Asphalt concrete core wall structure of ultrahigh rock-fill dam and construction method of asphalt concrete core wall structure

Abstract

The invention belongs to an asphalt concrete core wall structure of an ultrahigh rock-fill dam and a construction method of the asphalt concrete core wall structure. An asphalt concrete core wall is formed by stacking a plurality of prefabricated asphalt concrete bricks and an adhesive capable of bonding the prefabricated asphalt concrete bricks into a whole. Each prefabricated asphalt concrete brick is mechanically pressed in a prefabrication factory according to the set weight, mass, size and density, and the ratio of the length to the width to the height of each prefabricated asphalt concrete brick is 4: 2: 1; the two side faces of the asphalt concrete core wall are sequentially and correspondingly provided with a concrete grouting stone-building wall, a first transition layer and a second transition layer. The prefabricated asphalt concrete brick is mechanically pressed in an asphalt concrete brick prefabrication factory according to the set unified weight, size, density and quality, so that an asphalt concrete core wall is not influenced by weather during piling construction, and the construction quality of the asphalt concrete core wall can be ensured.

Description

Technical Field

[0001] The invention belongs to an asphalt concrete core wall structure of a super-high rockfill dam and a construction method thereof. Background Art

[0002] An asphalt concrete core wall dam refers to an earth-rock dam with an asphalt concrete core wall as an anti-seepage body in the middle of the dam body. Transition layers are provided on both sides of the asphalt concrete core wall, and a stone layer is provided outside the transition layer. The transition layer is used to improve the bonding strength between the asphalt concrete core wall and the stone layer, and the stone layer is used to enhance the overall stability and anti-scouring ability of the dam body. A concrete pad is provided at the bottom of the asphalt concrete core wall to connect with the base bank or slope. If the concrete pad is located on a very thick alluvial layer, an anti-seepage curtain or a concrete anti-seepage wall-type anti-plate column may be provided at its lower end.

[0003] There are two construction methods for asphalt concrete core wall: on-site rolling and on-site casting. Rolled asphalt concrete construction includes raw material preparation, heating, weighing and mixing of asphalt mixture, transportation, on-site paving and rolling, and repeated layer-by-layer raising to form the asphalt concrete core wall; cast asphalt concrete construction includes preparation, measurement, formwork placement, asphalt concrete heating, paving and rolling with professional equipment, and formwork removal, and repeated layer-by-layer raising to form the asphalt concrete core wall. The traditional construction method of asphalt concrete core wall requires that construction can only be carried out when the minimum temperature is greater than 0℃, the wind speed is less than level 4, and the daily precipitation is less than 5mm. When the minimum temperature is below -10℃, construction must be stopped. In the process of laying asphalt concrete, the surface temperature of the lower asphalt concrete layer laid first must be above 70℃ before the upper asphalt concrete layer can be laid on it. The thickness of a single-layer asphalt concrete layer cannot be greater than 25cm. After laying the asphalt concrete, a small vibrating roller of less than 1.5t is used for rolling to ensure that the laid asphalt concrete is compacted. In the construction of asphalt concrete core wall dam, alkaline aggregate must be used, and the oil-stone ratio is between 6% and 8%.

[0004] According to the above-mentioned specifications, it is difficult to ensure the quality of asphalt concrete core walls in high-altitude areas above 3,000 meters above sea level, where the daily minimum temperature is often less than 0°C and the wind speed is greater than Level 4.

[0005] Therefore, it is necessary to find a construction method to replace the existing on-site rolling and on-site pouring types of asphalt concrete core walls. Summary of the invention

[0006] The object of the present invention is to provide an asphalt concrete core wall structure of a super-high rockfill dam and a construction method thereof, so as to solve the problems raised in the above-mentioned background technology.

[0007] An asphalt concrete core wall structure of an ultra-high rockfill dam, which is composed of a rockfill area, a concrete base and a slope gravel layer. The asphalt concrete core wall is formed by stacking a number of prefabricated asphalt concrete bricks and an adhesive that can bond the prefabricated asphalt concrete bricks together. The prefabricated asphalt concrete bricks are mechanically pressed in a prefabrication plant according to a set weight, mass, size and density. The length, width and height ratio of each prefabricated asphalt concrete brick is 4:2:1. The two sides of the asphalt concrete core wall are provided with a concrete grouting stone wall, a first transition layer and a second transition layer in sequence; or the two sides of the asphalt concrete core wall are provided with a first transition layer and a second transition layer in sequence; Grouting sealing material is provided between the asphalt concrete core wall and the concrete grouted stone wall.

[0008] As a further description of the above technical solution: the prefabricated asphalt concrete bricks are stacked and arranged in an interlaced manner to form an asphalt concrete core wall.

[0009] As a further description of the above technical solution: the prefabricated asphalt concrete brick is a rectangular body, and the length, width and height of the prefabricated asphalt concrete brick are preferably 0.8m, 0.4m, 0.2m, or 1.6m, 0.8m in width and 0.4m in height.

[0010] As a further description of the above technical solution: the mass-to-weight ratio of the prefabricated asphalt concrete brick material is: 10% coarse aggregate with a particle size of 10-15mm, 22% coarse aggregate with a particle size of 5-10mm, 23% coarse aggregate with a particle size of 2.5-5mm, 30% fine aggregate with a particle size of 0.074-2.5mm, 7% sand with a particle size less than 0.074mm, 1-2% mineral powder, and 6-7% oilstone.

[0011] As a further description of the above technical solution: the adhesive is any one of emulsified asphalt, modified emulsified asphalt, sandy asphalt mastic, resin modified asphalt adhesive, and asphalt mortar.

[0012] As a further description of the above technical solution: the grouting sealing material is any one of cement mortar, emulsified asphalt, modified emulsified asphalt, and sandy asphalt mastic.

[0013] A construction method for an asphalt concrete core wall structure of a super-high rockfill dam comprises the following steps: (1) Build an asphalt concrete brick prefabrication plant in a flat area near the super-high rockfill dam construction site. The production plant equipment includes batching and drying equipment, heating equipment, weighing and batching equipment, heating and mixing equipment, material dividing and metering warehouse, brick pressing equipment, and brick storage warehouse; (2) The cold aggregates constituting the asphalt concrete bricks are first placed in a drying and drying device for drying, then placed in a weighing and batching device for screening and metering, and then placed in a heating and mixing device together with mineral powder and asphalt for heating and mixing to form asphalt concrete materials. The asphalt concrete materials are heated and mixed together with mineral powder and asphalt to form asphalt concrete materials. The asphalt concrete materials are discharged from the warehouse at a temperature less than 120°C. The asphalt concrete materials are passed through various material dividing and metering bins to form the material quantity required for one asphalt concrete brick. The material dividing and metering bins place the material quantity required for one asphalt concrete brick into the brick material trough of the brick mold in the brick pressing device. The brick pressing device presses the asphalt concrete bricks into asphalt concrete bricks of uniform weight, size, density and quality. The pressed asphalt concrete bricks are placed in a brick storage warehouse for storage and standby use. (3) The pressed asphalt concrete bricks are transported to the rockfill dam construction site, and the lines are marked and staked out before construction to ensure that the wall is aligned with the construction site. Figure 1 The asphalt concrete core wall is built by stacking prefabricated asphalt concrete bricks and adhesives. The adhesives are located between the intersecting surfaces of adjacent prefabricated asphalt concrete bricks. The prefabricated asphalt concrete bricks are arranged in a staggered manner. The integrity of the wall is ensured by horizontal wall reinforcements. The flatness and verticality of the wall are checked with professional tools. (4) Each asphalt concrete brick core wall is 50m to 70m long and 0.60 to 0.8m high, which is a construction section. After the asphalt concrete brick core wall of the construction section is completed, polygonal stones with a diameter greater than 20cm are immediately used to build a 35-40cm wide stone wall on both sides of the asphalt concrete brick core wall, close to the core wall surface, and the first transition layer is laid close to the outer side of the stone wall. The first transition layer is compacted, and cement mortar is filled in the brick joints of the stone wall. Grouting sealing materials are provided between the asphalt concrete core wall and the concrete grouting stone wall. The construction length and height of this section of the stone wall and the first transition layer are the same as the length and height of the asphalt concrete brick core wall of the construction section; Or: Each asphalt concrete brick core wall of 50m to 70m and 0.60 to 0.8m in height is a construction section. After the asphalt concrete brick core wall of the construction section is completed, the first transition layer is immediately laid on the outer end surfaces on both sides of the transverse side of the asphalt concrete brick core wall of the section, and the first transition layer is compacted. The construction length and height of the first transition layer of the section are the same as the length and height of the asphalt concrete brick core wall of the construction section; (5) According to the length and height of the stone wall and the first transition layer, the second transition layer, the rockfill area, the slope gravel cushion layer and the dry stone slope protection or lattice grass slope protection are constructed outwards in sequence; Or: construct the second transition layer, rockfill area, slope gravel cushion layer and dry stone slope protection or lattice grass slope protection in sequence outward according to the construction length and height of the first transition layer; (6) Repeat steps (3) to (5) to carry out the construction of the next construction section. The construction sections can be constructed adjacent to each other or in sections. The rockfill dam construction site can be divided into several construction sections. The height difference between the construction sections is less than 1 m until the super-high asphalt concrete core wall rockfill dam is completed.

[0014] As a further description of the above technical solution: the brick pressing equipment is that the four corners of the upper end of the base are respectively fixed to the lower ends of four guide columns, and the upper ends of the four guide columns are fixed to the four corners of the lower end of the top seat, and the upper end surface of the base on the inner side of each guide column is provided with a brick mold, and the four corners of the lower end of the brick mold are fixed to the upper end surface of the base by supporting legs, and a concave brick trough is provided in the middle of the upper end surface of the brick mold, and a top brick steel plate is provided on the bottom surface of the brick trough. The center of the lower end surface of the top brick steel plate is connected with the telescopic rod of the top brick hydraulic cylinder passing through the center of the lower end of the brick trough, and the top brick hydraulic cylinder is fixed to the base at the center of the lower end of the brick trough, and the four corners of the pressing plate are arranged on the four guide columns at the upper end of the brick mold through the shaft sleeve, and the brick pressing hydraulic cylinder is arranged on the middle of the upper end surface of the top seat plate, and the telescopic rod of the brick pressing hydraulic cylinder passes downward through the top seat and is connected with the middle of the upper end surface of the pressing plate, and a pressing die head is provided at the lower end of the pressing plate, and the shape and size of the pressing die head are adapted to the shape and size of the brick trough.

[0015] As a further description of the above technical solution: the height of the core wall expansion section at the lower part of the asphalt concrete core wall is 3.5m, and the width in the downstream direction narrows from 3m to 1.5m. The cross-sectional width of the core wall at the upper part of the core wall expansion section is 1.5m, and the cross-sectional width of the upper part of the core wall within 10m from the lower end of the dam top is 0.9m.

[0016] As a further description of the above technical solution: the width of the first transition layer on each side is 1.5m, the maximum particle size of the material in the first transition layer zone does not exceed 80mm, and the continuous grading weight ratio is 20-23% for particle size 60-80mm, 15-20% for particle size 40-60mm, 20-25% for particle size 20-40mm, 20-25% for particle size 5-20mm, 20-23% for particle size 0.25-5mm, and 4-5% for particle size 0.075-0.25mm.

[0017] The present invention has the following beneficial effects: 1. Since the asphalt concrete core wall of the present invention is formed by stacking a plurality of prefabricated asphalt concrete bricks and an adhesive that can bond the prefabricated asphalt concrete bricks together, and the prefabricated asphalt concrete bricks are mechanically pressed in an asphalt concrete brick prefabrication plant according to a set uniform weight, size, density, and quality, the asphalt concrete core wall construction is not affected by the climate and the construction quality of the asphalt concrete core wall is also guaranteed. During the construction of the asphalt concrete core wall of the present invention, as long as the construction conditions of the adhesive can be met, the stacking of the asphalt concrete core wall will not be affected by the climate. During the construction of the present invention, no on-site paving and rolling are required, and it is not restricted by the traditional on-site rolling and on-site pouring construction conditions, that is, there is no traditional "in the process of laying asphalt concrete, the surface temperature of the lower asphalt concrete layer laid first must be above 70°C before the upper asphalt concrete layer can be laid on it, and the thickness of the single-layer asphalt concrete layer cannot be greater than 25 cm; after laying the asphalt concrete, a small vibrating roller of less than 1.5t is used for rolling to ensure that the laid asphalt concrete is compacted" construction condition restriction, thereby enabling the present invention to have a faster construction speed and good construction quality during construction.

[0018] 2. The construction quality of the present invention is better than that of the traditional on-site rolling and on-site casting asphalt concrete core walls. Since the asphalt concrete bricks constituting the asphalt concrete core wall are prefabricated in the factory and mechanically pressed according to the set uniform weight, size, density and quality, the density and quality of the asphalt concrete core wall can be guaranteed to be uniform, so that the construction quality of the asphalt concrete core wall can meet the design requirements. The present invention will not produce the disadvantage that the upper layer of asphalt concrete will disturb the lower layer of asphalt concrete during layer-by-layer paving and rolling, causing cracks or gaps in the lower layer of asphalt concrete. The test comparison test shows that the construction quality of the present invention is better than that of the traditional on-site rolling and on-site casting asphalt concrete core walls.

[0019] 3. The present invention has low use cost. In order to ensure the minimum paving and rolling temperature of asphalt concrete in traditional on-site rolling and on-site casting asphalt concrete core walls, heating temperature of 140℃~160℃, transportation temperature of 120℃~150℃, paving temperature of 120℃~140℃, and rolling temperature of 110℃~140℃ are usually required. However, the present invention does not have the transportation, paving and rolling temperature requirements. The present invention makes the asphalt concrete fully stirred at less than 120℃, and the brick pressing temperature is lower than 120℃, so that the present invention can save a lot of energy costs, paving and rolling costs. Preliminary calculation shows that the use cost of the present invention is about 6% lower than that of the traditional method, and has better economic benefits.

[0020] 4. The present invention has a wide range of applications and can be applied to construction in areas with complex climates in various regions of my country. The present invention is convenient to construct, does not require large-scale construction machinery, has simple procedures, and is easy to master. The present invention has a good use effect and has the advantages of saving labor and effort during construction, simple construction, fast speed, material saving, high efficiency, and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the cross-sectional structure of the asphalt concrete core wall dam body of the present invention; Figure 2 It is a schematic diagram of the local structure of the lower end and both sides of the asphalt concrete core wall of the present invention; Figure 3 It is a schematic diagram of the local structure of the lower end of the asphalt concrete core wall of the present invention; Figure 4 It is a schematic diagram of the structure of the prefabricated asphalt concrete brick of the present invention; Figure 5 It is a schematic diagram of the local structure of the asphalt concrete core wall built with prefabricated asphalt concrete bricks in the present invention; Figure 6 It is a schematic diagram of the structure of the brick pressing device of the present invention; Figure 7 It is a schematic diagram of the local structure of the lower end and both sides of another asphalt concrete core wall of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described in conjunction with specific embodiments below, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work all belong to the protection scope of the present invention. The construction methods in the following embodiments, unless otherwise specified, are all conventional methods. The materials, devices, equipment, etc. used in the following embodiments, unless otherwise specified, can all be obtained from commercial channels.

[0023] Example 1: Figures 1 to 6 As shown, an asphalt concrete core wall structure of a super-high rockfill dam is composed of a rockfill area 11, a concrete base 14 and a slope gravel layer 4. The asphalt concrete core wall 8 is formed by stacking a plurality of prefabricated asphalt concrete bricks 3 and an adhesive that can bond the prefabricated asphalt concrete bricks together. Each prefabricated asphalt concrete brick 3 is mechanically pressed in a prefabrication plant according to a set weight, mass, size and density. The length, width and height ratio of each prefabricated asphalt concrete brick is 4:2:1; The two side surfaces of the asphalt concrete core wall are provided with a concrete grouted stone wall 10, a first transition layer 7 and a second transition layer 5 in sequence.

[0024] Grouting sealing material is provided between the asphalt concrete core wall and the concrete grouted stone wall.

[0025] Prefabricated asphalt concrete bricks are stacked in an alternating pattern to form an asphalt concrete core wall.

[0026] The prefabricated asphalt concrete brick 3 is a rectangular body, and the length, width and height of the prefabricated asphalt concrete brick are preferably 0.8m, 0.4m, 0.2m, or 1.6m, 0.8m in width and 0.4m in height.

[0027] The weight ratio of materials for prefabricated asphalt concrete brick 3 is: 10% of coarse aggregate with a particle size of 10-15mm, 22% of coarse aggregate with a particle size of 5-10mm, 23% of coarse aggregate with a particle size of 2.5-5mm, 30% of fine aggregate with a particle size of 0.074-2.5mm, 7% of sand with a particle size less than 0.074mm, 1-2% of mineral powder, and 6-7% of oilstone. The aggregate is limestone particles, the mineral powder is S95 grade mineral powder, and the asphalt is 70#A grade. The performance requirements of the mixture are porosity of 2-4%, stability greater than 8KN, and flow value of 2-4mm.

[0028] The adhesive is any one of emulsified asphalt, modified emulsified asphalt, sandy asphalt mastic, resin modified asphalt adhesive, and asphalt mortar.

[0029] The grouting sealing material is any one of cement mortar, emulsified asphalt, modified emulsified asphalt, and sandy asphalt mastic.

[0030] The height of the expanded core section 81 at the lower part of the asphalt concrete core wall 8 is 3.5m, and the width in the downstream direction narrows from 3m to 1.5m. The cross-sectional width of the core wall at the upper part of the expanded core section is 1.5m, and the cross-sectional width of the upper part of the core wall within 10m from the lower end of the dam crest is 0.9m. The upper end of the asphalt concrete core wall is connected to the rear part of the lower end of the wave-breaking wall 9 located at the dam crest. The width of the first and second transition layers on both sides of the asphalt concrete core wall remains unchanged and the height is the same, and the width of the concrete grouting stone wall 10 remains unchanged and the height is also the same.

[0031] The core wall expansion section 81 at the lower part of the asphalt concrete core wall is located on the concrete base 14 in the concrete foundation pit 18. A curtain grouting reinforcement area 13 is provided between the compaction area 6 at the lower end of the concrete base and the rock layer 1 at the lower end. A plurality of reinforced concrete pillars 15 are provided at intervals at the lower end of the concrete base. The lower end of each reinforced concrete pillar is inserted into the rock layer 1 at the lower end for at least 7 to 8 meters to stabilize the concrete foundation pit. A 2 cm thick sandy asphalt mastic 17 is provided between the lower end surface of the core wall expansion section at the lower part of the asphalt concrete core wall and the concrete base for bonding the two. A copper water stop plate 16 is longitudinally provided in the middle of the lower end of the core wall expansion section at the lower part of the asphalt concrete core wall and the middle of the concrete base for waterproofing.

[0032] A construction method for an asphalt concrete core wall structure of a super-high rockfill dam comprises the following steps: (1) An asphalt concrete brick prefabrication plant is built in a flat area near the super-high rockfill dam construction site. The production plant equipment includes batching and drying equipment, heating equipment, weighing and batching equipment, heating and mixing equipment, material dividing and metering bins, brick pressing equipment, brick storage warehouse, etc.

[0033] The brick pressing equipment is used to press the heated and stirred asphalt concrete material into asphalt concrete bricks. The brick pressing equipment is as follows: the four corners of the upper end of the base 32 are respectively fixed to the lower ends of the four guide columns 28, the upper ends of the four guide columns 28 are fixed to the four corners of the lower end of the top seat 22, and the upper end surface of the base inside each guide column is provided with a brick mold 26, and the four corners of the lower end of the brick mold 26 and the upper end surface of the base are supported and fixed by four legs 31 to fix the brick mold 26 on the upper end surface of the base. A concave brick material trough 25 is provided in the middle of the upper end surface of the brick mold, and a brick top steel plate 27 is provided on the bottom surface of the brick material trough 25. The center of the lower end surface of the brick top steel plate is connected to the telescopic rod 29 of the brick top hydraulic cylinder passing through the center of the lower end of the brick material trough, and the brick top hydraulic cylinder 30 is fixed on the base at the center of the lower end of the brick material trough. The four corners of the pressing plate 23 are axially arranged on the four guide columns at the upper end of the brick mold through the shaft sleeve 24, and the shaft sleeve can make the pressing plate 23 move up and down along the four guide columns 28. The brick pressing hydraulic cylinder 19 is arranged on the middle part of the upper end surface of the top seat plate, and the telescopic rod 20 of the brick pressing hydraulic cylinder passes downward through the top seat 22 and is connected to the middle part of the upper end surface of the pressing plate. A pressing die head 21 is arranged at the lower end of the pressing plate, and the shape and size of the pressing die head are adapted to the shape and size of the brick material trough.

[0034] When in use, the pressing plate and the pressing die head 21 at the lower end can move up and down along the four guide pillars 10 driven by the telescopic rod 20 of the brick pressing hydraulic cylinder. When the pressing die head moves down to the brick material trough at the upper end of the brick mold, the material used for an asphalt concrete brick in the brick material trough can be pressed into an asphalt concrete brick, and then the telescopic rod 20 of the brick pressing hydraulic cylinder moves upward and out of the brick material trough 25. At the same time, the brick-top hydraulic cylinder at the lower end of the brick mold is started to move the top brick steel plate 27 on the bottom surface of the brick material trough 25 upward through the telescopic rod 29 of the brick-top hydraulic cylinder, and the pressed asphalt concrete brick is also moved upward and out of the brick material trough, and transported to the brick storage warehouse for storage and standby.

[0035] The drying and drying equipment, heating equipment, weighing and batching equipment, heating and stirring equipment, material dividing and metering bins, and brick pressing equipment are all controlled by the PLC controller, related control components, and various operating circuit modules located in the electric control box. The outer panel of the electric control box is provided with control input components such as a control panel, a temperature control meter, a touch screen, and control buttons, which are used to coordinate the program control, transmission control, and information transmission of various mechanisms. Transmission control is the control of the position, speed, temperature, and adjustment of the transmission of each mechanism device, so that there is good information communication transmission between the various mechanisms and devices, such as the weighing sensor and PLC controller located on the weighing and batching equipment and the material dividing and metering bin to complete the weighing of the ingredients; the temperature sensor on the drying and drying equipment, heating equipment, and heating and stirring equipment cooperates with the PLC controller to complete the mixing and heating control of the ingredients; the pressure sensor on the brick pressing equipment (located on the die head) cooperates with the PLC controller to complete the pressure control of the ingredients, etc.; to ensure that the asphalt concrete bricks can reach the best quality control standards, the sensors, PLC controllers, control circuits, etc. are traditional components and circuits, so they will not be repeated.

[0036] (2) The cold aggregates constituting the asphalt concrete bricks are first placed in a drying and drying device for drying, then placed in a weighing and batching device for screening and metering, and then placed in a heating and mixing device together with mineral powder and asphalt for heating and mixing to form asphalt concrete materials. The exit temperature of the asphalt concrete materials is less than 120°C. The asphalt concrete materials pass through each material dividing and metering bin to form the amount of materials used for one asphalt concrete brick. The material dividing and metering bins place the amount of materials used for one asphalt concrete brick into the brick material groove of the brick mold in the brick pressing device, and start the brick pressing hydraulic cylinder. The telescopic rod of the brick pressing hydraulic cylinder extends and drives the die head at the lower end of the die pressing plate to squeeze down the material used for one asphalt concrete brick in the brick material groove of the brick mold, thereby completing the pressing and forming of the asphalt concrete bricks. That is, the brick pressing device presses asphalt concrete bricks of uniform weight, size, density and quality, and the pressed asphalt concrete bricks are placed in a brick storage warehouse for storage and standby use.

[0037] (3) The pressed asphalt concrete bricks are transported to the rockfill dam construction site, and the lines are marked and staked out before construction to ensure that the wall is aligned with the construction site. Figure 1The asphalt concrete core wall is formed by stacking prefabricated asphalt concrete bricks and adhesives. The stacking methods include the traditional one-long-one-tie, three-long-one-tie, and all-long-one. That is, the joints between the bricks in the one-long-one-tie are longitudinal joints and transverse joints respectively. All longitudinal bricks in one layer and all tie bricks in one layer are stacked alternately, and the vertical joints between the upper and lower layers are staggered by 1 / 4 brick length. The adhesive is located between the intersection surfaces of adjacent prefabricated asphalt concrete bricks. The prefabricated asphalt concrete bricks are arranged alternately. The horizontal integrity of the wall is ensured by the horizontal wall mark 33 and the tie bars 34 thereon. The flatness and verticality of the wall are checked by professional tools. If the temperature is below 0℃ when the asphalt concrete core wall is stacked, the adhesive should be insulated or heated to ensure the fluidity of the adhesive. The amount of adhesive used is about 4 to 6 kg per square meter.

[0038] (4) Each asphalt concrete brick core wall is 50m to 70m long and 0.60 to 0.8m high, which is a construction section. After the asphalt concrete brick core wall of the construction section is completed, a stone wall 10 with a width of 35 to 40cm is immediately built on both sides of the horizontal side of the asphalt concrete brick core wall of the section with polygonal stones with a diameter greater than 20cm close to the core wall surface, and a first transition layer 7 is laid close to the outer side of the stone wall and compacted. Cement mortar is filled in the brick joints of the stone wall. The weight ratio of cement to sand in the cement mortar is 1:1 to 1.5. Grouting sealing material is provided between the asphalt concrete core wall and the concrete grouting stone wall. The construction length and height of the stone wall and the first transition layer of the section are the same as those of the asphalt concrete brick core wall of the construction section. Thus, the two sides of the asphalt concrete brick core wall are sandwiched between the concrete grouting stone walls, and the two are seamlessly connected to form a soft and hard combination of anti-seepage supporting core wall structure.

[0039] Each transition layer needs to have high compressive strength, water resistance and weathering resistance. It is made of slightly new feldspar quartz sandstone mined from the material field. The width of the first transition layer on each side is 1.5m. The maximum particle size of the material in the first transition layer area does not exceed 80mm. The continuous grading weight ratio is 20-23% for particle size 60-80mm, 15-20% for particle size 40-60mm, 20-25% for particle size 20-40mm, 20-25% for particle size 5-20mm, 20-23% for particle size 0.25-5mm, and 4-5% for particle size 0.075-0.25mm. The design dry density of the first transition layer material is 2.14g / cm 3 , the corresponding porosity is 19%.

[0040] The first transition layer is used to improve the bonding strength between the concrete grouted stone wall and the asphalt concrete core wall and the rockfill area, so as to ensure the stability of the dam body.

[0041] (5) According to the length and height of the stone wall and the first transition layer, the second transition layer, the rockfill area, the slope gravel cushion layer and the dry stone slope protection 2 or the lattice grass slope protection 12 are constructed outward in sequence. The width of the second transition layer on each side is 3m. The maximum particle size of the second transition layer area shall not exceed 150mm. The continuous grading weight ratio is 10-15% for particle size 80-100mm, 15-20% for particle size 60-80mm, 15-20% for particle size 40-60mm, 20-25% for particle size 20-40mm, 10-15% for particle size 5-20mm, 20-25% for particle size 0.25-5mm, and 5-6% for particle size 0.075-0.25mm. The design dry density of the second transition layer area material is 2.14g / cm 3 , the corresponding porosity is 19%.

[0042] The second transition layer is used to further improve the bonding strength between the concrete grouted stone wall and the asphalt concrete core wall and the rockfill area to ensure the stability of the dam body.

[0043] The dam body located outside the second transition layer is the rockfill area 11. The maximum particle size of the rock in the rockfill area is 800mm. The content of particles smaller than 5mm in the rockfill area is less than 25%, and the content of particles smaller than 0.075mm is less than 5%. The rest are continuously graded. The design dry density of the rockfill area material is 2.11g / cm 3 , the corresponding porosity is 20%. The rockfill area is used to enhance the overall stability and anti-scouring ability of the dam body. The outer side of the dam body in the rockfill area is a trapezoidal slope. The outer side of the trapezoidal slope of the upstream rockfill area dam body is provided with a crushed stone cushion layer 4 with a thickness of 0.2m, and the outer side of the crushed stone cushion layer 4 is provided with a dry stone slope protection 2 with a thickness of 0.6m, which is used to further enhance the overall stability and anti-scouring ability of the dam body. The slope of the upstream dry stone slope protection 2 is 1:1.9. The outer side of the trapezoidal slope of the downstream rockfill area dam body is provided with a 0.4m thick lattice grass slope protection 12. The slope of the lattice grass slope protection is 1:1.7.

[0044] (6) Repeat steps (3) to (5) to carry out the construction of the next construction section. The construction sections can be constructed adjacent to each other or in sections. The rockfill dam construction site can be divided into several construction sections. The height difference between the construction sections is less than 1 m until the super-high asphalt concrete core wall rockfill dam is completed.

[0045] Example 2: Figure 7 As shown, the difference from Example 1 is that when there is no vertical compressive resistance requirement for the dam body, no concrete grouting stone wall may be provided on both sides of the asphalt concrete brick core wall. Then: In step (4): each asphalt concrete brick core wall is 50m to 70m long and 0.60 to 0.8m high as a construction section. After the asphalt concrete brick core wall of the construction section is completed, the first transition layer is immediately laid on the outer end surfaces of both sides of the asphalt concrete brick core wall of the section, and the first transition layer is compacted. The construction length and height of the first transition layer of the section are the same as the length and height of the asphalt concrete brick core wall of the construction section; (5) Based on the construction length and height of the first transition layer, the second transition layer, the rockfill area, the slope gravel cushion layer and the dry stone slope protection or lattice grass slope protection are constructed outward in sequence.

[0046] The rest is the same as that of Example 1, so it will not be described again.

[0047] The test data of the various embodiments of the present invention and the traditional asphalt concrete core wall dam are as follows: (1) Test conditions: the asphalt concrete core wall materials used in the comparative material and the various embodiments of the present invention are the same. The comparative material is an asphalt concrete core wall prepared by a traditional method. The comparative material 1 is a field rolling type, and the comparative material 2 is a field casting type. The length of the test asphalt concrete core wall is 10m, the width is 0.9m, and the height is 1.8m. The first transition zone with a width of 0.5m and the same height is set on both sides of the test asphalt concrete core wall. The materials used in the first transition zone are the same. A water injection cofferdam is formed on one side of the comparative material and the asphalt concrete core wall of the various embodiments of the present invention. The water level in the cofferdam is 1.7m. The construction temperature is greater than zero degrees. The asphalt concrete core wall data measured after 60 days are as follows.

[0048] (1) Table 1:

[0049] (2) The tensile strength is determined by direct tensile test, the density and water permeability coefficient are measured on site, and the compressive strength is determined by uniaxial compression test. Table 1 shows that various indicators of the asphalt concrete core wall of each embodiment of the present invention are better than various indicators of the traditional asphalt concrete core wall. Since the pressing and forming of the asphalt concrete bricks constituting the asphalt concrete core wall is completed in the prefabrication plant with uniform weight, size, density and quality, it can effectively ensure that the asphalt concrete core wall meets the design standards, and the asphalt concrete core wall is not affected by the climate during construction.

[0050] What is described above is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An asphalt concrete core wall structure of a super-high rockfill dam, consisting of a rockfill area, a concrete base and a slope gravel layer, characterized in that: The asphalt concrete core wall is made of a number of prefabricated asphalt concrete bricks and an adhesive that can bond the prefabricated asphalt concrete bricks together. Each prefabricated asphalt concrete brick is mechanically pressed in the prefabrication plant according to the set weight, quality, size and density. The length, width and height ratio of each prefabricated asphalt concrete brick is 4:2:

1. The two sides of the asphalt concrete core wall are provided with a concrete grouting stone wall, a first transition layer and a second transition layer in sequence; or the two sides of the asphalt concrete core wall are provided with a first transition layer and a second transition layer in sequence; Grouting sealing material is provided between the asphalt concrete core wall and the concrete grouted stone wall.

2. The asphalt concrete core wall structure of a super high rockfill dam according to claim 1, characterized in that: The prefabricated asphalt concrete bricks are stacked in an interlaced manner to form an asphalt concrete core wall.

3. The asphalt concrete core wall structure of a super high rockfill dam according to claim 1, characterized in that: The prefabricated asphalt concrete brick is a rectangular body, and the length, width and height of the prefabricated asphalt concrete brick are preferably 0.8m, 0.4m, 0.2m, or 1.6m, 0.8m in width and 0.4m in height.

4. The asphalt concrete core wall structure of a super high rockfill dam according to claim 1, characterized in that: The mass-to-weight ratio of the prefabricated asphalt concrete brick material is: coarse aggregate with a particle size of 10-15 mm accounts for 10%, coarse aggregate with a particle size of 5-10 mm accounts for 22%, coarse aggregate with a particle size of 2.5-5 mm accounts for 23%, fine aggregate with a particle size of 0.074-2.5 mm accounts for 30%, sand with a particle size less than 0.074 mm accounts for 7%, mineral powder accounts for 1-2%, and the oilstone ratio is 6-7%.

5. The asphalt concrete core wall structure of a super high rockfill dam according to claim 1, characterized in that: The adhesive is any one of emulsified asphalt, modified emulsified asphalt, sandy asphalt mastic, resin modified asphalt adhesive, and asphalt mortar.

6. The asphalt concrete core wall structure of a super high rockfill dam according to claim 1, characterized in that: The grouting sealing material is any one of cement mortar, emulsified asphalt, modified emulsified asphalt, and sandy asphalt mastic.

7. A construction method for an asphalt concrete core wall structure of a super-high rockfill dam, characterized in that: The steps include: (1) Build an asphalt concrete brick prefabrication plant in a flat area near the super-high rockfill dam construction site. The production plant equipment includes batching and drying equipment, heating equipment, weighing and batching equipment, heating and mixing equipment, material dividing and metering warehouse, brick pressing equipment, and brick storage warehouse; (2) The cold aggregates constituting the asphalt concrete bricks are first placed in a drying and drying device for drying, then placed in a weighing and batching device for screening and metering, and then placed in a heating and mixing device together with mineral powder and asphalt for heating and mixing to form asphalt concrete materials. The asphalt concrete materials are heated and mixed together with mineral powder and asphalt to form asphalt concrete materials. The asphalt concrete materials are discharged from the warehouse at a temperature less than 120°C. The asphalt concrete materials are passed through various material dividing and metering bins to form the material quantity required for one asphalt concrete brick. The material dividing and metering bins place the material quantity required for one asphalt concrete brick into the brick material trough of the brick mold in the brick pressing device. The brick pressing device presses the asphalt concrete bricks into asphalt concrete bricks of uniform weight, size, density and quality. The pressed asphalt concrete bricks are placed in a brick storage warehouse for storage and standby use. (3) The pressed asphalt concrete bricks are transported to the rockfill dam construction site. Before construction, the lines are marked and set out to ensure that the wall is consistent with the construction drawing. The asphalt concrete core wall is built with prefabricated asphalt concrete bricks and adhesives. The adhesives are located between the intersections of adjacent prefabricated asphalt concrete bricks. The prefabricated asphalt concrete bricks are arranged in a staggered manner. Horizontal wall reinforcements are used to ensure the integrity of the wall. Professional tools are used to check the flatness and verticality of the wall. (4) Each asphalt concrete brick core wall is 50m to 70m long and 0.60 to 0.8m high, which is a construction section. After the asphalt concrete brick core wall of the construction section is completed, polygonal stones with a diameter greater than 20cm are immediately used to build a 35-40cm wide stone wall on both sides of the asphalt concrete brick core wall, close to the core wall surface, and the first transition layer is laid close to the outer side of the stone wall. The first transition layer is compacted, and cement mortar is filled in the brick joints of the stone wall. Grouting sealing materials are provided between the asphalt concrete core wall and the concrete grouting stone wall. The construction length and height of this section of the stone wall and the first transition layer are the same as the length and height of the asphalt concrete brick core wall of the construction section; Or: Each asphalt concrete brick core wall of 50m to 70m and 0.60 to 0.8m in height is a construction section. After the asphalt concrete brick core wall of the construction section is completed, the first transition layer is immediately laid on the outer end surfaces on both sides of the transverse side of the asphalt concrete brick core wall of the section, and the first transition layer is compacted. The construction length and height of the first transition layer of the section are the same as the length and height of the asphalt concrete brick core wall of the construction section; (5) According to the length and height of the stone wall and the first transition layer, the second transition layer, the rockfill area, the slope gravel cushion layer and the dry stone slope protection or lattice grass slope protection are constructed outwards in sequence; Or: construct the second transition layer, rockfill area, slope gravel cushion layer and dry stone slope protection or lattice grass slope protection in sequence outward according to the construction length and height of the first transition layer; (6) Repeat steps (3) to (5) to carry out the construction of the next construction section. The construction sections can be constructed adjacent to each other or in sections. The rockfill dam construction site can be divided into several construction sections. The height difference between the construction sections is less than 1 m until the super-high asphalt concrete core wall rockfill dam is completed.

8. The method according to claim 7, characterized in that: The brick pressing equipment is that the upper four corners of the base are respectively fixed to the lower ends of four guide columns, the upper ends of the four guide columns are fixed to the lower four corners of the top seat, the upper end surface of the base inside each guide column is provided with a brick mold, the four corners of the lower end of the brick mold and the upper end surface of the base are supported and fixed by legs, a concave brick trough is provided in the middle of the upper end surface of the brick mold, the bottom surface of the brick trough is provided with a top brick steel plate, the center of the lower end surface of the top brick steel plate is connected with the telescopic rod of the top brick hydraulic cylinder passing through the center of the lower end of the brick trough, the top brick hydraulic cylinder is fixed to the base at the center of the lower end of the brick trough, the four corners of the pressing plate are arranged on the four guide columns at the upper end of the brick mold through the shaft sleeve, the brick pressing hydraulic cylinder is arranged on the middle of the upper end surface of the top seat plate, the telescopic rod of the brick pressing hydraulic cylinder passes downward through the top seat and is connected with the middle of the upper end surface of the pressing plate, and a pressing die head is provided at the lower end of the pressing plate, and the shape and size of the pressing die head are adapted to the shape and size of the brick trough.

9. The method according to claim 7, characterized in that: The height of the core wall expansion section at the lower part of the asphalt concrete core wall is 3.5m, and the width in the downstream direction narrows from 3m to 1.5m. The cross-sectional width of the core wall at the upper part of the core wall expansion section is 1.5m, and the cross-sectional width of the upper part of the core wall within 10m from the lower end of the dam top is 0.9m.

10. The method according to claim 9, characterized in that: The width of the first transition layer on each side is 1.5m, the maximum particle size of the material in the first transition layer zone does not exceed 80mm, and the continuous grading weight ratio is 20-23% for particle size 60-80mm, 15-20% for particle size 40-60mm, 20-25% for particle size 20-40mm, 20-25% for particle size 5-20mm, 20-23% for particle size 0.25-5mm, and 4-5% for particle size 0.075-0.25mm.

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