Clay core dam with anti-seepage self-healing function and implementation method thereof

Abstract

The present application relates to a kind of clay core dam with anti-seepage self-healing function and its implementation method.The purpose of the present application is to provide a kind of clay core dam with anti-seepage self-healing function and its implementation method, to make dam in high seismic force caused by large deformation conditions guarantee the permeation and the permeation stability in controllable and safe state.The technical scheme of the present application is: a kind of clay core dam with anti-seepage self-healing function, with clay core in the inside, characterized in that: the upstream side of the clay core is provided with self-healing silt area;When tensile or dislocation crack appears in clay core, the silt in self-healing silt area can flow to fill the crack of clay core.The present application is applicable to the earth-rock dam engineering built in high seismic intensity area.

Description

TECHNICAL FIELD

[0001] The present application relates to a clay core dam with anti-seepage self-healing function and its implementation method, which is suitable for earth-rock dam engineering built in high seismic intensity area. BACKGROUND

[0002] An important reason restricting the construction of reservoirs in high seismic intensity area is the problem of seismic safety of dam. The problem of seismic safety of dam mainly includes the problems of dam structure stability and seepage stability. There are many ways to deal with the problem of dam structure stability, and the technology is also relatively mature. However, the problem of seepage safety under the condition of large deformation caused by high seismic force is difficult to deal with, and once seepage failure occurs, it is likely to cause dam break, which is serious. This is also an important reason restricting the construction of earth-rock dam in high seismic intensity area. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a clay core dam with anti-seepage self-healing function and its implementation method to ensure that the seepage amount and seepage stability of the dam are in a controllable and safe state under the condition of large deformation caused by high seismic force.

[0004] The technical solution adopted by the present application is: a clay core dam with anti-seepage self-healing function, which has a clay core inside, characterized in that: a self-healing silt area is arranged on the upstream side of the clay core.

[0005] When tensile or dislocation cracks appear in the clay core, the silt in the self-healing silt area can flow to fill the cracks in the clay core.

[0006] The cohesion of the silt in the self-healing silt area is much lower than that of the clay core material, and the compaction standard of the self-healing silt area is not lower than that of the clay core.

[0007] An upstream filter zone I, an upstream filter zone II, an upstream transition zone and an upstream rockfill zone are sequentially arranged on the upstream side of the self-healing silt area.

[0008] A downstream filter zone I, a downstream filter zone II, a downstream transition zone and a downstream rockfill zone are sequentially arranged on the downstream side of the clay core.

[0009] The minimum width of the upstream transition zone, the upstream filter zone II, the upstream filter zone I, the clay core, the downstream filter zone I, the downstream filter zone II and the downstream transition zone is the corresponding design width of each zone of the clay core dam under non-seismic conditions + B, B is the maximum possible dislocation width of the clay core dam under seismic conditions; the minimum width of the top of the self-healing silt area is B and greater than or equal to 2m, and the bottom width of the self-healing silt area is appropriately widened.

[0010] The maximum width of the self-healing silt area is less than 0.5 times h / I crControl, wherein h is the design water head corresponding to the bottom of the clay core, I cr is the critical hydraulic gradient of silt.

[0011] The clay core is located on a core foundation structure, the core foundation structure has a concrete bottom plate, and a consolidated grouted rock foundation is below the concrete bottom plate. A certain thickness of contact clay is provided between the bottom of the clay core and the concrete bottom plate. A gallery is provided in the concrete bottom plate, and a grouting curtain is provided downward through the gallery.

[0012] The clay core dam has a reinforced area at the top of the dam, and a plurality of reinforced belts are laid at different elevations and intervals in the reinforced area. The reinforced belt has steel bars and a plurality of concrete anchoring blocks poured on the steel bars.

[0013] The clay core dam is provided with a reinforced concrete grid beam on the upstream and downstream dam surfaces, and the reinforced belt is node-anchored with the reinforced concrete grid beam.

[0014] A construction method of the clay core dam, characterized in that:

[0015] According to the results of seismic analysis, the maximum displacement width B of the dam body that may exist is predicted;

[0016] The dam body is initially determined, the seismic stability analysis is carried out, the upstream and downstream dam slopes are determined, the partition design is carried out, and the reinforcement measures are reviewed;

[0017] The dam foundation is excavated, the concrete bottom plate and the gallery are constructed;

[0018] The rock foundation below the reinforced concrete bottom plate is consolidated and grouted under the cover of the reinforced concrete bottom plate;

[0019] The dam body is filled and rolled layer by layer;

[0020] After filling to the reinforced area at the top of the dam, the reinforced belts are laid at different elevations and intervals according to the design;

[0021] The upstream and downstream dam slopes are trimmed every 10-20m of filling;

[0022] After filling to the top of the dam, the wave protection wall at the top of the dam is constructed, and the transition material and road concrete at the top of the dam are filled;

[0023] The reinforced concrete grid beams on the upstream and downstream slopes and the filling of the beams with grass are constructed;

[0024] After the dam is filled, curtain grouting is carried out through the gallery in a timely manner.

[0025] The laying of the reinforced belts includes:

[0026] Excavate a pit with a depth of half the height of the anchoring block on the reinforced belt laying surface, lay the steel bar, and then cast early strength concrete to form a concrete anchoring block anchored to the steel bar, and lay a transition layer on the surface of the anchoring block.

[0027] The application has the advantages that: the application fills the silt area on the clay core wall, utilizes the characteristics of low cohesion, low resistance to penetration damage and medium-low permeability of silt, assists in anti-seepage in normal operation, protects the clay core wall, fills the cracks of the clay core wall when the cracks appear, reduces the trend of continuous expansion of the cracks under the action of hydraulic fracturing and scouring, and gradually reaches a seepage stable state, avoids seepage damage of the dam or delays the time of seepage damage, and provides time for dam repair and personnel evacuation. The application reduces or even eliminates the risk of silt liquefaction under the action of an earthquake or the risk of overall stability of the dam body caused by silt liquefaction through comprehensive measures such as control of the filling elevation, compaction standard and clay content of silt.

[0028] The application widens the clay core wall, the width of the filter material and the transition material, so that the dam still has a sufficient width of structural lap under the maximum predicted displacement, and the overall failure of the structure is avoided.

[0029] The application utilizes the superior tensile properties of the steel bar and the strong bite of the concrete anchoring block and the rockfill body to form a reinforced belt with superior performance, and the reinforced belt cooperates with the grid beam on the surface of the clay core wall dam to improve the anti-seismic performance of the dam top.

[0030] The application can plant grass in the middle area of the grid beam to improve the harmony of the dam and the surrounding natural environment. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 A typical cross-sectional view of the embodiment.

[0032] Figure 2 A schematic view of the laying of the reinforced belt in the embodiment.

[0033] Figure 3 A typical structure diagram of the anchoring block of the reinforced belt in the embodiment. DETAILED DESCRIPTION

[0034] The embodiment is a clay core wall dam with anti-seepage self-healing function, the dam body of the clay core wall dam has a clay core wall 12, the upstream side of the clay core wall 12 is sequentially provided with a self-healing silt area 11, an upstream filter area I 10, an upstream filter area II 9, an upstream transition area 8 and an upstream rockfill area 7, and the downstream side of the clay core wall 12 is sequentially provided with a downstream filter area I 13, a downstream filter area II 14, a downstream transition area 15 and a downstream rockfill area 16.

[0035] The dam foundation of the clay core dam in this embodiment is divided into a core wall foundation in the middle region and a rock foundation or a dense soil foundation without seismic liquefaction risk on the upstream and downstream of the core wall foundation; the core wall foundation structure has a concrete bottom plate 5, the rock foundation below the concrete bottom plate 5 is consolidated by grouting 2, and a certain thickness of contact clay 6 is arranged between the bottom of the clay core wall 12 and the concrete bottom plate 5; a corridor 4 is arranged in the concrete bottom plate 5, and a grouting curtain 3 is arranged downwardly through the corridor 4 to perform seepage control treatment on the rock mass 1 at the lower part of the corridor 4. In this embodiment, the clay core wall 12 is arranged on the concrete bottom plate 5, and a certain thickness of contact clay 6 is arranged at the bottom of the clay core wall 12.

[0036] In this embodiment, the self-healing silt area 11 is filled from the bottom of the self-healing silt area 11 to a position at a certain height from the dam top to ensure that the upstream and top of the self-healing silt area 11 have a certain thickness of covering. The filling height of the self-healing silt area 11 is determined by taking the normal water storage level or the frequently encountered water level as the upper limit and comprehensively considering the covering thickness determined by the seismic liquefaction discrimination. The soil used in the self-healing silt area 11 generally has a clay content of not less than 5%, and the mechanical indexes of saturated consolidation quick shear have the characteristics of low cohesion (not higher than the cohesion of the clay core wall soil in the downstream, and maintaining a large gap) and high internal friction angle. The rolling and compaction standard of the self-healing silt area 11 is not lower than the compaction standard of the core wall.

[0037] In this embodiment, the design thicknesses of the filling partitions of the clay core dam are determined according to the design parameters under non-seismic conditions and the results of seismic analysis. First, the maximum possible displacement width of the dam under seismic working conditions is predicted, which is assumed to be B. The minimum width of the upstream transition zone 8, the upstream filter zone II 9, the upstream filter zone I 10, the clay core wall 12 zone, the downstream filter zone I 13, the downstream filter zone II 14, and the downstream transition zone 15 is the corresponding design width of the clay core dam under non-seismic conditions + B.

[0038] In this embodiment, the size of the self-healing silt area 11 is controlled according to the maximum / minimum principle: the minimum width at the top is B, and the width at the top is not less than 2m; the bottom width is appropriately widened, and the maximum width is controlled to be less than 0.5 times h / I cr , h is the corresponding design water head at the bottom of the core wall, and I cr is the critical hydraulic slope of silt. The minimum thickness principle ensures that the silt upstream has enough quantity to fill the cracks that may be generated in the clay core wall 12, and the maximum thickness principle controls the thickness of the silt as much as possible. In the initial stage of the cracks in the clay core wall 12, the silt can be smoothly driven by the water flow under the action of seepage pressure to enter the cracks in the clay core wall 12, fill and repair the cracks.

[0039] The dam top part of 1 / 3 dam height range in this example is a reinforced zone, and a plurality of reinforced belts 17 are laid in the reinforced zone at different elevations, and the reinforced belts 17 are used for reinforcement treatment. The reinforced belt 17 in this example has a steel bar 17-1 and a plurality of concrete anchoring blocks 17-2 poured on the steel bar, and the surface of the steel bar 17-1 is brushed with asphalt to form a corrosion-proof layer; the anchoring blocks are approximately cubic structures with an edge length of about 40-50 cm.

[0040] In this embodiment, a reinforced concrete grid beam 18 is arranged on the upstream and downstream dam surfaces of the clay core dam, and the grid beam is laid with planting soil for grass planting and greening. The reinforced belts 17 in the clay core dam are anchored with the reinforced concrete grid beam 18 to improve the anti-seismic performance of the dam top.

[0041] The specific implementation steps of this embodiment are as follows:

[0042] According to the seismic analysis results, the maximum possible displacement width B of the dam body is predicted;

[0043] The dam body type is initially determined, the anti-seismic stability analysis is performed, the upstream and downstream dam slopes are determined, the partition design is performed, and the reinforcement measures are reviewed;

[0044] The dam foundation is excavated, and the concrete bottom plate 5 and the gallery 4 are poured;

[0045] The consolidation grouting 2 is constructed under the action of the reinforced concrete bottom plate cover;

[0046] The dam body is filled and compacted layer by layer;

[0047] After filling to the reinforced zone of the dam top, the reinforced belts 17 formed by the steel bars 17-1 and the concrete anchoring blocks 17-2 are laid at the designed elevational intervals; pits with a depth of half the height of the anchoring blocks are excavated on the reinforced belt laying surface 21, the steel bars 17-1 are laid, and the early strength concrete is poured to form the concrete anchoring blocks 17-2 connected to the steel bars 17-1, and a transition layer 22 with a thickness of about 50 cm is filled on the upper part and the periphery of the anchoring blocks for protection;

[0048] The upstream and downstream dam slope surfaces are trimmed every 10-20 m of filling;

[0049] After filling to the dam top, the dam top wave protection wall 19 is constructed, and the transition material and the pavement concrete 20 are filled on the dam top;

[0050] The reinforced concrete grid beams on the upstream and downstream slope surfaces and the soil filling and grass planting in the beams are constructed;

[0051] In the later stage of dam filling, the curtain grouting 3 is constructed through the gallery 4 in time.

[0052] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A clay core dam with anti-seepage self-healing function, having a clay core in the inside, characterized in that: The upstream side of the clay core wall is provided with a self-healing silt area; When tensile or dislocation cracks appear in the clay core wall, the silt in the self-healing silt area can flow to fill the cracks in the clay core wall; The self-healing silt area adopts silt with a cohesion much lower than that of the clay core wall, and the compaction standard of the self-healing silt area is not lower than that of the clay core wall; The upstream side of the self-healing silt area is sequentially provided with an upstream filter zone I, an upstream filter zone II, an upstream transition zone and an upstream rockfill zone; The downstream side of the clay core wall is sequentially provided with a downstream filter zone I, a downstream filter zone II, a downstream transition zone and a downstream rockfill zone; The minimum width of the upstream transition zone, the upstream filter zone II, the upstream filter zone I, the clay core wall, the downstream filter zone I, the downstream filter zone II and the downstream transition zone is the corresponding design width of each zone of the clay core wall dam under non-seismic conditions + B, B is the maximum possible dislocation width of the clay core wall dam under seismic conditions; the minimum width of the top of the self-healing silt area is B and greater than or equal to 2m, and the bottom width of the self-healing silt area is appropriately widened; The maximum width of the self-healing silt region is less than 0.5 times h / I cr Control, wherein h is the design water head corresponding to the bottom of the clay core, I cr is the critical hydraulic slope of the silt.

2. The clay core dam with anti-seepage self-healing function according to claim 1, characterized in that: The clay core wall is located on a core wall foundation structure, the core wall foundation structure has a concrete bottom plate, the bottom of the concrete bottom plate is a rock foundation subjected to consolidation grouting, and a certain thickness of contact clay is provided between the bottom of the clay core wall and the concrete bottom plate; a gallery is provided in the concrete bottom plate, and a grouting curtain is provided downward through the gallery.

3. The clay core dam with anti-seepage self-healing function according to claim 1, characterized in that: The top part of the clay core wall dam is a reinforced zone, and a plurality of reinforced belts are laid in different elevations in the reinforced zone; 4. The clay core dam with anti-seepage self-healing function according to claim 3, characterized in that: Steel reinforced concrete grid beams are provided on the upstream and downstream dam surfaces of the clay core wall dam, and the reinforced belts are node anchored with the steel reinforced concrete grid beams.

5. A construction method of the clay core wall dam according to any one of claims 1-4, characterized in that: According to the seismic analysis results, the maximum dislocation width B of the dam body is predicted; The dam body type is initially determined, seismic stability analysis is performed, the upstream and downstream dam slopes are determined, and the reinforcement measures are reviewed; The dam foundation is excavated, the concrete bottom plate and the gallery are constructed; The rock foundation below the steel reinforced concrete bottom plate is subjected to consolidation grouting under the cover of the bottom plate; The dam body is filled layer by layer; After the reinforced zone at the top of the dam is filled, the reinforced belts are laid in different elevations according to the design; The upstream and downstream dam slopes are trimmed every 10-20m of filling; After the dam is filled to the top, the wave protection wall at the top of the dam is constructed, the transition material at the top of the dam is filled, and the road surface concrete is constructed; The steel reinforced concrete grid beams on the upstream and downstream slopes and the filling and grass planting in the beams are constructed; The curtain grouting is performed through the gallery in the later stage of dam filling.

6. The construction method according to claim 5, characterized in that, The laying of the reinforced belts includes: A pit with a depth of half the height of the anchoring block is excavated on the laying surface of the reinforced belt, the anchoring block is formed by pouring early strength concrete after laying the steel bars, and a transition layer is laid on the surface of the anchoring block.

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