Concrete face rockfill dam structure with a basic grouting gallery and its construction method

Abstract

The present invention relates to a concrete face rockfill dam structure with a foundation grouting gallery and a construction method thereof. The object of the present invention is to provide a concrete face rockfill dam structure with a foundation grouting gallery and a construction method thereof, so that the dam can also carry out foundation curtain grouting reinforcement treatment under the condition of limited water level reduction or even without reducing the operating water level. The technical solution of the present invention is: a concrete face rockfill dam structure with a foundation grouting gallery, characterized in that: the toe slab structure on the upstream surface of the concrete face rockfill dam is divided into a foundation grouting gallery structure body corresponding to the riverbed and the low elevation areas on both banks and an onshore toe slab corresponding to the high elevation areas on both banks; the grouting gallery in the foundation grouting gallery structure body is connected to the outside of the downstream dam body of the concrete face rockfill dam through a traffic gallery on both banks. The present invention is applicable to earth-rock dam projects.

Description

Technical Field

[0001] The present invention relates to a concrete face rockfill dam structure with a foundation grouting gallery and a construction method thereof, which is applicable to earth-rock dam projects. Background Art

[0002] The concrete face rockfill dam can make full use of the building excavation materials and is one of the economic and green dam types, which is widely used in the construction of hydropower and water conservancy projects in China. The dam body of the concrete face rockfill dam uses a concrete face for seepage prevention, and the foundation uses curtain grouting or a cut-off wall for seepage prevention. The connection between the foundation seepage prevention and the dam body seepage prevention is carried out through a toe slab.

[0003] Since the toe slab is exposed in the upstream reservoir, it is necessary to carry out the treatment of the toe slab foundation before impoundment, including consolidation grouting and curtain grouting. If it is necessary to carry out reinforcement grouting treatment on the foundation after the reservoir is impounded, the reservoir water must be emptied to expose the toe slab in the treatment area above the water surface. For a reservoir in the operation period, this will have an adverse impact on the normal operation of the reservoir. Especially when the elevation of the treatment part is relatively low, there is also a problem that the existing emptying facilities of the reservoir cannot meet the control of the inspection water level.

[0004] Foundation grouting belongs to a concealed project, and it is difficult to control the construction quality, and the possibility of defects is relatively large. Moreover, the normal service life of curtain grouting is generally lower than the design life of the dam. Even for curtain grouting with good construction quality, it is normal to carry out foundation seepage prevention reinforcement in the later stage. There is a certain contradiction between the existing concrete face rockfill dam in the foundation seepage prevention reinforcement treatment and the continuous normal operation of the reservoir. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: in view of the above problems, to provide a concrete face rockfill dam structure with a foundation grouting gallery and a construction method thereof, so that the dam can carry out the foundation curtain grouting reinforcement treatment under the condition of limited water level reduction or even without reducing the operation water level.

[0006] The technical solution adopted by the present invention is: a concrete face rockfill dam structure with a foundation grouting gallery, which is characterized in that: the toe slab structure on the upstream surface of the concrete face rockfill dam is divided into a foundation grouting gallery structure body corresponding to the riverbed and the low-elevation areas on both banks, and an onshore toe slab corresponding to the high-elevation areas on both banks;

[0007] The grouting gallery in the foundation grouting gallery structure body is connected to the outside of the downstream dam body of the concrete face rockfill dam through a traffic gallery on both banks.

[0008] A water stop structure I is provided at the structure joint I of the foundation grouting gallery structure body; there is a structure joint II between the foundation grouting gallery structure body and the onshore toe slab, and a water stop structure II is provided corresponding to the structure joint II.

[0009] The water stop structure I includes copper sheet water stop I and surface bulge type water stop I;

[0010] Among them, the copper sheet water stop I is located inside the foundation grouting gallery structure and on the upstream side of the grouting gallery. One end of the copper sheet water stop I is connected to the bottom copper sheet water stop of the peripheral joint on the upstream surface of the concrete face rockfill dam, and the other end extends into the bottom anchorage groove below the foundation grouting gallery structure and is anchored;

[0011] The surface bulge type water stop I is arranged across the structure joint I along the top of the foundation grouting gallery structure. One end is connected to the surface bulge type water stop on the peripheral joint to form a whole, and the other end extends into the rock anchorage groove on the upstream side rock mass of the foundation grouting gallery structure.

[0012] The water stop structure II includes copper sheet water stop II and surface bulge type water stop II;

[0013] Among them, the copper sheet water stop II is arranged across the structure joint II. The two sides of the copper sheet water stop II are respectively connected to the foundation grouting gallery structure and the onshore toe slab. One end of the copper sheet water stop II is connected to the bottom copper sheet water stop of the peripheral joint on the upstream surface of the concrete face rockfill dam, and the other end is anchored in the toe slab lower anchorage groove below the onshore toe slab;

[0014] The surface bulge type water stop II is arranged across the top of the structure joint II between the foundation grouting gallery and the onshore toe slab. One end is connected to the surface bulge type water stop of the peripheral joint to form a whole, and the other end extends into the foundation anchorage groove at the top of the upstream end of the structure joint II and the foundation grouting gallery structure.

[0015] The toe slab foundation below the onshore toe slab is provided with foundation anchor bars, consolidated grouting, and curtain grouting.

[0016] The foundation below the foundation grouting gallery structure is provided with consolidated grouting and curtain grouting.

[0017] The special cushion material is provided in the dam body of the concrete face rockfill dam on the downstream side of the peripheral joint.

[0018] Drainage ditches are provided on both sides of the bottom plate of the grouting gallery in the foundation grouting gallery structure, and pedestrian steps are provided in the part of the grouting gallery corresponding to the bank slope.

[0019] The traffic gallery adopts a concrete gallery structure embedded in the dam body of the concrete face rockfill dam. The foundation of the concrete gallery structure is located on the excavated natural foundation, and there is a transition material area with a thickness of not less than 1m between the outside of the concrete gallery structure and the dam body.

[0020] A construction method for the concrete face rockfill dam structure with a foundation grouting gallery is characterized in that:

[0021] Determine the elevation of the layout of the basic grouting gallery structure, which is the sensitive water level of the water level operation or the restrictive water level of the designed emptying facility. The anti-seepage and reinforcement treatment of the foundation above this elevation is carried out by lowering the operation water level, and the anti-seepage and reinforcement treatment of the foundation below this elevation is carried out under the water level;

[0022] Carry out the excavation of the dam foundation, the excavation of the foundation of the onshore toe slab and the basic grouting gallery structure, and the excavation of the foundation of the cross-river traffic galleries on both sides. Among them, the foundation of the basic grouting gallery structure is formed by groove excavation according to its shape, and the bottom anchorage groove is excavated and expanded corresponding to the structural joint Ⅰ of the basic grouting gallery structure;

[0023] Pour the basic grouting gallery structure, including the copper sheet water stop Ⅰ embedded in the basic grouting gallery structure. A sump is set at the lowest elevation of the bottom slab in the riverbed part, and the water stop copper sheet Ⅱ connected to the onshore toe slab is embedded at both ends of the basic grouting gallery structure;

[0024] Pour the concrete gallery structure of the cross-river traffic galleries on both sides;

[0025] Carry out the consolidated grouting and curtain grouting construction of the foundation of the basic grouting gallery structure in the order of first consolidated grouting and then curtain grouting;

[0026] Drill holes and install basic anchor bars within the scope of the onshore toe slab foundation;

[0027] Pour the onshore toe slab;

[0028] Carry out the consolidated grouting and curtain grouting construction of the onshore toe slab foundation in the order of first consolidated grouting and then curtain grouting;

[0029] Construct the part above the ground according to the construction technology requirements of the concrete face rockfill dam.

[0030] The beneficial effects of the present invention are as follows: In the present invention, the basic grouting gallery structure is adopted as a part of the bottom toe slab structure of the concrete face rockfill dam. The grouting gallery in the basic grouting gallery structure is connected to the outside of the downstream of the dam through the cross-river traffic galleries on both sides. The consolidated grouting and curtain grouting of the concrete face rockfill dam have the conditions for construction after impoundment, which further improves the operation flexibility of the concrete face rockfill dam, improves the operation efficiency of the reservoir, and reduces the operation and maintenance cost of the reservoir. Description of the Drawings

[0031] Figure 1 It is the schematic plan layout diagram of the embodiment.

[0032] Figure 2 It is the typical structural diagram of the dam body at the onshore toe slab part in the embodiment.

[0033] Figure 3 It is the typical structural diagram of the dam body at the basic grouting gallery structure part in the embodiment.

[0034] Figure 4 It is a cross-sectional schematic diagram of the water-stop structure I in the embodiment.

[0035] Figure 5 It is a schematic cross-sectional view of the water-stop structure II in the embodiment (vertical to the grouting gallery direction).

[0036] Figure 6 It is a cross-sectional schematic diagram of the water-stop structure II in the embodiment (in the direction perpendicular to the traffic corridor).

[0037] Figure 7 It is a typical structural diagram of the traffic corridor in the embodiment.

[0038] 1. Reservoir bank; 2. Riverbed; 3. Concrete panel rockfill dam; 4. Concrete panel; 5. Foundation grouting gallery structure; 6. Shore toe board; 7. Concrete gallery structure; 8. Wave-breaking wall; 9. Peripheral joint; 10. Top water stop; 11. Foundation anchor bar; 12. Consolidation grouting; 13. Curtain grouting; 14. Special cushion material; 16. Copper sheet water stop I; 17. Bottom anchor groove; 18. Surface bulge type water stop I; 19. Rock anchor groove; 20. Copper sheet water stop II; 21. Anchor groove under toe board; 22. Surface bulge type water stop II; 23. Foundation anchor groove; 24. Transition material area. DETAILED DESCRIPTION

[0039] The present embodiment is a concrete panel rockfill dam structure with a foundation grouting gallery. The concrete panel rockfill dam is built across the river and is located on the riverbed and the reservoir bank. The upstream of the concrete panel rockfill dam adopts concrete panels for anti-seepage. The toe plate structure at the bottom of the upstream surface of the concrete panel rockfill dam is divided into a foundation grouting gallery structure body arranged corresponding to the riverbed and the low-elevation areas on both sides, and an onshore toe plate arranged corresponding to the high-elevation areas on both sides, wherein the grouting gallery in the foundation grouting gallery structure body is connected to the outside of the downstream dam body of the concrete panel rockfill dam through traffic corridors on both sides.

[0040] In this case, horizontal joints and top waterstops are provided between the top of the concrete panel and the top wave-breaking wall of the concrete panel rockfill dam, and peripheral joints and waterstops are provided between the bottom of the concrete panel and the foundation grouting gallery structure and the onshore toe plate.

[0041] In this embodiment, the structural joint I of the foundation grouting gallery structure is provided with a water-stop structure I, which includes a copper sheet water-stop I embedded in the concrete and a surface bulge-type water-stop I formed by filling with plastic filler.

[0042] In this example, the copper sheet water stop Ⅰ is embedded in the foundation grouting gallery structure and is located on the upstream side of the grouting gallery. One end of the copper sheet water stop Ⅰ is connected to the bottom copper sheet water stop of the peripheral joint by a T-shaped joint, and the other end extends into the bottom anchorage groove under the foundation grouting gallery structure and is anchored by pouring expansion concrete; the surface bulge type water stop Ⅰ is arranged across the top structural joint Ⅰ of the foundation grouting gallery structure, one end is integrally connected to the surface bulge type water stop on the peripheral joint, and the other end extends into the rock anchorage groove on the upstream side rock mass of the foundation grouting gallery structure.

[0043] In this example, there is a structural joint Ⅱ between the foundation grouting gallery structure and the onshore toe slab, and a water stop structure Ⅱ is provided corresponding to the structural joint. The water stop structure Ⅱ includes a copper sheet water stop Ⅱ and a surface bulge type water stop Ⅱ.

[0044] In this example, the copper sheet water stop Ⅱ is arranged across the structural joint Ⅱ. The two sides of the copper sheet water stop Ⅱ are respectively connected to the foundation grouting gallery structure and the onshore toe slab. One end of the copper sheet water stop Ⅱ is connected to the bottom copper sheet water stop of the peripheral joint on the upstream surface of the concrete face rockfill dam by a T-shaped joint, and the other end is anchored in the toe slab lower anchorage groove under the onshore toe slab; the surface bulge type water stop Ⅱ is arranged across the top of the structural joint Ⅱ between the foundation grouting gallery and the onshore toe slab, one end is integrally connected to the surface bulge type water stop of the peripheral joint, and the other end extends into the foundation anchorage groove at the top of the foundation grouting gallery structure at the upstream end of the structural joint.

[0045] In this embodiment, foundation anchor bars, consolidated grouting and curtain grouting are provided in the toe slab foundation under the onshore toe slab; consolidated grouting and curtain grouting are provided in the foundation under the foundation grouting gallery structure.

[0046] In this example, the traffic gallery adopts a concrete gallery structure embedded in the concrete face rockfill dam body. The foundation of the concrete gallery structure is located on the excavated natural foundation, and there is a transition material area with a thickness of not less than 1m between the outside of the concrete gallery structure and the dam body. In this example, a special cushion material is provided on the downstream side of the peripheral joint in the concrete face rockfill dam body.

[0047] In this embodiment, drainage ditches are provided on both sides of the bottom plate of the grouting gallery in the foundation grouting gallery structure, and pedestrian steps are provided in the part of the grouting gallery corresponding to the bank slope.

[0048] The specific construction method of this embodiment is as follows:

[0049] Determine the layout elevation of the foundation grouting gallery structure according to the reservoir operation requirements, topographic and geological conditions combined with investment analysis; this elevation is generally the sensitive water level of water level operation or the limit water level of the existing emptying facilities. The foundation anti-seepage and reinforcement treatment above this elevation is carried out by lowering the operation water level, and the foundation anti-seepage and reinforcement treatment below this elevation can be carried out under the water level.

[0050] The foundation excavation of the concrete face rockfill dam is carried out according to the design requirements, including the excavation of the foundation of the onshore toe slab and the foundation grouting gallery structure body, and the excavation of the traffic gallery foundation. Among them, the foundation grouting gallery structure body is formed by grooving according to its shape, and an anchor groove is excavated and enlarged at the structural joint Ⅰ of the foundation grouting gallery structure body.

[0051] Pour the foundation grouting gallery structure bodies of the riverbed and both banks, including embedding copper sheet waterstops Ⅰ corresponding to the structural joint Ⅰ in the concrete of the gallery structure body; set a sump at the lowest elevation of the bottom slab in the riverbed part, and embed waterstop copper sheets Ⅱ connected to the onshore toe slab at both ends of the foundation grouting gallery structure body.

[0052] Pour the concrete gallery structure of the traffic galleries on both banks. First, pour the upstream part intersecting with the foundation grouting gallery structure body. The traffic galleries in the concrete face rockfill dam body can be arranged according to the construction sequence of the dam body.

[0053] Carry out the consolidation grouting and curtain grouting construction of the foundation of the foundation grouting gallery structure body in the order of first consolidation and then curtain.

[0054] Drill holes and install foundation anchor bars within the foundation range of the onshore toe slab.

[0055] Pour the onshore toe slab, including embedding copper sheet waterstops in the structural joints of the toe slab.

[0056] Carry out the consolidation grouting and curtain grouting construction of the onshore toe slab foundation in the order of first consolidation and then curtain.

[0057] Construct the part above the ground according to the construction technology requirements of the concrete face rockfill dam, including the special cushion material downstream of the peripheral joint, dam body filling, concrete face, wave wall, surface waterstop structure, downstream dam surface protection, etc.

Claims

1. A concrete face rockfill dam structure with a basic grouting gallery, characterized in that: The toe slab structure on the upstream face of the concrete face rockfill dam is divided into a foundation grouting gallery structure corresponding to the riverbed and the low-elevation areas on both banks and an onshore toe slab corresponding to the high-elevation areas on both banks; The grouting galleries in the foundation grouting gallery structure are connected to the outside of the downstream dam body of the concrete face rockfill dam through traffic galleries on both banks; A waterstop structure I is provided at the structural joint I of the foundation grouting gallery structure; there is a structural joint II between the foundation grouting gallery structure and the onshore toe slab, and a waterstop structure II is provided corresponding to the structural joint II; The waterstop structure I includes a copper sheet waterstop I and a surface bulge type waterstop I; Among them, the copper sheet waterstop I is located in the foundation grouting gallery structure and on the upstream side of the grouting gallery. One end of the copper sheet waterstop I is connected to the bottom copper sheet waterstop of the upper peripheral joint on the upstream face of the concrete face rockfill dam, and the other end extends into the bottom anchorage groove under the foundation grouting gallery structure and is anchored; The surface bulge type waterstop I is arranged across the top structural joint I of the foundation grouting gallery structure, with one end connected to the surface bulge type waterstop on the peripheral joint to form a whole, and the other end extending into the rock anchorage groove on the upstream side rock mass of the foundation grouting gallery structure; The waterstop structure II includes a copper sheet waterstop II and a surface bulge type waterstop II; Among them, the copper sheet waterstop II is arranged across the structural joint II, with both sides of the copper sheet waterstop II connected to the foundation grouting gallery structure and the onshore toe slab respectively. One end of the copper sheet waterstop II is connected to the bottom copper sheet waterstop of the upper peripheral joint on the upstream face of the concrete face rockfill dam, and the other end is anchored in the toe slab lower anchorage groove under the onshore toe slab; The surface bulge type waterstop II is arranged across the top of the structural joint II between the foundation grouting gallery and the onshore toe slab, with one end connected to the surface bulge type waterstop of the peripheral joint to form a whole, and the other end extending into the foundation anchorage groove at the top of the upstream end of the structural joint II and the foundation grouting gallery structure; 2. The concrete face rockfill dam structure with a foundation grouting gallery according to claim 1, characterized in that: The toe slab foundation under the onshore toe slab is provided with foundation anchor bars, consolidated grouting, and curtain grouting.

3. The concrete face rockfill dam structure with a foundation grouting gallery according to claim 1, characterized in that: The foundation under the foundation grouting gallery structure is provided with consolidated grouting and curtain grouting.

4. The concrete face rockfill dam structure with a foundation grouting gallery according to claim 1, characterized in that: A special cushion material is provided in the concrete face rockfill dam body on the downstream side of the peripheral joint.

5. The concrete face rockfill dam structure with a foundation grouting gallery according to claim 1, characterized in that: Drainage ditches are provided on both sides of the bottom plate of the grouting gallery in the foundation grouting gallery structure, and pedestrian steps are provided in the part of the grouting gallery corresponding to the bank slope.

6. The concrete face rockfill dam structure with a foundation grouting gallery according to claim 1, characterized in that: The traffic gallery adopts a concrete gallery structure embedded in the concrete face rockfill dam body. The foundation of the concrete gallery structure is located on the excavated natural foundation, and there is a transition material area with a thickness of not less than 1m between the outside of the concrete gallery structure and the dam body.

7. A construction method for the concrete face rockfill dam structure with a foundation grouting gallery according to any one of claims 1 to 6, characterized in that: Determine the elevation of the layout of the foundation grouting gallery structure, which is the sensitive water level of water level operation or the restrictive water level of the designed emptying facility. The foundation anti-seepage reinforcement treatment above this elevation is carried out by lowering the operation water level, and the foundation anti-seepage reinforcement treatment below this elevation is carried out under the water level; Carry out foundation excavation of the dam, foundation excavation of the onshore toe slab and the foundation grouting gallery structure body, and foundation excavation of the cross-river traffic galleries on both banks. Among them, the foundation of the foundation grouting gallery structure body is formed by grooving according to its shape, and the bottom anchor groove is excavated wider at the position of structural joint Ⅰ of the corresponding foundation grouting gallery structure body; Pour the foundation grouting gallery structure body, including copper sheet waterstop Ⅰ embedded in the foundation grouting gallery structure body. A sump is set at the lowest elevation of the bottom slab in the riverbed area, and waterstop copper sheet Ⅱ connected to the onshore toe slab is embedded at both ends on both sides of the foundation grouting gallery structure body; Pour the concrete gallery structure of the cross-river traffic galleries on both banks; Carry out consolidation grouting and curtain grouting construction of the foundation of the foundation grouting gallery structure body in the order of first consolidation and then curtain; Drill holes within the scope of the onshore toe slab foundation to install foundation anchor bars; Pour the onshore toe slab; Carry out consolidation grouting and curtain grouting construction of the onshore toe slab foundation in the order of first consolidation and then curtain; Construct the part above the ground according to the construction process requirements of the concrete face rockfill dam.

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