top plate and node bottom plate.

[0011] A further technical solution of the present invention is: there is a distance 'a' at the intersection of adjacent rectangular steel pipe columns to provide operating space for welding.

[0012] A further technical solution of the present invention is: four node plates, node top plate, node bottom plate and four rectangular steel pipe columns form a closed space, the inner stiffening plate passes through the inner ring plate and separates the two openings of the inner ring plate, and the inner stiffening plate is in contact with the oppositely arranged first node plate and second node plate; the outer stiffening plate is arranged at the waistline of the oppositely arranged third node plate and fourth node plate.

[0013] A further technical solution of the present invention is: three inner ring plates are provided, and an inner stiffening plate passes through the three inner ring plates in sequence and separates the two openings of the inner ring plates.

[0014] A further technical solution of the present invention is to replace the four rectangular steel pipe columns with four circular steel pipe columns.

[0015] In another aspect, the present invention provides a welding method for the above-mentioned rectangular steel tube concrete cross support, wherein the various structures are connected by full penetration welds.

[0016] A further technical solution of the present invention is: the welding step specifically includes:

[0017] Step 1: Weld the node top plate, inner stiffening plate, inner ring plate and node bottom plate into a whole to form the node skeleton;

[0018] Step 2: Connect the node plate to the node frame using a sectioned full penetration weld;

[0019] Step 3: Connect the external stiffening plate to the corresponding node plate using a sectioned full penetration weld;

[0020] Step 4: Weld the steel pipes of the four limbs to the top plate and bottom plate of the node, respectively.

[0021] A third aspect of the present invention provides a natural draft cooling tower, comprising:

[0022] The cooling tower ring base has a circular ring structure.

[0023] Rectangular steel-concrete composite cross pillars, which adopt the above-mentioned rectangular steel-concrete composite cross pillars;

[0024] Multiple rectangular steel-concrete intersecting supports are sequentially arranged in a ring on the cooling tower's ring base;

[0025] The tower is mounted on multiple rectangular steel-concrete intersecting supports.

[0026] A further technical solution of the present invention is: by adjusting the cross-sectional dimensions of the rectangular steel tube columns, the in-plane slenderness ratio of the cross-support is increased. equal to the out-of-plane slenderness ratio To reduce material waste, adjacent columns are given an in-plane constraint due to their intersection, where l1 and l2 represent the in-plane and out-of-plane computational lengths, respectively. x and I y These refer to the moment of inertia of the cross section about the x-axis and the moment of inertia of the cross section about the y-axis, respectively, and A represents the cross-sectional area.

[0027] A further technical solution of the present invention is to replace the rectangular steel tube concrete cross column with a single cross node with a rectangular steel tube concrete cross column having multiple cross nodes.

[0028] This invention provides a rectangular steel tube concrete cross support for a natural ventilation cooling tower. The steel tube serves as a formwork for the concrete, improving construction speed and quality. By reducing the cross-sectional area of ​​the support, the floor space occupied by the cooling tower structure is saved. The reduction in the cross-sectional size of the support can reduce the thickness of the lower ring beam of the tower, thereby saving the amount of tower concrete and steel reinforcement and reducing construction costs.

[0029] The advantages of this invention compared to circular steel-concrete composite columns are as follows: Based on the characteristic that the in-plane calculated length of the intersecting structure is less than the out-of-plane calculated length, a rectangular cross-section is proposed to replace the circular cross-section, with the long side of the rectangular cross-section arranged along the out-of-plane direction and the short side arranged along the in-plane direction. This solves the material waste caused by the excess in-plane bearing capacity of the circular cross-section.

[0030] The cross joint proposed in this invention reduces the number of steel pipe cuts and the generation of steel pipe waste, thus saving manufacturing costs. By increasing the distance between adjacent columns, not only can the weld quality be improved by increasing the welding operation space, but the load-bearing capacity of the joint can also be avoided due to the concentration of multiple welds. Most of the reinforcing members of the joint of this invention are arranged inside the joint, which also has the advantage of aesthetic appearance. Attached Figure Description

[0031] Figure 1 This is a disassembled view of the overall structure of the rectangular steel tube concrete cross support column of the natural ventilation cooling tower according to an embodiment of the present invention;

[0032] Figure 2 This is a front view of the rectangular steel tube concrete intersecting support of the natural ventilation cooling tower according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the natural draft cooling tower structure according to an embodiment of the present invention.

[0034] Figure 4 (a) is a schematic diagram of the instability of the rectangular steel tube concrete cross support of the natural ventilation cooling tower according to an embodiment of the present invention. Figure 4 (b) is a circular cross-sectional view of a rectangular steel-concrete composite cross support. Figure 4 (c) is a rectangular cross-section diagram of a rectangular steel-concrete composite cross support. Detailed Implementation

[0035] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] In the description of this invention, 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," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0037] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0041] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] An embodiment of the present invention provides a rectangular steel-concrete cross-support for a natural ventilation cooling tower, such as... Figure 1 As shown, it includes four rectangular steel pipe columns (rectangular steel pipe column 15 on the top plate of the node and rectangular steel pipe column 19 on the bottom plate of the node) and intersecting nodes. The ends of each rectangular steel pipe column are on the same plane and are connected to the intersecting nodes to form an intersecting structure; the intersecting nodes include a node top plate 21, a node bottom plate 18, and several node plates ( Figure 1 The node plate 16 and node plate 23 shown), inner ring plate ( Figure 1The inner ring plate 24, inner ring plate 25, inner stiffening plate 26, inner stiffening plate 22, and outer stiffening plate 17 are shown. The node plate, node top plate 21, node bottom plate 18, and four rectangular steel pipe columns form a closed space. The node top plate 21, node bottom plate 18, and inner ring plates (24, 25, 26) are provided with openings for concrete pouring and flow. The inner stiffening plate 22 is located between the node top plate 21 and node bottom plate 18 and is connected to a part of the node plate. The outer stiffening plate 17 is located at the middle waistline of another part of the node plate. The inner ring plates (24, 25, 26) are arranged parallel to the node top plate 21 and node bottom plate 18 in the closed space and perpendicular to the inner stiffening plate 22. The four rectangular steel pipe columns are located at the openings of the node top plate 21 and node bottom plate 18.

[0043] like Figure 2 As shown, there is a distance 'a' between adjacent rectangular steel pipe columns at the intersection node to provide operating space for welding.

[0044] like Figure 1 As shown, four node plates ( Figure 1 Only node plates 16 and 23 are marked, along with node top plate 21, node bottom plate 18, and four rectangular steel pipe columns. Figure 1 Only the rectangular steel pipe limbs 15 of the node top plate and the rectangular steel pipe limbs 19 of the node bottom plate are marked to form a closed space. The inner stiffening plate 22 passes through the inner ring plate (24, 25, 26) and separates the two openings of the inner ring plate (24, 25, 26). The inner stiffening plate 22 is in contact with the first node plate and the second node plate that are arranged opposite to each other. The outer stiffening plate 17 is set at the waistline of the third node plate and the fourth node plate that are arranged opposite to each other.

[0045] like Figure 1 As shown, three inner ring plates (24, 25, 26) are set, and the inner stiffening plate passes through the three inner ring plates in sequence and separates the two openings of the inner ring plates.

[0046] In some embodiments, four circular steel pipe columns can be used instead of four rectangular steel pipe columns.

[0047] Specifically, the joints of rectangular steel-concrete composite cross supports are as follows: Figure 1 , 2 As shown, the X-shaped support consists of a node and four limbs (upper left limb, upper right limb, lower left limb, and lower right limb). The steel pipes of the four limbs only require one horizontal cut, eliminating material waste. Adjacent limbs have a distance 'a' at the intersection node; this distance not only provides operational space for welding and improves welding quality but also prevents a decrease in load-bearing capacity due to the concentration of multiple welds. This intersection node is not limited to rectangular steel pipes but can also be used for circular steel pipes.

[0048] The internal structure of the cross node is as follows Figure 1The intersection joint consists of a node plate, top plate, bottom plate, inner ring plate, inner stiffening plate, and outer stiffening plate, all connected by full penetration welds. The node plate, top plate, bottom plate, and four columns form a closed space. Openings in the top plate, bottom plate, and inner ring plate facilitate concrete pouring and flow. The inner stiffening plate not only increases the joint's load-bearing capacity by increasing the steel content at the joint section but also enhances the joint's load-bearing capacity by preventing buckling of the node plate and increasing the confinement effect of the concrete. Similarly, the outer stiffening plate also increases the load-bearing capacity at the minimum cross-section of the joint (the section containing the inner ring plate) by increasing the steel content and preventing buckling of the node plate.

[0049] Another embodiment of the present invention is a welding method for the aforementioned rectangular steel tube concrete cross support, wherein the various structures are connected by full penetration welds. The welding steps specifically include:

[0050] Step 1: Weld the node top plate, inner stiffening plate, inner ring plate and node bottom plate into a whole to form the node skeleton;

[0051] Step 2: Connect the node plate to the node frame using a sectioned full penetration weld;

[0052] Step 3: Connect the external stiffening plate to the corresponding node plate using a sectioned full penetration weld;

[0053] Step 4: Weld the steel pipes of the four limbs to the top plate and bottom plate of the node, respectively.

[0054] Another embodiment of the present invention is a natural draft cooling tower, such as... Figure 3 As shown, it includes:

[0055] Cooling tower ring base 4, which is a circular ring structure;

[0056] Rectangular concrete cross support 2, which adopts the above-mentioned rectangular steel tube concrete cross support;

[0057] Multiple rectangular steel pipe concrete cross supports 2 are arranged in a ring on the cooling tower ring base 4; the cooling tower ring base 4 is provided with supports 3 for fixing the column limbs 19 of the rectangular concrete cross supports 2.

[0058] And the tower 1, which is set on multiple rectangular steel tube concrete intersecting supports 2.

[0059] Specifically, such as Figure 3As shown, the rectangular concrete-filled steel tube cross strut system is formed by circumferentially arraying single cross struts around the central axis of a natural draft cooling tower. The four corner points of a single X-shaped cross strut are on the same plane. The long sides of the rectangular cross section of the strut are arranged along the normal direction of the plane (pointing to the central axis of the natural draft cooling tower), and the short sides of the rectangular cross section are arranged within the plane. In addition, the rectangular concrete-filled steel tube cross strut system is not limited to a single cross strut system, but can also be used in a double cross strut system and a multi-cross strut system.

[0060] As Figure 4 shown, by adjusting the cross-sectional dimensions of the rectangular steel tube struts, the in-plane slenderness ratio of the cross strut is made equal to the out-of-plane slenderness ratio to reduce material waste. The adjacent struts give each other an in-plane restraint due to the crossing, where l1 and l2 respectively represent the in-plane calculated length and the out-of-plane calculated length, I x and I y respectively refer to the moment of inertia of the cross section about the x-axis and the moment of inertia of the cross section about the y-axis, and A represents the cross-sectional area.

[0061] Specifically, as Figure 4 can be seen, the adjacent struts give each other an in-plane restraint due to the crossing, resulting in the in-plane calculated length l1 being less than the out-of-plane calculated length l2. For a circular cross section, since the in-plane flexural rigidity is equal to the out-of-plane flexural rigidity (EIx = EIy), there is an excess in its in-plane bearing capacity, which further causes material waste. When using the Figure 3 rectangular cross strut shown ([[]] Figure 3 in which 5 represents the plane of the rectangular concrete-filled steel tube cross strut), the in-plane flexural rigidity of the rectangular cross section is less than the out-of-plane flexural rigidity (EIx < EIy). Therefore, the in-plane slenderness ratio of the cross strut can be made equal to the out-of-plane slenderness ratio by adjusting the height-width ratio (h / w) of the rectangular cross section, thereby reducing material waste and achieving an equal-strength design for the in-plane and out-of-plane bearing of the cross strut.

[0062] In other embodiments, rectangular concrete-filled steel tube cross struts with multiple cross nodes are used to replace the rectangular concrete-filled steel tube cross struts with a single cross node.

[0063] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity in description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as falling within the scope described in this specification.

[0064] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A rectangular steel-concrete composite cross support, characterized in that, The structure includes four rectangular steel pipe columns and intersecting nodes. The ends of each rectangular steel pipe column are connected to the intersecting nodes on the same plane to form an intersecting structure. Each intersecting node includes a node top plate, a node bottom plate, several node plates, an inner ring plate, an inner stiffening plate, and an outer stiffening plate. The node plates, node top plate, node bottom plate, and four rectangular steel pipe columns form a closed space. The node top plate, node bottom plate, and inner ring plate have openings for concrete pouring and flow. The inner stiffening plate is located between the node top plate and node bottom plate and is connected to a portion of the node plates. The outer stiffening plate is located at the middle waistline of another portion of the node plates. The inner ring plate is arranged parallel to the node top plate and node bottom plate within the closed space and intersects the inner stiffening plate perpendicularly. Four rectangular steel pipe columns are installed at the openings in the top and bottom plates of the node.

2. The rectangular steel-concrete composite cross support according to claim 1, characterized in that, There is a distance 'a' between adjacent rectangular steel pipe columns at the intersection node to provide operating space for welding.

3. The rectangular steel-concrete composite cross support according to claim 1, characterized in that, The four node plates, together with the node top plate, node bottom plate, and four rectangular steel pipe columns, form a closed space. The inner stiffening plate passes through the inner ring plate and separates the two openings of the inner ring plate. The inner stiffening plate is in contact with the first and second node plates that are arranged opposite to each other. The outer stiffening plate is set at the waistline of the third and fourth node plates that are arranged opposite to each other.

4. The rectangular steel-concrete composite cross support according to claim 1, characterized in that, Three inner ring plates are set, and the inner stiffening plate passes through the three inner ring plates in sequence and separates the two openings of the inner ring plates.

5. The rectangular steel-concrete composite cross support according to claim 1, characterized in that, Replace the four rectangular steel pipe columns with four circular steel pipe columns.

6. A welding method for a rectangular steel tube concrete cross support as described in claim 1, characterized in that, The various structures are connected by full penetration welds.

7. The welding method according to claim 6, characterized in that, The welding steps specifically include: Step 1: Weld the node top plate, inner stiffening plate, inner ring plate and node bottom plate into a whole to form the node skeleton; Step 2: Connect the gusset plate to the gusset frame using a sectioned full penetration weld; Step 3: Connect the external stiffening plate to the corresponding node plate using a sectioned full penetration weld; Step 4: Weld the steel pipes of the four limbs to the top plate and bottom plate of the node, respectively.

8. A natural draft cooling tower, characterized in that, include: The cooling tower ring base has a circular ring structure. A rectangular steel-concrete composite cross support, wherein the rectangular steel-concrete composite cross support is as described in any one of claims 1 to 7; Multiple rectangular steel-concrete intersecting supports are sequentially arranged in a ring on the cooling tower's ring base; The tower is mounted on multiple rectangular steel-concrete intersecting supports.

9. The natural draft cooling tower according to claim 8, characterized in that, The in-plane slenderness ratio of the cross-bracing is adjusted by modifying the cross-sectional dimensions of the rectangular steel tube columns. equal to the out-of-plane slenderness ratio To reduce material waste, adjacent columns are given an in-plane constraint due to their intersection, where l1 and l2 represent the in-plane and out-of-plane computational lengths, respectively. x and I y These refer to the moment of inertia of the cross section about the x-axis and the moment of inertia of the cross section about the y-axis, respectively, and A represents the cross-sectional area.

10. The natural draft cooling tower according to claim 8, characterized in that, Replace rectangular steel tube concrete cross struts with a single cross node with rectangular steel tube concrete cross struts that have multiple cross nodes.

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