Vertical prestress tensioning and anchoring structure for cantilever beam

Abstract

The utility model provides a vertical prestress tension anchoring structure of a suspended pouring beam, which is characterized in that a corrugated pipe is vertically arranged in a concrete base body, an anchor lower base plate is arranged in the concrete base body and on the corrugated pipe, the anchor lower base plate is gradually thinned inwards from top to bottom, and the top of the anchor lower base plate is exposed on the concrete base body. The limiting plate is horizontally arranged on the top of the anchor lower cushion plate, the working anchor is horizontally arranged on the limiting plate, the vertical prestressed tendon is arranged in the concrete base body, vertically penetrates through the corrugated pipe, the anchor lower cushion plate, the limiting plate and the working anchor and is exposed on the working anchor, and the working clamping piece is connected to the vertical prestressed tendon in a sleeving mode and embedded in the top face of the working anchor. The vertical annular side wall of the anchoring cover plate is sleeved with and engaged with the working anchor in a threaded mode, a top plate of the anchoring cover plate abuts against the working clamping piece, and the vertical prestressed tendons further vertically penetrate through the arc-shaped penetrating holes of the top plate and are exposed on the top plate. According to the utility model, the tension prestress loss can be reduced, and the structural durability and safety are improved.

Description

Technical Field

[0001] This utility model relates to the field of bridge engineering technology, and in particular to the field of vertical prestressed tensioning construction technology for cantilever beams, specifically referring to a vertical prestressed tensioning anchorage structure for cantilever beams. Background Technology

[0002] Bridge engineering refers to the processes of bridge surveying, design, construction, maintenance, and inspection, as well as the science and engineering technology that studies these processes. It is a branch of civil engineering. The development of bridge engineering is primarily driven by the needs of transportation.

[0003] With the continuous advancement of science and technology, many high-pier, long-span cantilever bridges have emerged. To reduce cracking caused by excessive shear force and other factors inside the cantilever beam, vertical prestress is applied to the beam in advance to improve the shear bearing capacity of the entire beam. The tensioning of vertical prestressing tendons can effectively prevent diagonal cracks in the beam, ensuring the safety and durability of the structure.

[0004] Before pouring the concrete for the cantilever beam, the corrugated pipes, spiral reinforcement, and anchor plates are installed. The corrugated pipes are vertically positioned, and the anchor plates are placed on top of them, tapering inwards from top to bottom. The spiral reinforcement is vertically positioned and fitted over the anchor plates. Vertical prestressing tendons are typically vertical prestressed steel strands, which are vertically threaded through the corrugated pipes and anchor plates. Prestressing is performed after the concrete strength and elastic modulus are not less than 90% of the design strength and the curing time has exceeded 10 days. A limiting plate is installed on the top of the anchor plates, and a working anchor is installed on the limiting plate. The tendons are then manually threaded through the limiting plate and working anchor, followed by prestressing using jacks. During prestressing, the tension and elongation must be strictly controlled using oil... The tension force is controlled by the pump pressure gauge reading, and the actual elongation of the vertical prestressed steel strands is measured and recorded. After tensioning, working wedges are installed on the vertical prestressed steel strands, and then manually hammered into the top surface of the working anchor. This method creates many gaps between the steel strands, working anchors, and working wedges, resulting in loose connections. When the vertical prestressed steel strands are cut after tensioning, the shrinkage of the strands causes a significant loss of prestress. After tensioning and anchoring, the relative slippage between the vertical prestressed steel strands and the working wedges increases over time. At the same time, rainwater accumulates and erodes the prestressed anchoring site, leading to a greater loss of vertical prestress in the cantilever beam, which greatly affects the safety and durability of the cantilever structure.

[0005] Therefore, it is desirable to provide a vertical prestressed tensioning anchorage structure for cantilever beams, which can reduce the loss of tensioned prestress and improve the durability and safety of the structure. Utility Model Content

[0006] In order to overcome the shortcomings of the prior art, one objective of this utility model is to provide a vertical prestressed tensioning anchorage structure for cantilever beams, which can reduce the loss of tensioning prestress, improve the durability and safety of the structure, and is suitable for large-scale promotion and application.

[0007] Another objective of this invention is to provide a vertical prestressed tensioning and anchoring structure for cantilever beams, which is ingeniously designed, simple in structure, easy to construct, and has low construction costs, making it suitable for large-scale promotion and application.

[0008] To achieve the above objectives, this utility model provides a vertical prestressed tensioning anchorage structure for a cantilever beam, comprising a concrete matrix, a corrugated pipe, an anchor pad, a limiting plate, a working anchor, vertical prestressing tendons, and working wedges. The corrugated pipe is vertically disposed within the concrete matrix. The anchor pad is disposed within the concrete matrix and on the corrugated pipe. The anchor pad gradually tapers inwards from top to bottom, with its top exposed on the concrete matrix. The limiting plate is horizontally disposed on the top of the anchor pad. The working anchor is horizontally disposed on the limiting plate. The vertical prestressing tendons are disposed within the concrete matrix and vertically pass through the corrugated pipe, the anchor pad, the limiting plate, and the working anchor, and are exposed on the working anchor. The working wedges are sleeved on the vertical prestressing tendons and embedded in the top surface of the working anchor. The characteristic feature is that the vertical prestressed tensioning anchorage structure for the cantilever beam also includes an anchorage cover plate, wherein:

[0009] The anchoring cover plate includes a vertical annular sidewall and a top plate. The top plate is horizontally disposed on the vertical annular sidewall. The top plate has a vertically disposed perforation, which is a first arc-shaped hole. The first arc-shaped hole extends along the circumference of a horizontal circle, the center of which is located on the central axis of the vertical annular sidewall. The vertical annular sidewall is fitted with and threadedly engages the working anchor. The top plate abuts against the working clamp. The vertical prestressing tendon also vertically passes through the perforation and is exposed on the top plate.

[0010] Preferably, the anchoring cover plate is a steel cover plate.

[0011] Preferably, the bottom of the top plate protrudes downward to form a convex plate, and the convex plate is provided with a through hole in a vertical direction. The through hole is a second arc-shaped hole, which extends in an arc along the circumference of the horizontal circle and is located below the first arc-shaped hole. The convex plate abuts against the working clamp, and the vertical prestressing tendon also passes through the through hole in a vertical direction.

[0012] More preferably, the convex plate is a circular convex plate.

[0013] Preferably, the vertical prestressed tensioning anchorage structure of the cantilever beam further includes a pre-embedded drainage pipe, which is vertically embedded in the concrete matrix. The top of the anchor pad is vertically provided with a drainage hole, which is located outside the limiting plate. The upper end of the pre-embedded drainage pipe is inserted into the drainage hole.

[0014] More preferably, the pre-embedded drainage pipe is a drainage hose.

[0015] More preferably, there are multiple drainage holes, which are horizontally arranged around the limiting plate at intervals. The number of pre-embedded drainage pipes is the same as the number of drainage holes, and the pre-embedded drainage pipes and drainage holes are arranged in a one-to-one correspondence.

[0016] Furthermore, there are four drainage holes, which are located at the front, back, left, and right of the limiting plate, respectively.

[0017] Preferably, the vertical prestressing tendon is a vertical prestressed steel strand.

[0018] Preferably, the vertical prestressed tensioning anchorage structure of the cantilever beam further includes spiral reinforcement, which is vertically arranged in the concrete matrix and sleeved on the under-anchor pad.

[0019] The main beneficial effects of this utility model are as follows:

[0020] 1. In this utility model, the corrugated pipe of the vertical prestressed tensioning anchorage structure for a cantilever beam is vertically installed in the concrete matrix. The anchor pad is installed in the concrete matrix and on the corrugated pipe. The anchor pad gradually tapers inward from top to bottom, with its top exposed on the concrete matrix. A limiting plate is horizontally installed on the top of the anchor pad, and a working anchor is horizontally installed on the limiting plate. The vertical prestressing tendons are installed in the concrete matrix and vertically pass through the corrugated pipe, anchor pad, limiting plate, and working anchor, and are exposed on the working anchor. The working clamp is sleeved on... The vertical prestressing tendons are embedded in the top surface of the working anchor. The vertical annular sidewall of the anchoring cover plate is fitted with and threadedly engages with the working anchor. The top plate of the anchoring cover plate abuts against the working clamp. The top plate is provided with vertical perforations, which are first arc-shaped holes. The first arc-shaped holes extend along the circumference of a horizontal circle. The center of the horizontal circle is located on the central axis of the vertical annular sidewall. The vertical prestressing tendons are also vertically inserted through the perforations and exposed on the top plate. Therefore, it can reduce the loss of tension prestress, improve the durability and safety of the structure, and is suitable for large-scale promotion and application.

[0021] 2. In this utility model, the corrugated pipe of the vertical prestressed tensioning anchorage structure for a cantilever beam is vertically installed in the concrete matrix. The anchor pad is installed in the concrete matrix and on the corrugated pipe. The anchor pad gradually tapers inward from top to bottom, with its top exposed on the concrete matrix. A limiting plate is horizontally installed on the top of the anchor pad, and a working anchor is horizontally installed on the limiting plate. The vertical prestressing tendons are installed in the concrete matrix and vertically pass through the corrugated pipe, anchor pad, limiting plate, and working anchor, and are exposed on the working anchor. The working clamp is sleeved. The anchoring cover plate is attached to the vertical prestressing tendons and embedded in the top surface of the working anchor. The vertical annular sidewall of the anchoring cover plate is fitted with and threaded into the working anchor. The top plate of the anchoring cover plate abuts against the working clamp. The top plate is provided with vertical perforations, which are first arc-shaped holes. The first arc-shaped holes are provided along the circumference of a horizontal circle. The center of the horizontal circle is located on the central axis of the vertical annular sidewall. The vertical prestressing tendons are also vertically inserted through the perforations and exposed on the top plate. Therefore, its design is ingenious, its structure is simple, its construction is convenient, its construction cost is low, and it is suitable for large-scale promotion and application.

[0022] These and other objects, features and advantages of this utility model will be fully apparent from the following detailed description and drawings, and can be achieved by the means, devices and combinations thereof specifically pointed out in the description of the utility model. Attached Figure Description

[0023] Figure 1 This is a partial front sectional view of a specific embodiment of the vertical prestressed tensioning and anchoring structure for cantilever beams of this utility model.

[0024] Figure 2 yes Figure 1 A partially enlarged schematic diagram of the structure shown.

[0025] Figure 3 yes Figure 1 The diagram shows a partial exploded view of the front section of a specific embodiment.

[0026] Figure 4 yes Figure 3 A partially enlarged schematic diagram of the structure shown.

[0027] (Symbol Explanation)

[0028] 1 Concrete substrate; 2 Corrugated pipe; 3 Anchor pad; 4 Limiting plate; 5 Working anchor; 6 Vertical prestressing tendon; 7 Working wedge; 8 Anchor cover plate; 9 Vertical annular sidewall; 10 Top plate; 11 Perforation; 12 Convex plate; 13 Through hole; 14 Embedded drainage pipe; 15 Drainage hole; 16 Spiral reinforcement. Detailed Implementation

[0029] In order to better understand the technical content of this utility model, the following embodiments are provided for detailed description.

[0030] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 utility model.

[0031] Please see Figures 1-4 As shown, in a specific embodiment of this utility model, the vertical prestressed tensioning anchorage structure of the cantilever beam includes a concrete substrate 1, a corrugated pipe 2, an anchor pad 3, a limiting plate 4, a working anchor 5, vertical prestressing tendons 6, working wedges 7, and an anchorage cover plate 8, wherein:

[0032] The corrugated pipe 2 is vertically arranged in the concrete matrix 1. The anchor pad 3 is arranged in the concrete matrix 1 and on the corrugated pipe 2. The anchor pad 3 gradually tapers inward from top to bottom. The top of the anchor pad 3 is exposed on the concrete matrix 1. The limiting plate 4 is horizontally arranged on the top of the anchor pad 3. The working anchor 5 is horizontally arranged on the limiting plate 4. The vertical prestressing tendon 6 is arranged in the concrete matrix 1 and vertically passes through the corrugated pipe 2, the anchor pad 3, the limiting plate 4 and the working anchor 5, and is exposed on the working anchor 5. The working clamp 7 is sleeved on the vertical prestressing tendon 6 and embedded in the top surface of the working anchor 5.

[0033] The anchoring cover plate 8 includes a vertical annular sidewall 9 and a top plate 10. The top plate 10 is horizontally disposed on the vertical annular sidewall 9. The top plate 10 is vertically provided with a through hole 11. The through hole 11 is a first arc-shaped hole. The first arc-shaped hole extends along the circumference of a horizontal circle. The center of the horizontal circle is located on the central axis of the vertical annular sidewall. The vertical annular sidewall 9 is fitted with and threadedly engages with the working anchor 5. The top plate 10 abuts against the working clamp 7. The vertical prestressing tendon 6 also vertically passes through the through hole 11 and is exposed on the top plate 10.

[0034] The anchoring cover plate 8 can be a cover plate of any suitable material. In a specific embodiment of this utility model, the anchoring cover plate 8 is a steel cover plate.

[0035] The bottom of the top plate 10 can have any suitable configuration; please refer to [link / reference]. Figures 1-4As shown, in a specific embodiment of this utility model, the bottom of the top plate 10 protrudes downward to form a convex plate 12. The convex plate 12 is provided with a through hole 13, which is a second arc-shaped hole. The second arc-shaped hole extends along the circumference of the horizontal circle and is located below the first arc-shaped hole 11. The convex plate 12 abuts against the working clamp 7, and the vertical prestressing tendon 6 also passes through the through hole 13 vertically.

[0036] The convex plate 12 can have any suitable shape. In a specific embodiment of the present invention, the convex plate 12 is a circular convex plate.

[0037] The vertical prestressed tensioning anchorage structure of the cantilever beam may also include any other suitable components; please refer to [link / reference]. Figure 1 and Figure 3 As shown, in a specific embodiment of this utility model, the vertical prestressed tensioning anchorage structure of the cantilever beam further includes a pre-embedded drainage pipe 14, which is vertically embedded in the concrete substrate 1. The top of the anchor pad 3 is vertically provided with a drainage hole 15, which is located outside the limiting plate 4. The upper end of the pre-embedded drainage pipe 14 is inserted into the drainage hole 15.

[0038] The pre-embedded drainage pipe 14 can be any suitable drainage pipe. In a specific embodiment of this utility model, the pre-embedded drainage pipe 14 is a drainage hose.

[0039] The number of drainage holes 15 can be determined as needed. More preferably, there are multiple drainage holes 15, which are horizontally arranged around the limiting plate 4 at intervals. The number of pre-embedded drainage pipes 14 is the same as the number of drainage holes 15, and the pre-embedded drainage pipes 14 and drainage holes 15 are arranged in a one-to-one correspondence. The term "multiple" refers to two or more. In a specific embodiment of this utility model, there are four drainage holes 15, which are located at the front, back, left, and right of the limiting plate 4, respectively.

[0040] The vertical prestressing tendon 6 can be any suitable prestressing tendon. In a specific embodiment of this utility model, the vertical prestressing tendon 6 is a vertical prestressing steel strand (vertical prestressing steel bundle).

[0041] The vertical prestressed tensioning anchorage structure of the cantilever beam may also include any other suitable components; please refer to [link / reference]. Figure 1 and Figure 3 As shown, in a specific embodiment of this utility model, the vertical prestressed tensioning anchorage structure of the cantilever beam further includes a spiral bar 16, which is vertically arranged in the concrete matrix 1 and sleeved on the under-anchor pad 3.

[0042] The construction process of this utility model is briefly described as follows:

[0043] (1) Before pouring the concrete of the cantilever beam, install the corrugated pipe 2, the anchor plate 3, the pre-embedded drainage pipe 14 (if any) and the spiral reinforcement 16 (if any). The corrugated pipe 2 is set vertically, the anchor plate 3 is set on the corrugated pipe 2, the upper end of the pre-embedded drainage pipe 14 is inserted into the drainage hole 15 at the top of the anchor plate 3, the spiral reinforcement 16 is sleeved on the outside of the anchor plate 3, and the vertical prestressing tendon 6 is taken as a vertical prestressing steel strand, and the vertical prestressing steel strand is vertically passed through the corrugated pipe 2 and the anchor plate 3.

[0044] (2) Pour the concrete of the cantilever beam to form the concrete matrix 1. The prestressing tensioning is carried out after the concrete strength and elastic modulus are not less than 90% of the design strength and the age is more than 10 days. The through holes 13 (if any) and perforations 11 of the limiting plate 4, working anchor 5 and anchor cover plate 8 are fitted on the vertical prestressing steel strands. The limiting plate 4 is installed on the top of the anchor pad 3, the working anchor 5 is installed on the limiting plate 4, the anchor cover plate 8 is placed on the working anchor 5, and then the prestressing tensioning is carried out by the jack.

[0045] (3) After tensioning, install the working clip 7 on the vertical prestressed steel strand, and then mechanically tighten the anchor cover plate 8 horizontally onto the working anchor 5 (until it cannot be tightened), press the working clip 7 into the top surface of the working anchor 5, so that the working clip 7 is closely attached to the vertical prestressed steel strand and the working anchor 5.

[0046] (4) Cut the vertical prestressed steel strands and tighten the anchor cover plate 8 again using mechanical horizontal screws (until it can no longer be tightened);

[0047] (5) Post-anchoring.

[0048] Therefore, in order to solve the problems of relative slippage between the vertical prestressing tendons and working wedges in cantilever beams and the impact of rainwater erosion, and to reduce the prestress loss of the vertical prestressing tendons, this utility model provides a vertical prestressing tensioning anchorage structure for cantilever beams. The anchorage cover plate, through the interlocking force between the threads, forcibly embeds the working wedges between the vertical prestressing tendons and the top surface of the working anchor. By adding an anchorage cover plate above the working anchor that can restrict the movement of the working wedges, the pressure applied by the anchorage cover plate and the friction between the vertical prestressing tendons and the working wedges work together to restrict relative slippage between the vertical prestressing tendons and the working wedges, greatly reducing prestress loss. At the same time, due to the protection of the anchorage cover plate, the corrosion of the vertical prestressing tendons and working wedges by rainwater and air is also reduced. In addition, drainage holes can be set vertically at the top of the anchor pad plate and outside the limiting plate for inserting the upper end of the pre-embedded drainage pipe for centralized drainage of the bridge deck, further reducing the erosive effect of rainwater. This utility model has low cost and high practicality, and greatly meets the construction needs of modern bridge engineering.

[0049] Compared with the prior art, the present invention has the following advantages:

[0050] 1. This utility model, by designing an anchoring cover plate, tightly fits the working wedge with the vertical prestressing tendon and the working anchor, reducing the relative slippage between them, thereby reducing the prestress loss caused by the relative slippage between the working wedge and the vertical prestressing tendon; by setting the anchoring cover plate to prevent rainwater and air from corroding the vertical prestressing tendon and the working wedge, the erosive effect of rainwater and air can be reduced, thereby reducing prestress loss and making the structure more durable and safe.

[0051] 2. This utility model can also discharge rainwater in a timely manner by pre-burying drainage pipes, which can further realize the bridge deck drainage function and prevent air and rainwater from eroding the vertical prestressing tendons and working clips.

[0052] 3. This utility model has low cost, simple structure, and is quick and convenient to install and disassemble;

[0053] 4. This utility model ensures the quality of prestressed construction and conforms to the concept of green construction.

[0054] In summary, the vertical prestressed tensioning anchorage structure for cantilever beams of this invention can reduce the loss of prestress during tensioning, improve the durability and safety of the structure, and is ingeniously designed, simple in structure, easy to construct, and low in construction cost, making it suitable for large-scale promotion and application.

[0055] Therefore, it is evident that the objective of this utility model has been fully and effectively achieved. The function and structural principles of this utility model have been demonstrated and explained in the embodiments. Without departing from the stated principles, any modifications can be made to the implementation methods. Therefore, this utility model includes all modified embodiments based on the spirit and scope of the claims.

Claims

1. A vertical prestressed tensioning anchorage structure for a cantilever beam, comprising a concrete matrix, a corrugated pipe, an anchor pad, a limiting plate, a working anchor, vertical prestressing tendons, and working wedges, wherein the corrugated pipe is vertically disposed in the concrete matrix, the anchor pad is disposed in the concrete matrix and disposed on the corrugated pipe, the anchor pad gradually tapers inward from top to bottom, the top of the anchor pad is exposed on the concrete matrix, the limiting plate is horizontally disposed on the top of the anchor pad, the working anchor is horizontally disposed on the limiting plate, the vertical prestressing tendons are disposed in the concrete matrix and vertically pass through the corrugated pipe, the anchor pad, the limiting plate, and the working anchor and are exposed on the working anchor, and the working wedges are sleeved on the vertical prestressing tendons and embedded in the top surface of the working anchor, characterized in that... The vertical prestressed tensioning anchorage structure of the cantilever beam also includes an anchorage cover plate, wherein: The anchoring cover plate includes a vertical annular sidewall and a top plate. The top plate is horizontally disposed on the vertical annular sidewall. The top plate has a vertically disposed perforation, which is a first arc-shaped hole. The first arc-shaped hole extends along the circumference of a horizontal circle, the center of which is located on the central axis of the vertical annular sidewall. The vertical annular sidewall is fitted with and threadedly engages the working anchor. The top plate abuts against the working clamp. The vertical prestressing tendon also vertically passes through the perforation and is exposed on the top plate.

2. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 1, characterized in that, The anchoring cover plate is a steel cover plate.

3. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 1, characterized in that, The bottom of the top plate protrudes downward to form a convex plate. The convex plate is provided with a through hole in the vertical direction. The through hole is a second arc-shaped hole. The second arc-shaped hole extends along the circumference of the horizontal circle and is located below the first arc-shaped hole. The convex plate abuts against the working clamp. The vertical prestressing tendon also passes through the through hole in the vertical direction.

4. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 3, characterized in that, The convex plate is a circular convex plate.

5. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 1, characterized in that, The vertical prestressed tensioning anchorage structure of the cantilever beam also includes a pre-embedded drainage pipe, which is vertically embedded in the concrete matrix. The top of the anchor pad is vertically provided with a drainage hole, which is located outside the limiting plate. The upper end of the pre-embedded drainage pipe is inserted into the drainage hole.

6. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 5, characterized in that, The pre-buried drainage pipe is a flexible drainage pipe.

7. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 5, characterized in that, The number of drainage holes is multiple, and the multiple drainage holes are arranged horizontally around the limiting plate at intervals. The number of pre-embedded drainage pipes is the same as the number of drainage holes, and the pre-embedded drainage pipes and drainage holes are arranged in a one-to-one correspondence.

8. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 7, characterized in that, The number of drainage holes is four, and the four drainage holes are located at the front, back, left, and right of the limiting plate, respectively.

9. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 1, characterized in that, The vertical prestressing tendons are vertical prestressed steel strands.

10. The vertical prestressed tensioning and anchoring structure for cantilever beams as described in claim 1, characterized in that, The vertical prestressed tensioning anchorage structure of the cantilever beam also includes spiral reinforcement, which is vertically arranged in the concrete matrix and sleeved on the under-anchor pad.

Images