Prestressed concrete cable-stayed bridge cable-beam anchoring structure and bridge

Abstract

The application provides a prestressed concrete cable-stayed bridge cable-beam anchoring structure and a bridge, and relates to the field of bridges. A sleeve for passing a stay cable is arranged on an anchor block. One side of the anchor block adhering to the bottom surface of a box girder is a bonding surface, and the opposite side of the bonding surface is the anchoring surface of the anchor block. The anchoring surface is perpendicular to the axis of the sleeve. The surface between the bonding surface and the anchoring surface and adjacent to the anchoring surface is the four side surfaces of the anchor block. At least three side surfaces form an obtuse angle with the bottom surface of the box girder. The center of the opening of the sleeve on the anchoring surface is an anchoring point, and the anchoring point is coplanar with the center line of the diaphragm of the box girder adhering to the anchor block. In view of the problem that the unreasonable anchor block structure of the cable-stayed bridge leads to stress concentration and poor reliability, a space polyhedral structure is adopted to ensure that the angle between the lateral surface of the anchor block and the bottom surface of the box girder is obtuse, thereby optimizing the stress of the anchor block, making the internal steel anchoring structure of the anchor block reasonable, avoiding stress concentration, improving the construction convenience, and ensuring the structural quality.

Description

Technical Field

[0001] This invention relates to the field of bridges, specifically to a prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure and the bridge itself. Background Technology

[0002] As a special type of bridge structure, cable-stayed bridges have a complex force transmission mechanism between the cables and anchorages. The force transmitted by the cables after passing through the anchorages must meet engineering requirements and design specifications. Anchorages are used to connect the stay cables in prestressed concrete cable-stayed bridges. As the main load-bearing locations, the research and design of these anchorages need to consider various factors, such as the method of prestressing application, the arrangement and shape of the anchorages, etc.

[0003] In the "PK" section of the prestressed concrete cable-stayed bridge anchor block, the angle between the side of the anchor block and the bottom surface of the main beam in the transverse direction is less than 90°, forming a concave angle. The anchor block experiences complex stress at this location, and as a major stress-bearing area, the concave angle makes it difficult to arrange reinforcement, easily leading to stress concentration problems. Furthermore, it causes difficulties in formwork placement, making it hard to guarantee construction quality indicators such as the density of cast-in-place concrete, the thickness of the protective layer, and the surface appearance. Inspection, maintenance, and repair are also difficult, increasing the risk of cracking during operation and affecting structural durability. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure and bridge. The structure employs a spatial polyhedral structure to ensure that the angle between the transverse side of the anchor block and the bottom surface of the box girder is obtuse, thereby optimizing the stress on the anchor block, making the internal steel reinforcement anchorage structure of the anchor block reasonable, avoiding stress concentration, improving construction convenience, and thus ensuring structural quality.

[0005] The first objective of this invention is to provide an anchorage structure for prestressed concrete cable-stayed bridge beams, which adopts the following scheme:

[0006] It includes an anchor block, on which a sleeve is provided for the cable stays to pass through. The side of the anchor block that is in contact with the bottom surface of the box girder is the mating surface, and the side opposite to the mating surface is the anchor surface of the anchor block. The anchor surface is perpendicular to the axis of the sleeve. The four sides of the anchor block are located between the mating surface and the anchor surface and are adjacent to the anchor surface. At least three of the sides form an obtuse angle with the bottom surface of the box girder. The center of the opening of the sleeve on the anchor surface is the anchor point. The anchor point is coplanar with the center line of the transverse diaphragm of the box girder to which the anchor block is attached.

[0007] Furthermore, the anchor surface is a right trapezoid, with the intersection of the non-right-angled side and the base of the right trapezoid located on the mating surface, and the sleeve axis is arranged at an angle relative to the mating surface.

[0008] Furthermore, the sleeve is arranged coaxially with the stay cable, and the anchor connected to the end of the stay cable abuts against the anchor surface.

[0009] Furthermore, among the four sides of the anchor block, a pair of opposite sides arranged at intervals along the bridge are the first transverse bridge deck and the second transverse bridge deck. The first transverse bridge deck faces the side of the bridge tower connected by the cable stay, and the second transverse bridge deck faces away from the side of the bridge tower connected by the cable stay. The first transverse bridge deck forms an obtuse angle with the bottom surface of the box girder, and the second transverse bridge deck forms an obtuse angle with the bottom surface of the box girder.

[0010] Furthermore, among the four sides of the anchor block, a pair of opposite sides arranged at intervals along the transverse bridge are the first longitudinal bridge surface and the second longitudinal bridge surface. The first longitudinal bridge surface faces the transverse edge of the bridge, and the second longitudinal bridge surface faces the central axis of the bridge. The first longitudinal bridge surface forms an obtuse angle with the bottom surface of the box girder.

[0011] Furthermore, the horizontal distance between the end of the sleeve axis located on the anchor surface and the bridge centerline is greater than the distance between the end of the sleeve axis located on the joint surface and the bridge centerline, so that the end of the cable-stayed cable connected to the bridge tower extends upward and outward from the bridge in the transverse direction.

[0012] Furthermore, the ridge lines on the side of the anchor block are all parallel to the sleeve axis.

[0013] Furthermore, the first longitudinal bridge deck and the first transverse bridge deck are perpendicular.

[0014] A second objective of the present invention is to provide a bridge utilizing the prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in the first objective.

[0015] Furthermore, the bridge is equipped with multiple anchor blocks, each of which is fitted with a stay cable. One end of the stay cable is connected to the anchor block via an anchor, and the other end is connected to the bridge tower.

[0016] Compared with the prior art, the advantages and positive effects of this invention are:

[0017] (1) In response to the problem of stress concentration and poor reliability caused by the unreasonable structure of the anchor block of the current cable-stayed bridge, a spatial polyhedral structure is adopted to ensure that the angle between the side of the anchor block in the transverse direction and the bottom surface of the box girder is obtuse, thereby optimizing the stress of the anchor block, making the internal steel reinforcement anchoring structure of the anchor block reasonable, avoiding stress concentration, improving the convenience of construction, and thus ensuring the structural quality.

[0018] (2) Since the top of the stay cable in this invention extends to the outside of the anchor block, that is, the end of the stay cable located at the anchor block is closer to the central axis of the bridge than the end of the stay cable connected to the bridge tower. The anchor block is also subjected to stress in the transverse direction towards the outside of the bridge. Therefore, the face angle formed by the first longitudinal bridge surface and the bottom surface of the box girder is set as an obtuse angle, so that the internal steel reinforcement is arranged reasonably to resist the load of the stay cable force in the transverse direction towards the outside of the bridge.

[0019] (3) After adjusting the transverse side of the anchor block to an obtuse angle with the bottom surface of the box girder, the size of the joint surface was increased, and the stress level at the transverse intersection of the anchor block side and bottom surface was reduced. At the same time, the reinforcing bars can be arranged in a normal cross pattern, which facilitates construction and ensures the construction quality of the concrete at this point. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 This is a schematic diagram of the prestressed concrete cable-stayed bridge cable-stayed bridge anchorage structure installed on the bridge in Embodiments 1 and 2 of the present invention.

[0022] Figure 2 This is a transverse view of the bridge after the anchor block is installed on the bottom surface of the box girder in embodiments 1 and 2 of the present invention.

[0023] Figure 3 for Figure 2 A schematic diagram of the cross-section at point BB.

[0024] Figure 4 This is a schematic diagram of the anchor block structure in Embodiments 1 and 2 of the present invention.

[0025] Figure 5 This is a schematic diagram of the anchor surface of the anchor block in Embodiments 1 and 2 of the present invention.

[0026] Figure 6 This is a view of the anchor block after it has been installed on the bottom surface of the box girder in embodiments 1 and 2 of the present invention.

[0027] Among them, 1. Bridge, 2. Anchor block, 3. Sleeve, 4. Cable stay, 5. First transverse bridge deck, 6. Second transverse bridge deck, 7. First longitudinal bridge deck, 8. Second longitudinal bridge deck, 9. Anchor surface, 10. Joint surface, 11. Box girder bottom surface. Detailed Implementation

[0028] Example 1

[0029] In a typical embodiment of the present invention, such as Figures 1-6 As shown, an anchorage structure for a prestressed concrete cable-stayed bridge is presented.

[0030] The current design of anchor block 2 in the anchorage structure of the cable-stayed bridge has defects. Anchor block 2 is subjected to complex forces at the concave corner position. As the main stress position, the concave corner structure is inconvenient for steel reinforcement arrangement, which easily leads to stress concentration problems and affects the durability of the structure.

[0031] Based on this, this embodiment provides a prestressed concrete cable-stayed bridge cable beam anchorage structure, which adopts a spatial polyhedral structure anchor block 2 to ensure that the angle between the transverse side of the anchor block 2 and the bottom surface 11 of the box girder is obtuse, thereby optimizing the stress on the anchor block 2, making the internal steel reinforcement anchorage structure of the anchor block 2 reasonable, avoiding stress concentration, improving construction convenience, and thus ensuring structural quality.

[0032] The anchorage structure of the prestressed concrete cable-stayed bridge cable beam will be described in detail below with reference to the attached drawings.

[0033] In this embodiment, anchor block 2 is arranged at the beam end of the prestressed concrete box girder of section PK. Anchor block 2 is connected to the cable stay 4 of the prestressed concrete cable-stayed bridge. Anchor block 2 is located at the bottom of the intersection of the transverse diaphragm and the outer web of the main beam side box. Figure 1 As shown.

[0034] Anchor block 2 is an irregularly shaped polyhedral structure, comprising an anchor surface 9, side surfaces, and a mating surface 10. The stay cable 4 passes through anchor block 2 and connects to the anchorage. The side of the anchorage that abuts against anchor block 2 is the anchor surface 9. The side of anchor block 2 that mats with the bottom surface 11 of the box girder is the mating surface 10. The side surface of anchor block 2 is located between anchor surface 9 and mating surface 10 and is adjacent to anchor surface 9. Anchor block 2 comprises four side surfaces, which, together with mating surface 10, form the irregularly shaped polyhedral structure. The mating surface 10 corresponds to... Figures 2-6 In the middle, the surface efgh corresponds to anchor surface 9. Figures 2-6 The face in the adcf.

[0035] In this embodiment, as Figure 2 and Figure 3 As shown, a pair of opposite sides arranged at intervals along the longitudinal bridge are the first transverse bridge surface 5 and the second transverse bridge surface 6, and a pair of opposite sides arranged at intervals along the transverse bridge are the first longitudinal bridge surface 7 and the second longitudinal bridge surface 8.

[0036] The first horizontal bridge deck 5 faces the side of the bridge tower connected to the cable-stayed cable 4, and the first horizontal bridge deck 5 corresponds to Figures 2-6 In the middle, the second horizontal bridge deck 6 is located on the side opposite to the bridge tower connected to the cable-stayed cable 4. The second horizontal bridge deck 6 corresponds to... Figures 2-6 In the middle, the face angle formed between the first transverse bridge surface 5 (face cdhg) and the bottom surface 11 of the box girder is an obtuse angle, and the face angle formed between the second transverse bridge surface 6 (face aef) and the bottom surface 11 of the box girder is an obtuse angle.

[0037] It should be noted that in this embodiment, the stay cable 4 corresponding to the anchor block 2 is inclined to the outside of the bridge 1 in the transverse direction, that is, the end of the stay cable 4 located at the anchor block 2 is closer to the central axis of the bridge 1 than the end of the stay cable 4 connected to the bridge tower.

[0038] The first longitudinal bridge deck 7 faces the transverse edge of bridge 1, and the first longitudinal bridge deck 7 corresponds to... Figures 2-6The second longitudinal bridge deck 8 faces the central axis of bridge 1, and the second longitudinal bridge deck 8 corresponds to... Figures 2-6 In the middle, the face angle formed between the first longitudinal bridge surface 7 (face adhe) and the bottom surface 11 of the box girder is an obtuse angle, while the face angle formed between the second longitudinal bridge surface 8 (face cfg) and the bottom surface 11 of the box girder is an acute angle. The edges of the side of the anchor block 2 are all parallel to the axis of the sleeve 3; the first longitudinal bridge surface 7 (face adhe) and the first transverse bridge surface 5 (face cdhg) are perpendicular.

[0039] like Figure 1 and Figure 2 As shown, the angle between the stay cable 4 at different positions and the horizontal plane varies in the longitudinal direction of the bridge. At the same time, the angle between the stay cable 4 at different positions and the horizontal plane in the transverse direction of the bridge also varies. The cable force is relatively large, with the maximum cable force reaching more than 900t. The cable force is mainly transmitted to the main beam, i.e., the box girder mentioned above, through the anchor block 2.

[0040] Anchor block 2 is provided with a sleeve for the stay cable 4 to pass through. The sleeve is arranged coaxially with the stay cable 4. The anchor connected to the end of the stay cable 4 abuts against the anchor surface 9 (face adcf). The center of the opening of the sleeve on the anchor surface 9 (face adcf) is the anchor point m. The anchor point m is coplanar with the center line of the transverse diaphragm of the box girder to which the anchor block 2 is attached.

[0041] The stress on the joint surface 10 (face efgh) between the anchor block 2 and the bottom surface 11 of the box girder is complex. A coordinate system is established at the anchor point m with the joint surface 10 (face efgh) as the reference. The cable force of the stay cable 4 is decomposed in this coordinate system. The anchor block 2 mainly bears the pressure perpendicular to the joint surface 10 (face efgh), the shear force parallel to the joint surface 10 (face efgh), and the bending moment.

[0042] The side of anchor block 2 intersects with the bottom surface 11 of box girder through multiple lines, such as... Figure 2 and Figure 3 As shown, the first intersection line formed between the first transverse bridge deck 5 (surface cdhg) and the bottom surface 11 of the box girder is a straight line that is close to the transverse direction. The principal tensile stress and principal compressive stress at the location of the first intersection line are relatively large. At the same time, due to the prestressing of the box girder transverse diaphragm and other loads, the location of the first intersection line is subjected to axial force, bending moment and shear force in both the transverse and longitudinal directions, resulting in complex stress and stress concentration. Therefore, the face angle at the corresponding location of the first intersection line is set as an obtuse angle to make the internal reinforcement arrangement more reasonable, reduce stress concentration and optimize the stress.

[0043] It should be noted that a second intersection line is formed between the second transverse bridge surface 6 (surface aef) and the bottom surface 11 of the box girder. The second intersection line is also a straight line that is close to the transverse direction of the bridge. In order to improve the ability of the anchor block 2 to resist complex forces, the face angle at the corresponding position of the second intersection line is also set as an obtuse angle, the size of the joint surface 10 (surface efgh) is enlarged, and stress concentration is reduced.

[0044] Understandably, referring to Figure 4 The bonding surface 10 (face efgh) is the largest outer surface on the entire anchor block 2. It is attached to the surface of the box girder to increase the stress area.

[0045] Combination Figure 3 and Figure 6 The third intersection line formed between the first longitudinal bridge deck 7 (face adhe) and the bottom surface 11 of the box girder is a straight line that is close to the longitudinal direction of the bridge. Since the upper end faces of the sleeve 3 and the stay cable 4 are both located away from the central axis of the bridge 1, the anchor block 2 is also subjected to stress in the transverse direction towards the outside of the bridge 1. Therefore, the face angle at the corresponding position of the third intersection line is set as an obtuse angle, so that the internal steel reinforcement is arranged reasonably, resisting the load of the stay cable 4 in the transverse direction towards the outside of the bridge 1, and further increasing the stress area and optimizing the stress distribution.

[0046] In addition, the fourth intersection line formed between the second longitudinal bridge surface 8 (surface cfg) and the bottom surface 11 of the box girder is a straight line that is close to the longitudinal direction of the bridge. Since the thickness of the anchor block 2 corresponding to this position is relatively small, the face angle at the position corresponding to the fourth intersection line can be set as an acute angle to conform to the direction of the edge line of the overall anchor block 2.

[0047] like Figures 2-4 As shown, the intersection point n between the centerline of the stay cable 4 and the joint surface 10 (surface efgh) is also the endpoint of the axis of the sleeve 3 facing the bottom surface 11 of the box girder, and also the intersection point between the centerline of the stay cable 4 and the bottom surface 11 of the box girder. In addition, the exit point between the stay cable 4 and the top surface of the box girder is arranged at intervals with the edge of the box girder.

[0048] Anchor point m on anchor block 2 is aligned with the center line of the transverse diaphragm along the bridge. Anchor surface 9 (face adcf) is always perpendicular to the center line of the stay cable 4. The edge of anchor surface 9 (face adcf) extends along the center line of the stay cable 4 and intersects with the bottom surface 11 of the box girder, forming the corresponding first transverse bridge surface 5 (face cdhg), first longitudinal bridge surface 7 (face adhe), second transverse bridge surface 6 (face aef), and second longitudinal bridge surface 8 (face cfg). Anchor surface 9 (face adcf) and side surface (face abe) extend along the straight line ab toward the bottom surface 11 of the box girder and are compared with the bottom surface 11 of the box girder at point f.

[0049] During the pouring of anchor block 2, at least three of the four sides of anchor block 2 form obtuse angles with the bottom surface 11 of the box girder, which facilitates the arrangement of internal reinforcement and the erection of external formwork. One of the sides forms a concave angle, where the stress is relatively small and the thickness is also small, thus having a smaller impact on the overall construction.

[0050] After adjusting the transverse side of anchor block 2 to an obtuse angle with the bottom surface 11 of the box girder, the size of the mating surface 10 (surface efgh) was increased, reducing the stress level at the transverse intersection of the side and bottom surfaces of anchor block 2. Simultaneously, the reinforcing bars can be arranged in a normal crisscross pattern, facilitating construction and ensuring the quality of the concrete at this location.

[0051] Example 2

[0052] In another typical embodiment of the present invention, such as Figures 1-6 As shown, a bridge using a prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure is presented.

[0053] Multiple anchor blocks 2 are installed on the bridge 1. Each anchor block 2 is equipped with a stay cable 4. One end of the stay cable 4 is connected to the anchor block 2 through an anchor, and the other end is connected to the bridge tower.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An anchorage structure for a prestressed concrete cable-stayed bridge cable beam, characterized in that, It includes an anchor block, on which a sleeve is provided for the cable stays to pass through. The side of the anchor block that is in contact with the bottom surface of the box girder is the mating surface, and the side opposite to the mating surface is the anchor surface of the anchor block. The anchor surface is perpendicular to the axis of the sleeve. The four sides of the anchor block are located between the mating surface and the anchor surface and are adjacent to the anchor surface. At least three of the sides form an obtuse angle with the bottom surface of the box girder. The center of the opening of the sleeve on the anchor surface is the anchor point. The anchor point is coplanar with the center line of the transverse diaphragm of the box girder to which the anchor block is attached. The anchor block has a spatial polyhedral structure; The anchor surface is a right trapezoid, and the intersection of the non-right-angled side and the base of the right trapezoid is located on the mating surface. The sleeve axis is arranged at an angle relative to the mating surface. The edges on the sides of the anchor block are all parallel to the sleeve axis.

2. The prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in claim 1, characterized in that, The sleeve is arranged coaxially with the stay cable, and the anchor connected to the end of the stay cable abuts against the anchor surface.

3. The prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in claim 1, characterized in that, Of the four sides of the anchor block, a pair of opposite sides arranged at intervals along the bridge are the first transverse bridge deck and the second transverse bridge deck. The first transverse bridge deck faces the side of the bridge tower connected by the cable stay, and the second transverse bridge deck faces away from the side of the bridge tower connected by the cable stay. The first transverse bridge deck forms an obtuse angle with the bottom surface of the box girder, and the second transverse bridge deck forms an obtuse angle with the bottom surface of the box girder.

4. The prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in claim 1 or 3, characterized in that, Of the four sides of the anchor block, a pair of opposite sides arranged at intervals along the transverse bridge are the first longitudinal bridge surface and the second longitudinal bridge surface. The first longitudinal bridge surface faces the transverse edge of the bridge, and the second longitudinal bridge surface faces the central axis of the bridge. The first longitudinal bridge surface forms an obtuse angle with the bottom surface of the box girder.

5. The prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in claim 1, characterized in that, The horizontal distance between the end of the sleeve axis located on the anchor surface and the central axis of the bridge is greater than the distance between the end of the sleeve axis located on the joint surface and the central axis of the bridge, so that the end of the cable-stayed cable connected to the bridge tower extends upward and outward of the bridge across the transverse bridge.

6. The prestressed concrete cable-stayed bridge cable-stayed beam anchorage structure as described in claim 4, characterized in that, The first longitudinal bridge deck and the first transverse bridge deck are perpendicular.

7. A bridge, characterized in that, The anchorage structure of the prestressed concrete cable-stayed bridge cable beam as described in any one of claims 1-6 is used.

8. The bridge as described in claim 7, characterized in that, The bridge is equipped with multiple anchor blocks, each of which is fitted with a stay cable. One end of the stay cable is connected to the anchor block via an anchor, and the other end is connected to the bridge tower.

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