A pile cap, a pile and a foundation
By designing stepped pile caps and geogrid structures, the problem of singular interaction between pile caps and backfill soil was solved, achieving efficient hierarchical load transfer and improving the bearing capacity of the foundation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGZHOU DESIGN INST
- Filing Date
- 2025-07-21
- Publication Date
- 2026-07-31
AI Technical Summary
The interaction between the existing pile cap and the backfill is relatively simple, resulting in low load transfer efficiency. The synergistic bearing capacity of the pile body and the soil between the piles has not been effectively utilized, thus limiting the overall bearing capacity of the composite foundation.
Design a pile cap including a cap body, a first protrusion and a second protrusion, forming a stepped structure. The first protrusion is higher than the second protrusion and closer to the axis of the cap body. Multiple steps form independent soil arch support points in the fill. The load is transferred in layers through the local superposition of soil arches. The stability of the soil arch is enhanced by combining geogrid.
It improves load transfer efficiency, enhances the bearing capacity and stability of the foundation, and transfers loads in layers through multiple soil arching effects, avoiding load concentration and improving the overall bearing performance of the composite foundation.
Smart Images
Figure CN224578726U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of construction engineering, in particular to a pile cap, a pile column and a foundation. Background Art
[0002] At present, in the field of construction engineering, a composite foundation bears the load of the superstructure through the cooperative action of pile bodies and the soil between piles, and its bearing capacity directly affects the safety and stability of the project. Among them, the load transfer path of the composite foundation is usually as follows: the upper load is dispersed to the pile bodies and the soil between piles through the pile cap or cushion layer, and the pile bodies then transfer the load to the deep soil through the side friction resistance and end bearing capacity.
[0003] Prefabricated pile caps supporting pipe piles mostly adopt structures such as trapezoid, rectangle, T-shape, etc. The design focus is mainly on optimizing the connection strength between the pile cap and the pipe pile to ensure their integrity. However, the interaction between the existing pile cap and the filled soil is relatively single, and the utilization of the soil arch effect is not sufficient, resulting in a low load transfer efficiency to the pile bodies, and the cooperative bearing performance of the pile bodies and the soil between piles cannot be effectively exerted, ultimately limiting the improvement of the overall bearing capacity of the composite foundation. Summary of the Utility Model
[0004] The purpose of the utility model is to provide a pile cap, a pile column and a foundation to solve the technical problem that the interaction between the pile cap and the filled soil is relatively single, the utilization of the soil arch effect is not sufficient, resulting in the limitation of the overall bearing capacity of the foundation.
[0005] To achieve the above purpose, the utility model provides a pile cap, which includes a cap body, a first protruding part and a second protruding part. The first protruding part is arranged on the top surface of the cap body, the second protruding part is arranged around the outer side surface of the cap body, the top surface of the first protruding part is higher than the top surface of the second protruding part, and the distance between the outer side surface of the first protruding part and the axis of the cap body is less than the distance between the outer side surface of the second protruding part and the axis of the cap body.
[0006] Optionally, it further includes a plurality of the second protruding parts arranged in sequence from top to bottom. The top surface of the second protruding part located above is higher than the top surface of the second protruding part located below, and the distance between the outer side surface of the second protruding part located above and the axis of the cap body is less than the distance between the top surface of the second protruding part located below and the axis of the cap body.
[0007] Optionally, the outer contour of the cross-section perpendicular to the up-down direction of the first protruding part and the outer contour of the cross-section perpendicular to the up-down direction of the second protruding part are both rectangular.
[0008] Optionally, a connection hole is arranged on the bottom surface of the cap body, the connection hole is used for connecting the pile body, the diameter of the connection hole is set as D, and the diameter of the pile body is set as d.
[0009] Optional, d+10mm < D < d+20mm;
[0010] The distance from the bottom surface of the cap to the top surface of the first protrusion along the vertical direction is H, where 2d < H < 3d;
[0011] The area of the top surface of the first protrusion and the area of the top surface of the second protrusion are S, 4d 2 <S<16d 2 ;
[0012] The total number of the first protrusion and the second protrusion is set as i, and the height of the first protrusion and the height of the second protrusion are both h, (1 / i)×(2d)<h<(1 / i)×(3d);
[0013] The horizontal distance between the outer side of the second protrusion and the outer side of the first protrusion is greater than L. When there are multiple second protrusions, the horizontal distance between any two outer sides of the second protrusions is greater than L, where L > (1 / 2) × d.
[0014] Optionally, the outer surface of the first protrusion and the top surface and outer surface of the second protrusion are uneven surfaces.
[0015] This utility model also relates to a pile, including a pile body and the aforementioned pile cap, wherein the pile body is vertically disposed on the bottom surface of the pile cap and is fixedly connected to the pile cap.
[0016] Optionally, the bottom surface of the cap body is provided with a connecting hole, the pile body is inserted into the connecting hole and fixedly connected to the connecting hole, the diameter of the connecting hole is set as D, and the diameter of the pile body is d, where d+10<D<d+20.
[0017] This utility model also relates to a foundation having the aforementioned piles.
[0018] Optionally, it includes a first geogrid, a second geogrid, fill soil and deep soil, wherein the fill soil is placed above the deep soil, the pile body is inserted into the deep soil, and the pile cap, the first geogrid and the second geogrid are buried in the fill soil. The first geogrid is horizontally arranged on the side corresponding to the first protrusion, and the second geogrid is horizontally arranged on the side corresponding to the second protrusion.
[0019] Compared with the prior art, the pile cap, column pile, and foundation implemented in this utility model have the following advantages:
[0020] In this utility model of pile cap, the top surface of the cap body is provided with an upwardly protruding first protrusion, and the outer side of the cap body is provided with a horizontally protruding second protrusion. The height of the first protrusion is higher than that of the second protrusion, and the first protrusion is closer to the axis of the cap body than the second protrusion, so that the pile cap forms a stepped structure. The multiple steps of this stepped structure can form multiple independent soil arch support points in the fill at different depths. The upper surface of each step serves as the arch top support point, and the side of each step serves as the arch foot constraint. Local soil arches can be formed between the same layer of steps of adjacent pile caps. After the multiple soil arches are superimposed, the fill load at different depths can be transferred to the pile body in layers, avoiding the load from being concentrated at a single depth, improving the overall load transfer efficiency, and thus improving the bearing capacity of the foundation. Attached Figure Description
[0021] Figure 1 This is the front view of the pile cap of this utility model.
[0022] Figure 2 This is a top view of the pile cap of this utility model.
[0023] Figure 3 for Figure 2 Sectional view of AA.
[0024] Figure 4 The front view shows the uneven surface of the step of the pile cap of this utility model.
[0025] Figure 5 This is a cross-sectional view of the foundation of this utility model.
[0026] Figure descriptions: 1. Column pile; 11. Pile cap; 111. Cap body; 112. First protrusion; 113. Second protrusion; 114. Connecting hole; 12. Pile body; 2. Deep soil; 3. Backfill; 4. First geogrid; 5. Second geogrid. Detailed Implementation
[0027] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.
[0028] In the description of this utility model, it should be understood that the terms "top", "bottom", "inner", "outer", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the 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.
[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0030] like Figures 1 to 5 As shown, a pile cap 11 of this utility model includes a cap body 111, a first protrusion 112 and a second protrusion 113. The first protrusion 112 is disposed on the top surface of the cap body 111, and the second protrusion 113 is arranged around the outer side of the cap body 111. The top surface of the first protrusion 112 is higher than the top surface of the second protrusion 113. The distance between the outer side of the first protrusion 112 and the axis of the cap body 111 is less than the distance between the outer side of the second protrusion 113 and the axis of the cap body 111.
[0031] In the above technical solution, the top surface of the cap 111 is provided with an upwardly protruding first protrusion 112, and its outer side is provided with a horizontally protruding second protrusion 113. The height of the first protrusion 112 is higher than that of the second protrusion 113. The first protrusion 112 is closer to the axis of the cap 111 than the second protrusion 113, so that the pile cap 11 forms a stepped structure. The multiple steps of this stepped structure can form multiple independent soil arch support points in the fill 3 at different depths. The upper surface of each step serves as the arch top support point, and the side of each step serves as the arch foot constraint. Local soil arches can be formed between the same layer of steps of adjacent pile caps 11. After the multiple soil arches are superimposed, the load of the fill 3 at different depths can be transferred to the pile body 12 in layers, avoiding the load from being concentrated at a single depth, improving the overall load transfer efficiency, and thus improving the bearing capacity of the foundation.
[0032] Furthermore, it also includes a plurality of second protrusions 113 arranged sequentially from top to bottom. The top surface of the upper second protrusion 113 is higher than the top surface of the lower second protrusion 113. The distance between the outer side surface of the upper second protrusion 113 and the axis of the cap body 111 is less than the distance between the top surface of the lower second protrusion 113 and the axis of the cap body 111.
[0033] In particular, by increasing the number of second protrusions 113, the number of stepped structures is further increased, so that the pile cap 11 forms more steps of greater depth in the fill 3, thereby increasing the number and coverage depth of the soil arch and further enhancing the stability of the foundation bearing capacity.
[0034] Furthermore, the outer contours of the cross-section of the first protrusion 112 perpendicular to the vertical direction and the cross-section of the second protrusion 113 perpendicular to the vertical direction are both rectangular.
[0035] Among them, the rectangular cross section can ensure that the arch axis of the soil arch is more stable, the stress distribution of the arch body is more balanced, reduce the risk of local stress concentration or instability of the soil arch caused by irregular cross section, improve the reliability of the soil arch effect, ensure load transfer efficiency, and indirectly enhance the bearing capacity of the foundation.
[0036] Furthermore, the bottom surface of the cap 111 is provided with a connecting hole 114, which is used to connect the pile 12. The diameter of the connecting hole 114 is set as D, and the diameter of the pile 12 is set as d. The pile 12 is inserted into the connecting hole 114 to be fixedly connected to the cap 111, where D > d.
[0037] Furthermore, d+10mm < D < d+20mm. This size limit ensures the tightness of the pile body 12 when inserted into the connecting hole 114, avoiding excessive gaps that could cause shaking, while also reserving sufficient tolerance space for installation to facilitate construction and fixing.
[0038] Furthermore, the distance from the bottom surface of the cap 111 to the top surface of the first protrusion 112 along the vertical direction is H, 2d < H < 3d; the area of the top surface of the first protrusion 112 and the area of the top surface of the second protrusion 113 are S, 4d² < S < 16d²; the total number of the first protrusion 112 and the second protrusion 113 is set as i, and the height of the first protrusion 112 and the height of the second protrusion 113 are both h, (1 / i) × (2d) < h < (1 / i) × (3d); the aforementioned size limitation can ensure that each step has sufficient size as a support point for the earth arch, avoiding insufficient strength of the earth arch support point due to too small a size or waste of materials due to too large a size.
[0039] Furthermore, the horizontal distance between the outer side of the second protrusion 113 and the outer side of the first protrusion 112 is greater than L. When there are multiple second protrusions 113, the horizontal distance between any two outer sides of the second protrusions 113 is greater than L, where L > (1 / 2) × d. This size limitation can ensure that the side spacing of adjacent steps is reasonable, leaving enough space for the formation of the earth arch and avoiding the earth arch from being unable to unfold due to the steps being too close.
[0040] Furthermore, the outer surface of the first protrusion 112 and the top surface and outer surface of the second protrusion 113 are uneven surfaces.
[0041] The uneven surface increases the friction and mechanical interlocking force between the pile cap 11 and the backfill 3, reducing the relative slippage between the backfill 3 and the steps of the pile cap 11. Regarding the soil arching effect, the constraint strength of the arch foot (the side of the step) directly affects the stability of the soil arch. The uneven surface strengthens the constraint of the arch foot, preventing the soil arch from becoming unstable due to slippage. Simultaneously, the uneven surface of the top of the step (the arch support point) enhances the holding force on the backfill 3, ensuring the stable transfer of the arch load to the pile cap 11, further improving the bearing reliability of the soil arch, strengthening the synergistic effect between the pile cap 11 and the backfill 3, and thus improving the bearing capacity of the foundation.
[0042] Reference Figure 5 This embodiment also relates to a pile 1, including a pile body 12 and the aforementioned pile cap 11. The pile body 12 is vertically disposed on the bottom surface of the pile cap 11 and is fixedly connected to the pile cap 11.
[0043] Furthermore, the bottom surface of the cap 111 is provided with a connecting hole 114, the pile 12 is inserted into the connecting hole 114 and fixedly connected to the connecting hole 114, the diameter of the connecting hole 114 is set as D, and the diameter of the pile 12 is d, where d+10<D<d+20.
[0044] This size limitation ensures both the tightness of the pile body 12 when inserted into the connecting hole 114, preventing excessive gaps from causing shaking, and also provides sufficient tolerance space for installation, facilitating construction and fixing.
[0045] Reference Figure 5 This embodiment also relates to a foundation having the aforementioned pile 1.
[0046] Furthermore, it includes a first geogrid 4, a second geogrid 5, fill 3 and deep soil 2, the fill 3 is located above the deep soil 2, the pile body 12 is inserted into the deep soil 2, the pile cap 11, the first geogrid 4 and the second geogrid 5 are buried in the fill 3, the first geogrid 4 is horizontally arranged corresponding to the side of the first protrusion 112, and the second geogrid 5 is horizontally arranged corresponding to the side of the second protrusion 113.
[0047] The geogrid works in conjunction with the stepped sides of the stepped pile cap 11. The geogrid enhances the integrity of the fill 3, reduces lateral deformation of the fill 3, and serves as an auxiliary constraint structure for the soil arch: the first geogrid 4 corresponds to the side of the first protrusion 112, strengthening the arch foot constraint of the upper soil arch; the second geogrid 5 corresponds to the side of the second protrusion 113, strengthening the arch foot constraint of the lower soil arch. The synergistic effect of the geogrid and the soil arch not only improves the stability of the soil arch and prevents shear failure of the arch foot soil, but also disperses the load of the fill 3 through the tensile force of the geogrid. This superimposed effect of multiple soil arches and the reinforcement of the geogrid further strengthens the integrity between the pile and the soil, significantly improving the foundation's resistance to deformation and bearing capacity.
[0048] In addition, when there are multiple second protrusions 113, the second protrusions 113 may correspond to the second geogrid 5 or may not correspond to the second geogrid 5, but at least one second protrusion 113 corresponds to the second geogrid 5.
[0049] Furthermore, fixed setting and fixed connection refer to the fixed relative positional relationship of two components, including but not limited to fixing by connectors, fixing by welding, fixing by adhesive, fixing by integral molding, and fixing by snap-fit connection.
[0050] Furthermore, detachable connection and detachable setting refer to the ability of two components to be repeatedly assembled and disassembled without damage or severe deformation, including but not limited to fixing by connectors or fixing by snap-fit connections.
[0051] Furthermore, sliding connection and sliding setting refer to the connection between two connected components, where one component can slide along a fixed trajectory on the other component, including but not limited to connection by sliding a slider into a groove, or connection by inserting a slider into a hole whose size and profile match the slider.
[0052] Furthermore, adjustable connection and adjustable setting refer to the fact that the two connected components can be adjusted in their relative positions before being fixed, and the aforementioned adjustment and fixing process can be repeated, including but not limited to connection through elongated holes and connectors, and connection through sliding connection plus detachable connection.
[0053] Furthermore, rotatable connection and rotatable setting refer to the ability of two connected components to rotate, including but not limited to connections via bearings or clearance fits.
[0054] Furthermore, the connectors include, but are not limited to, fasteners, straps, ropes, pneumatic connectors, hydraulic connectors, flanges, Velcro, and buttons.
[0055] In summary, this utility model embodiment provides a pile cap 11, a pile 1, and a foundation, the technical effects of which are as follows:
[0056] In this utility model, the top surface of the cap 111 is provided with an upwardly protruding first protrusion 112, and the outer side of the cap is provided with a horizontally protruding second protrusion 113. The height of the first protrusion 112 is higher than that of the second protrusion 113. The first protrusion 112 is closer to the axis of the cap 111 than the second protrusion 113, so that the pile cap 11 forms a stepped structure. The multiple steps of this stepped structure can form multiple independent soil arch support points in the fill 3 at different depths. The upper surface of each step serves as the arch top support point, and the side of each step serves as the arch foot constraint. Local soil arches can be formed between the same layer of steps of adjacent pile caps 11. After the multiple soil arches are superimposed, the load of the fill 3 at different depths can be transferred to the pile body 12 in layers, avoiding the load from being concentrated at a single depth, improving the overall load transfer efficiency, and thus improving the bearing capacity of the foundation. The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.
Claims
1. A pile cap (11) characterized in that, The cap includes a cap body (111), a first protrusion (112), and a second protrusion (113). The first protrusion (112) is disposed on the top surface of the cap body (111), and the second protrusion (113) is disposed around the outer side of the cap body (111). The top surface of the first protrusion (112) is higher than the top surface of the second protrusion (113). The distance between the outer side of the first protrusion (112) and the axis of the cap body (111) is less than the distance between the outer side of the second protrusion (113) and the axis of the cap body (111).
2. A pile cap (11) according to claim 1, characterized in that It also includes a plurality of second protrusions (113) arranged sequentially from top to bottom. The top surface of the upper second protrusion (113) is higher than the top surface of the lower second protrusion (113). The distance between the outer side surface of the upper second protrusion (113) and the axis of the cap body (111) is less than the distance between the top surface of the lower second protrusion (113) and the axis of the cap body (111).
3. A pile cap (11) according to claim 1, characterized in that The outer contours of the cross section perpendicular to the vertical direction of the first protrusion (112) and the cross section perpendicular to the vertical direction of the second protrusion (113) are both rectangular.
4. A pile cap (11) according to claim 1, characterized in that The bottom surface of the cap (111) is provided with a connecting hole (114), which is used to connect the pile body (12). The diameter of the connecting hole (114) is set to D, and the diameter of the pile body (12) is set to d.
5. A pile cap (11) according to claim 4, characterized in that d+10mm<D<d+20mm; The distance from the bottom surface of the cap body (111) to the top surface of the first protrusion (112) in the vertical direction is H, where 2d < H < 3d; The area of the top surface of the first protrusion (112) and the area of the top surface of the second protrusion (113) are S, 4d 2 <S<16d 2 ; The total number of the first protrusion (112) and the second protrusion (113) is set as i, and the height of the first protrusion (112) and the height of the second protrusion (113) are both h, (1 / i)×(2d)<h<(1 / i)×(3d); The horizontal distance between the outer side of the second protrusion (113) and the outer side of the first protrusion (112) is greater than L. When there are multiple second protrusions (113), the horizontal distance between any two outer sides of the second protrusions (113) is greater than L, where L > (1 / 2) × d.
6. A pile cap (11) according to claim 1, characterized in that The outer surface of the first protrusion (112) and the top surface and outer surface of the second protrusion (113) are uneven surfaces.
7. A pile (1) characterized in that It includes a pile body (12) and a pile cap (11) according to any one of claims 1 to 6, wherein the pile body (12) is vertically disposed on the bottom surface of the pile cap (11) and fixedly connected to the pile cap (11).
8. A pile (1) according to claim 7, characterised in that The bottom surface of the cap (111) is provided with a connecting hole (114). The pile (12) is inserted into the connecting hole (114) and fixedly connected to the connecting hole (114). The diameter of the connecting hole (114) is set as D, and the diameter of the pile (12) is d, where d+10<D<d+20.
9. A foundation, characterized in that The column pile (1) as described in claim 7 or 8 is provided.
10. The foundation according to claim 9, characterized in that It includes a first geogrid (4), a second geogrid (5), fill (3) and deep soil (2). The fill (3) is located above the deep soil (2). The pile body (12) is inserted into the deep soil (2). The pile cap (11), the first geogrid (4) and the second geogrid (5) are buried in the fill (3). The first geogrid (4) is horizontally arranged on the side corresponding to the first protrusion (112), and the second geogrid (5) is horizontally arranged on the side corresponding to the second protrusion (113).