Raft foundation for frame column of underground auxiliary workshop of hydropower station

Abstract

The invention discloses a raft foundation for a frame column of an underground auxiliary workshop of a hydropower station in the technical field of hydropower engineering structures, which comprises a bottom plate and a frame column embedding section, the frame column embedding section is embedded into the bottom plate, a frame column punching damage surface extending from the upper surface of the bottom plate to the inside of the bottom plate is formed in the bottom plate, and the raft foundation further comprises an anti-punching seat, the anti-punching seat is formed by at least three anti-punching units in a surrounding mode, the anti-punching seat is arranged outside the embedded section of the frame column in a sleeving mode and embedded into the bottom plate, each anti-punching unit is provided with a front anti-punching plate, the front anti-punching plates are perpendicular to the punching damage face of the frame column, and the plane where the punching damage face of the frame column is located intersects with the front anti-punching plates. The raft foundation solves the technical problems that an existing raft foundation is large in thickness, the excavation depth of a foundation pit is increased, and the cost is high, the thickness of the raft foundation is reduced, the excavation depth of the foundation pit is reduced, and the punching resistance is improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydropower engineering structures, and in particular to a raft foundation for frame columns of underground auxiliary powerhouses of hydropower stations. Background Art

[0002] The upper part of the underground auxiliary powerhouse of a hydropower station is generally a frame structure, and the bottom is generally a raft foundation. The raft foundation includes a bottom plate and a frame column embedded section. The frame column embedded section is embedded in the bottom plate, and a frame column shear failure surface extending from the upper surface of the bottom plate to the inside of the bottom plate is formed in the bottom plate. In the design and construction of the underground auxiliary powerhouse of a hydropower station, in order to support heavy machinery and equipment and ensure structural stability, the traditional raft foundation design often requires a thicker bottom plate to ensure that the raft foundation has sufficient bearing capacity and resistance to shear failure. Although this design method is effective, it has some obvious limitations and challenges, including:

[0003] Thick bottom slab: Due to the heavy load on the building, the raft foundation is usually designed to be very thick to ensure sufficient shear strength. This thickness is generally between 1.5m and 2.5m, which not only increases the material cost, but also makes the construction complicated and time-consuming.

[0004] Increased excavation depth of foundation pit: The thickness of the raft foundation requires that the foundation pit must be dug deeper, which further increases the workload of earth excavation and may bring about a series of additional engineering problems such as groundwater treatment and slope stability.

[0005] The overall construction cost is high: the increase in the thickness of the raft foundation and the depth of the foundation pit excavation directly leads to an increase in the amount of materials used. Coupled with the more complicated construction process, the construction cost of the entire project ultimately increased significantly. Summary of the invention

[0006] In order to solve the technical problems of large thickness of existing raft foundation, increased excavation depth of foundation pit and high cost, the present invention provides a raft foundation for frame columns of underground auxiliary powerhouse of hydropower station, which reduces the thickness of raft foundation, reduces the excavation depth of foundation pit and improves the shear resistance.

[0007] The technical solution adopted by the present invention to solve its technical problem is:

[0008] The raft foundation for frame columns of underground auxiliary powerhouses of hydropower stations comprises a bottom plate and a frame column embedded section, wherein the frame column embedded section is embedded in the bottom plate, and a frame column shear failure surface extending from the upper surface of the bottom plate to the inside of the bottom plate is formed in the bottom plate. The raft foundation also comprises a shear resistance seat, which is surrounded by at least three shear resistance units, and the shear resistance seat is sleeved outside the frame column embedded section and embedded in the bottom plate, and the shear resistance unit has a front shear resistance plate, which is perpendicular to the frame column shear failure surface, and the plane where the frame column shear failure surface is located intersects with the front shear resistance plate.

[0009] Furthermore, the anti-punching shear unit also includes two side anti-punching shear plates, which are respectively located on the two opposite sides of the front anti-punching shear plate in the length direction. The two side anti-punching shear plates are inclined to the vertical line on the upper surface of the front anti-punching shear plate. The anti-punching shear unit presents an open expansion shape, and the opening faces the shear failure surface of the frame column.

[0010] Furthermore, the included angle between the side anti-punching plate and the front anti-punching plate is 120° to 160°.

[0011] Furthermore, the front anti-punching shear plates of two adjacent anti-punching shear units are fixed by welding, and the side anti-punching shear plates of two adjacent anti-punching shear units are fixed by welding.

[0012] Furthermore, the anti-punching seat is formed by four anti-punching units, the side anti-punching plates of two adjacent anti-punching units are connected correspondingly, and the side anti-punching plates of the four anti-punching units are surrounded to form a closed loop.

[0013] Furthermore, the central axis of the anti-punching seat coincides with the central axis of the embedded section of the frame column.

[0014] Furthermore, the front anti-punching plate is a steel plate.

[0015] Furthermore, the anti-punching shear unit also includes a first group of steel nails and a second group of steel nails. The first group of steel nails is located on the upper surface of the front anti-punching shear plate close to the shear failure surface of the frame column, and the second group of steel nails is located on the lower surface of the front anti-punching shear plate away from the shear failure surface of the frame column. The first group of steel nails includes at least one row of steel nails arranged at intervals along the length direction of the front anti-punching shear plate, and the second group of steel nails includes at least two rows of steel nails arranged at intervals along the length direction of the front anti-punching shear plate.

[0016] Furthermore, the first group of steel nails is perpendicular to the upper surface of the front anti-punching shear plate, and the second group of steel nails is perpendicular to the lower surface of the front anti-punching shear plate.

[0017] Furthermore, the first steel nail group includes a row of steel nails arranged at intervals along the length direction of the front anti-punching shear plate, and the second steel nail group includes two rows of steel nails arranged at intervals along the length direction of the front anti-punching shear plate. The central axis of the steel nails in the first steel nail group coincides with the shear failure surface of the frame column, and the two rows of steel nails in the second steel nail group are separated on both sides of the plane where the shear failure surface of the frame column is located.

[0018] The beneficial effects of the present invention are:

[0019] 1. Reduce the thickness of the base plate: By introducing a shear-resistant seat to enhance the bearing capacity of the local area and blocking the shear-resistant damage path of the frame column in the base plate, the overall thickness of the base plate can be reduced, thereby saving material costs.

[0020] Reduce the excavation depth of the foundation pit: The reduction in the thickness of the bottom plate means that the excavation depth of the foundation pit can also be reduced accordingly, reducing the workload of earth excavation and related engineering problems.

[0021] Improve shear resistance: The setting of shear resistance seat enhances the ability of raft foundation to resist shear damage of frame columns, ensuring structural safety.

[0022] 2. Further enhance the anti-punching ability: the open expansion design can better disperse and resist loads from different directions, and improve the anti-punching performance of the overall structure. Improve structural stability: the skewed side wing anti-punching plate helps to improve the overall stability and rigidity of the structure.

[0023] 3. Angle between the side anti-punch shear plate and the front anti-punch shear plate

[0024] Optimized punching resistance performance: The design within a specific angle range enables the side wing punching resistance plate to maintain good structural performance while resisting loads and avoid excessive stress concentration.

[0025] 4. Welding fixation between anti-punching units

[0026] Enhance structural integrity: Welding fixation can ensure that each anti-shear unit is closely connected, improving the integrity and durability of the structure.

[0027] 5. Closed loop formed by four anti-punching units

[0028] Since the cross-section of the frame column is generally square, the structure formed by the four shear-resistant units can better correspond to the four sides of the frame column, better disperse the load, and improve the stability of the overall structure.

[0029] 6. The shear-resistant seat coincides with the central axis of the embedded section of the frame column

[0030] This design ensures that the anti-punching shear seat is aligned with the embedded section of the frame column, improves the accuracy and reliability of the structure, and ensures balanced force on the anti-punching shear seat.

[0031] 7. The front anti-punching plate is a steel plate. On the one hand, the steel plate has high strength, impact resistance and corrosion resistance, which can improve the anti-punching performance. On the other hand, the steel plate has low cost and high cost performance.

[0032] 8. Setting of Steel Nail Group

[0033] Increase the shear resistance performance: The setting of the steel nail group can enhance the bonding force between the shear resistance seat and the base plate, so that the shear resistance seat can block the shear resistance damage path of the frame column in the base plate and improve the shear resistance of the structure.

[0034] Improve structural integrity: The steel nail group helps to combine the anti-punching seat and the base plate more firmly, thereby enhancing the integrity of the structure.

[0035] 9. Arrangement of steel nail groups

[0036] Optimize the anti-shearing effect: The vertical arrangement of the steel nail group can maximize its anchoring effect and improve the structure's ability to resist shearing damage.

[0037] 10. Specific arrangement of steel nail groups

[0038] Precisely align with the shear failure surface of the frame column: the first group of steel nails coincides with the shear failure surface of the frame column, and the second group of steel nails is separated on both sides. The design can more effectively resist shear failure and ensure the safety and stability of the structure.

[0039] In summary, these design improvements work together to significantly improve the structural performance of the frame column raft foundation of the underground auxiliary powerhouse of the hydropower station, while reducing the cost and construction difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of a raft foundation for frame columns of an underground auxiliary powerhouse of a hydropower station according to the present invention;

[0041] Figure 2 It is a structural schematic diagram of the raft foundation of the prior art;

[0042] Figure 3 It is a structural schematic diagram of the anti-punching seat;

[0043] Figure 4 It is a top view of the punching shear seat;

[0044] Figure 5 It is a side view of the punching shear resistance seat;

[0045] Figure 6 It is a structural schematic diagram of the punching shear resistance unit;

[0046] Figure 7 It is a structural schematic diagram of the anti-punching shear unit from another perspective;

[0047] Figure 8 is the cross-sectional view of the punching shear unit;

[0048] Marked in the figure are, 1-bottom plate, 2-frame column embedded section, 3-frame column shear failure surface, 4-shear resistance seat, 5-shear resistance unit, 51-front shear resistance plate, 52-side shear resistance plate, 53-first steel nail group, 54-second steel nail group. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the embodiments of the present application more clearly expressed, the present invention is further described below in conjunction with the accompanying drawings.

[0050] First of all, it needs to be stated that the technical solutions of the embodiments of the present application are clearly and completely described. The described embodiments are part of the embodiments of the present application, and are not limitations of the present invention. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0051] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “first”, “second”, “upper”, “lower”, “left”, “right”, “inner”, “outer”, “axial” or “radial” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention. They are not intended to indicate or imply that the device or element referred to must have a specific orientation structure and operation, and therefore cannot be understood as a limitation on the present invention.

[0052] It should be noted that, in the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] Reference Figures 1 to 8 The present invention provides a raft foundation for frame columns of underground auxiliary powerhouses of hydropower stations.

[0054] The present invention aims to block the shear failure path of the upper frame column embedded section 2 in the bottom plate 1 through an innovative design scheme, thereby effectively reducing the thickness required for the raft foundation while maintaining or improving its shear resistance. Specifically, this goal will be achieved by adding a shear resistance seat 4 at a specific position in the bottom plate 1, thereby changing the shear failure mode and improving the overall shear resistance of the raft foundation. Such a design can not only reduce the burden on the bottom plate 1, but also reduce the depth of foundation pit excavation, thereby reducing construction difficulty and cost, and improving the economy and construction efficiency of the entire hydropower station underground auxiliary powerhouse project.

[0055] like Figure 1 and Figure 6As shown, this embodiment proposes a raft foundation for the frame columns of the underground auxiliary powerhouse of a hydropower station, comprising a bottom plate 1 and a frame column embedded section 2, the frame column embedded section 2 is embedded in the bottom plate 1, a frame column shear failure surface 3 extending from the upper surface of the bottom plate 1 to the inside of the bottom plate 1 is formed in the bottom plate 1, and also includes an anti-shear seat 4, the anti-shear seat 4 is surrounded by at least three anti-shear units 5, the anti-shear seat 4 is sleeved outside the frame column embedded section 2 and embedded in the bottom plate 1, the anti-shear unit 5 has a front anti-shear plate 51, the front anti-shear plate 51 is perpendicular to the frame column shear failure surface 3, and the plane where the frame column shear failure surface 3 is located intersects with the front anti-shear plate 51.

[0056] The anti-punching seat 4 is formed by at least three anti-punching units 5 , which means that the number of the anti-punching units 5 can be 3, 4, 5 or more than 5.

[0057] The positive anti-punching shear plate 51 is preferably a steel plate, and other fiber-reinforced composite materials, other alloy materials or steel mesh plates can also be used, as long as it can resist the punching shear force generated by the embedded section 2 of the frame column in the base plate 1.

[0058] like Figure 2 As shown, the upper part of the underground auxiliary powerhouse of the prior art hydropower station is generally a frame structure, and the bottom generally adopts a raft foundation, which includes a bottom plate 1 and a frame column embedded section 2, and the frame column embedded section 2 is embedded in the bottom plate 1, and a frame column punching failure surface 3 extending from the upper surface of the bottom plate 1 to the inside of the bottom plate 1 is formed in the bottom plate 1. The traditional raft foundation design often requires a thicker bottom plate 1 to ensure that the raft foundation has sufficient bearing capacity and resistance to shear failure. Although this design method is effective, it has some obvious limitations and challenges, including a thicker bottom plate 1, an increased foundation pit excavation depth, and high overall construction costs.

[0059] like Figure 1 , Figure 6 , Figure 7 and Figure 8 As shown, in some embodiments, the anti-punching shear unit 5 also includes two side anti-punching shear plates 52, which are respectively located on two opposite sides of the front anti-punching shear plate 51 in the length direction, and the two side anti-punching shear plates 52 are inclined to the vertical line of the upper surface of the front anti-punching shear plate 51. The anti-punching shear unit 5 is in an open expansion shape, and the opening is facing the shear failure surface 3 of the frame column.

[0060] The two side anti-punching plates 52 are located on two opposite sides of the length direction of the front anti-punching plate 51. Preferably, the length of the side anti-punching plates 52 is consistent with the length of the side of the front anti-punching plate 51, or it can be shorter than the length of the side of the front anti-punching plate 51, as long as it can have a certain anti-punching effect. The anti-punching unit 5 is in an open expansion shape, and the expansion angle is not particularly limited. Preferably, the angle between the side anti-punching plates 52 and the front anti-punching plate 51 is 120° to 160°.

[0061] like Figure 8 As shown, in some embodiments, the angle between the side anti-punching plate 52 and the front anti-punching plate 51 is 120° to 160°.

[0062] In some embodiments, the front anti-punching shear plates 51 of two adjacent anti-punching shear units 5 are fixed by welding, and the side anti-punching shear plates 52 of two adjacent anti-punching shear units 5 are fixed by welding. The structural integrity of the anti-punching shear seat 4 is enhanced by welding, and the welding fixation can ensure that each anti-punching shear unit 5 is closely connected, improve the integrity and durability of the structure, so that the front anti-punching shear plate 51 is enclosed into a closed loop, and the side anti-punching shear plate 52 is enclosed into a closed loop, thereby improving the overall anti-punching performance and structural strength.

[0063] like Figure 3 and Figure 4 As shown, in some embodiments, the anti-punching seat 4 is formed by four anti-punching units 5, and the side anti-punching plates 52 of two adjacent anti-punching units 5 are connected correspondingly, and the side anti-punching plates 52 of the four anti-punching units 5 are surrounded to form a closed loop. Since the cross-section of the frame column embedded section 2 is generally square, the structure formed by the four anti-punching units 5 can better correspond to the four faces of the frame column embedded section 2, better disperse the load, and improve the stability of the overall structure.

[0064] like Figure 4 As shown, in some embodiments, the central axis of the anti-punching seat 4 coincides with the central axis of the frame column embedded section 2. This design ensures that the anti-punching seat 4 is aligned with the frame column embedded section 2, improves the accuracy and reliability of the structure, ensures that the force of the anti-punching seat 4 is balanced, makes the load of the frame column embedded section 2 on the anti-punching seat 4 in all directions tend to be consistent, makes the force of each position of the anti-punching seat 4 balanced, and improves the service life of the device.

[0065] In some embodiments, the front anti-punching plate 51 is a steel plate. The steel plate is selected here because the steel plate has high strength, impact resistance and corrosion resistance, can improve the anti-punching performance, and the steel plate has low cost and high cost performance.

[0066] like Figure 5 , Figure 6 , Figure 7 and Figure 8As shown, in some embodiments, the anti-punching shear unit 5 also includes a first steel nail group 53 and a second steel nail group 54. The first steel nail group 53 is located on the upper surface of the front anti-punching shear plate 51 close to the punching shear failure surface 3 of the frame column, and the second steel nail group 54 is located on the lower surface of the front anti-punching shear plate 51 away from the punching shear failure surface 3 of the frame column. The first steel nail group 53 includes at least one row of steel nails arranged at intervals along the length direction of the front anti-punching shear plate 51, and the second steel nail group 54 includes at least two rows of steel nails arranged at intervals along the length direction of the front anti-punching shear plate 51.

[0067] Here, the first steel nail group 53 and the second steel nail group 54 can be respectively perpendicular to the front anti-punching plate 51, or can be inclined at a certain angle, which is not particularly limited here. Their function is to improve the overall bonding between the anti-punching seat 4 and the base plate 1.

[0068] like Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, in some embodiments, the first steel nail group 53 is perpendicular to the upper surface of the front anti-punching shear plate 51, and the second steel nail group 54 is perpendicular to the lower surface of the front anti-punching shear plate 51. This design optimizes the anti-punching shear effect, and the vertical arrangement of the first steel nail group 53 and the second steel nail group 54 can maximize their anchoring effect and improve the ability of the structure to resist punching shear damage.

[0069] like Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, in some embodiments, the first steel nail group 53 includes a row of steel nails spaced apart along the length direction of the front anti-punching shear plate 51, and the second steel nail group 54 includes two rows of steel nails spaced apart along the length direction of the front anti-punching shear plate 51. The central axis of the steel nails of the first steel nail group 53 coincides with the punching shear failure surface 3 of the frame column, and the two rows of steel nails of the second steel nail group 54 are separated on both sides of the plane where the punching shear failure surface 3 of the frame column is located. The design that the first steel nail group 53 is precisely aligned with the punching shear failure surface 3 of the frame column, that is, the first steel nail group 53 coincides with the punching shear failure surface 3 of the frame column, and the second steel nail group 54 is separated on both sides can more effectively resist punching shear failure and ensure the safety and stability of the structure.

Claims

1. A raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station, comprising a bottom plate (1) and a frame column embedded section (2), wherein the frame column embedded section (2) is embedded in the bottom plate (1), and a frame column shear failure surface (3) extending from the upper surface of the bottom plate (1) to the inside of the bottom plate (1) is formed in the bottom plate (1), wherein: It also comprises an anti-shear seat (4), which is formed by at least three anti-shear units (5), the anti-shear seat (4) is sleeved outside the frame column embedded section (2) and embedded in the bottom plate (1), the anti-shear unit (5) has a front anti-shear plate (51), the front anti-shear plate (51) is perpendicular to the frame column shear failure surface (3), and the plane where the frame column shear failure surface (3) is located intersects with the front anti-shear plate (51).

2. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 1 is characterized by: The anti-punching shear unit (5) further comprises two side anti-punching shear plates (52), the two side anti-punching shear plates (52) being respectively located at two opposite sides of the front anti-punching shear plate (51) in the length direction, the two side anti-punching shear plates (52) being inclined to a vertical line on the upper surface of the front anti-punching shear plate (51), and the anti-punching shear unit (5) presents an open expansion shape, with the opening facing the punching shear failure surface (3) of the frame column.

3. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 2 is characterized by: The included angle between the side anti-punching plate (52) and the front anti-punching plate (51) is 120° to 160°.

4. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 2 is characterized by: The front anti-punching shear plates (51) of two adjacent anti-punching shear units (5) are fixed by welding, and the side anti-punching shear plates (52) of two adjacent anti-punching shear units (5) are fixed by welding.

5. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 2, characterized in that: The anti-punching seat (4) is formed by enclosing four anti-punching units (5), the side wing anti-punching plates (52) of two adjacent anti-punching units (5) are correspondingly connected, and the side wing anti-punching plates (52) of the four anti-punching units (5) are enclosed to form a closed loop.

6. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 1, characterized in that: The central axis of the anti-punching seat (4) coincides with the central axis of the frame column embedded section (2).

7. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 1, characterized in that: The front anti-shearing plate (51) is a steel plate.

8. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in any one of claims 1 to 7, characterized in that: The anti-punching shear unit (5) further comprises a first steel nail group (53) and a second steel nail group (54); the first steel nail group (53) is located on the upper surface of the front anti-punching shear plate (51) on the side close to the punching shear failure surface (3) of the frame column, and the second steel nail group (54) is located on the lower surface of the front anti-punching shear plate (51) on the side away from the punching shear failure surface (3) of the frame column; the first steel nail group (53) comprises at least one row of steel nails arranged at intervals along the length direction of the front anti-punching shear plate (51), and the second steel nail group (54) comprises at least two rows of steel nails arranged at intervals along the length direction of the front anti-punching shear plate (51).

9. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 8, characterized in that: The first steel nail group (53) is perpendicular to the upper surface of the front anti-punching shear plate (51), and the second steel nail group (54) is perpendicular to the lower surface of the front anti-punching shear plate (51).

10. The raft foundation for frame columns of underground auxiliary powerhouses of a hydropower station as claimed in claim 9, characterized in that: The first steel nail group (53) comprises a row of steel nails arranged at intervals along the length direction of the front anti-punching shear plate (51), and the second steel nail group (54) comprises two rows of steel nails arranged at intervals along the length direction of the front anti-punching shear plate (51). The central axes of the steel nails of the first steel nail group (53) coincide with the punching shear failure surface (3) of the frame column, and the two rows of steel nails of the second steel nail group (54) are located on both sides of the plane where the punching shear failure surface (3) of the frame column is located.

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