Variable cross-section pile foundation
By optimizing the reinforcement structure of the variable cross-section pile foundation and adopting a closed-loop structure, the problems of complex reinforcement and high stress in the existing technology are solved, thereby improving the stability of the pile foundation and the efficiency of material utilization.
Patent Information
- Application Number
- CN202423265559.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2034-12-30
AI Technical Summary
Existing variable cross-section pile foundations have complex reinforcement structures and high stress in the steel cages, resulting in material waste and difficulty in meeting the horizontal displacement requirements of bored foundations on steep slopes.
A novel reinforcement method is adopted, including a closed-loop structure composed of main pile reinforcement, main reinforcement stirrups, anchor bolts and longitudinal reinforcement. By optimizing the reinforcement design of the pile foundation, the stress of the steel cage is reduced and the length of the variable cross-section pile is shortened.
It achieves a balance between the stability and stress level of the pile foundation, reduces the stress on the steel cage, reduces material waste, and meets the design requirements of bored foundations for steep slopes.
Smart Images
Figure CN223793616U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of variable cross-section pile foundation technology, and in particular to a variable cross-section pile foundation. Background Technology
[0002] When designing bored foundations for steep slopes, the horizontal displacement of the ground surface where the piles are located is not easily satisfied. This can be addressed by increasing the upper cross-section of the foundation to meet relevant regulations. For large-diameter steel pipe pile foundations, the pile diameter is controlled by the bottom diameter of the steel pipe. Due to the relatively small foundation force, using constant cross-section piles would result in material waste; therefore, variable cross-section pile foundations can be used. However, existing variable cross-section pile foundations have complex reinforcement structures and high stress in the steel cage. Utility Model Content
[0003] This utility model proposes a variable cross-section pile foundation.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] A variable cross-section pile foundation includes a pile cap, under which cast-in-place piles are provided. The diameter of the cast-in-place piles is smaller than the diameter of the pile cap. Circularly distributed main reinforcement bars are provided within the cast-in-place piles. Stirrups are fixed to both sides of the main reinforcement bars. The main reinforcement bars extend into the pile cap. Circularly distributed large-diameter longitudinal reinforcement bars are provided within the pile cap. The large-diameter longitudinal reinforcement bars are fixedly connected to the large-diameter stirrups. Circularly distributed anchor bolts are also provided within the pile cap. The diameter D1 of the circularly distributed anchor bolts is smaller than the diameter D2 of the circularly distributed large-diameter longitudinal reinforcement bars, and the diameter D1 of the circularly distributed anchor bolts is larger than the diameter D3 of the circularly distributed main reinforcement bars.
[0006] Furthermore, several straight stirrups are fixed between the large-diameter stirrups and the main reinforcement of the pile.
[0007] Furthermore, large-diameter stirrups are fixed to the outside of the large-diameter longitudinal reinforcement.
[0008] Furthermore, anchor bolts are provided on both sides, and the anchor bolts include outer anchor bolts and inner anchor bolts. The outer anchor bolts are fixed to the outside of the anchor bolts, and the inner anchor bolts are fixed to the inside of the anchor bolts.
[0009] Furthermore, the top surface of the foundation is provided with a number of upper horizontal ribs and upper vertical ribs, the upper horizontal ribs are arranged in parallel, the upper vertical ribs are arranged in parallel, and the upper vertical ribs are arranged perpendicular to the upper horizontal ribs.
[0010] Furthermore, the bottom surface of the foundation is provided with lower horizontal ribs and lower vertical ribs, the lower horizontal ribs are arranged in parallel, the lower vertical ribs are arranged in parallel, and the lower vertical ribs are arranged perpendicular to the lower horizontal ribs.
[0011] Furthermore, the foundation is provided with several small longitudinal ribs, which are arranged parallel to the large-diameter longitudinal ribs.
[0012] Furthermore, the section of the main reinforcement bar of the pile that extends into the pile cap is a connecting section, and the angle between the connecting section and the vertical plane is α.
[0013] Furthermore, from bottom to top, the connecting sections are fixed with pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8. Each of the pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8 is formed by welding the ends of steel bars into a closed circle. The diameters of the pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8 increase sequentially.
[0014] Furthermore, the main reinforcement stirrups include spiral stirrups and stiffening stirrups, with spiral stirrups fixed to the outer side of the main reinforcement of the pile and stiffening stirrups fixed to the inner side of the main reinforcement of the pile.
[0015] Furthermore, the stiffening stirrups are provided at 2000mm intervals in the vertical direction.
[0016] Advantages: This utility model adopts a new reinforcement method, which can shorten the length of the large diameter part of the variable cross-section pile, while the stress level of the pile can still remain stable, and the stress of the steel cage is reduced. Attached Figure Description
[0017] Figure 1 This is a top view schematic diagram of the reinforcement structure of this utility model;
[0018] Figure 2 This is a front view of the present invention after casting;
[0019] Figure 3 This is a schematic diagram of the reinforcement design for the cast-in-place pile of this utility model;
[0020] Figure 4 This is a schematic diagram of the distribution structure of the main reinforcement bars in the central pile of this utility model;
[0021] Figure 5 This is a schematic diagram showing the distribution of the pads in this utility model;
[0022] Figure 6 This is a top view of the pad block in this utility model;
[0023] Figure 7 This is a front view of the pad block in this utility model;
[0024] Figure 8This is a schematic diagram of the reinforcement details on the top and bottom surfaces of the foundation in this utility model.
[0025] Figure 9 This is a schematic diagram of the reinforcement details in the main view of the foundation of this utility model.
[0026] Figure 10 This is a schematic diagram showing the distribution of large-diameter longitudinal ribs in this utility model;
[0027] Figure 11 This is a schematic diagram showing the distribution of anchor bolts in this utility model;
[0028] Figure 12 This is a top view of the positioning template in this utility model;
[0029] Figure 13 This is a top view of the fastening template in this utility model.
[0030] In the diagram: 1. Foundation, 2. Cast-in-place pile, 3. Subbase, 4. Ground bolt cap;
[0031] 101 Top horizontal reinforcement, 102 Top longitudinal reinforcement, 103 Bottom horizontal reinforcement, 104 Bottom longitudinal reinforcement, 105 Small longitudinal reinforcement, 106 Large diameter longitudinal reinforcement, 107 Large diameter external stirrup, 108 Large diameter internal stirrup, 109 Anchor bolt, 110 Ground bolt stirrup, 111 Large diameter stirrup, 112 Straight stirrup, 11 Positioning template, 1101 Annular plate one, 1102 Circular hole one, 12 Fastening template, 1201 Annular plate two, 1202 Circular hole two;
[0032] 201 Main reinforcement bar of pile, 202 Spiral stirrup, 203 Stiffening stirrup, 204 External stirrup 1 of pile, 205 External stirrup 2 of pile, 206 External stirrup 3 of pile, 207 External stirrup 4 of pile, 208 External stirrup 5 of pile, 209 External stirrup 6 of pile, 210 External stirrup 7 of pile, 211 External stirrup 8 of pile, 212 Spacer block, 21201 Body 1, 21202 Installation hole 1. Detailed Implementation
[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.
[0034] 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.
[0035] Reference Figure 1-13 A variable cross-section pile foundation includes a pile cap 1, under which cast-in-place piles 2 are provided. The diameter of the cast-in-place piles 2 is smaller than the diameter of the pile cap 1. The cast-in-place piles 2 contain circularly distributed main reinforcement bars 201, which are HRB400 grade. The circular distribution is such that, from a top view of the cast-in-place piles 2, the main reinforcement bars 201 are arranged in a uniformly circular array. Stirrups of HPB300 grade are fixed on both sides of each main reinforcement bar 201. The main reinforcement bars 201 extend into the pile cap 1. Large-diameter longitudinal reinforcement bars 106 are also arranged in a circular distribution within the pile cap 1. From a viewing angle, the large-diameter longitudinal reinforcement 106 is arranged in a circular array at equal angles. The large-diameter longitudinal reinforcement 106 is fixedly connected to the large-diameter stirrups 111. The pile cap 1 also has circularly distributed anchor bolts 109. This circular distribution, viewed from above, is a circular array of anchor bolts at equal angles. The diameter D1 of the circular distribution of the anchor bolts 109 is smaller than the diameter D2 of the circular distribution of the large-diameter longitudinal reinforcement 106, and larger than the diameter D3 of the circular distribution of the main pile reinforcement 201. Both the cast-in-place pile 2 and the pile cap 1 are constructed of cast concrete. The length H1 of the pile cap is greater than or equal to half the diameter D1 of the pile cap. The diameter D2 of the cast-in-place pile is greater than or equal to half the diameter D1 of the pile cap.
[0036] This utility model provides an embodiment in which the top of the cast-in-place pile 2 is embedded in the pile cap 1, and the embedded portion of the cast-in-place pile 2 in the pile cap 1 is 100mm. A ground bolt cap 4 is provided on the top of the pile cap 1. A cushion layer 3 is provided between the lower part of the pile cap 1 and the cast-in-place pile 2.
[0037] This utility model provides an embodiment, with reference to... Figure 1 Several straight stirrups 112 are fixed between the large-diameter stirrups 111 and the main pile reinforcement 201. The straight stirrups 112 are distributed in a circular pattern at equal angles between the large-diameter stirrups 111 and the main pile reinforcement 201.
[0038] This utility model provides an embodiment in which a large-diameter stirrup 111 is fixed on the outside of the large-diameter longitudinal reinforcement 106.
[0039] This utility model provides an embodiment, with reference to... Figure 10 The large-diameter stirrups 111 include large-diameter outer stirrups 107 and large-diameter inner stirrups 108. Large-diameter outer stirrups 107 are fixed to the outer side of the large-diameter longitudinal reinforcement 106, and large-diameter inner stirrups 108 are fixed to the inner side of the large-diameter longitudinal reinforcement 106. Both the large-diameter outer stirrups 107 and the large-diameter inner stirrups 108 are formed by welding the ends of reinforcing bars into a closed circle. The diameter of the large-diameter outer stirrup 107 is larger than the diameter of the large-diameter inner stirrup 108.
[0040] This utility model provides an embodiment, with reference to... Figure 11 The anchor bolt 109 is provided with a ground bolt stirrup 110 on its outer side.
[0041] This utility model provides an embodiment, with reference to... Figure 1 The anchor bolt 109 is provided with anchor bolt stirrups 110 on both sides. Each stirrup 110 includes an outer stirrup and an inner stirrup. The outer stirrup is fixed to the outside of the anchor bolt 109, and the inner stirrup is fixed to the inside of the anchor bolt 109. Both the outer and inner stirrups are formed by welding steel bars to form a closed circle. The diameter of the outer stirrup is larger than the diameter of the inner stirrup.
[0042] This utility model provides an embodiment, with reference to... Figure 8-9 The top surface of the foundation 1 is provided with a plurality of upper horizontal ribs 101 and upper vertical ribs 102. The upper horizontal ribs 101 are arranged in parallel, the upper vertical ribs 102 are arranged in parallel, and the upper vertical ribs 102 are arranged perpendicular to the upper horizontal ribs 101. The bottom surface of the foundation 1 is provided with lower horizontal ribs 103 and lower vertical ribs 104. The lower horizontal ribs 103 are arranged in parallel, the lower vertical ribs 104 are arranged in parallel, and the lower vertical ribs 104 are arranged perpendicular to the lower horizontal ribs 103.
[0043] This utility model provides an embodiment, with reference to... Figure 8 The foundation 1 is provided with a number of small longitudinal ribs 105, which are arranged parallel to the large-diameter longitudinal ribs 106. The length of the small longitudinal ribs 105 is greater than the thickness of the foundation 1.
[0044] This utility model provides an embodiment, with reference to... Figure 12 The anchor bolt 109 is positioned inside the positioning template 11. The positioning template 11 includes an annular plate 1101, which has several circular holes 1102, and an anchor bolt 109 is installed in each circular hole 1102.
[0045] This utility model provides an embodiment, with reference to... Figure 13 The anchor bolt 109 is disposed on its lower side within the fastening template 12. The fastening template 12 includes an annular plate 1201, which has a plurality of circular holes 1202, and an anchor bolt 109 is disposed in each circular hole 1202.
[0046] This utility model provides an embodiment, with reference to... Figure 3The section of the main reinforcement bar 201 extending into the pile cap 1 is a connecting section, and the angle between the connecting section and the vertical plane is α. The connecting sections are fixed with pile outer stirrups 1 (204), 2 (205), 3 (206), 4 (207), 5 (208), 6 (209), 7 (210), and 8 (211) sequentially from bottom to top. Each of the pile outer stirrups 1 (204), 2 (205), 3 (206), 4 (207), 5 (208), 6 (209), 7 (210), and 8 (211) is formed by welding the ends of steel bars into a closed circle. The diameter of each pile outer stirrup increases sequentially.
[0047] This utility model provides an embodiment, with reference to... Figure 1 The main reinforcement stirrups include spiral stirrups 202 and stiffening stirrups 203. Spiral stirrups are fixed to the outer side of the main reinforcement 201, and stiffening stirrups 203 are fixed to the inner side of the main reinforcement 201. The stiffening stirrups 203 are formed by welding the ends of the reinforcing bars into a closed circle. The stiffening stirrups 203 located at the top and bottom of the cast-in-place pile 2 are welded to the main reinforcement 201, while the stiffening stirrups 203 located in the middle are tied to the main reinforcement 201. One stiffening stirrup 203 is provided every 2000mm in the vertical direction.
[0048] This utility model provides an embodiment, with reference to... Figure 5 Connecting reinforcing bars are fixed to the outer sides of the main reinforcing bars 201 of two adjacent piles, and spacers 212 are installed on the connecting reinforcing bars. (Refer to...) Figure 6-7 The pad 212 includes a body 21201, which is disc-shaped. A mounting hole 21202 is provided at the center of the body 21201, through which the connecting steel bar passes. (Refer to...) Figure 3 In the vertical direction of the cast-in-place pile 2, a set of pad blocks 212 is set every 2000mm. Each set of pad blocks 212 includes four pad blocks 212. The four pad blocks 212 are set at a height of [reference missing]. Figure 5 Furthermore, the four pads 212 are set at equal angles.
[0049] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A variable cross-section pile foundation, comprising a pile cap, wherein cast-in-place piles are disposed beneath the pile cap, the diameter of the cast-in-place piles being smaller than the diameter of the pile cap, characterized in that: The cast-in-place pile is provided with main reinforcement bars distributed in a circle. Stirrups are fixed on both sides of the main reinforcement bars. The main reinforcement bars extend into the pile cap. Large-diameter longitudinal reinforcement bars are provided in a circle in the pile cap. The large-diameter longitudinal reinforcement bars are fixedly connected to the large-diameter stirrups. Anchor bolts are also provided in a circle in the pile cap. The diameter D1 of the circle of the anchor bolts is smaller than the diameter D2 of the circle of the large-diameter longitudinal reinforcement bars. The diameter D1 of the circle of the anchor bolts is larger than the diameter D3 of the circle of the main reinforcement bars.
2. A variable cross-section pile foundation according to claim 1, characterized in that: Several straight stirrups are fixed between the large-diameter stirrups and the main reinforcement of the pile.
3. A variable cross-section pile foundation according to claim 1, characterized in that: Large-diameter stirrups are fixed to the outside of the large-diameter longitudinal bars.
4. A variable cross-section pile foundation according to claim 1, characterized in that: The anchor bolt is provided with anchor bolt stirrups on both sides. The anchor bolt stirrups include an outer anchor bolt stirrup and an inner anchor bolt stirrup. The outer anchor bolt stirrup is fixed to the outside of the anchor bolt, and the inner anchor bolt stirrup is fixed to the inside of the anchor bolt.
5. A variable cross-section pile foundation according to claim 1, characterized in that: The foundation is provided with several small longitudinal ribs, which are arranged parallel to the large-diameter longitudinal ribs.
6. A variable cross-section pile foundation according to claim 1, characterized in that: The section of the main reinforcement bar of the pile that extends into the pile cap is called the connecting section, and the angle between the connecting section and the vertical plane is α.
7. A variable cross-section pile foundation according to claim 6, characterized in that: The connecting sections are fixed with pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8 in sequence from bottom to top. All pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8 are made by welding the ends of steel bars into a closed circle. The diameter of pile outer stirrups 1, 2, 3, 4, 5, 6, 7, and 8 increases sequentially.
8. A variable cross-section pile foundation according to claim 1, characterized in that: The main reinforcement stirrups include spiral stirrups and stiffening stirrups. Spiral stirrups are fixed on the outer side of the main reinforcement of the pile, and stiffening stirrups are fixed on the inner side of the main reinforcement of the pile.
9. A variable cross-section pile foundation according to claim 8, characterized in that: The stiffening stirrups are installed at 2000mm intervals in the vertical direction.