Arch dam foundation unfavorable structural zone processing structure

Abstract

The utility model belongs to the technical field of water conservancy and hydropower engineering, and particularly relates to a structure for treating unfavorable structural zones of an arch dam foundation, which is suitable for dam foundation treatment design and construction projects when the arch dam foundation encounters the unfavorable structural zones such as wide cracks, faults, soft zones, crushed zones and the like. The utility model solves the problem that the excavation work amount and the filling work are increased due to the adoption of a treatment mode of foundation deep excavation and concrete plug backfilling for unfavorable structural belts. The treatment structure for the unfavorable tectonic zone of the arch dam foundation relates to an arch dam built on bedrock, the unfavorable tectonic zone including joints, cracks, fault fracture zones, soft zones or strong karst zones exists in the bedrock, and an arch dam body is arranged above the unfavorable tectonic zone. The treatment structure includes an arched base across the unfavorable construction zone and a stable support structure above the arched base; anchoring structures are arranged at the arch ends of the two ends of the arch-shaped base and used for fixing the arch-shaped base to the bed rock.

Description

Technical Field

[0001] This utility model belongs to the field of water conservancy and hydropower engineering technology, specifically relating to a structure for treating unfavorable structural zones in arch dam foundations. It is applicable to the design and construction of dam foundation treatment projects when arch dam foundations encounter unfavorable structural zones such as wide fissures, faults, weak zones, and fractured zones. Background Technology

[0002] Arch dams are characterized by their economy, safety, and superior performance. With the development of dam construction technology, hydropower energy, and large-scale hydropower stations, arch dams have gradually become a common type of dam in modern water conservancy and hydropower engineering. As the most critical main structure in water conservancy and hydropower construction, the consequences of a dam failure are extremely serious, causing not only huge economic losses but also potentially endangering the lives of downstream residents. The dam foundation typically bears enormous loads from the dam body and its own complex load conditions; therefore, the stability of the dam body and foundation is crucial to dam safety, especially when the arch dam is high, placing even stricter requirements on the foundation.

[0003] In engineering practice, natural foundations always possess varying degrees of defects. The surface and shallow rock masses of dam foundations are easily weathered and fractured under geological processes. Even fresh rock masses may contain various joints, fissures, and fault fracture zones due to geological processes such as tectonic movements, magmatism, metamorphism, and earthquakes. Therefore, in practical engineering, natural foundations must be treated before they can be used as arch dam foundations. Arch dams often demonstrate their stringent requirements for the foundation through indicators such as stress, deformation, and stability safety. For foundations with complex conditions, the design stress intensity, deformation, and stability may not meet the specifications. This necessitates specific engineering measures to improve the stress and stability conditions of the dam body.

[0004] When encountering unfavorable structural zones in the foundation conditions of arch dams, deep excavation and the installation of concrete rock plugs are often used to improve the stress, displacement distribution, and stability of the dam body. This approach is suitable for smaller unfavorable structural zones. However, when the unfavorable structural zones are large and deep, deep excavation and the installation of concrete rock plugs increase the amount of rock excavation and backfilling work required for the dam foundation. At deeper excavations, adverse construction conditions such as water inrush and high slopes may occur, significantly increasing the workload, construction period, and investment. Therefore, for arch dams with unfavorable structural zones in the bedrock beneath the foundation, a more reasonable foundation treatment scheme is needed to address the increased workload, construction period, and investment caused by conventional deep excavation and concrete rock plugs due to joints, fissures, fault fracture zones, and other unfavorable structural zones in the dam foundation. Utility Model Content

[0005] In view of this, this utility model discloses a structure for treating unfavorable structural zones in the foundation of an arch dam. By setting an arched base, a stable support structure, and an anchoring mechanism, the safety and stability of the overall structure of the arch dam are achieved, solving the problem of increased excavation and filling work caused by using deep foundation excavation and concrete rock plugs to treat unfavorable structural zones.

[0006] The unfavorable structural zone treatment structure for the arch dam foundation involves an arch dam built on bedrock, where there are unfavorable structural zones including joints, fissures, fault fracture zones, weak zones or strong karst zones, and the arch dam body is located above the unfavorable structural zones. The treatment structure includes an arched base spanning the unfavorable structural zones and a stable support structure above the arched base.

[0007] Anchoring structures are provided at the arch ends of the arched base to fix the arched base to the bedrock.

[0008] Preferably, the stable support structure includes a pad layer horizontally disposed above the arched base, and a triangular three-dimensional structure formed by the pad layer and the bedrock surrounding both ends of the arched base;

[0009] The cushion layer is used to ensure that the foundation of the arch dam is subjected to forces in one plane.

[0010] Preferably, the subbase is made of C20 concrete with a thickness of 1 to 2 meters.

[0011] Preferably, the arched base is provided with a steel mesh to improve the structural load-bearing capacity.

[0012] Preferably, the triangular solid structure is cast using low-heat concrete to reduce temperature stress.

[0013] Preferably, the contact surface between the triangular solid structure and the arched base is roughened to prevent structural seams from forming between the triangular solid structure and the arched base.

[0014] Preferably, the anchoring structure includes an anchor rod, one end of which is fixedly connected to the arch ends of the arched base at both ends, and the other end is fixedly connected to the bedrock, so as to ensure that the arched base and the bedrock are subjected to force as a whole.

[0015] Beneficial effects

[0016] (I) The unfavorable structural zone treatment structure of the arch dam foundation of this utility model includes an arched base and a stable support structure above it, and an anchoring structure between the arch end of the arched base and the bedrock. The load transmitted by the arch dam body above the unfavorable structural zone is transferred to the bedrock on both sides of the unfavorable structural zone through the arch effect of the arched base. This can ensure the bearing capacity of the dam foundation and avoid uneven settlement and structural damage caused by insufficient bearing capacity of the dam foundation around the unfavorable structural zone.

[0017] (II) The supporting structure in the unfavorable structural zone treatment structure of the arch dam foundation of this utility model includes a cushion layer set above the arched base, which serves to level, isolate, and transition. Furthermore, by adjusting the thickness of the cushion layer, errors in bedrock excavation are compensated for, ensuring that the arch dam foundation is stressed on a single plane, facilitating construction layout and the erection of structural formwork.

[0018] (III) The supporting structure in the unfavorable structural zone treatment structure of the arch dam foundation of this utility model also includes a triangular three-dimensional structure formed by the arch base, the cushion layer, and the bedrock on both sides. This triangular three-dimensional structure is cast with low-heat concrete to reduce the temperature stress of the unfavorable structural zone treatment structure.

[0019] (iv) In the unfavorable structural zone treatment structure of the arch dam foundation of this utility model, steel mesh is set on the arch base to improve the stress capacity of the arch base structure and ensure the safety of the arch dam.

[0020] (v) The unfavorable structural zone treatment structure of the arch dam foundation of this utility model adopts anchor rods as anchoring structure to fix the arch base to the bedrock on both sides, so as to ensure the overall stress of the arch base and the bedrock and improve the stability of the dam foundation structure above the unfavorable structural zone. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of the unfavorable structural zone treatment structure of the arch dam foundation according to this utility model;

[0022] Figure 2 for Figure 1 Large detail view of point A in the middle.

[0023] Among them, 1-overburden, 2-bedrock, 3-dam body, 4-unfavorable structural zone, 5-arched base, 6-triangular three-dimensional structure

[0024] 7-Subbase, 8-Anchor bolt, 9-Reinforcing mesh. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings. It should be emphasized that the embodiments described in the present invention are illustrative and not limiting. Therefore, the present invention is not limited to the embodiments described in the specific embodiments. Any other embodiments derived by those skilled in the art based on the technical solution of the present invention are also within the scope of protection of the present invention.

[0026] like Figure 1-2 As shown, according to the design requirements of the arch dam foundation bearing capacity, the overburden layer 1 above the arch dam foundation is removed, and the lower bedrock 2 is excavated to a certain depth. For the arch dam foundation with various unfavorable structural zones 4 such as joints, fissures, fault fracture zones, weak zones, or strong karst zones exposed during excavation, targeted treatment of the unfavorable structural zones 4 is required.

[0027] The present invention relates to an arch dam constructed on bedrock 2, wherein there is an unfavorable structural zone 4 within the bedrock 2, and the arch dam body 3 is located above the unfavorable structural zone 4.

[0028] This utility model discloses a structure for treating unfavorable structural zones in the foundation of an arch dam. It includes an arched base 5 spanning an unfavorable structural zone 4 and a stable support structure above the arched base 5. Anchoring structures are provided at the arched ends of the arched base 5 to fix it to the bedrock 2. The arched base 5 in this structure can transfer the load transmitted by the dam body 3 to the intact bedrock 2 on both sides of the unfavorable structural zone 4 through the arch effect of the arched base 5, ensuring the bearing capacity of the dam body 3 foundation and preventing uneven settlement and structural damage caused by insufficient bearing capacity of the dam foundation at the unfavorable structural zone 4. Furthermore, the arched base 5 not only ensures the safety and stability of the overall arch dam structure but also reduces the physical and mechanical parameter requirements of the foundation surface in the unfavorable structural zone 4 area, avoiding the increased excavation and filling work caused by deep excavation of the foundation in the unfavorable structural zone 4. It also avoids unfavorable construction conditions such as pit water inflow and high slopes, reducing construction difficulty, accelerating the construction period, and reducing project investment.

[0029] As an example, the arched base 5 is made of concrete with a strength grade of not less than C25. When the structural dimensions of the arched base 5 exceed the set requirements, such as being greater than 2m, micro-expansion concrete can be used to avoid structural cracking.

[0030] As an example, under the load on the upper part of the dam body 3, according to the stress condition of the arched base 5, a steel mesh 9 is set inside the arched base 5 to improve the structural stress capacity of the arched base 5 and ensure the safety and stability of the overall structure of the upper dam body 3.

[0031] As an example, the stable support structure includes a horizontally positioned cushion layer 7 above the arched base 5, and a triangular three-dimensional structure 6 formed at the top of both ends of the arched base 5 and surrounded by the cushion layer 7 and bedrock 2. The triangular three-dimensional structure 6 and the arched base 5 form an integral structure, ensuring that the load transmitted by the arch dam is borne by the triangular three-dimensional structure 6 and the arched base 5 as a whole, and that the load is transferred to the good bedrock 2 on both sides of the unfavorable structural zone. The cushion layer 7 serves to level, isolate, and transition the structure. Adjusting the thickness of the cushion layer 7 compensates for errors in the excavation of the bedrock 2, ensuring that the dam foundation is stressed on a single plane, while also facilitating construction layout and the erection of structural formwork.

[0032] Regarding the triangular solid structure 6, it can be cast using low-heat concrete to reduce temperature stress. The contact surface between the triangular solid structure 6 and the arched base 5 is roughened to prevent structural joints from forming between them, ensuring that the unfavorable structural zone treatment structure of the arch dam foundation can bear the load as a whole.

[0033] As an example, the subbase 7 is made of C20 concrete and has a thickness of 1 to 2 m.

[0034] Regarding the anchoring structure, it includes an anchor rod 8, one end of which is fixedly connected to the arch ends of the arch base 5, and the other end is fixedly connected to the bedrock 2, in order to ensure that the arch base 5 and the bedrock 2 are subjected to force as a whole, and to ensure the stability of the overall structure of the arch dam.

[0035] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A structure for treating unfavorable structural zones in the foundation of an arch dam, relating to an arch dam constructed on bedrock (2), wherein the bedrock (2) contains unfavorable structural zones (4) including joints, fissures, fault fracture zones, weak zones, or strong karst zones, and the arch dam body (3) is situated above the unfavorable structural zones (4), characterized in that, The treatment structure includes an arched base (5) spanning the unfavorable structural zone (4) and a stable support structure above the arched base (5); Anchoring structures are provided at the arch ends of the arch base (5) to fix the arch base (5) to the bedrock (2).

2. The structure for treating unfavorable structural zones in the foundation of an arch dam according to claim 1, characterized in that, The stable support structure includes a pad (7) horizontally disposed above the arched base (5), and a triangular three-dimensional structure (6) formed above both ends of the arched base (5) and surrounded by the pad (7) and the bedrock (2); The cushion layer (7) is used to ensure that the foundation of the arch dam is subjected to forces in one plane.

3. The structure for treating unfavorable structural zones in the foundation of an arch dam according to claim 2, characterized in that, The cushion layer (7) is made of C20 concrete and has a thickness of 1 to 2 m.

4. The structure for treating unfavorable structural zones in the foundation of an arch dam according to claim 1, characterized in that, The arched base (5) is provided with steel mesh (9) to improve the structural load-bearing capacity.

5. The structure for treating unfavorable structural zones in the foundation of an arch dam according to claim 2, characterized in that, The triangular solid structure (6) is cast with low-heat concrete to reduce temperature stress.

6. The structure for treating unfavorable structural zones in the foundation of an arch dam according to claim 5, characterized in that, The contact surface between the triangular solid structure (6) and the arched base (5) is roughened to prevent structural seams from forming between the triangular solid structure (6) and the arched base (5).

7. A structure for treating unfavorable structural zones in the foundation of an arch dam according to any one of claims 1-6, characterized in that, The anchoring structure includes an anchor rod (8), one end of which is fixedly connected to the arch ends of the arch base (5) and the other end is fixedly connected to the bedrock (2) to ensure that the arch base (5) and the bedrock (2) are subjected to force as a whole.

Images