A micro-pile foundation and power transmission line

Abstract

This utility model discloses a steel pipe micro-pile foundation and a power transmission line, relating to the field of power transmission line technology. The steel pipe micro-pile foundation includes: a foundation trench and vertical and inclined piles arranged at an angle within the trench. The vertical piles connect to the inclined piles, and the upper ends of the vertical piles are connected to a truss. The upper ends of the truss are provided with tower foot plates for connecting the tower legs. This steel pipe micro-pile foundation solves the technical problem that existing micro-pile foundations have low horizontal lateral resistance, are only suitable for straight towers or small-angle towers with low loads, and cannot be used for straight towers or large-angle towers with high loads, thus greatly limiting their application scenarios. By combining vertical and inclined piles to form a sub-foundation spatial truss structure, the overall lateral resistance and bearing capacity of the micro-pile foundation are improved, making it suitable for straight towers with high loads or large-angle towers with high horizontal forces. This significantly expands the application scenarios of micro-pile foundations and enables large-scale application.

Description

Technical Field

[0001] This utility model relates to the field of power transmission line technology, and in particular to a micro-pillar foundation and a power transmission line. Background Technology

[0002] In mountainous power transmission construction, the relocation of construction equipment and materials is extremely difficult, and the long-standing drawbacks of high labor input and outdated construction methods pose a significant challenge to the mechanization of power grid construction. However, miniaturization and lightweighting of foundations can drive the lightweighting of equipment, representing a crucial breakthrough direction for the mechanization of power transmission line construction in mountainous areas and overcoming outdated construction methods. Steel pipe micropile foundations, due to their small cross-section, can achieve miniaturization, lightweighting, and portable equipment, enabling a degree of mechanization. Existing technology discloses an embedded prefabricated micropile foundation for power transmission lines, which uses trusses to replace large-volume pile caps, achieving lightweighting and prefabrication of the pile caps, facilitating transportation and relocation in mountainous areas, and realizing the mechanization of power transmission line construction in mountainous regions.

[0003] However, the aforementioned micropile foundations only have one vertical pile supporting the tower leg, resulting in a bearing capacity far lower than traditional steel pipe micropile foundations. Furthermore, their horizontal lateral resistance is relatively small, limiting their application to straight towers or small-angle towers with lower loads. This significantly restricts their application scenarios and hinders large-scale deployment. Therefore, this paper proposes a steel pipe micropile group foundation and transmission line solution to address these issues. Utility Model Content

[0004] The purpose of this utility model is to provide a micro pile foundation and transmission line, which solves the technical problem that the existing micro pile foundation has low horizontal lateral resistance and can only be applied to straight towers or small angle towers with small loads, but not to straight towers or large angle towers with large loads, thus greatly limiting its application scenarios.

[0005] To achieve the above objectives, this utility model provides a micro-pillar foundation for supporting the tower legs of a steel tower, comprising: a foundation trench and vertical and inclined piles arranged at an angle within the foundation trench, wherein the vertical piles are connected to the inclined piles, and the upper end of the vertical piles is connected to a truss, and the upper end of the truss is provided with a tower foot plate for connecting the tower legs.

[0006] Preferably, four vertical piles are provided in the foundation trench, and each vertical pile is connected to two or more inclined piles.

[0007] Preferably, a top plate is provided at the upper end of the vertical pile, the top plate is connected to the lower end of the truss, and the top plate is connected to the upper end of the inclined pile.

[0008] Preferably, a first ear plate is provided on the top surface of the top plate, and a first node plate is provided at the lower end of the truss. The first ear plate is connected to the first node plate by a first pin.

[0009] Preferably, a second node plate is provided on the bottom surface of the top plate, and a second ear plate is provided at the upper end of the inclined pile. The second node plate is connected to the second ear plate by a second pin.

[0010] Preferably, the bottom of the foundation trench is provided with vertical holes and inclined holes, with vertical piles embedded in the vertical holes and inclined piles embedded in the inclined holes.

[0011] Preferably, the gap between the vertical hole and the vertical pile, and the gap between the inclined hole and the inclined pile, are filled with a consolidation material, which is M30 mortar or fine stone concrete.

[0012] Preferably, a protective cap is provided at the top plate location.

[0013] Preferably, the trench is backfilled with soil material, and the soil material is flush with the ground surface.

[0014] A power transmission line comprising the micro-pile foundation described in any of the preceding claims.

[0015] Compared to the aforementioned background technology, the micro pile group foundation provided by this utility model has the following beneficial effects: by setting inclined piles with higher lateral force resistance around the vertical piles, and the inclined piles are set at an angle to the vertical piles and connected to the inclined piles, the vertical piles and inclined piles form a joint pile group that converges at the same node, thereby forming a sub-foundation spatial truss structure, which effectively improves the overall lateral force resistance level of the micro pile group foundation, and at the same time significantly improves the bearing capacity of the micro pile group foundation, so as to be suitable for straight towers with large loads or large angle iron towers with large horizontal forces, making the application range of the micro pile group foundation wider, thereby greatly expanding the application scenarios of the micro pile group foundation and realizing large-scale application. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 A cross-sectional schematic diagram of a micro-pile group foundation provided in an embodiment of this utility model;

[0018] Figure 2 A top view of a micro-pile foundation provided in an embodiment of this utility model;

[0019] Figure 3 for Figure 1 Enlarged view of point A in the middle;

[0020] Figure 4 for Figure 1 Schematic diagram of the cross section at point BB;

[0021] Figure 5 This is the first embodiment of the present utility model. Figure 3 Cross-sectional view at point CC;

[0022] Figure 6 for Figure 3 Schematic diagram of the cross section at point DD;

[0023] Figure 7 A top view of the micro-pile foundation provided in the second embodiment of this utility model;

[0024] Figure 8 This is the second embodiment of the present utility model. Figure 3 Cross-sectional view at point CC;

[0025] Figure 9 A top view of the micro-pile foundation provided in the third embodiment of this utility model;

[0026] Figure 10 This is the third embodiment of the present utility model. Figure 3 A cross-sectional view at point CC.

[0027] Specifically, 1-foundation trench; 101-vertical hole; 102-slanted hole; 2-vertical pile; 3-slanted pile; 301-second ear plate; 4-truss; 401-first node plate; 5-tower foot plate; 6-top plate; 601-first ear plate; 602-second node plate; 7-protective cap; 8-first pin; 9-second pin; 10-consolidation material. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] like Figure 1 and Figure 2 As shown, to achieve the above objectives, this utility model provides a micro-pile group foundation, comprising: a foundation trench 1 and vertical piles 2 and inclined piles 3 arranged at an angle within the foundation trench 1. In rocky areas with a cover layer of approximately 2 meters, the foundation trench 1 is excavated to remove the surface soft soil, and vertical piles 2 and inclined piles 3 are installed at the bottom of the foundation trench 1. At least one inclined pile 3 is installed around each vertical pile 2. By installing inclined piles 3 with higher lateral force resistance around the vertical piles, and by setting the inclined piles 3 at an angle to and connecting the inclined piles 3, the vertical piles and inclined piles 3 mutually constrain each other. By forming a unified structure, the bearing capacity of the micropiles is increased, allowing the vertical and inclined piles 3 to converge at the same node to form a combined pile group, thereby creating a sub-foundation spatial truss structure. This effectively improves the overall lateral force resistance of the micropiles foundation and significantly enhances its bearing capacity, making it suitable for straight towers with large loads or large-angle iron towers with large horizontal forces. This broadens the application range of micropiles foundations, greatly expanding their application scenarios and enabling large-scale application, especially in mountainous areas with thick soil layers or thick layers of weak surface soil. Furthermore, a truss 4 is connected to the upper end of the vertical piles 2. A tower foot plate 5 is installed at the upper end of the truss 4, and the upper end of the truss 4 is bolted to the tower foot plate 5. The top surface of the tower foot plate 5 is bolted to the four sub-legs of the tower leg.

[0031] It should be noted that both vertical pile 2 and inclined pile 3 are steel pipe micropiles, achieving lightweighting of the micro pile group foundation. Moreover, the original single-pillar foundation is decomposed into detachable prefabricated components such as vertical pile 2, inclined pile 3, and truss 4, which facilitate transportation and realize the prefabrication of the micro pile group foundation. This ensures that the construction of high-voltage and high-load transmission lines in mountainous areas can achieve mechanized and prefabricated construction, effectively reducing manpower input on the construction site, improving construction safety and quality, and increasing construction efficiency.

[0032] In some embodiments of this utility model, four vertical piles 2 are set in the foundation trench 1, and one vertical pile 2 is set for each of the four sub-legs of each tower leg. That is, the layout of four vertical piles 2 under one tower leg allows the load of each sub-leg of the tower leg to be directly and evenly transferred to the corresponding vertical pile 2, avoiding the problem of local stress concentration, improving the stress balance and structural stability of the entire tower leg, so as to meet the usage requirements of high voltage level and large load transmission lines in mountainous areas.

[0033] In practical applications, each vertical pile 2 is connected to two or more inclined piles 3. One, two, or three inclined piles 3 are added as needed based on the actual load. This allows for flexible adjustment of the micro-pile foundation for each tower leg. For example... Figure 1 and Figure 5As shown, each sub-leg is supported by one vertical stake 2 and one inclined stake 3. Figure 7 and Figure 8 As shown, each sub-leg is supported by one vertical stake 2 and two inclined stakes 3. Figure 9 and Figure 10 As shown, each sub-leg is equipped with one vertical pile 2 and three inclined piles 3, with multiple layout options to precisely match different load requirements. At the same time, the four vertical piles and the corresponding number of inclined piles 3 form a joint pile group connecting truss 4, and the upper ends of the four trusses 4 are connected to the tower foot plate 5, effectively improving the bearing capacity of the micro pile group foundation to meet the needs of high voltage level and heavy load transmission lines in mountainous areas.

[0034] In some embodiments of this utility model, a top plate 6 is provided at the upper end of the vertical pile 2. The top plate 6 is connected to the lower end of the truss 4 and the upper end of the inclined pile 3. The top plate 6 serves as a connecting member to support the lower end of the truss 4 and the upper end of the inclined pile 3, thus constructing a rigid connection node between the vertical pile 2, the inclined pile 3 and the truss 4. This allows the load on the truss 4 to be quickly and evenly transferred to the entire sub-foundation space truss structure through the top plate 6, avoiding the problem of disordered force transmission path, improving the structural strength and stability of the overall micro pile foundation, and enabling the micro pile foundation to better bear and disperse the vertical pressure and horizontal thrust of high-load, high-voltage transmission line corner towers, so as to adapt to the complex construction and stress conditions in mountainous areas.

[0035] like Figure 3 and Figure 6 As shown, in some embodiments of this utility model, a first ear plate 601 is provided on the top surface of the top plate 6, and a first node plate 401 is provided at the lower end of the truss 4. The first ear plate 601 is connected to the first node plate 401 by a first pin 8. The top surface of the top plate 6 is set at an angle to the length direction of the truss 4. The rigid connection between the top plate 6 and the truss 4 is achieved by the first pin 8. By utilizing the structural characteristics of the pin connection, the on-site installation process of the intersection node of the top plate 6 and the truss 4 is simplified, the construction difficulty is reduced, and the assembly efficiency of the overall micro pile group foundation is improved.

[0036] Similarly, such as Figure 3 and Figure 5 As shown, a second node plate 602 is provided on the bottom surface of the top plate 6, and a second ear plate 301 is provided on the upper end of the inclined pile 3. The second node plate 602 is connected to the second ear plate 301 by a second pin 9. The bottom surface of the top plate 6 is set at an angle to the length direction of the inclined pile 3. The rigid connection between the top plate 6 and the inclined pile 3 is achieved by the second pin 9. By utilizing the structural characteristics of the pin connection, the on-site installation process of the intersection node of the top plate 6 and the inclined pile 3 is simplified, further reducing the construction difficulty and improving the assembly efficiency of the overall micro pile group foundation.

[0037] In some embodiments of this utility model, vertical holes 101 and inclined holes 102 are provided at the bottom of the foundation trench 1. Vertical piles 2 are embedded in the vertical holes 101, and inclined piles 3 are embedded in the inclined holes 102. This achieves precise positioning and installation of the vertical piles 2 and inclined piles 3, avoiding misalignment or tilting during construction. It effectively ensures that the vertical piles 2 and inclined piles 3 form a stable sub-foundation spatial truss structure at the designed angle, thereby ensuring the uniform transmission of subsequent loads. On the other hand, the construction method of pre-setting vertical holes 101 and inclined holes 102 is more suitable for the mechanized operation requirements of complex terrains such as mountainous areas, simplifying the on-site construction process, reducing the difficulty of implanting vertical piles 2 and inclined piles 3, and making the contact between vertical piles 2 and inclined piles 3 and the soil more compact. This effectively improves the pull-out and lateral resistance of vertical piles 2 and inclined piles 3, thereby strengthening the overall micro-pillar foundation's support stability for high-load, high-voltage transmission lines.

[0038] like Figure 1 and Figure 4 As shown, in some embodiments of this utility model, the gap between the vertical hole 101 and the vertical pile 2, and the gap between the inclined hole 102 and the inclined pile 3 are filled with a consolidation material 10. The consolidation material 10 is M30 mortar or fine stone concrete. By filling the gaps between the vertical hole 101 and the vertical pile 2, and between the inclined hole 102 and the inclined pile 3 with the consolidation material 10, the soil of the hole wall of the vertical pile 2 and the vertical hole 101 can be tightly bonded together, and the soil of the hole wall of the inclined pile 3 and the inclined hole 102 can be tightly bonded together. This eliminates the gap between the vertical pile 2 and the vertical hole 101, and the gap between the inclined pile 3 and the inclined hole 102, and avoids the vertical pile 2 and the inclined pile 3 from shaking or displacement under load, thereby enhancing the installation stability of the vertical pile 2 and the inclined pile 3. Meanwhile, the filling consolidation material 10 can further enhance the pull-out and lateral bearing capacity of the vertical piles 2 and the inclined piles 3, thereby improving the overall stability of the micro pile group foundation.

[0039] To address the challenges of traditional pile cap pre-embedded anchor bolts, which result in large pile cap volumes and complex, tortuous force transmission paths due to the anchorage length requirements of the pre-embedded bolts (from steel pipe to concrete, then to the pre-embedded anchor bolts, and finally to the truss 4), making concrete the critical path for force transmission at the nodes, this invention addresses these issues by providing a protective cap 7 at the top plate 6 in some embodiments. This protective cap 7, formed by pouring concrete at the top plate 6, provides comprehensive protection for the top plate 6 and its steel connecting components, including the ear plates, first node plate 401, second node plate 602, first pin 8, and second pin 9. This protects against external moisture, soil acids and alkalis, and other corrosive media, preventing rust and corrosion of the steel components and extending the service life and connection reliability of the overall micro-pile foundation. In this system, concrete only serves the function of protection and rust prevention. The force transmission system is directly from truss 4 to vertical pile 2 and inclined pile 3. The force transmission path of concrete in traditional reinforced concrete pre-embedded anchor bolts is significantly reduced, which greatly reduces the requirements for concrete quality, saves costs, reduces construction difficulty, and makes force transmission simpler, effectively improving the overall lateral force resistance and bearing capacity of micro pile foundation.

[0040] In some embodiments of this utility model, soil is backfilled into the foundation trench 1, and the soil is level with the ground surface. By backfilling the foundation trench 1 with soil and smoothing it to be level with the ground surface, an external soil covering and protection can be formed for the vertical piles 2, inclined piles 3, and various connecting components within the foundation trench 1, reducing the erosion of the foundation structure by the external environment. At the same time, the lateral pressure of the backfill soil enhances the embedment effect between the micro-pile foundation and the surrounding soil, further improving the overall stability of the micro-pile foundation. Moreover, the treatment of backfilling to be level with the ground surface can quickly restore the topography of the construction area, avoiding topographical undulations caused by the foundation trench 1 and reducing the damage to the terrain caused by construction.

[0041] In addition to the aforementioned micro-pile foundation, this utility model also provides a power transmission line that includes the micro-pile foundation disclosed in the above embodiments. For the structure of other parts of the power transmission line, please refer to the prior art, which will not be repeated here.

[0042] In summary, by combining vertical piles and inclined piles 3 to form a sub-foundation spatial truss structure, the overall lateral force resistance and bearing capacity of the micro pile group foundation are effectively improved, making it suitable for straight towers with large loads or large-angle iron towers with large horizontal forces. This greatly expands the application scenarios of micro pile group foundations and enables large-scale application.

[0043] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0044] This article uses specific examples to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of this utility model.

Claims

1. A micro-pillar foundation for supporting the legs of a steel tower, characterized in that, include: The foundation trench (1) and vertical piles (2) and inclined piles (3) are set at an angle in the foundation trench (1). The vertical piles (2) are connected to the inclined piles (3), and the upper end of the vertical piles (2) is connected to the truss (4). The upper end of the truss (4) is provided with a tower foot plate (5) for connecting the tower legs.

2. A micro-pile foundation according to claim 1, characterized in that, Four vertical piles (2) are set in the foundation trench (1), and each vertical pile (2) is connected to two or more inclined piles (3).

3. A micro-pile foundation according to claim 1 or 2, characterized in that, The upper end of the vertical pile (2) is provided with a top plate (6), which is connected to the lower end of the truss (4) and the upper end of the inclined pile (3).

4. A micro-pile foundation according to claim 3, characterized in that, The top surface of the top plate (6) is provided with a first ear plate (601), and the lower end of the truss (4) is provided with a first node plate (401). The first ear plate (601) is connected to the first node plate (401) by a first pin (8).

5. A micro-pile foundation according to claim 4, characterized in that, The bottom surface of the top plate (6) is provided with a second node plate (602), and the upper end of the inclined pile (3) is provided with a second ear plate (301). The second node plate (602) is connected to the second ear plate (301) by a second pin (9).

6. A micro-pile foundation according to claim 1 or 2, characterized in that, The bottom of the foundation trench (1) is provided with a vertical hole (101) and an inclined hole (102). A vertical pile (2) is embedded in the vertical hole (101) and an inclined pile (3) is embedded in the inclined hole (102).

7. A micro-pile foundation according to claim 6, characterized in that, The gap between the vertical hole (101) and the vertical pile (2) and the gap between the inclined hole (102) and the inclined pile (3) are filled with consolidation material (10), which is M30 mortar or fine stone concrete.

8. A micro-pile foundation according to claim 3, characterized in that, A protective cap (7) is provided at the position of the top plate (6).

9. A micro-pile foundation according to claim 8, characterized in that, The trench (1) is backfilled with soil material, and the soil material is flush with the ground surface.

10. A power transmission line, characterized in that, The micro-pile foundation includes any one of claims 1-9 above.

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