Prefabricated tubular pile for pile-slab structure in high seismic intensity area
By setting longitudinal prestressed steel bars and longitudinal ordinary steel bars in prefabricated pipe piles and optimizing their cross-sectional reinforcement rate and tension force, the problem of insufficient bending load-bearing capacity in high seismic intensity areas is solved, and higher bending load-bearing capacity and more economical construction plans are achieved.
Patent Information
- Application Number
- CN202421824236.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-31
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2034-07-31
AI Technical Summary
The existing prefabricated pipe piles have insufficient bending load-bearing capacity in high seismic intensity areas, which is difficult to meet the application needs of pile plate structures in high seismic intensity areas.
The concrete pile body with an annular structure is equipped with longitudinal prestressed steel bars and longitudinal ordinary steel bars. By scientifically configuring the cross-sectional reinforcement ratio and tensioning force of longitudinal prestressed steel bars and longitudinal ordinary steel bars, the bending load bearing capacity of the pipe piles is improved.
Without increasing the rigidity of pipe piles and increasing the construction difficulty, the bending load-bearing capacity of prefabricated pipe piles is significantly improved, and the applicability and economicality of pile plate structures in high seismic intensity areas are enhanced.
Smart Images
Figure CN222822247U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of pile-plate structure design and construction, in particular to a prefabricated pipe pile for a pile-plate structure in a high seismic intensity area. Background Art
[0002] In recent years, with the large-scale construction of expressways and increasingly stringent land security and environmental protection requirements, the constraints on expressway construction in plain areas due to factors such as difficulty in land acquisition and shortage of soil sources have become increasingly obvious. The traditional roadbed solution not only occupies precious land resources, but also requires a large amount of roadbed fill. If the traditional roadbed solution is changed to a bridge solution, it will lead to a large amount of construction materials and high construction costs. In addition, a large amount of reinforced concrete will increase CO2 emissions, which is not in line with the development concept of green highways.
[0003] The pile-slab structure is a fully assembled structure, with prefabricated beams and slabs for the upper structure and prefabricated pipe piles for the lower structure. The beams and slabs and the pipe piles are generally connected by piers and beams. Compared with the earth-fill roadbed solution, the pile-slab structure "replaces the road with a bridge", which reduces the project area, reduces the backfill, and saves precious land resources. Compared with the bridge solution, the pile-slab structure uses less materials, and its advantages as a fully assembled structure greatly shorten the construction period, which not only reduces the project cost and construction period, but also has a higher degree of standardization, is more efficient and environmentally friendly, and is more in line with the development concept of green highways.
[0004] However, the existing prefabricated pipe piles are generally only suitable for low-cap vertical foundation piles in areas with seismic fortification intensity of 8 degrees or less. They are mainly used to withstand axial pressure and can only withstand small bending moments. When the pile-plate structure is located in a high seismic intensity area, its prefabricated pipe pile columns need to withstand large bending moments under the action of earthquakes. The stress performance of the existing prefabricated pipe piles is difficult to meet the requirements, which greatly limits the application of pile-plate structures in high seismic intensity areas.
[0005] When the bending bearing capacity of prefabricated pipe piles cannot meet the requirements, the bending bearing capacity of the pipe piles is generally improved by increasing the pile diameter, or by setting an internal partition in the pipe pile and casting reinforced concrete above the partition to form a solid pile.
[0006] However, the pile-slab structure is a multi-span rigid frame system with piers and beams. When the pile diameter is increased, the rigidity of its lower structure also increases. Under the same seismic load, the bending moment that the pile needs to bear also increases. Therefore, the effect of increasing the pile diameter to improve the stress performance of prefabricated pipe piles under earthquakes is limited and has poor economic efficiency. As for the method of forming solid piles by setting internal partitions in the pipe piles and casting reinforced concrete above the partitions, its construction process is relatively complicated, which also increases the rigidity of the pipe piles, and is contrary to the industrialized idea of factory prefabrication and assembly construction of prefabricated pipe piles. Summary of the invention
[0007] The utility model provides a prefabricated pipe pile for pile-plate structure in high seismic intensity areas without increasing the rigidity of the pipe pile and the difficulty of construction. The specific technical scheme is as follows:
[0008] The prefabricated pipe pile for pile-plate structure in high seismic intensity area described in the utility model comprises a concrete pile body with an annular structure, wherein longitudinal prestressed steel bars and longitudinal ordinary steel bars are arranged in the concrete pile body, wherein the longitudinal prestressed steel bars are evenly spaced and arranged on one of the concentric circles of the concrete pile body, wherein the longitudinal ordinary steel bars are located on the same side of the longitudinal prestressed steel bars and are arranged in parallel with each longitudinal prestressed steel bar or are arranged in groups of two between two adjacent longitudinal prestressed steel bars, and longitudinal spiral stirrups connected to the longitudinal prestressed steel bars and the longitudinal ordinary steel bars are arranged on the outer sides thereof.
[0009] The concrete pile body is made of high-strength concrete or ultra-high performance concrete with a grade of C80 or above, and its outer diameter does not exceed 600mm.
[0010] The longitudinal prestressed steel bars are prestressed steel bars with a strength grade of PCB1570 or prestressed steel strands with a strength grade of 1720 and above. The tension applied to the longitudinal prestressed steel bars is 50-90% of the normal value, and the cross-sectional reinforcement ratio of the longitudinal prestressed steel bars is 110-150% of that of ordinary pipe piles.
[0011] The longitudinal common steel bars are hot-rolled ribbed steel bars with a strength grade of HRB500 or HRB600, or prestressed threaded steel bars with a strength grade of PSB785 or above, and the cross-sectional reinforcement ratio of the longitudinal common steel bars is 110-160% of that of common pipe piles.
[0012] The longitudinal spiral stirrups are made of cold-drawn low-carbon steel wire with a strength grade of CDW550 or hot-rolled ribbed steel bars with a strength grade of HRB400 and above.
[0013] The above-mentioned improved prefabricated pipe piles proposed in the utility model have the advantages of high degree of prefabrication, good force-bearing performance, economical cost, convenient construction, etc., especially greatly improving the bending moment bearing capacity of the prefabricated pipe piles, thereby improving the applicability of the pile-plate structure in high seismic intensity areas and expanding the application scope of the pile-plate structure. The improved prefabricated pipe piles proposed in the utility model are also suitable for other application scenarios that need to withstand large horizontal forces. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural schematic diagram of the prefabricated pipe piles described in Example 1.
[0015] Figure 2 It is a schematic diagram of the structure of the prefabricated pipe piles described in Example 2. DETAILED DESCRIPTION
[0016] The following is a detailed description of an embodiment of the utility model in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the utility model, and a detailed implementation method and a specific construction process are given, but the protection scope of the utility model is not limited to the following embodiment.
[0017] Embodiment 1:
[0018] like Figure 1 As shown, the prefabricated pipe pile for pile-slab structure in high seismic intensity area described in the utility model comprises a concrete pile body 1 of annular structure, longitudinal prestressed steel bars 2 and longitudinal common steel bars 3 are arranged in the concrete pile body 1, the longitudinal prestressed steel bars 2 are evenly spaced on one of the concentric circles of the concrete pile body, a group of longitudinal common steel bars 3 is arranged between two adjacent longitudinal prestressed steel bars 2, and the longitudinal common steel bars 3 in the same group are two, and the two are arranged in parallel. The outer sides of the longitudinal prestressed steel bars 2 and the longitudinal common steel bars 3 are welded and connected with a longitudinal spiral stirrup 4.
[0019] In this embodiment, the concrete pile body 1 is made of C80 high-strength concrete, with an outer diameter of 500mm and a wall thickness of 100mm. The longitudinal prestressed steel bar 2 is a prestressed steel bar with a diameter of 14mm and a strength grade of PCB1570, and its tension force is 0.6fpk=942MPa; the longitudinal ordinary steel bar 3 is a hot-rolled ribbed steel bar with a diameter of 12mm and a strength grade of HRB500. Among them, there are 12 longitudinal prestressed steel bars 2 and 24 longitudinal ordinary steel bars 3. According to the "Pre-tensioning Prestressed Concrete Pipe Piles Atlas" (23G409), the steel bar area of the longitudinal prestressed steel bar 2 in this embodiment is increased by 154mm 2 , the area of longitudinal ordinary steel bar 3 steel bar increased by 502mm 2, that is, the cross-sectional reinforcement ratio of the longitudinal prestressed steel bar 2 is 110% of that of the ordinary pipe pile, and the cross-sectional reinforcement ratio of the longitudinal ordinary steel bar 3 is 123% of that of the ordinary pipe pile. The tension force of the longitudinal prestressed steel bar 2 is 86% of that of the ordinary pipe pile. The spiral stirrup 4 is made of cold-drawn low-carbon steel wire with a diameter of 5mm and a strength grade of CDW550.
[0020] According to tests, the maximum bending bearing capacity of the prefabricated pipe piles described in this embodiment can be increased by about 38% compared with the pipe piles of the same size in the "Atlas of Prestressed Concrete Pipe Piles" (23G409).
[0021] Embodiment 2:
[0022] like Figure 2 As shown, the prefabricated pipe pile for pile-plate structure in high seismic intensity area described in the utility model comprises a concrete pile body 1 of annular structure, longitudinal prestressed steel bars 2 and longitudinal ordinary steel bars 3 are arranged in the concrete pile body 1, the longitudinal prestressed steel bars 2 are evenly spaced on one of the concentric circles of the concrete pile body, a longitudinal ordinary steel bar 3 is arranged on the same side of each longitudinal prestressed steel bar 2, the two are arranged in parallel, and the outer sides of the longitudinal prestressed steel bars 2 and the longitudinal ordinary steel bars 3 are welded and connected with a longitudinal spiral stirrup 4.
[0023] In this embodiment, the concrete pile body 1 is made of C80 high-strength concrete, with an outer diameter of 600mm and a wall thickness of 110mm. The longitudinal prestressed steel bar 2 is a prestressed steel bar with a diameter of 14mm and a strength grade of PCB1570, and its tension force is 0.5fpk=785MPa; the longitudinal ordinary steel bar 3 is a hot-rolled ribbed steel bar with a diameter of 16mm and a strength grade of HRB600. There are 18 longitudinal prestressed steel bars 2 and longitudinal ordinary steel bars 3, which are divided into 18 groups and evenly distributed in a circular shape. The longitudinal prestressed steel bars 2 and longitudinal ordinary steel bars 3 of each group are arranged in parallel, and the arrangement order of the longitudinal prestressed steel bars 2 and longitudinal ordinary steel bars 3 of each group is consistent. According to the "Pre-tensioning Prestressed Concrete Pipe Piles Atlas" (23G409), the steel bar area of the longitudinal prestressed steel bar 2 in this embodiment is increased by 462mm 2 , the area of longitudinal ordinary steel bar 3 steel bar increased by 603mm 2 , that is, the cross-sectional reinforcement ratio of the longitudinal prestressed steel bar 2 is 120% of that of the ordinary pipe pile, and the cross-sectional reinforcement ratio of the longitudinal ordinary steel bar 3 is 120% of that of the ordinary pipe pile. The tension force of the longitudinal prestressed steel bar 2 is 71% of that of the ordinary pipe pile. The spiral stirrup 4 is made of cold-drawn low-carbon steel wire with a diameter of 5mm and a strength grade of CDW550.
[0024] According to tests, the maximum bending bearing capacity of the prefabricated pipe piles described in this embodiment can be increased by about 27% compared with the pipe piles of the same size in the "Atlas of Prestressed Concrete Pipe Piles" (23G409).
[0025] Embodiment 3:
[0026] The prefabricated pipe pile structure for pile-slab structure in high seismic intensity area described in this embodiment is the same as the prefabricated pipe pile structure of embodiment 2, except that: the concrete pile body 1 is made of C80 high-strength concrete, with an outer diameter of 600mm and a wall thickness of 110mm. The longitudinal prestressed steel bar 2 adopts a prestressed steel strand with a diameter of 15.2mm and a strength grade of 1860, and its tension is 0.5fpk=930MPa; the longitudinal common steel bar 3 adopts a prestressed threaded steel bar with a diameter of 15mm and a strength grade of PSB930. There are 16 longitudinal prestressed steel bars 2 and longitudinal common steel bars 3. According to the Atlas of Prestressed Concrete Pipe Piles (23G409), the cross-sectional reinforcement ratio of the longitudinal prestressed steel bars 2 and the longitudinal common steel bars 3 in this embodiment is equivalent to that of ordinary pipe piles, the longitudinal prestressed steel bars 2 use prestressed steel strands instead of prestressed steel bars, and the longitudinal common steel bars 3 use prestressed threaded steel bars instead of hot-rolled ribbed steel bars, wherein the tension of the longitudinal prestressed steel bars 2 is 67% of the conventional value. The spiral stirrups 4 are made of hot-rolled ribbed steel bars with a diameter of 6 mm and a strength grade of HRB500.
[0027] According to tests, the maximum bending bearing capacity of the prefabricated pipe piles described in this embodiment can be increased by about 49% compared with the pipe piles of the same size in the "Atlas of Prestressed Concrete Pipe Piles" (23G409).
[0028] It can be seen that the prefabricated pipe piles described in the utility model can improve the seismic and bending bearing capacity of the prefabricated pipe piles without increasing the pile diameter by reducing the tensioning force of the longitudinal prestressed steel bars, improving the strength and cross-sectional reinforcement ratio of the longitudinal prestressed steel bars and the longitudinal ordinary steel bars, and scientifically configuring the longitudinal prestressed steel bars and the longitudinal ordinary steel bars, thereby making the pile-plate structure more economical and reasonable in high seismic intensity areas.
[0029] It should be noted that, in the description of the present invention, terms indicating orientation or positional relationships, such as "front", "rear", "left", "right", "vertical", "horizontal", "inside", "outside", etc., are based on the orientation or positional relationships shown in the drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
Claims
1. A prefabricated pipe pile for pile-plate structure in high seismic intensity areas, characterized by: A concrete pile body comprising an annular structure is provided in the concrete pile body, wherein longitudinal prestressed steel bars and longitudinal common steel bars are arranged in the concrete pile body, wherein the longitudinal prestressed steel bars are evenly spaced and arranged on one of the concentric circles of the concrete pile body, wherein the longitudinal common steel bars are located on the same side of the longitudinal prestressed steel bars and are arranged in parallel with each longitudinal prestressed steel bar or are arranged in groups of two between two adjacent longitudinal prestressed steel bars, and longitudinal spiral stirrups connected to the longitudinal prestressed steel bars and the longitudinal common steel bars are arranged on the outer sides thereof.
2. The prefabricated pipe pile for pile-plate structure in high seismic intensity area according to claim 1, characterized in that: The concrete pile body is made of high-strength concrete or ultra-high performance concrete with a grade of C80 or above, and its outer diameter does not exceed 600mm.
3. The prefabricated pipe pile for pile-plate structure in high seismic intensity area according to claim 1, characterized in that: The longitudinal prestressed steel bars are prestressed steel bars with a strength grade of PCB1570 or prestressed steel strands with a strength grade of 1720 and above. The tension applied to the longitudinal prestressed steel bars is 50-90% of the normal value, and the cross-sectional reinforcement ratio of the longitudinal prestressed steel bars is 110-150% of that of ordinary pipe piles.
4. The prefabricated pipe pile for pile-plate structure in high seismic intensity area according to claim 1, characterized in that: The longitudinal common steel bars are hot-rolled ribbed steel bars with a strength grade of HRB500 or HRB600, or prestressed threaded steel bars with a strength grade of PSB785 or above, and the cross-sectional reinforcement ratio of the longitudinal common steel bars is 110-160% of that of common pipe piles.
5. The prefabricated pipe pile for pile-plate structure in high seismic intensity area according to claim 1, characterized in that: The longitudinal spiral stirrups are made of cold-drawn low-carbon steel wire with a strength grade of CDW550 or hot-rolled ribbed steel bars with a strength grade of HRB400 and above.