High-performance pervious concrete and method for preparing the same

Abstract

The application belongs to the field of construction materials, and particularly discloses high-performance pervious concrete and a preparation method thereof.The aggregate in the high-performance pervious concrete is subjected to strengthening treatment, the concrete prepared from the aggregate has a 28d compressive strength of no less than 20.0MPa, even more than 30.0MPa, and a water permeability coefficient grade of no less than K2, meeting the relevant requirements of the pervious concrete, and being applicable to squares, road surfaces, parking lots and other places in application scenarios such as sponge cities, intelligent parks, low-carbon communities and ecological parks.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of construction materials, in particular to a high-performance pervious concrete and a preparation method and construction method thereof. BACKGROUND

[0002] Pervious concrete can realize rapid infiltration of rainwater (permeability coefficient is usually ≥1.0 mm / s) through the continuous interconnected pore structure formed by the accumulation of aggregate particles, which not only can alleviate urban waterlogging, but also can replenish groundwater and reduce the heat island effect, and is a key material for the construction of sponge cities. However, the current pervious concrete industry needs to use a large amount of natural aggregate, such as natural crushed stone of granite and basalt, as aggregate. Such aggregate needs to be processed through mining, crushing, and screening, which not only consumes a large amount of non-renewable mineral resources, but also causes ecological problems such as mountain destruction and vegetation loss. At the same time, the transportation cost of natural aggregate is high, which leads to the fact that the construction cost of pervious concrete is generally higher than that of ordinary concrete, thereby restricting its large-scale popularization and application.

[0003] Coal gangue is a solid waste generated in the process of coal mining and washing. Large amounts of coal gangue exposed to the open air not only occupy land (about 1 mu of land per 10,000 tons of coal gangue), but also cause soil, water, and air pollution through leaching, dusting, and other ways. Although coal gangue can be used as recycled aggregate to replace natural crushed stone, its performance defects seriously limit its application in pervious concrete. For example, the strength of coal gangue is usually low, and the original crushing value is generally 20%-35% (much higher than 10%-20% of natural crushed stone), and the uniaxial compressive strength is mostly 20-50 MPa, which is difficult to meet the requirements of high-performance concrete on the strength of aggregate. Secondly, coal gangue has poor interfacial compatibility. The surface of coal gangue is porous and rich in clay minerals, and has a negative charge. There is an obvious interfacial transition zone between the cement hydration products, which has high porosity and loose structure, and is easy to become a weak link of stress concentration, resulting in the decrease of concrete strength and the deterioration of durability; and in the process of use, the volume deformation of coal gangue caused by dry-wet cycle easily leads to the cracking of concrete.

[0004] To address the performance defects of coal gangue aggregate, existing technologies have explored various modification methods, but all have significant shortcomings. For example, while cement treatment of coal gangue can reduce the crushing value to some extent (by about 5%-10%), the bond between cement and the coal gangue surface is weak, the outer shell is prone to detachment, and the low density in the interfacial transition zone cannot be resolved, resulting in limited improvement in concrete strength (28-day compressive strength is often below 15MPa), making it difficult to meet the C20 and higher strength grade requirements. Treating the coal gangue surface with chemical reagents such as silane coupling agents and epoxy resins can improve interfacial adhesion, but this approach suffers from high costs, poor environmental performance (some reagents contain volatile organic compounds), and complex construction processes, making it unsuitable for large-scale industrial applications. While improving coal gangue performance through high-temperature calcination (800-1000℃) or mechanical grinding can increase aggregate strength, it is energy-intensive, easily leads to aggregate particle refinement, damages the pore structure of permeable concrete, and causes a significant decrease in permeability.

[0005] Furthermore, permeable concrete generally presents a trade-off between strength and permeability. Specifically, achieving high permeability (porosity ≥ 20%) necessitates reducing cement paste usage, leading to insufficient aggregate bond strength and a concrete compressive strength often below 15 MPa. Conversely, achieving high strength (≥ 20 MPa) requires increasing cement usage or reducing porosity, resulting in a loss of permeability (permeability coefficient < 1.0 mm / s). This contradiction is even more pronounced when using low-quality recycled aggregates such as coal gangue, severely limiting the application of permeable concrete in scenarios requiring strength, such as roads and parking lots.

[0006] The information in the background section is merely intended to illustrate the general background of the invention and should not be construed as an admission or implication in any way that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] This invention addresses the shortcomings of existing technologies by proposing the synergistic modification of coal gangue surface with cationic compounds and cement. This modification utilizes charge adsorption to construct a high-strength, highly adhesive composite shell. Simultaneously, it optimizes aggregate and reinforcing agent formulations, particularly in combination with anionic water-reducing agents, to achieve a synergistic improvement in the strength and permeability of coal gangue-based permeable concrete. This solves at least some of the technical problems in existing technologies. Specifically, this invention includes the following:

[0008] In a first aspect, the present invention provides a method for preparing high-performance permeable concrete, comprising the following steps:

[0009] (1) Spray the slurry containing cationic compounds and cement onto the coal gangue, stir it evenly, and after drying, form a high-strength shell layer of 50-100μm thickness on the surface of the aggregate to obtain reinforced coal gangue aggregate.

[0010] (2) Mix 250-450 parts by weight of cement, 1500-2000 parts by weight of reinforced coal gangue aggregate, and 5-30 parts by weight of reinforcing agent, then add water and control the water-cement ratio to 0.3-0.4 to prepare high-performance permeable concrete with a 28-day compressive strength of more than 20 MPa and a permeability coefficient of more than 1.5 mm / s.

[0011] In some embodiments, according to the method for preparing high-performance permeable concrete as described in the first aspect, the amount of slurry used in step (1) is 5-15% based on the weight of coal gangue, and the water-cement ratio is controlled to be 0.3-0.4.

[0012] In some embodiments, according to the method for preparing high-performance permeable concrete according to the first aspect, the cationic compound in the slurry is hexadecyltrimethylammonium bromide (CTAB) or polydiallyldimethylammonium chloride (PDADMAC), and its concentration is 0.2-1.5%.

[0013] In some embodiments, according to the method for preparing high-performance permeable concrete as described in the first aspect, the coal gangue is washed coal gangue and / or spontaneously combusting coal gangue.

[0014] In some embodiments, according to the method for preparing high-performance permeable concrete as described in the first aspect, the particle size of the reinforced coal gangue aggregate is in the range of 5-25 mm, and the crushing value is less than 25%.

[0015] In some embodiments, according to the method for preparing high-performance permeable concrete according to the first aspect, the reinforcing agent contains, based on the total weight of the reinforcing agent, 40-50 parts by weight of silica fume, 30-40 parts by weight of redispersible latex powder, 10-20 parts by weight of anionic water-reducing agent, 1-5 parts by weight of polyvinyl alcohol, 0.5-2 parts by weight of polypropylene fiber, and 1-5 parts by weight of retarder.

[0016] In some embodiments, according to the method for preparing high-performance permeable concrete as described in the first aspect, the anionic water-reducing agent is selected from polycarboxylate-based water-reducing agents and / or sulfonated lignin water-reducing agents.

[0017] In some embodiments, according to the method for preparing high-performance permeable concrete as described in the first aspect, step (2) further adds 25-40 parts by weight of fly ash.

[0018] In some embodiments, the method for preparing high-performance permeable concrete according to the first aspect further includes a curing step, which includes early curing with plastic film covering to retain moisture, mid-term curing with standard curing at a temperature of 20±2℃ and humidity ≥95%, and late-term natural curing.

[0019] In a second aspect, the present invention provides a high-performance permeable concrete, which is prepared by the method described in the first aspect.

[0020] A third aspect of the present invention provides a construction method comprising the preparation method of high-performance permeable concrete as described in the first aspect as a construction step.

[0021] In some embodiments, the construction method of the present invention includes applying high-strength coal gangue permeable concrete to municipal roads, parking lots, squares, ecological slope protection or urban drainage systems.

[0022] This invention develops a permeable concrete preparation technology that can take into account high strength, high permeability, low cost and environmental protection. It can not only solve the pollution problem of coal gangue solid waste, but also alleviate the pressure of natural aggregate resource shortage. It has important practical significance and application value for promoting the construction of sponge cities and the green transformation of the building materials industry. Detailed Implementation

[0023] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0024] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that the upper and lower limits of the range and each intermediate value between them are specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0025] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0026] In this paper, the term "coal gangue" refers to rock or its weathered products with a dry basis ash content >50% generated during coal mine construction, development and tunneling, coal mining, and coal washing. From a particle size perspective, tunneling coal gangue or washing coal gangue is preferred.

[0027] In order to meet the required performance requirements, the aggregate needs to be controlled within a specific range, usually below 20mm, such as 5-20mm, 5-10mm, 10-20mm, etc.

[0028] In this invention, different grades of aggregate can be obtained by vibrating sieves with different apertures or models. For example, depending on the raw materials, they can first be transported by conveyor belt to different vibrating sieves for initial screening. Then, the residue is crushed or pulverized as needed to obtain the desired aggregate or powder.

[0029] In this invention, the aggregate preparation step can be carried out using conventional methods, or new aggregate processing methods can be developed for this purpose. An exemplary method includes a crushing step, for example: feeding coal gangue with a particle size exceeding 200mm into a jaw crusher via a vibrating feeder and a gangue conveyor belt, with a target particle size of 10mm; after crushing, the aggregate is screened by a vibrating screen. Preferably, aggregate <10mm is conveyed to a 5mm mesh screen for filtration to obtain fine particles.

[0030] In some embodiments, the aggregate of the present invention further comprises other conventional aggregates, such as basalt, limestone, travertine, pumice, granite, and dolomite. The present invention may use one or more combinations of the above-mentioned aggregates. The proportion of other conventional aggregates in the total aggregate is generally 0-50%, for example, 10%, 20%, 30%, or 40%.

[0031] If the present invention is required to prepare permeable concrete with a strength of ≥20MPa, it is preferable to use a solution of washed coal gangue or self-combusting coal gangue + surface coating + low water-cement ratio, which can achieve a strength of 25-30MPa while maintaining good permeability, meeting the requirements of CJJ / T135-2009 "Technical Specification for Permeable Cement Concrete Pavement", and opening up a new way for the resource utilization of coal gangue.

[0032] Example 1

[0033] This example demonstrates the preparation of C20 grade permeable concrete (specifically for sidewalks / garden paths).

[0034] I. Strengthening the Preparation of Coal Gangue Aggregates

[0035] 1. Coal gangue raw material pretreatment

[0036] Raw material screening: Washed coal gangue (original crushing value 30±2%, uniaxial compressive strength 28±2MPa) was selected, and large impurities with a particle size >20mm and weathered stones were removed.

[0037] Crushing process: After crushing by a jaw crusher (model PE250×400, feed opening size 250×400mm, discharge particle size 5-20mm), the material is classified by a double-layer vibrating screen (screen hole size 10mm / 5mm) to screen out 5-10mm single-grade particles. The residue is returned to the crusher for secondary crushing.

[0038] Purification and cleaning: The graded coal gangue is put into a drum washing machine (speed 25r / min, washing water pressure 0.4MPa) to remove coal dust and clay particles (mud content ≤0.5%) attached to the surface. After rinsing, it is naturally drained for 2 hours.

[0039] Drying process: The product is fed into a box dryer (model TC-1, temperature control accuracy ±2℃) and dried in two stages: the first stage is drying at 60℃ for 2 hours to remove free water, and the second stage is drying at 80℃ for 4 hours to remove adsorbed water. The final moisture content is controlled to be ≤1% and the apparent density is ≥2500kg / m³.

[0040] Pre-treatment testing: Randomly select 3 groups of samples (5kg per group) and test the crushing value, mud content, and particle size distribution (5-10mm particles account for ≥95%). Unqualified products are reprocessed.

[0041] 2. Preparation of modified slurry

[0042] Raw material ratio: Mix according to the mass ratio CTAB: cement: water = 0.5: 100: 30.

[0043] Dispersion process: First, inject 30 parts of mixing water into a high-speed disperser (model SDF-400, speed 1500r / min), add 0.5 parts of CTAB, and ultrasonically disperse for 30 minutes to ensure that the cationic compound is completely dissolved.

[0044] Slurry mixing: Maintain the disperser speed at 800 rpm, slowly add 100 parts of cement, and mix for 3 minutes until a uniform paste-like slurry is formed. Control the slurry viscosity to 300-400 mPa. s (25℃, tested with NDJ-5S rotational viscometer, rotor speed 60r / min).

[0045] Slurry stability control: The prepared slurry must be used within 30 minutes. If the standing time exceeds 20 minutes, it needs to be stirred for another 30 seconds to prevent sedimentation; if the viscosity increases to >500 mPa... If necessary, add 1-2 parts water to adjust.

[0046] 3. Shell covering

[0047] A roller-type coating machine (model GZ-1000, roller length 1000mm, diameter 600mm, rotation speed 30r / min, tilt angle 5°) was used, equipped with a high-pressure spray system (nozzle type 0.8mm, spray pressure 0.5MPa, droplet size 50-100μm). 100 parts of pretreated coal gangue were fed into the roller, and the machine was started and rotated for 1 minute to ensure uniform particle distribution. The spray system was then activated to spray the modified slurry at a uniform speed (12% of the coal gangue mass) for 5 minutes, during which the roller was kept rotating to ensure uniform slurry adhesion. After the slurry spraying was completed, the roller continued to rotate for 10 minutes, utilizing the mutual friction between particles to tightly coat the surface with the slurry, forming a preliminary shell layer (40-50μm thick).

[0048] Shell curing and solidification: Transfer the coated coal gangue to a constant temperature curing chamber (model HBY-40B, temperature 70℃, relative humidity 60%) and cure for 2 hours to allow the slurry to initially solidify and prevent shell cracking. Constant temperature curing: Raise the temperature to 90℃ and maintain it for 4 hours to accelerate the cement hydration reaction, promote gel formation, and improve shell strength; record the temperature and humidity every hour during the curing process, with a deviation ≤ ±3℃.

[0049] Cooling treatment: Allow the shell to cool naturally to room temperature (cooling rate ≤10℃ / h) to avoid cracking due to thermal expansion and contraction caused by sudden temperature changes.

[0050] Shell performance testing: The shell thickness was measured (using a coating thickness gauge, model TT220, measurement accuracy ±1μm), with 3 points measured for each particle; the bond strength tester (model DNS-100) was used to test the bond strength between the shell and the aggregate, and the average value of 5 groups of samples was ≥2.8MPa.

[0051] Screening and grading: The cured reinforced aggregate is passed through a vibrating screen (4mm screen size) to remove particles with broken or detached shells (breakage rate ≤2%), and qualified products of 5-10mm are screened out.

[0052] Final performance test: Five finished product samples (5 kg per group) were randomly selected. The results showed that the average crushing value was 22 ± 0.5%, the shell integrity (coverage rate) was ≥ 98%, the shell shedding rate was 4.2%, and the water absorption rate was 2.5%-3.0%.

[0053] II. Preparation of Permeable Concrete

[0054] 1. Raw material ratio (parts by weight)

[0055]

[0056] 2. Mixing process

[0057] Preparation was carried out using a JS500 forced mixer (speed 30-40 r / min, mixing power 18.5 kW). First, reinforced coal gangue aggregate was added, and the mixer was started to dry mix for 30 seconds to remove surface dust; then cement, composite reinforcing agent, and fly ash were added in sequence, and dry mixing was continued for 3 minutes until the powder was evenly attached to the surface of the aggregate and there were no obvious dry powder lumps (visual inspection standard: the surface of the aggregate is uniformly gray and there is no accumulation of white cement particles).

[0058] Use a metering pump to precisely inject 80% of the mixing water and stir for 2 minutes. Stop the machine and observe the state of the mixture. If the slurry on the surface of the aggregate is too dry and dispersed particles appear, add the remaining water and continue stirring for 1-1.5 minutes. When the mixture does not clump, flow, or segregate, the aggregate surface is evenly coated with slurry (thickness 0.5-1mm), it can be formed into a ball by hand and then crumble when released, and it can naturally loosen and return to a granular state after falling to the ground.

[0059] 3. Maintenance process

[0060] Initial moisturizing and curing (0-24h): Immediately after molding, cover with double-layer curing material, control the ambient temperature at 15-30℃ (below 10℃, cover with a thermal insulation blanket), and maintain relative humidity ≥90% (use a hygrometer to monitor in real time and record every 4 hours); if the summer temperature is high (≥30℃), lift the film surface and spray mist water once every 6 hours to avoid surface dehydration and sanding.

[0061] Demolding and curing (after 24 hours): Wrap the mold with plastic film for demolding to avoid prying hard and causing damage to the edges and corners; after demolding, continue to cover with geotextile and transfer to the standard curing area. At this time, light watering is allowed to keep it moist, but direct rinsing is prohibited (to prevent cement slurry from flowing out and clogging the pores).

[0062] Standard curing (2-28 days): Curing environment temperature 20±2℃, relative humidity ≥95% (using standard curing box or constant temperature and humidity curing room), avoid external impact on the mixture during curing; on the 7th day, sampling can be used to test the compressive strength.

[0063] Post-construction maintenance (after 28 days): If used for outdoor paving, allow it to air dry naturally for 3-5 days after the curing period to ensure that the internal pores are dry and unobstructed before opening for use.

[0064] 4. Performance Testing

[0065]

[0066] Note: The testing was conducted in accordance with industry standard CJJ / T 135-2009 "Technical Specification for Permeable Cement Concrete Pavement" (2023 edition).

[0067] The permeable concrete in this embodiment is used in: urban sidewalks, park trails, and non-motorized vehicle lanes in residential areas.

[0068] Example 2

[0069] This example demonstrates the preparation of C25 grade permeable concrete (for parking lots / plazas).

[0070] I. Strengthening the Preparation of Coal Gangue Aggregates

[0071] Except for changing the weight ratio of CTAB:cement:water to 1:100:32 (increasing the CTAB content to enhance the shell adhesion) and controlling the shell thickness to be 70-80 μm for tight slurry coating, everything else was the same as in Example 1. The resulting reinforced coal gangue aggregate had a crushing value of 15 ± 0.3%, shell integrity (coating rate) ≥ 98%, shell detachment rate of 3.5%, and water absorption rate of 2.5%-3.0%.

[0072] II. Preparation of Permeable Concrete

[0073] Except for the raw material ratios (parts by weight) being changed to those shown in the table below, everything else is the same as in Example 1.

[0074]

[0075] Performance testing showed that the 28-day compressive strength was 32.5 MPa, the permeability coefficient was 2.5 mm / s, and the porosity was 19.8%. This meets the load requirements for parking small vehicles (≤5t).

[0076] Example 3

[0077] This embodiment is a preparation example of C30 grade permeable concrete (dedicated to non-motorized vehicle lanes / light vehicle lanes).

[0078] I. Strengthening the Preparation of Coal Gangue Aggregates

[0079] Except for the differences described below, everything else is the same as in Example 1.

[0080] Particle size adjustment: Screen 10-20mm single-stage coal gangue, and select impact crusher (model PF-1007, discharge particle size 10-20mm) to ensure that the particles are sharp and distinct (needle-shaped and flaky particles ≤8%).

[0081] Modified slurry: PDADMAC is used as a substitute, with a ratio of PDADMAC:cement:water of 1.2:100:32.

[0082] Coating process: Increase the roller speed to 35r / min and control the spraying time to make the shell thickness 75-85μm.

[0083] Curing process: First cure at 70℃ for 3 hours, then cure at 90℃ for 5 hours, with a shell bonding strength ≥3.2MPa.

[0084] The resulting reinforced coal gangue aggregate had an average crushing value of 14±0.3%, a shell integrity (coverage rate) of ≥98%, a shell detachment rate of 3.0%, and a water absorption rate of 2.5%-3.0%.

[0085] II. Preparation of Permeable Concrete

[0086] Except for the raw material ratios (parts by weight) being changed to those shown in the table below, everything else is the same as in Example 1.

[0087]

[0088] Performance testing showed a 28-day compressive strength of 38.2 MPa, a permeability coefficient of 2.2 mm / s, and a porosity of 16.5%. After 2 million fatigue cycles, the strength loss was ≤15%, making it suitable for light trucks (≤8t). Immersion in a 5% sodium sulfate solution for 6 months resulted in a strength loss of ≤8%, demonstrating excellent resistance to sulfate attack.

[0089] Comparative Example

[0090] Comparative Example 1: No coating treatment was performed, only pretreatment was done, the crushing value was 30±2%, and the rest was the same as in Example 1. The resulting concrete had a 28-day compressive strength of only 14.2 MPa, a permeability coefficient of 1.2 mm / s, and a 35% loss in frost resistance. The permeability coefficient of Comparative Example 1 is low (below the standard requirement of 1.5 mm / s), possibly because the unmodified coal gangue surface is porous, the residual mud content leads to poor pore connectivity, and it is easily broken under pressure.

[0091] Comparative Example 2: Except for the absence of cationic compounds and the use of a cement-water slurry with a weight ratio of 100:30 for coating, the results were identical to those of Example 1. The resulting particles exhibited a shell bonding strength of 1.8 MPa, a crushing value of 25.6%-27.3%, a 28-day concrete compressive strength of 18.5 MPa, a permeability coefficient of 1.8 mm / s, and a shell detachment rate of 12%. Although the permeability coefficient (1.8 mm / s) of Comparative Example 2 met the minimum standard, it was lower than that of Example 1 of this invention. This is because the uniformity of the single cement shell was poor, with some areas having excessively thick slurry that blocked the aggregate gaps, and the debris generated by the shell detachment further affected the permeability.

[0092] Comparative Example 3: Except for the absence of anionic water-reducing agent in the reinforcing agent, it was identical to Example 1. The resulting concrete had a 28-day compressive strength of 19.3 MPa and a permeability coefficient of 3.8 mm / s. Although the permeability coefficient of Comparative Example 3 was improved, its 28-day compressive strength was significantly lower than that of Example 1.

[0093] In summary, this invention reduces the crushing value of coal gangue by 8-15% and increases the shell bonding strength by more than 50% through synergistic modification of cationic compounds and cement. Simultaneously, by optimizing interfacial bonding with cationic compounds, the shell layer becomes thin and uniform (50-100 μm), ensuring strength, preventing damage to the pore structure, and further enhancing strength through electrostatic adsorption between the reinforced aggregate surface and cement during permeable concrete preparation. Ultimately, this achieves both a permeability coefficient of 1.6-3.5 mm / s and a compressive strength ≥20 MPa.

[0094] Although the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. Various adjustments or changes may be made to the exemplary embodiments described in this specification without departing from the scope or spirit of the invention. The scope of the claims should be interpreted in the broadest possible sense to cover all modifications and equivalent structures and functions.

Claims

1. A method for preparing high-performance permeable concrete, characterized in that, Includes the following steps: (1) A slurry containing a cationic compound and cement is sprayed onto coal gangue, stirred evenly, and dried to form a high-strength shell layer 50-100 μm thick on the surface of the aggregate, thereby obtaining reinforced coal gangue aggregate; wherein the cationic compound is hexadecyltrimethylammonium bromide or polydiallyldimethylammonium chloride; and (2) Mix 250-450 parts by weight of cement, 1500-2000 parts by weight of reinforced coal gangue aggregate, and 5-30 parts by weight of reinforcing agent, then add water and control the water-cement ratio to 0.3-0.4 to prepare high-performance permeable concrete with a 28-day compressive strength of more than 20 MPa and a permeability coefficient of more than 1.5 mm / s.

2. The method for preparing high-performance permeable concrete according to claim 1, characterized in that, In step (1), the amount of slurry used is 5-15% of the weight of coal gangue, and the water-ash ratio is controlled to be 0.3-0.

4.

3. The method for preparing high-performance permeable concrete according to claim 1, characterized in that, The concentration of cationic compounds in the slurry is 0.2-1.5%.

4. The method for preparing high-performance permeable concrete according to claim 1, characterized in that, The coal gangue is washed coal gangue and / or spontaneously combusting coal gangue.

5. The method for preparing high-performance permeable concrete according to claim 4, characterized in that, The reinforced coal gangue aggregate has a particle size in the range of 5-25mm and a crushing value of less than 25%.

6. The method for preparing high-performance permeable concrete according to claim 1, characterized in that, Based on the total weight of the reinforcing agent, the reinforcing agent contains 40-50 parts by weight of silica fume, 30-40 parts by weight of redispersible latex powder, 10-20 parts by weight of anionic water-reducing agent, 1-5 parts by weight of polyvinyl alcohol, 0.5-2 parts by weight of polypropylene fiber, and 1-5 parts by weight of retarder.

7. The method for preparing high-performance permeable concrete according to claim 6, characterized in that, The anionic water-reducing agent is selected from polycarboxylate-based water-reducing agents and / or sulfonated lignin water-reducing agents.

8. The method for preparing high-performance permeable concrete according to claim 1, characterized in that, Step (2) Add 25-40 parts by weight of fly ash.

9. A high-performance permeable concrete, which is prepared by the method described in any one of claims 1-8.

10. A construction method, characterized in that, The method for preparing high-performance permeable concrete according to any one of claims 1-8 is included as a construction step.

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