A scour-resistant pile foundation structure
By setting up self-stressed pile foundation external form on the upper part of the bridge pile foundation, the combination of high-expanded concrete and external form steel bar frameworks is used to solve the exposed bars and corrosion problems of bridge pile foundation under river silt and sand erosion, which significantly improves the anti-shrink and seepage resistance and ensures the safety of the bridge.
Patent Information
- Application Number
- CN202422029124.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-04-08
- Estimated Expiration
- 2034-08-21
AI Technical Summary
Bridge pile foundations are prone to exposed tendons under the erosion of river silt, resulting in bare steel bars and accelerated corrosion, affecting the bearing capacity and stability of pile foundations, and thus endangering the safety of bridges.
The self-stressed pile foundation outer mold is set up on the upper part of the bridge pile foundation. The outer mold is composed of high-expanded concrete and external mold steel frame. The steel frame is composed of longitudinal bars and circumferential stirrups. Self-stress is formed by the expansion of the high-expanded concrete, which enhances the bending and tensile ability of the outer mold.
Through the setting of the self-stressed pile foundation external mold, the anti-shrinking ability of the bridge pile foundation is significantly improved, the bending and penetration resistance of the pile foundation is enhanced, the pile foundation is protected, and the safety of the bridge is ensured.
Smart Images
Figure CN222730595U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of bridges, and more specifically, to an anti-scouring pile foundation structure. Background Art
[0002] With the rapid development of social economy and urbanization, the road network has been gradually improved. The number of bridges built across rivers during road construction has also increased, resulting in an increasing number of bridges in rivers. During the service of bridge pile foundations, as river sediment washes the pile foundation, the concrete on the pile foundation will be exposed from the riverbed. Due to the construction process, the concrete pressure on the pile foundation is relatively small, resulting in generally low strength of the concrete on the pile foundation. After being washed away by river sediment over time, it is easy to expose the steel bars. The exposure of the pile foundation steel bars not only has an adverse effect on the bearing capacity and stability of the bridge pile foundation, but the corrosion of the exposed steel bars further accelerates the damage of the pile foundation, endangering the safety of the bridge.
[0003] To this end, the utility model proposes an anti-scour pile foundation structure which utilizes a self-stressed pile foundation outer mold to reinforce the upper part of the pile foundation. Summary of the invention
[0004] In order to overcome the disadvantages of the above technical problems, the utility model provides an anti-scouring pile foundation structure.
[0005] The utility model discloses an anti-scouring pile foundation structure, comprising a pile foundation and a bridge pier fixed on the pile foundation, wherein the pile foundation is cast in a river bed, and the upper part of the pile foundation is flush with the river scouring line; the utility model is characterized in that a self-stress pile foundation outer mold is arranged on the periphery of the upper part of the pile foundation, the self-stress pile foundation outer mold is a prefabricated part, the self-stress pile foundation outer mold is composed of high expansion concrete and an outer mold steel frame cast in the high expansion concrete, the outer mold steel frame is composed of outer mold longitudinal ribs and outer mold annular stirrups, the outer mold longitudinal ribs are evenly arranged in annular direction, and the outer mold annular stirrups are evenly fixed on the outer mold longitudinal ribs; the center of the self-stress pile foundation outer mold is a circular cavity for accommodating the upper part of the pile foundation.
[0006] The utility model discloses an anti-scouring pile foundation structure, wherein the pile foundation is composed of pile foundation concrete and a pile foundation steel bar skeleton cast in the pile foundation concrete, the pile foundation steel bar skeleton is composed of pile foundation longitudinal bars and pile foundation annular stirrups, the pile foundation longitudinal bars are evenly distributed in an annular direction, and the pile foundation annular stirrups are evenly fixed on the pile foundation longitudinal bars; the self-stressed pile foundation outer mold is arranged on the periphery of the upper part of the pile foundation steel bar skeleton and the pile foundation concrete is cast together.
[0007] In the utility model of the scour-resistant pile foundation structure, the outer diameter of the self-stress pile foundation outer mold is 0.5m-1.5m, and the wall thickness is 5.0cm-7.0cm.
[0008] The utility model provides an erosion-resistant pile foundation structure, wherein the outer mold longitudinal reinforcement and the outer mold annular stirrups are both made of cold-drawn low-carbon steel wire, the annular reinforcement ratio of the self-stressed pile foundation outer mold is 1.0%-1.8%, and the net protective layer thickness of the outer mold longitudinal reinforcement and the outer mold annular stirrups is 7mm-9mm.
[0009] In the scour-resistant pile foundation structure of the utility model, the high-expansion concrete of the self-stress pile foundation outer mold is high-expansion steel fiber concrete with a label of 40MPa-50MPa and a hoop self-stress value of 2.5MPa-4.5MPa.
[0010] The utility model has an anti-scouring pile foundation structure, wherein the outer form steel bar skeleton is formed by welding the outer form longitudinal bars and the outer form annular stirrups by a rolling welding machine, and the self-stressed pile foundation outer form is formed by the outer form steel bar skeleton and high expansion concrete by a rotating centrifuge.
[0011] The beneficial effects of the utility model are as follows: the scouring-resistant pile foundation structure of the utility model is provided with a self-stress pile foundation outer mold at a position corresponding to the river scouring line on the bridge pile foundation, the self-stress pile foundation outer mold is composed of an outer mold steel bar skeleton and high expansion concrete, and the outer mold steel bar skeleton is composed of an outer mold longitudinal ribs and an outer mold annular stirrups. In this way, after high expansion concrete is poured around the outer mold steel bar skeleton composed of the outer mold longitudinal ribs and the outer mold annular stirrups, longitudinal and annular self-stress is formed by the expansion of the high expansion concrete and the interaction between the outer mold longitudinal ribs and the outer mold annular stirrups. After the pile foundation and pier column concrete are poured as the pile foundation outer mold, it is no longer removed. The self-stress pile foundation outer mold is used as a protective layer of the bridge pile foundation. The self-stress pile foundation outer mold has good bending and tensile resistance. At the same time, the self-stress pile foundation outer mold is high expansion concrete. Due to the internal expansion of the concrete, the voids in the concrete are small, the strength is high, and the anti-seepage ability is strong, which greatly improves the ability of the bridge pile foundation to resist the impact of river water sediment. In this way, the influence of river water sediment under the bridge on the bridge pile foundation is solved and the safety of the bridge is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 It is a structural schematic diagram of the scour-resistant pile foundation structure of the utility model;
[0013] Figure 2 for Figure 1 Sectional view of section AA;
[0014] Figure 3 for Figure 1 Cross-sectional view of the middle BB section;
[0015] Figure 4 It is a structural schematic diagram of the outer formwork of the self-stressed pile foundation in the utility model.
[0016] In the figure: 1 pile foundation, 2 bridge pier, 3 riverbed, 4 self-stressed pile foundation outer formwork, 5 river scour line, 6 constant water level line, 7 pile foundation concrete, 8 pile foundation longitudinal reinforcement, 9 pile foundation annular stirrups, 10 high expansion concrete, 11 outer formwork longitudinal reinforcement, 12 outer formwork annular stirrups, 13 circular cavity. DETAILED DESCRIPTION
[0017] The utility model is further described below in conjunction with the accompanying drawings and embodiments.
[0018] like Figure 1 As shown, a schematic diagram of the structure of the scour-resistant pile foundation structure of the utility model is given. Figure 2 and Figure 3 They were given Figure 1 The sectional views of the AA and BB sections are shown in the figure. Figure 4 A structural schematic diagram of a self-stressed pile foundation outer formwork is provided. The anti-scouring pile foundation structure shown is composed of a pile foundation 1, a bridge pier 2 and a self-stressed pile foundation outer formwork 4. The pile foundation 1 is cast in the riverbed 3, and the bridge pier 2 is cast on the pile foundation 1. The pile foundation 1 supports the bridge pier 2. In the existing pouring process of the pile foundation 1, the concrete on the upper part of the pile foundation 1 is relatively small due to the influence of the pouring process of the pile foundation 1, which leads to the low strength of the concrete on the upper part of the pile foundation 1. Under the scouring action of the river water, the river scouring line 5 is located at the upper part of the pile foundation 1. In this way, under the impact of the silt and gravel carried by the river water, the concrete on the upper part of the pile foundation 1 is easily washed away, resulting in the exposure of the steel bars of the pile foundation 1, which reduces the bearing capacity and stability of the pile foundation 1, thereby endangering the safety of the bridge. The utility model proposes a technical solution of setting a self-stressed pile foundation outer formwork 4 on the periphery of the upper part of the pile foundation 1 to resist the impact of the silt and gravel carried by the river water on the pile foundation 1 and realize the protection of the pile foundation 1.
[0019] The self-stressed pile foundation outer formwork 4 is a prefabricated part in the shape of a cylindrical tube, which is composed of high expansion concrete 10 and an outer formwork steel reinforcement skeleton cast in the high expansion concrete 10. The outer formwork steel reinforcement skeleton is in the shape of a cylindrical steel cage. The outer formwork steel reinforcement skeleton is composed of outer formwork longitudinal ribs 11 and outer formwork annular stirrups 12. The outer formwork longitudinal ribs 11 are evenly distributed in the annular direction. The outer formwork annular stirrups 12 are evenly welded on the annular outer formwork longitudinal ribs 11 to form a stable outer formwork steel reinforcement skeleton. The high expansion concrete 10 is cast on the periphery of the outer formwork steel reinforcement skeleton formed by the outer formwork transverse ribs 11 and the outer formwork annular stirrups 12 to form a stable self-stressed pile foundation outer formwork 4.
[0020] The pile foundation 1 shown is composed of pile foundation concrete 7 and a pile foundation steel bar skeleton cast in the pile foundation concrete 7. The pile foundation steel bar skeleton is composed of pile foundation longitudinal ribs 8 and pile foundation annular stirrups 9. Similarly, the pile foundation longitudinal ribs 8 are evenly distributed in the annular direction, and the pile foundation annular stirrups 9 are evenly fixed on the pile foundation longitudinal ribs 8 to form a pile foundation steel bar skeleton in the shape of a cylindrical steel cage. The center of the self-stressed pile foundation outer mold 4 is a circular cavity 13, and the size of the circular cavity 13 should be sufficient to accommodate the passage of the pile foundation steel bar skeleton.
[0021] During construction, the prefabricated self-stressed pile foundation 4 is fixed to the periphery of the upper part of the pile foundation steel frame, and then the pile foundation concrete 7 is poured. After the pile foundation concrete 7 is poured, it forms the pile foundation 1 with the pile foundation longitudinal reinforcement 8 and the pile foundation annular stirrups 9, and the self-stressed pile foundation outer mold 4 is also fixed to the periphery of the upper part of the pile foundation 1.
[0022] Since the outer formwork of the self-stress pile foundation 4 is cast with high-expansion concrete 10, when the high-expansion concrete 10 expands, it interacts with the outer formwork longitudinal reinforcement 11 and the outer formwork annular stirrups 12 to form longitudinal and annular self-stress, so that the self-stress pile foundation outer formwork 4 has good bending and tensile resistance. At the same time, the self-stress pile foundation outer formwork 4 is high-expansion concrete. Due to the expansion of the concrete inside, the voids in the concrete are small, the strength is high, and the anti-seepage ability is strong, which greatly improves the ability of the bridge pile foundation to resist the impact of river mud and sand.
[0023] In order to ensure that the prefabricated self-stressed pile foundation outer formwork 4 has good stability, the outer formwork steel bar skeleton is welded by the outer formwork longitudinal reinforcement 11 and the outer formwork annular stirrups 12 through a rolling welding machine. After the outer formwork steel bar skeleton is welded, the outer formwork steel bar skeleton and the high expansion concrete 10 are formed into the self-stressed pile foundation outer formwork 4 through a rotating centrifuge.
[0024] As a specific requirement, the outer diameter of the self-stressed pile foundation outer formwork 4 is 0.5m~1.5m, and the wall thickness is 5.0cm~7.0cm. The outer formwork longitudinal reinforcement 11 and the outer formwork annular stirrups 12 are both made of cold-drawn low-carbon steel wire, the annular reinforcement ratio of the self-stressed pile foundation outer formwork 4 is 1.0%~1.8%, and the net protective layer thickness of the outer formwork longitudinal reinforcement 11 and the outer formwork annular stirrups 12 is 7mm~9mm. The high expansion concrete 10 of the self-stressed pile foundation outer formwork 4 is high expansion steel fiber concrete, the grade is 40MPa~50MPa, and the annular self-stress value is 2.5MPa~4.5MPa. Normally, the length of the pile foundation 1 is 20m~50m, and the length of the self-stressed pile foundation outer formwork 4 is 2m~5m.
[0025] The manufacturing process of the self-stressed pile foundation outer form 4 is as follows:
[0026] (1) Welding the outer mold frame: Use a roll welding machine to weld the outer mold longitudinal reinforcement 11 and the outer mold annular stirrups 12 to form an outer mold reinforcement frame;
[0027] (2) Casting: Place the outer formwork steel frame into the steel form, add high expansion concrete 10, and form it in a rotating centrifuge;
[0028] (3) Steaming: Steaming for 12-15 hours.
Claims
1. An anti-scour pile foundation structure, comprising a pile foundation (1) and a bridge pier (2) fixed on the pile foundation, wherein the pile foundation is cast in a river bed (3), and the upper part of the pile foundation is flush with a river scour line (5); characterized in that: A self-stressed pile foundation outer mold (4) is arranged on the periphery of the upper part of the pile foundation. The self-stressed pile foundation outer mold is a prefabricated part. The self-stressed pile foundation outer mold is composed of high expansion concrete (10) and an outer mold steel reinforcement skeleton cast in the high expansion concrete. The outer mold steel reinforcement skeleton is composed of outer mold longitudinal reinforcement (11) and outer mold annular stirrups (12). The outer mold longitudinal reinforcement is evenly arranged in an annular direction. The outer mold annular stirrups are evenly fixed on the outer mold longitudinal reinforcement. The center of the self-stressed pile foundation outer mold is a circular cavity (13) for accommodating the upper part of the pile foundation.
2. The scour-resistant pile foundation structure according to claim 1, characterized in that: The pile foundation (1) is composed of pile foundation concrete (7) and a pile foundation steel reinforcement skeleton cast in the pile foundation concrete, the pile foundation steel reinforcement skeleton is composed of pile foundation longitudinal reinforcement (8) and pile foundation annular stirrups (9), the pile foundation longitudinal reinforcement is evenly distributed in an annular direction, and the pile foundation annular stirrups are evenly fixed on the pile foundation longitudinal reinforcement; the self-stressed pile foundation outer mold (4) is arranged on the periphery of the upper part of the pile foundation steel reinforcement skeleton and is cast together with the pile foundation concrete (7).
3. The scour-resistant pile foundation structure according to claim 1 or 2, characterized in that: The outer diameter of the self-stressed pile foundation outer formwork (4) is 0.5 m to 1.5 m, and the wall thickness is 5.0 cm to 7.0 cm.
4. The scour-resistant pile foundation structure according to claim 1 or 2, characterized in that: The outer mold longitudinal reinforcement (11) and the outer mold annular stirrups (12) are both made of cold-drawn low-carbon steel wire, the annular reinforcement ratio of the self-stressed pile foundation outer mold is 1.0% to 1.8%, and the net protective layer thickness of the outer mold longitudinal reinforcement and the outer mold annular stirrups is 7 mm to 9 mm.
5. The scour-resistant pile foundation structure according to claim 1 or 2, characterized in that: The high expansion concrete (10) of the self-stressed pile foundation outer formwork (4) is a high expansion steel fiber concrete with a grade of 40MPa-50MPa and a hoop self-stress value of 2.5MPa-4.5MPa.
6. The scour-resistant pile foundation structure according to claim 1 or 2, characterized in that: The outer formwork steel reinforcement skeleton is formed by welding the outer formwork longitudinal reinforcement (11) and the outer formwork annular stirrups (12) by a rolling welding machine, and the self-stressed pile foundation outer formwork is formed by the outer formwork steel reinforcement skeleton and the high expansion concrete (10) by a rotating centrifuge.