A cable tower steel anchor beam structure and a design method

Abstract

This application relates to a steel anchor beam structure and design method for a cable tower. The steel anchor beam structure includes a tower column, an anchor beam, and cross braces. The tower column has a cavity. The anchor beam is installed in the cavity along the longitudinal direction of the bridge and is fixedly connected to the two inner side walls of the tower column. Brackets are provided at both ends of the anchor beam, fixed to the bottom of the anchor beam and fixed to the tower column. Cross braces are fixed on both sides of the anchor beam along the transverse direction of the bridge and fixedly connected to the other two inner side walls of the tower column. By setting cross braces on both sides of the anchor beam along the transverse direction of the bridge, support force is provided for the bottom plate of the upper cross beam inside the tower column, reducing the calculated span of the tower wall in the longitudinal direction of the bridge, reducing the local bending moment effect of the tower wall in the longitudinal direction of the bridge caused by the axial force of the bottom plate of the upper cross beam, ensuring that the local stress of the tower wall meets the requirements, and solving the technical problem in related technologies where it is impossible to set transverse diaphragms inside the tower column in the cable anchor area, resulting in the tower wall in the longitudinal direction of the bridge being unable to withstand the axial force of the bottom plate of the upper cross beam in the box section, and thus failing to provide a complete maintenance passage.

Description

Technical Field

[0001] This application relates to the field of bridge construction, specifically to a cable tower steel anchor beam structure and its design method. Background Technology

[0002] Currently, steel anchor beams for cable-stayed bridge towers have the characteristics of clear stress distribution, simple structure, and convenient processing. They are widely used in long-span cable-stayed bridges and cable-stayed-suspension bridge systems. For portal-type or H-type bridge towers, the upper crossbeam is usually set in the tower column anchorage zone to enhance the overall stiffness and stability of the bridge tower.

[0003] In related technologies, the lower edge of the upper crossbeam is located inside the tower column and a steel anchor beam is installed. It is impossible to install a transverse diaphragm inside the tower column, which means that the longitudinal bridge wall of the tower column cannot withstand the axial force of the bottom plate of the box-section upper crossbeam. Therefore, the upper crossbeam cannot be a box-section beam, but can only be a π-section beam without a bottom plate or a vertical plate-type crossbeam without a top or bottom plate. This cannot provide a complete maintenance passage and increases the safety risks for maintenance personnel.

[0004] Therefore, it is necessary to design a new steel anchor beam structure for cable towers to overcome the above problems. Summary of the Invention

[0005] This application provides a steel anchor beam structure and design method for cable towers, which can solve the technical problem in related technologies where transverse diaphragms cannot be installed inside the tower column in the cable anchor zone, resulting in the tower column's longitudinal bridge wall being unable to withstand the axial force of the bottom plate of the box-section upper crossbeam. Consequently, the bridge tower cannot be equipped with a box-section upper crossbeam, cannot provide a complete maintenance passage, and increases the safety risks for maintenance personnel.

[0006] In a first aspect, embodiments of this application provide a cable tower steel anchor beam structure, comprising: a tower column, an anchor beam, and a cross brace. The tower column has a cavity; the anchor beam is installed in the cavity along the longitudinal direction of the bridge and is fixedly connected to the two inner side walls of the tower column; the anchor beam has brackets at both ends, the brackets are fixed to the bottom of the anchor beam, and the brackets are fixed to the tower column; the cross brace is fixed to both sides of the anchor beam along the transverse direction of the bridge and is fixedly connected to the other two inner side walls of the tower column.

[0007] In conjunction with the first aspect, in one embodiment, the cross brace is connected to a support assembly, the support assembly being fixed to the tower column via a first pre-embedded assembly. The first pre-embedded assembly includes a first pre-embedded plate, a plurality of first shear keys, and a first perforated plate connector that are interconnected. The first pre-embedded plate is pre-embedded in the tower column and is fixed to the support assembly. The plurality of first shear keys and the first perforated plate connectors are pre-embedded in the tower column and are fixed to the first pre-embedded plate.

[0008] In conjunction with the first aspect, in one embodiment, the cross brace is bolted to the support assembly via a splicing plate.

[0009] In conjunction with the first aspect, in one embodiment, the cross-sections of the anchor beam and the cross brace are configured as cross-shaped.

[0010] In conjunction with the first aspect, in one embodiment, the corbel is fixed to the tower column by a second pre-embedded component. The second pre-embedded component includes a second pre-embedded plate, a plurality of second shear keys, and a second perforated plate connector that are interconnected. The second pre-embedded plate is pre-embedded in the tower column and fixed to the corbel. The plurality of second shear keys and the second perforated plate connectors are pre-embedded in the tower column and fixed to the second pre-embedded plate.

[0011] In conjunction with the first aspect, in one embodiment, the anchor beam is further provided with anchoring structures at both ends, and the anchoring structures are fixed to the top of the anchor beam.

[0012] In conjunction with the first aspect, in one embodiment, a cable guide is inserted into the anchoring structure, one end of the cable guide is pre-embedded in the tower column, and the other end of the cable guide extends obliquely upward out of the tower column.

[0013] Secondly, embodiments of this application provide a design method for a cable tower steel anchor beam structure, which includes the following steps: The dimensions of the anchor beam and the bracket are determined based on the cable force and the cable angle. Based on the uniformly distributed longitudinal load on the side wall of the tower column Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace ; Based on the axial force of the cross brace and cross brace cross area Calculate the axial stress of the cross brace. If the axial stress of the cross brace Less than the allowable stress of the steel If the axial stress of the cross brace is [value missing], then the requirement is met. Greater than the allowable stress of steel Then increase the thickness of the cross brace. Continue until the requirements are met.

[0014] In conjunction with the second aspect, in one embodiment, the uniformly distributed load along the longitudinal bridge direction based on the tower column sidewall... Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace Previously, it also included: Based on the stress at the center of the bottom plate of the crossbeam in the cable anchor zone and the thickness of the bottom plate of the beam Calculate the uniformly distributed longitudinal load on the sidewall of the tower column. ; Calculate the bending moment of inertia of the tower wall in the longitudinal direction based on the thickness of the tower wall in the longitudinal direction. ; Based on the bending moment of inertia of the tower wall in the longitudinal direction of the bridge , elastic modulus of concrete Calculate the span of the longitudinal bridge to the tower wall Calculate the mid-span displacement stiffness of the tower wall in the longitudinal direction. and longitudinal bridge mid-span displacement stiffness of the second span of the tower wall ; Based on the elastic modulus of steel Cross-sectional area of ​​the cross brace and cross brace length Calculate the axial compressive stiffness of the cross brace .

[0015] In conjunction with the second aspect, in one implementation, the design method further includes: Based on the shear bearing capacity of a single bolt and cross brace axial force Calculate the minimum number of bolts required between the single-sided cross brace and the support assembly. .

[0016] The beneficial effects of the technical solutions provided in this application include: By installing transverse braces on both sides of the anchor beam along the transverse direction of the bridge, support is provided for the bottom plate of the upper crossbeam inside the tower column. This reduces the calculated span of the tower wall in the longitudinal direction of the bridge, reduces the local bending moment effect of the tower wall in the longitudinal direction caused by the axial force of the bottom plate of the upper crossbeam, ensures that the local stress of the tower wall meets the requirements, and facilitates the setting of maintenance access. This solves the technical problem in related technologies where transverse diaphragms cannot be installed inside the tower column in the cable anchor area, resulting in the tower wall in the longitudinal direction of the bridge being unable to withstand the axial force of the bottom plate of the upper crossbeam in the box section. Consequently, the bridge tower cannot be equipped with a box-shaped upper crossbeam, cannot provide a complete maintenance access, and increases the safety risks for maintenance personnel. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a cable tower steel anchor beam structure provided in an embodiment of this application; Figure 2 A side view of a cable tower steel anchor beam structure provided in an embodiment of this application; Figure 3 for Figure 2 AA section view; Figure 4 for Figure 2 BB section view; Figure 5 for Figure 3 CC section view; Figure 6 for Figure 3 DD sectional view; Figure 7 for Figure 3 EE sectional view; Figure 8 This is a schematic diagram of a cable tower steel anchor beam structure and an upper crossbeam bottom plate provided in an embodiment of this application.

[0019] In the diagram: 1. Tower column; 2. Anchor beam; 3. Corbel; 4. Cross brace; 5. Support assembly; 6. First embedded assembly; 61. First embedded plate; 62. First shear key; 63. First perforated plate connector; 7. Splicing plate; 8. Second embedded assembly; 81. Second embedded plate; 82. Second shear key; 83. Second perforated plate connector; 9. Anchoring structure; 10. Cable guide. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0021] This application provides a steel anchor beam structure and design method for cable towers, which can solve the technical problem that the tower column cannot be equipped with transverse diaphragms inside the tower column in the cable anchor area, resulting in the tower column's longitudinal bridge wall being unable to withstand the axial force of the bottom plate of the box-shaped crossbeam, and thus the bridge tower cannot be equipped with a box-shaped upper crossbeam, which cannot provide a complete maintenance passage and increases the safety risks for maintenance personnel.

[0022] See Figure 1-4As shown in the figure, this application provides a cable tower steel anchor beam structure, which includes: a tower column 1, an anchor beam 2, and a cross brace 4. The tower column 1 has a cavity; the anchor beam 2 is installed in the cavity along the longitudinal direction of the bridge and is fixedly connected to the two inner side walls of the tower column 1. The anchor beam 2 has brackets 3 at both ends, the brackets 3 are fixed to the bottom of the anchor beam 2, and the brackets 3 are fixed to the tower column 1; the cross brace 4 is fixed to both sides of the anchor beam 2 along the transverse direction of the bridge and is fixedly connected to the other two inner side walls of the tower column 1.

[0023] In this embodiment, the transverse brace 4 is fixedly installed on both sides of the anchor beam 2 along the transverse bridge direction. The transverse brace 4 is welded to the anchor beam 2 and fixed to the inner wall of the tower column 1. The transverse brace 4 provides support for the bottom plate of the upper transverse beam inside the tower column 1, reducing the calculated span of the tower column in the longitudinal bridge direction, reducing the local bending moment effect of the tower wall in the longitudinal bridge direction caused by the axial force of the bottom plate of the upper transverse beam, ensuring that the local stress of the tower wall meets the requirements, and facilitating the setting of maintenance passages. The anchor beam 2 is supported by the... On the bracket 3, the anchor beam 2 is provided with multiple elongated holes on one side along the longitudinal direction of the bridge. A sliding plate is provided between the anchor beam 2 and the bracket 3 to ensure that the anchor beam 2 can slide freely along the longitudinal direction of the bridge at the support end. After the cable tensioning process is completed, the anchor beam 2 is bolted to the bracket 3 with high-strength bolts. The steel anchor beam of the cable tower has a compact structure, does not affect the maintenance passage and elevator setting inside the tower column 1, and does not occupy the tensioning space of the upper and lower adjacent anchor beams 2. The anchor beam spacing can be evenly arranged according to the conventional spacing.

[0024] This embodiment provides support for the bottom plate of the upper crossbeam inside the tower column 1 by setting the transverse bracing 4 on both sides of the anchor beam 2 along the transverse direction of the bridge. This reduces the calculated span of the tower wall in the longitudinal direction of the bridge, reduces the local bending moment effect of the tower wall in the longitudinal direction caused by the axial force of the bottom plate of the upper crossbeam, ensures that the local stress of the tower wall meets the requirements, and facilitates the setting of maintenance access. It solves the technical problem in related technologies where the tower column cable anchor area cannot be equipped with transverse diaphragms inside the tower column, resulting in the tower wall in the longitudinal direction of the bridge being unable to withstand the axial force of the bottom plate of the upper crossbeam of the box section. Consequently, the bridge tower cannot be equipped with a box-shaped upper crossbeam, cannot provide a complete maintenance access, and increases the safety risks for maintenance personnel.

[0025] Further, see Figure 1 As shown, in some embodiments, the cross brace 4 is connected to a support assembly 5, and the support assembly 5 is fixed to the tower column 1 via a first pre-embedded assembly 6. The first pre-embedded assembly 6 includes a first pre-embedded plate 61, a plurality of first shear keys 62, and a first perforated plate connector 63 that are interconnected. The first pre-embedded plate 61 is pre-embedded in the tower column 1 and is fixed to the support assembly 5. The plurality of first shear keys 62 and the first perforated plate connector 63 are pre-embedded in the tower column 1 and are fixed to the first pre-embedded plate 61.

[0026] In this embodiment, exemplary, the support assembly 5 includes a first top plate and a first bottom plate connected to each other. The first top plate is connected to the first bottom plate via a first web plate. The first top plate, the first bottom plate, and the first web plate are all welded to the first embedded plate 61. The top plate of the cross brace 4 is bolted to the first top plate, and the bottom plate of the cross brace 4 is bolted to the first bottom plate. The bottom plate of the cross brace 4 is supported on the first bottom plate and bolted to the first bottom plate. The first shear key 62 and the first perforated plate connector 63 are embedded in the tower column 1 and fixed to the first embedded plate 61. Multiple first shear keys 62 and first perforated plate connectors 63 achieve a fixed connection between the support assembly 5 and the tower column 1.

[0027] Further, see Figure 1 As shown, in some embodiments, the cross brace 4 is bolted to the support assembly 5 via a splicing plate 7.

[0028] In this embodiment, the top plate of the cross brace 4 and the top plate of the support assembly 5 are both sandwiched between the two splicing plates 7. The cross brace 4 has multiple elongated holes along the longitudinal direction of the bridge on the side away from the anchor beam 2 to accommodate the deformation of the anchor beam 2 and the displacement of the cross brace 4 during the tensioning of the cable. After the tensioning process of the cable is completed, the splicing plate 7 is bolted to the cross brace 4 and the support assembly 5 with high-strength bolts.

[0029] Further, see Figure 1 , Figure 3 and Figure 4 As shown, in some embodiments, the cross sections of the anchor beam 2 and the cross brace 4 are set in a cross shape.

[0030] In this embodiment, the cross brace 4 includes a second top plate and a second bottom plate that are connected to each other. The second top plate is connected to the second bottom plate through a second web plate. Exemplarily, the cross section of the cross brace 4 in the vertical direction is set to be rectangular. The top plate of the anchor beam 2 is located at the same horizontal position as the second top plate, and the bottom plate of the anchor beam 2 is located at the same horizontal position as the second bottom plate. The cross brace 4 is fixed to the anchor beam 2 at the center position of the anchor beam 2 and forms a cross support structure in the horizontal direction.

[0031] Further, see Figure 1 and Figure 2As shown, in some embodiments, the corbel 3 is fixed to the tower column 1 by a second pre-embedded component 8. The second pre-embedded component 8 includes a second pre-embedded plate 81, a plurality of second shear keys 82 and a second perforated plate connector 83 connected to each other. The second pre-embedded plate 81 is pre-embedded in the tower column 1 and fixed to the corbel 3. The plurality of second shear keys 82 and the second perforated plate connector 83 are pre-embedded in the tower column 1 and fixed to the second pre-embedded plate 81.

[0032] In this embodiment, the anchor beam 2 has multiple elongated holes on one side along the longitudinal direction of the bridge. The corbel 3 includes a third top plate and a third bottom plate that are connected to each other. The third top plate is connected to the third bottom plate through a third web plate. The third top plate supports the bottom plate of the anchor beam 2 and is bolted to the bottom plate of the anchor beam 2. A top plate is provided between the third top plate and the bottom plate of the anchor beam 2. The third web plate is provided with stiffening ribs. The third web plate is welded to the second embedded plate 81.

[0033] Further, see Figure 1 and Figure 2 As shown, in some embodiments, the anchor beam 2 is further provided with anchoring structures 9 at both ends, and the anchoring structures 9 are fixed to the top of the anchor beam 2.

[0034] In this embodiment, the anchoring structure 9 includes an anchor plate and a bearing plate that are fitted together. The bearing plate is connected to the web of the anchor beam 2. A support plate is provided under the bearing plate. The cable anchor head acts on the anchor plate and transmits the cable force to the anchor beam 2 through the bearing plate and the support plate.

[0035] Further, see Figure 1 and Figure 2 As shown, in some embodiments, a cable guide 10 is inserted into the anchoring structure 9, one end of the cable guide 10 is pre-embedded in the tower column 1, and the other end of the cable guide 10 extends obliquely upward out of the tower column 1.

[0036] In this embodiment, a through hole is provided in the center of the anchor plate, and the cable guide 10 passes through the through hole and is set perpendicular to the anchor plate. The cable guide 10 is mainly used to reserve holes and guide the stay cables during the construction of the tower column 1.

[0037] This application provides a design method for a cable tower steel anchor beam structure, which includes the following steps: S1: Determine the dimensions of anchor beam 2 and bracket 3 based on the cable force and cable angle.

[0038] S2: Based on the uniformly distributed longitudinal load on the side wall of the tower column Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace .

[0039] S3: Based on the axial force of the cross brace and cross brace cross area Calculate the axial stress of the cross brace. If the axial stress of the cross brace Less than the allowable stress of the steel If the axial stress of the cross brace is [value missing], then the requirement is met. Greater than the allowable stress of steel Then increase the thickness of cross brace 4. Continue until the requirements are met.

[0040] In this embodiment, the anchorage points of the main tower side stay cables are first adjusted so that the center of the steel anchor beam structure at the lower edge of the box-section crossbeam in the cable anchorage area of ​​the tower is aligned with the center of the bottom plate of the box-section crossbeam in the cable anchorage area of ​​the tower. Based on the cable force and cable angle and in accordance with the conventional steel anchor beam design, the relevant structures and dimensions of the anchor beam 2, corbel 3, second embedded component 8, anchorage structure 9, and cable guide 10 are determined. Then, based on the longitudinal uniformly distributed load on the tower column sidewall... Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace axial force of cross brace Satisfy the following formula: In the formula The longitudinal load on the side wall of the tower column is uniformly distributed along the bridge direction. For the axial compressive stiffness of the cross brace , The longitudinal stiffness of the bridge tower wall at mid-span is the displacement stiffness in the first span. The longitudinal stiffness of the bridge towards the tower wall at the mid-span is determined by the axial force of the cross brace. and cross brace cross area Calculate the axial stress of the cross brace. If the axial stress of the cross brace Less than the allowable stress of the steel If the axial stress of the cross brace is [value missing], then the requirement is met. Greater than the allowable stress of steel Then increase the thickness of cross brace 4. Continue until the requirements are met.

[0041] Furthermore, in some embodiments, the uniformly distributed load along the longitudinal bridge direction based on the tower sidewall is... Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace Previously, it also included: S201: Based on the stress at the center of the bottom plate of the crossbeam in the cable anchor zone and the thickness of the bottom plate of the beam Calculate the uniformly distributed longitudinal load on the sidewall of the tower column. ; S202: Calculate the bending moment of inertia of the tower wall in the longitudinal direction based on the thickness of the tower wall in the longitudinal direction. .

[0042] S203: Based on the longitudinal bending moment of inertia of the tower wall , elastic modulus of concrete Calculate the span of the longitudinal bridge to the tower wall Calculate the mid-span displacement stiffness of the tower wall in the longitudinal direction. and longitudinal bridge mid-span displacement stiffness of the second span of the tower wall .

[0043] S204: Based on the elastic modulus of steel Cross-sectional area of ​​the cross brace and cross brace length Calculate the axial compressive stiffness of the cross brace .

[0044] In this embodiment, as Figure 2 , Figure 3 and Figure 8 As shown, based on the stress at the center of the bottom plate of the crossbeam in the cable anchor zone... and the thickness of the bottom plate of the beam Calculate the uniformly distributed longitudinal load on the sidewall of the tower column. The longitudinal uniformly distributed load on the side wall of the tower column The uniformly distributed load in the longitudinal direction borne by the tower wall caused by the axial force on the bottom plate of the crossbeam, and the uniformly distributed load in the longitudinal direction on the side wall of the tower column. Satisfy the following formula: In the formula The stress at the center of the bottom plate of the crossbeam in the cable anchor zone. The thickness of the bottom plate of the crossbeam. The load is a uniformly distributed load along the longitudinal direction of the bridge on the side wall of the tower column.

[0045] Based on the longitudinal tower wall thickness, the effective influence height range of the axial force on the bottom plate of the crossbeam is obtained. Then, the longitudinal bending moment of inertia of the tower wall within the effective influence height range of the axial force on the bottom plate of the crossbeam was calculated. According to the longitudinal bending moment of the tower wall , elastic modulus of concrete Calculate the span of the longitudinal bridge to the tower wall Calculate the mid-span displacement stiffness of the tower wall in the longitudinal direction. and longitudinal bridge mid-span displacement stiffness of the second span of the tower wall ,like Figure 1-4 As shown, the longitudinal bridge-to-tower wall mid-span displacement stiffness is... The longitudinal bridge tower wall's mid-span displacement stiffness under uniformly distributed load is the longitudinal bridge tower wall's first mid-span displacement stiffness. Satisfy the following formula: Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall The longitudinal bridge tower wall's mid-span displacement stiffness under concentrated load at mid-span is given by [reference to specific parameters]. The longitudinal bridge tower wall's second mid-span displacement stiffness is also given by [reference to specific parameters]. Satisfy the following formula: In the formula The elastic modulus of concrete. For the longitudinal bending moment of the tower wall, Calculate the span of the longitudinal bridge tower wall.

[0046] Set the cross brace 4 and anchor beam 2 to the same height, such as Figure 1 , Figure 2 and Figure 7 As shown, based on the determined anchor beam height Obtain the height of the cross brace Anchor beam height and cross brace height Satisfy the following formula: The cross-section of the cross brace 4 is rectangular, and the thickness of the top plate, bottom plate, and web plate of the cross brace 4 are equal. Figure 3 , Figure 5 and Figure 6 As shown, the thickness of the top plate, bottom plate, and web plate of the cross brace 4 is set to... The cross-sectional area of ​​the horizontal brace satisfies the following formula: In the formula The height of the horizontal brace. The thickness of the wall panel for cross brace 4. The cross-sectional area of ​​the cross brace, and the axial compressive stiffness of the cross brace. Satisfy the following formula: In the formula The elastic modulus of steel, The cross-sectional area of ​​the horizontal brace. This is the length of the horizontal brace.

[0047] Furthermore, in some embodiments, the design method further includes: Based on the shear bearing capacity of a single bolt and cross brace axial force Calculate the minimum number of bolts required between the single-sided cross brace 4 and the support assembly 5. .

[0048] In this embodiment, as Figure 1-3As shown, the minimum number of bolts required between the single-sided cross brace 4 and the support assembly 5. Satisfy the following formula: In the formula For the shear bearing capacity of a single bolt, This is the axial force of the cross brace.

[0049] At the bottom edge of the crossbeam on the bridge tower without cross bracing 4, the bending moment borne by the tower column sidewall in the longitudinal direction at mid-span is: The bending moments borne by the tower column sidewalls at both ends in the longitudinal direction of the bridge are At the bottom edge of the crossbeam on the bridge tower with cross bracing 4, the bending moment borne by the tower column sidewall in the longitudinal direction at the mid-span is: The bending moments borne by the tower column sidewalls at both ends in the longitudinal direction of the bridge are The change in the mid-span bending moment of the tower sidewall in the longitudinal direction is The change in bending moment at both ends of the tower column sidewall in the longitudinal direction of the bridge is .

[0050] Before the concrete pouring of the main tower column 1, the anchor beam 2 is welded to the cross brace 4 at its center to form a cross support structure. The anchor beam 2 and the corbel 3, as well as the cross brace 4 and the support component 5, are temporarily connected. After the cross brace 4 and the anchor beam 2 are hoisted into place as a whole, the first embedded component 6 and the second embedded component 8 are firmly connected to the construction stiffening frame and steel reinforcement of the tower column 1. The corresponding segment of the tower column 1 is then poured with concrete. After the tower construction is completed, the temporary connection between the anchor beam 2 and the corbel 3, as well as the cross brace 4 and the support component 5, is released. The main beam and its ancillary works are then constructed, and the stay cables are hoisted and tensioned in batches. Under dead load, the longitudinal horizontal tension of the stay cables is borne by the anchor beam 2. The elongated holes of the anchor beam 2 and the cross brace 4 can accommodate the deformation and displacement caused by the tensioning of the stay cables. After all the tensioning procedures of the stay cables during construction are completed, the anchor beam 2 and the corbel 3, as well as the cross brace 4 and the support component 5, are bolted together to achieve a solid connection between all structures and the tower. Figure 8 As shown, after the bridge is completed, the cross brace 4 provides support to the tower wall at the center of the tower wall in the longitudinal direction of the tower column 1, reducing the local calculated span of the tower wall in the longitudinal direction of the tower wall, reducing the local bending moment effect of the tower wall in the longitudinal direction of the tower wall caused by the axial force of the bottom plate of the upper cross beam, and ensuring that the local stress of the tower wall can meet the requirements. The cross beam in the anchorage area of ​​the cable tower can adopt a box section with good landscape effect, strong torsional resistance, convenient access for main tower maintenance, and safety of maintenance personnel, so that the overall stress of the main tower is better.

[0051] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and 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. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" 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 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 between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0052] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A cable tower steel anchor beam structure, characterized in that, It includes: Tower column (1), wherein the tower column (1) is provided with a cavity; Anchor beam (2), the anchor beam (2) is installed in the cavity along the longitudinal direction of the bridge and is fixedly connected to the two inner side walls of the tower column (1). The two ends of the anchor beam (2) are provided with brackets (3), the brackets (3) are fixed to the bottom of the anchor beam (2), and the brackets (3) are fixed to the tower column (1). The cross brace (4) is fixed on both sides of the anchor beam (2) along the transverse direction of the bridge and is fixedly connected to the other two inner side walls of the tower column (1).

2. The cable tower steel anchor beam structure as described in claim 1, characterized in that, The cross brace (4) is connected to a support assembly (5). The support assembly (5) is fixed to the tower column (1) via a first pre-embedded assembly (6). The first pre-embedded assembly (6) includes a first pre-embedded plate (61), a plurality of first shear keys (62), and a first perforated plate connector (63) that are connected to each other. The first pre-embedded plate (61) is pre-embedded in the tower column (1) and is fixed to the support assembly (5). The plurality of first shear keys (62) and the first perforated plate connector (63) are pre-embedded in the tower column (1) and are fixed to the first pre-embedded plate (61).

3. The cable tower steel anchor beam structure as described in claim 2, characterized in that, The cross brace (4) is bolted to the support assembly (5) via a splicing plate (7).

4. The cable tower steel anchor beam structure as described in claim 1, characterized in that, The cross sections of the anchor beam (2) and the cross brace (4) are set in a cross shape.

5. The cable tower steel anchor beam structure as described in claim 1, characterized in that, The corbel (3) is fixed to the tower column (1) by a second pre-embedded component (8). The second pre-embedded component (8) includes a second pre-embedded plate (81) connected to each other, a plurality of second shear keys (82) and a second perforated plate connector (83). The second pre-embedded plate (81) is pre-embedded in the tower column (1) and fixed to the corbel (3). The plurality of second shear keys (82) and the second perforated plate connector (83) are pre-embedded in the tower column (1) and fixed to the second pre-embedded plate (81).

6. The cable tower steel anchor beam structure as described in claim 1, characterized in that, The anchor beam (2) is also provided with anchoring structures (9) at both ends, and the anchoring structures (9) are fixed to the top of the anchor beam (2).

7. The cable tower steel anchor beam structure as described in claim 6, characterized in that, The anchoring structure (9) is equipped with a cable guide (10), one end of which is embedded in the tower column (1), and the other end of which extends obliquely upward out of the tower column (1).

8. A design method for a cable tower steel anchor beam structure as described in claim 1, characterized in that, It includes the following steps: The dimensions of the anchor beam (2) and the corbel (3) are determined based on the cable force and the cable angle. Based on the uniformly distributed longitudinal load on the side wall of the tower column Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace ; Based on the axial force of the cross brace and cross brace cross area Calculate the axial stress of the cross brace. If the axial stress of the cross brace Less than the allowable stress of the steel If the axial stress of the cross brace is [value missing], then the requirement is met. Greater than the allowable stress of steel Then increase the thickness of the cross brace (4). Continue until the requirements are met.

9. The design method as described in claim 8, characterized in that, According to the uniformly distributed load in the longitudinal direction of the tower sidewall Longitudinal bridge to tower wall mid-span displacement stiffness Longitudinal bridge mid-span displacement stiffness of the second span of the tower wall and cross brace axial compressive stiffness Calculate the axial force of the cross brace Previously, it also included: Based on the stress at the center of the bottom plate of the crossbeam in the cable anchor zone and the thickness of the bottom plate of the beam Calculate the uniformly distributed longitudinal load on the sidewall of the tower column. ; Calculate the bending moment of inertia of the tower wall in the longitudinal direction based on the thickness of the tower wall in the longitudinal direction. ; Based on the bending moment of inertia of the tower wall in the longitudinal direction of the bridge , elastic modulus of concrete Calculate the span of the longitudinal bridge to the tower wall Calculate the mid-span displacement stiffness of the tower wall in the longitudinal direction. and longitudinal bridge mid-span displacement stiffness of the second span of the tower wall ; Based on the elastic modulus of steel Cross-sectional area of ​​the cross brace and cross brace length Calculate the axial compressive stiffness of the cross brace .

10. The design method as described in claim 8, wherein the cross brace (4) is connected to a support assembly (5), characterized in that, The design method further includes: Based on the shear bearing capacity of a single bolt and cross brace axial force Calculate the minimum number of bolts required between the single-sided cross brace (4) and the support assembly (5). .

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