Screw pile foundation and photovoltaic power generation system

Abstract

The application relates to a screw pile foundation and a photovoltaic power generation system, which comprises a screw steel pile, a first pile body and a second pile body arranged in the axial direction, the first pile body being located in the foundation soil; a concrete solidification layer located in the foundation soil and exposed to the foundation soil, the concrete solidification layer wrapping at least part of the second pile body; and a connecting member detachably connected to the second pile body, the connecting member comprising a plurality of shear plates extending in the radial direction of the second pile body, the plurality of shear plates being arranged in the axial direction of the second pile body and embedded in the concrete solidification layer. The application mechanically connects the screw steel pile and the concrete through the embedded shear plates, effectively solving the problem of insufficient bearing capacity of the screw pile in the soft soil in the related art; and the plurality of shear plates arranged in the circumferential direction of the second pile body can effectively resist the horizontal load from any direction, which is beneficial to transmitting the load from the screw steel pile to the concrete and realizing omnidirectional shearing resistance.

Description

Technical Field

[0001] This application relates to the field of helical pile construction technology, and in particular to helical pile foundations and photovoltaic power generation systems. Background Technology

[0002] With the large-scale construction of new energy projects such as photovoltaic power generation worldwide, the demand for their support foundations is enormous. Photovoltaic support foundations primarily bear the horizontal and uplift forces from wind loads, especially in typhoon-prone areas where the horizontal bearing capacity requirements are extremely high. In overseas projects, constrained by local construction technology, material supply, and cost control, helical steel pile foundations have become a widely adopted foundation type due to their advantages such as rapid construction, no maintenance required, and minimal site disturbance.

[0003] However, when encountering soft soil layers, the lateral restraint and end resistance provided by the surrounding soil of helical steel piles are significantly reduced, making it difficult for their horizontal and vertical bearing capacities to meet design requirements. Simply increasing the pile diameter, pile length, or number of blades to improve bearing capacity would greatly increase material costs and construction difficulty, resulting in poor economic efficiency. Utility Model Content

[0004] Based on this, it is necessary to provide a helical pile foundation and photovoltaic power generation system to address the problem that when helical steel piles encounter soft soil layers, the lateral restraint and end resistance provided by the soil around the pile are significantly reduced, resulting in the horizontal and vertical bearing capacities often failing to meet design requirements.

[0005] In a first aspect, embodiments of this application provide a helical pile foundation, including:

[0006] A spiral steel pile includes a first pile body and a second pile body arranged along the axial direction, wherein the first pile body is located in the foundation soil and is in contact with the foundation soil;

[0007] A concrete curing layer is located within the foundation soil and exposed outside the foundation soil, and the concrete curing layer encloses at least a portion of the second pile body;

[0008] A connecting member, detachably connected to the second pile body, the connecting member comprising a plurality of shear plates extending radially along the second pile body, the plurality of shear plates being arranged axially spaced around the second pile body, the plurality of shear plates being embedded within the concrete curing layer, the shear plates being configured to transfer the load of the helical steel pile to the concrete curing layer.

[0009] In one embodiment, the connecting member further includes a base plate connecting two adjacent shear plates, the base plate and the shear plates forming a first member; the connecting member includes at least two first members;

[0010] The foundation plate includes an arc-shaped segment adapted to the side wall of the second pile body, and the shear plates located at both ends of the foundation plate have an included angle with the foundation plate, the included angle being 90°-120°.

[0011] In one embodiment, the connecting member includes two first members, which are symmetrically arranged about the axis of the second pile.

[0012] In one embodiment, at least two of the connecting members are spaced apart along the axial direction of the second pile body;

[0013] The connecting member further includes a fastener for securing at least two of the first members in one of the connecting members.

[0014] In one embodiment, the shear plate is sheet-like, and the large surface of the shear plate is parallel to the axis of the second pile body.

[0015] In one embodiment, the outer wall of the second pile body is provided with an annular groove, and the arc-shaped segment of the foundation plate is at least partially embedded in the annular groove;

[0016] The arc-shaped segment is semi-circular.

[0017] In one embodiment, the shear plate has a predetermined distance from one end away from the base plate to the outer edge of the concrete curing layer.

[0018] In one embodiment, the shear plate has a rough surface.

[0019] And / or, the surface of the shear plate is configured with a plurality of reinforcing blocks that extend along the surface away from the shear plate;

[0020] And / or, the surface of the shear plate has a plurality of perforations;

[0021] And / or, the shear plate has a bent section at one end away from the base plate;

[0022] And / or, along the axial direction of the second pile body, the orthographic projection of the shear plate is wavy.

[0023] In one embodiment, the helical steel pile further includes helical blades arranged around the outer periphery of the first pile body.

[0024] Secondly, embodiments of this application provide a photovoltaic power generation system, including a photovoltaic support frame and at least one helical pile foundation as described in the first aspect, wherein the photovoltaic support frame is installed on top of the helical steel pile.

[0025] The aforementioned helical pile foundation and photovoltaic power generation system pre-drives helical steel piles into the foundation soil, ensuring the first pile body is in contact with the soil while the second pile body is located in a pit near the soil surface. After installing connecting components around the second pile body, concrete is filled into the pit to form a solidified concrete layer enclosing part of the second pile body and the connecting components. This solidified concrete layer not only increases the contact area between the foundation and the foundation soil, but also, through mechanical interlocking, rigidly connects the helical steel pile to the concrete using embedded shear plates, effectively solving the problem of insufficient bearing capacity of simple helical piles in soft soil in related technologies. Furthermore, the multiple shear plates arranged circumferentially along the second pile body can effectively handle horizontal loads from any direction, facilitating the transfer of load from the helical steel pile to the concrete and achieving omnidirectional shear resistance. Attached Figure Description

[0026] Figure 1 This is a schematic cross-sectional view of a helical pile foundation provided according to some embodiments of this application.

[0027] Figure 2 for Figure 1 A schematic diagram of the cross-section at point AA.

[0028] Figure 3 This is a schematic diagram of the overall structure of the connecting member provided according to some embodiments of this application.

[0029] Figure 4 This is a front view structural schematic diagram of a connecting member provided according to some embodiments of this application.

[0030] Figure 5 This is a top view of a connecting member provided according to some embodiments of this application.

[0031] Figure 6 This is a side view of a connecting member provided according to some embodiments of this application.

[0032] Icon labels:

[0033] 100. Helical steel pile; 110. First pile body; 111. Helical blade; 120. Second pile body;

[0034] 200. Concrete curing layer;

[0035] 300. Connecting component; 310. Shear plate; 320. Base plate; 321. Curved segment; 322. Straight segment; 323. Mounting hole; 330. Fastener. Detailed Implementation

[0036] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0037] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0038] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0040] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0041] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0042] As mentioned in the background section, to overcome the shortcomings of helical piles in soft soil, traditional cast-in-place pile foundation schemes are often adopted. This scheme typically includes steps such as drilling, lowering the reinforcing cage, and pouring concrete. Although it can provide high bearing capacity, it has the following significant drawbacks: it requires drilling, and in soft soil foundations, measures such as mud wall protection or steel casing are often required to prevent the hole from collapsing. The process is complicated and the construction period is long. For a large number of photovoltaic foundations, the total cost and construction period will increase significantly. Furthermore, when the helical steel pile is directly placed into the hole as part of the reinforcing cage and then concrete is poured, the connection between the steel pile and the concrete mainly depends on the bond strength at the interface. Under long-term alternating loads such as wind loads, this bond interface is prone to degradation or even failure, resulting in relative slippage between the steel pile and the concrete, which seriously affects the integrity and long-term safety of the structure.

[0043] To address the aforementioned problems, this application provides a helical pile foundation and photovoltaic power generation system. Helical steel piles are pre-driven into the foundation soil, ensuring the first pile body is in contact with the soil. A second pile body is located in a pit near the soil surface. Connecting components are installed around the second pile body, and concrete is filled into the pit to form a solidified concrete layer enclosing part of the second pile body and the connecting components. This solidified concrete layer not only increases the contact area between the foundation and the soil but also, through mechanical interlocking, rigidly connects the helical steel pile to the concrete using embedded shear plates, effectively solving the problem of insufficient bearing capacity of simple helical piles in soft soil in related technologies. Furthermore, the multiple shear plates arranged circumferentially along the second pile body effectively handle horizontal loads from any direction, facilitating the transfer of load from the helical steel pile to the concrete and achieving omnidirectional shear resistance.

[0044] See Figure 1 and Figure 2 , Figure 1 This is a schematic cross-sectional view of a helical pile foundation provided according to some embodiments of this application. Figure 2 for Figure 1 A schematic cross-sectional view at point AA. An embodiment of this application provides a helical pile foundation that may include a helical steel pile 100, a concrete curing layer 200, and a connecting member 300.

[0045] The spiral steel pile 100 includes a first pile body 110 and a second pile body 120 arranged axially. The first pile body 110 is located in and in contact with the foundation soil. A concrete curing layer 200 is located in and exposed to the foundation soil, and the concrete curing layer 200 encloses at least a portion of the second pile body 120. A connecting member 300 is detachably connected to the second pile body 120. The connecting member 300 includes a plurality of shear plates 310 extending radially along the second pile body 120. The plurality of shear plates 310 are arranged at intervals around the axial direction of the second pile body 120 and are embedded within the concrete curing layer 200. The shear plates 310 are configured to transfer the load of the spiral steel pile 100 to the concrete curing layer 200.

[0046] It is understood that the helical pile foundation described in this embodiment is an integral structure that has already been constructed. During the construction process, an area in the foundation soil that needs to be solidified by concrete can be excavated in advance, for example, a shallow cylindrical foundation pit can be excavated, and then the helical steel pile 100 can be driven through the excavated area and driven into the design depth; or, the helical steel pile 100 can be driven into the design depth first, and then an area (foundation pit) that needs to be solidified can be excavated around the helical steel pile 100.

[0047] For ease of description, in this embodiment, the portion of the spiral steel pile 100 located in the foundation soil is referred to as the first pile body 110, while the portion located in the excavation area and the portion located on the ground surface are referred to as the second pile body 120. In reality, the first pile body 110 and the second pile body 120 can be formed integrally, but there is no specific limitation.

[0048] The outer surface of the first pile shaft 110, located in the foundation soil, will be in direct contact with the foundation soil. In some embodiments, the helical steel pile 100 also includes helical blades 111, which are arranged around the outer periphery of the first pile shaft 110. Specifically, the arrangement of the helical blades 111 on the outer periphery of the first pile shaft 110 can be achieved by screwing the helical steel pile 100 into the deep soil. The first pile shaft 110 mainly utilizes the interlocking of the helical blades 111 with the soil to provide vertical compressive and tensile bearing capacity.

[0049] The second pile body 120 is located near the ground surface. Before the concrete curing layer 200 is formed, the second pile body 120 is located in the excavated foundation pit. During this process, the connecting component 300 needs to be set on the second pile body 120. For example, the connecting component 300 can be fixed to the outer periphery of the second pile body 120 by means of bolt connection, clamp locking, or other detachable methods.

[0050] Subsequently, concrete is filled into the excavated foundation pit (forming a concrete curing layer 200). The concrete will encase at least part of the second pile body 120 and the connecting member 300. Since the connecting member 300 includes a plurality of shear plates 310 extending into the concrete, and the plurality of shear plates 310 are circumferentially arranged around the outer periphery of the second pile body 120, they can combine with the concrete to form a shear structure, that is, they can form a strong mechanical interlock with the concrete.

[0051] Furthermore, when a horizontal load is applied to the top of the helical steel pile 100, the second pile body 120 tends to bend and undergo horizontal displacement. During this process, the shear plate 310 fixed to the second pile body 120 will transfer the force from the top to the surrounding concrete curing layer 200. In this embodiment, by setting multiple shear plates 310 on the outer periphery of the second pile body 120, and more preferably by setting the multiple shear plates 310 radially offset relative to the second pile body 120, it is ensured that the load from the top is effectively resisted by the shear plate 310 regardless of the direction from which it comes, thus achieving omnidirectional shear resistance.

[0052] Of course, when the second pile body 120 is under tension, the upper surface of the shear plate 310 will also press against the concrete above, thereby dispersing the upward pull force into the concrete curing layer 200, which is beneficial to improving the vertical pull-out bearing capacity.

[0053] In summary, the helical pile foundation provided in this application involves pre-driving helical steel piles 100 into the foundation soil, ensuring that the first pile body 110 is in contact with the foundation soil, while the second pile body 120 is located in the foundation pit near the surface of the foundation soil. After setting connecting members 300 around the second pile body 120, concrete is filled into the foundation pit to form a concrete curing layer 200 that partially encloses the second pile body 120 and the connecting members 300. The concrete curing layer 200 not only increases the contact area between the foundation and the foundation soil, but also, through mechanical interlocking, the embedded shear plates 310 rigidly connect the helical steel pile 100 to the concrete, effectively solving the problem of insufficient bearing capacity of simple helical piles in soft soil in related technologies. Furthermore, the multiple shear plates arranged circumferentially along the second pile body 120 can effectively handle horizontal loads from any direction, facilitating the transfer of load from the helical steel pile 100 to the concrete and achieving omnidirectional shear resistance.

[0054] Below, we will combine the appendix Figure 1 - Appendix Figure 6 The specific structure of the helical pile foundation provided in the embodiments of this application will be described in detail.

[0055] like Figure 3 Hezhi Figure 6 As shown, Figure 3 This is a schematic diagram of the overall structure of the connecting member provided according to some embodiments of this application. Figure 4 This is a front view structural schematic diagram of a connecting member provided according to some embodiments of this application. Figure 5 This is a top view of a connecting member provided according to some embodiments of this application. Figure 6 This is a side view of a connecting member provided according to some embodiments of this application. In some embodiments, the connecting member 300 further includes a base plate 320 connecting two adjacent shear plates 310, the base plate 320 and the shear plates 310 forming a first member; the connecting member 300 includes at least two first members; the base plate 320 includes an arc-shaped segment 321 adapted to the side wall of the second pile body 120, and the shear plates 310 located at both ends of the base plate 320 have an included angle with the base plate 320, the included angle being 90°-120°.

[0056] It is understood that the entire connecting member 300 can be formed by splicing together at least two of the above-mentioned first members. The base plate 320 includes an arc segment 321 and a straight segment 322 connected to both ends of the arc segment 321. The two ends of the straight segment 322 are used to connect the shear plate 310. The straight segment 322 is used to provide mounting holes 323 so that bolts can pass through to connect adjacent base plates 320.

[0057] The angle between the shear plate 310 and the base plate 320 ensures that the shear plate 310 does not extend radially, which is beneficial for achieving omnidirectional shear resistance. In this example, the first component can be manufactured as a standard part, which helps reduce manufacturing costs.

[0058] like Figure 2 As shown, in some embodiments, the connecting member 300 includes two first members that are symmetrically arranged about the axis of the second pile body 120.

[0059] Specifically, the arrangement of the two first components ensures that the center of mass of the connecting component 300 coincides with the axis of the second pile body 120, avoiding eccentricity caused by unevenness, thereby ensuring the symmetry and balance of force transmission under load and improving the bearing efficiency and stability of the foundation.

[0060] like Figure 2 As shown, in some embodiments, at least two connecting members 300 are provided at intervals along the axial direction of the second pile body 120; the connecting member 300 further includes a fastener 330 for fixing at least two first members in a connecting member 300.

[0061] Specifically, the multiple connecting members 300 arranged axially are equivalent to setting multiple reinforcing ribs at different heights of the second pile body 120, which expands the load transfer path from a single plane to a three-dimensional space, greatly improving the bending resistance of the second pile body 120.

[0062] like Figure 3 As shown, in some embodiments, the shear plate 310 is sheet-like, with its large surface parallel to the axis of the second pile body 120. Specifically, the sheet-like structure maximizes the contact area with concrete while ensuring sufficient shear stiffness. The large surface of the shear plate 310 being parallel to the axis provides an effective bearing surface when subjected to horizontal loads from any direction.

[0063] In some embodiments, the outer wall of the second pile body 120 is constructed with an annular groove, and the arc-shaped segment 321 of the foundation plate 320 is at least partially embedded in the annular groove; the arc-shaped segment 321 is semi-circular.

[0064] Specifically, the annular groove and the embedded arc segment 321 form a mechanical interlock to prevent the connecting member 300 from axially sliding on the second pile body 120, so as to ensure that the connecting member 300 is always in the designed position during construction and use.

[0065] like Figure 2As shown, in some embodiments, the shear plate 310 has a predetermined distance from the end furthest from the foundation slab 320 to the outer edge of the concrete curing layer 200. Specifically, this predetermined distance ensures that the outer end of the shear plate 310 is encased in sufficiently thick concrete, preventing the load from being directly transferred from the end of the shear plate 310 to the concrete surface under high stress, thus avoiding spalling or splitting of the concrete cover and ensuring the structural integrity of the concrete curing layer 200. For example, along the radial direction of the second pile body 120, the ratio of the size of the shear plate 310 to the size of the concrete is 2:3, but this is not specifically limited.

[0066] In some embodiments, the surface of the shear plate 310 is roughened. Exemplarily, this is achieved through sandblasting, rolling, or the like.

[0067] In one example, the surface of the shear plate 310 is constructed with a plurality of reinforcing blocks that extend along the surface away from the shear plate 310.

[0068] In one example, the surface of the shear plate 310 has multiple perforations.

[0069] In one example, the shear plate 310 has a bent section at the end facing away from the base plate 320. Exemplarily, the bent section is hook-shaped or L-shaped.

[0070] In one example, the orthographic projection of the shear plate 310 along the axial direction of the second pile body 120 is wavy.

[0071] The above-mentioned optimization of the surface or end structure of the shear plate 310 can further increase the contact area and mechanical interlocking effect between the shear plate 310 and the concrete.

[0072] Based on the same concept, this application also provides a photovoltaic power generation system, which may include a photovoltaic support and at least one helical pile foundation as described in the above embodiments, with the photovoltaic support installed on top of the helical steel pile 100.

[0073] It is understood that the photovoltaic support can be securely installed on top of the helical steel pile 100 by means of bolts or welding, but there are no restrictions. When wind loads, snow loads, etc., act on the photovoltaic support and panels, the resulting horizontal force, uplift force, and bending moment are transmitted to the helical pile foundation through the support. The foundation utilizes its resistance to horizontal force and uplift to safely distribute these loads into the ground. The specific principle can be understood by referring to the above embodiment to ensure the stable operation of the entire photovoltaic power station.

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A helical pile foundation, characterized in that, include: The spiral steel pile (100) includes a first pile body (110) and a second pile body (120) arranged along the axial direction, wherein the first pile body (110) is located in the foundation soil and is in contact with the foundation soil; A concrete curing layer (200) is located within the foundation soil and exposed to the foundation soil, and the concrete curing layer (200) covers at least a portion of the second pile body (120). A connecting member (300) is detachably connected to the second pile body (120). The connecting member (300) includes a plurality of shear plates (310) extending radially along the second pile body (120). The plurality of shear plates (310) are arranged axially spaced around the second pile body (120). The plurality of shear plates (310) are embedded within the concrete curing layer (200). The shear plates (310) are configured to transfer the load of the helical steel pile (100) to the concrete curing layer (200).

2. The helical pile foundation according to claim 1, characterized in that, The connecting member (300) further includes a base plate (320) connecting two adjacent shear plates (310), the base plate (320) and the shear plate (310) forming a first member; the connecting member (300) includes at least two of the first members; The foundation plate (320) includes an arc-shaped segment (321) adapted to the side wall of the second pile body (120). The shear plates (310) located at both ends of the foundation plate (320) have an included angle with the foundation plate (320), which is 90°-120°.

3. The helical pile foundation according to claim 2, characterized in that, The connecting member (300) includes two first members, which are symmetrically arranged about the axis of the second pile body (120).

4. The helical pile foundation according to claim 2, characterized in that, At least two of the connecting members (300) are provided at intervals along the axial direction of the second pile body (120). The connecting member (300) further includes a fastener (330) for securing at least two of the first members in one of the connecting members (300).

5. The helical pile foundation according to any one of claims 1-4, characterized in that, The shear plate (310) is sheet-shaped, and the large surface of the shear plate (310) is parallel to the axis of the second pile body (120).

6. The helical pile foundation according to any one of claims 2-4, characterized in that, The outer wall of the second pile body (120) is constructed with an annular groove, and the arc-shaped segment (321) of the foundation plate (320) is at least partially embedded in the annular groove; The arc segment (321) is semi-circular.

7. The helical pile foundation according to any one of claims 2-4, characterized in that, The shear plate (310) has a predetermined distance from one end away from the base plate (320) to the outer side of the concrete curing layer (200).

8. The helical pile foundation according to any one of claims 2-4, characterized in that, The surface of the shear plate (310) is rough. And / or, the surface of the shear plate (310) is configured with a plurality of reinforcing blocks that extend along a surface away from the shear plate (310); And / or, the surface of the shear plate (310) is configured with a plurality of perforations; And / or, the shear plate (310) has a bent section at one end away from the base plate (320); And / or, along the axial direction of the second pile body (120), the orthographic projection of the shear plate (310) is wavy.

9. The helical pile foundation according to any one of claims 1-4, characterized in that, The spiral steel pile (100) also includes a spiral blade (111), which is arranged around the outer periphery of the first pile body (110).

10. A photovoltaic power generation system, characterized in that, It includes a photovoltaic support structure and at least one helical pile foundation as described in any one of claims 1-9, wherein the photovoltaic support structure is mounted on top of the helical steel pile (100).

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