Pervious concrete reinforcing agent and preparation method thereof

Abstract

The invention discloses a pervious concrete reinforcing agent which is prepared from modified kaolin, a water-retaining agent, an active filler and a sodium lignin sulfonate aqueous solution according to the substance mass ratio of (4-7): 3: (2-5): 5. According to the pervious concrete reinforcing agent, the modified kaolin is matched with the water-retaining agent, the active filler and the sodium lignin sulfonate aqueous solution, the compressive strength performance and the wear resistance of a product are optimized through blending and coordination of the raw materials, coordinated improvement of water permeability, strength and wear resistance is achieved, and meanwhile the product is remarkable in anti-freezing and weather-resistant stability effect.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete strengthening agents, and particularly to a permeable concrete strengthening agent and a preparation method thereof. Background Art

[0002] A sponge city is a new generation of urban rainwater management concept, which means that the city can be like a sponge and has good elasticity in adapting to environmental changes and coping with natural disasters brought by rainwater, and can also be called a "water elastic city".

[0003] In order to improve the water permeability of existing permeable concrete, it is easy to cause poor compressive strength performance and wear resistance of the product. It is difficult for the product to achieve coordinated improvement of water permeability, strength and wear resistance, and the product has poor frost resistance and weather resistance stability, which limits the use efficiency of the product.

[0004] The patent with publication number CN102515608B discloses a modified metakaolin-based concrete impermeability and crack resistance agent. The modified metakaolin is prepared according to the following steps: 1) Put the dried washed kaolin into a ball mill for grinding to obtain kaolin powder; 2) Calcinate the kaolin powder at a temperature of 500-1000°C for 0.5-6.0 hours to obtain metakaolin; 3) Put the metakaolin into a dispersing machine, add an organic modifier sulfamic acid salt or triethanolamine, and the mass ratio of metakaolin to the organic modifier is 5000∶1-100∶1, the dispersing time is 15-35 min, the contact angle is 50°-100°, and the specific surface area is 8000-15000 m2 / kg to obtain modified metakaolin. The modified metakaolin prepared by this technology can significantly reduce the drying shrinkage of concrete, enhance the bonding force between the cement paste and the coarse aggregate, thereby improving the compressive strength of the concrete, but at the same time it will reduce the porosity of the concrete and affect the water permeability effect.

[0005] The patent with publication number CN107572864B discloses a permeable concrete strengthening agent and a preparation method. The permeable concrete strengthening agent includes the following raw materials in parts by weight: 50-80 parts of alkanolamine organic matter, 40-60 parts of polyoxyethylene alkylphenol ether, 20-30 parts of polyol, 15-25 parts of calcium carbonate whisker, 10-20 parts of sodium lignosulfonate, 4-8 parts of dioctyl sulfosuccinate, 3-5 parts of rare earth aluminate coupling agent, 5-10 parts of sodium tripolyphosphate, and 1-3 parts of antioxidant. The formula of this technology uses sodium lignosulfonate and dioctyl sulfosuccinate as water reducing agents, and has a significant water reducing effect. It can effectively prevent the agglomeration of cement particles, improve the fluidity of concrete processing, reduce the amount of cement used, and save costs. However, in this technical solution, alkanolamine organic matter and polyoxyethylene alkylphenol ether organic compounds are used as the main raw materials, making the cost of the strengthening agent relatively high. Summary of the Invention

[0006] In view of the defects of the prior art, the object of the present invention is to provide a permeable concrete reinforcing agent and a preparation method thereof to solve the problems raised in the above background technology.

[0007] The present invention solves the technical problem by adopting the following technical solution: The invention provides a permeable concrete reinforcing agent, which comprises modified kaolin, a water retaining agent, an active filler and a sodium lignin sulfonate aqueous solution, wherein the mass ratio of the modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution is (4-7):3:(2-5):5.

[0008] Preferably, the mass fraction of the sodium lignin sulfonate aqueous solution is 5-8%, and the water retaining agent is hydroxyethyl cellulose.

[0009] Preferably, the preparation method of the modified kaolin is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 55-60°C for 1h to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 1 to 3 parts of silane coupling agent KH550, 2 to 4 parts of 4% by mass urea solution and 3 to 5 parts of zeolite to 5 to 8 parts of lanthanum chloride solution, stir evenly, and obtain zeolite liquid; S02b: 4-7 parts of sepiolite fiber and 2-4 parts of nano-alumina are blended and added into 5-8 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber solution; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

[0010] Preferably, the mass fraction of the potassium permanganate solution is 5 to 8%; the mass fraction of the lanthanum chloride solution is 2 to 5%.

[0011] Preferably, the ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment is performed for 20 minutes; the stirring speed of the stirring modification treatment is 550-650r / min, and the stirring is performed for 1 hour.

[0012] Preferably, the preparation method of the active filler is: S101, Preparation of Nano-TiO2 Liquid: Add 2 to 4 parts of pretreated nano titanium dioxide and 2 to 3 parts of hydrotalcite into 5 to 8 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 3 to 5 parts of volcanic rock and 1 to 2 parts of nano-silica sol into 5 to 8 parts of nano-titanium dioxide liquid, then adding 2 to 4 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

[0013] Preferably, the mass fraction of the sodium silicate solution is 5 to 8%.

[0014] Preferably, the pre-treated nano-titanium dioxide is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 110-130° C. for 1 hour, and cooling to room temperature after sintering.

[0015] The invention also provides a preparation method of a permeable concrete reinforcing agent, comprising the following steps: fully blending and ball-milling modified kaolin, a water retaining agent, an active filler and a sodium lignin sulfonate aqueous solution, and then filtering and drying to obtain the permeable concrete reinforcing agent.

[0016] Preferably, the blending is fully ball-milled at a speed of 1000 to 1500 r / min, and the ball milling is performed for 2 hours.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) The permeable concrete enhancer of the present invention uses modified kaolin, a water-retaining agent, an active filler, and an aqueous solution of sodium lignin sulfonate. By blending and coordinating the raw materials, the compressive strength and wear resistance of the product are optimized, and the coordinated improvement of water permeability, strength, and wear resistance is achieved. At the same time, the product has significant antifreeze and weathering stability effects; (2) The aqueous solution of sodium lignin sulfonate in the permeable concrete enhancer of the present invention acts as a water reducer, which reduces the agglomeration effect of cement particles, reduces water consumption and maintains the stability of the through pores in the concrete; the adsorption and dispersion of modified kaolin avoids pore blockage caused by excessive water reducer while optimizing pore connectivity; hydroxyethyl cellulose acts as a water retaining agent, which delays the cement hydration process and reduces shrinkage cracks by retaining water, and the flexible structure of its molecular chain can absorb impact energy and improve the toughness of concrete; (3)The kaolin is treated with potassium permanganate solution, enhancing the activity of surface hydroxyl groups and optimizing its activity efficiency. Then, with the improvement of preheating, the activity of kaolin is enhanced. Meanwhile, surface improvement treatment is carried out through stirring with the modification liquid. In the modification liquid, the fiber liquid and zeolite liquid are ultrasonically improved and coordinated. The fiber liquid is prepared by mixing and adjusting with the sodium citrate solution obtained by blending sepiolite fiber and nano-aluminum oxide. Then, it is further adjusted and improved with the zeolite liquid. The raw materials such as zeolite in the zeolite liquid cooperate and coordinate with each other. The prepared modified kaolin optimizes the performance coordination of the product in the system, improves the interfacial bonding strength with the cement matrix and the performance stability; through the composite modification of silane coupling agent KH550 and sepiolite fiber, a microstructural structure with hierarchical pores is formed. By introducing nano-aluminum oxide to fill the micropores, the proportion of ineffective pores is reduced, making the water permeation path more efficient, and the potential for improving the water permeability coefficient is higher than that of the ordinary kaolin enhancement scheme; at the same time, the modified kaolin enhances the bonding strength between the cement matrix and the aggregate through the interfacial strengthening effect of silane coupling agent KH550 and sepiolite fiber. Combining with the nano-filling effect of nano-aluminum oxide, the compressive strength is improved. The sepiolite fiber forms a three-dimensional network structure inside the concrete, inhibiting the wear expansion by bridging cracks. Meanwhile, the water-reducing effect of sodium lignosulfonate reduces the surface bleeding, improving the surface density and wear resistance; (4) The active filler realizes its functions through the "physical-chemical synergistic effect": the porous framework of volcanic rock provides physical support, the nanomaterials (TiO2, SiO2) exert surface effect and small-size effect, and the sodium silicate-hydrotalcite system forms an alkaline microenvironment, jointly promoting the continuous reaction of pozzolanic active components, and finally forming a dense network structure, which significantly improves the mechanical properties while ensuring water permeability. Specifically, the active filler is prepared by mixing and improving volcanic rock, nano-silica sol, nano-titanium dioxide solution and citric acid. The pre-treated nano-titanium dioxide, hydrotalcite and sodium silicate solution in the nano-titanium dioxide solution are blended and formulated, and the pre-treated nano-titanium dioxide is improved by sintering nano-titanium dioxide and yttrium oxide at 110-130 °C. Through the coordinated cooperation and blending improvement among raw materials, the active filler is a composite formula containing volcanic rock (porous adsorption) and nano-silica sol (promoting hydration reaction). Through the secondary hydration reaction between volcanic rock and cement hydration products, enhancing substances such as C-S-H gel are generated, filling pores and increasing strength. The high surface activity of nano-silica sol can react quickly with cement hydration products, promoting the hydration process and refining the microstructure. The sodium silicate solution, as an alkaline activator, activates the latent cementitious components in volcanic rock, improving the pozzolanic reactivity, and the effect of increasing the compressive strength is better than that of a single mineral admixture; the active filler contains pre-treated nano-titanium dioxide and volcanic rock. Nano-titanium dioxide improves surface wear resistance through high-hardness nano-particles (TiO2), and volcanic rock buffers wear stress through pores, and the wear resistance is significantly higher than that of the traditional silica fume reinforcement scheme. The active filler is further combined with modified kaolin, and through the coordinated cooperation among raw materials, the product performance has excellent coordination, and the water permeability, strength and wear resistance of the product are coordinately improved. At the same time, the product has remarkable anti-freezing and weather resistance stability effects. Detailed implementation mode

[0018] The following combines specific embodiments to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] The water-permeable concrete enhancer of this embodiment, the concrete enhancer is modified kaolin, water retention agent, active filler and sodium lignosulfonate aqueous solution, and the mass ratio of modified kaolin, water retention agent, active filler and sodium lignosulfonate aqueous solution is (4-7):3:(2-5):5.

[0020] The mass fraction of the sodium lignosulfonate aqueous solution in this embodiment is 5-8%.

[0021] The preparation method of the modified kaolin in this embodiment is: S01: Stir the kaolin thoroughly in a sufficient amount of potassium permanganate solution, then wash it with water, filter it by suction, and dry it. Preheat the dried kaolin at 55 - 60 °C for 1 h to obtain preheated kaolin. S02: Preparation of the modification solution: S02a: Add 1 - 3 parts of silane coupling agent KH550, 2 - 4 parts of 4% urea solution by mass, and 3 - 5 parts of zeolite into 5 - 8 parts of lanthanum chloride solution, stir evenly to obtain zeolite solution. S02b: Blend 4 - 7 parts of sepiolite fiber and 2 - 4 parts of nano - alumina and add them into 5 - 8 parts of sodium citrate solution, stir thoroughly to obtain fiber solution. S02c: Ultrasonically treat the fiber solution and the zeolite solution according to a weight ratio of 3:5 to obtain the modification solution. S03: Stir and modify the preheated kaolin and the modification solution according to a weight ratio of 3:5. After stirring, filter by suction and dry to obtain modified kaolin.

[0022] In this example, the mass fraction of the potassium permanganate solution is 5 - 8%; the mass fraction of the lanthanum chloride solution is 2 - 5%.

[0023] In this example, the ultrasonic power of the ultrasonic treatment is 350 - 400 W, and the ultrasonic treatment lasts for 20 min; the stirring speed of the stirring and modification treatment is 550 - 650 r / min, and the stirring lasts for 1 h.

[0024] The preparation method of the active filler in this example is as follows: S101: Preparation of nano - titanium dioxide solution: Add 2 - 4 parts of pretreated nano - titanium dioxide and 2 - 3 parts of hydrotalcite into 5 - 8 parts of sodium silicate solution and stir evenly to obtain nano - titanium dioxide solution. S102: Add 3 - 5 parts of volcanic rock and 1 - 2 parts of nano - silica sol into 5 - 8 parts of nano - titanium dioxide solution, then add 2 - 4 parts of citric acid, stir thoroughly, and finally filter by suction and dry to obtain the active filler.

[0025] In this example, the mass fraction of the sodium silicate solution is 5 - 8%.

[0026] In this example, the pretreated nano - titanium dioxide is prepared by mixing nano - titanium dioxide and yttrium oxide according to a weight ratio of 5:2, sintering at 110 - 130 °C for 1 h, and after sintering, cooling to room temperature.

[0027] The preparation method of the permeable concrete enhancer in this example includes the following steps: Blend the modified kaolin, water - retaining agent, active filler, and aqueous solution of lignosulfonate thoroughly by ball - milling, then filter by suction and dry to obtain the permeable concrete enhancer.

[0028] The blending ball milling in this embodiment has a full ball milling speed of 1000-1500 r / min and the ball milling is performed for 2 hours.

[0029] Example 1. The permeable concrete reinforcer of this embodiment is modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution, wherein the mass ratio of modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution is 4:3:2:5.

[0030] The mass fraction of the sodium lignin sulfonate aqueous solution in this embodiment is 5%.

[0031] The preparation method of the modified kaolin of this embodiment is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 55°C for 1 hour to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 1 part of silane coupling agent KH550, 2 parts of 4% by mass urea solution and 3 parts of zeolite to 5 parts of lanthanum chloride solution, stir evenly to obtain zeolite solution; S02b: 4 parts of sepiolite fiber and 2 parts of nano-alumina are blended and added into 5-8 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber solution; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

[0032] The mass fraction of the potassium permanganate solution in this embodiment is 5%; the mass fraction of the lanthanum chloride solution is 2%.

[0033] The ultrasonic power of the ultrasonic treatment in this embodiment is 350W, and the ultrasonic treatment lasts for 20 minutes. The stirring speed of the stirring modification treatment is 550r / min, and the stirring is for 1 hour.

[0034] The preparation method of the active filler of this embodiment is: S101, Preparation of Nano-TiO2 Liquid: Add 2 parts of pretreated nano titanium dioxide and 2 parts of hydrotalcite into 5 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 3 parts of volcanic rock and 1 part of nano-silica sol into 5 parts of nano-titanium dioxide liquid, then adding 2 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

[0035] The mass fraction of the sodium silicate solution in this embodiment is 5%.

[0036] The pretreated nano-titanium dioxide in this embodiment is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 110° C. for 1 hour, and cooling to room temperature after sintering.

[0037] The preparation method of the permeable concrete reinforcing agent of this embodiment comprises the following steps: fully blending and ball-milling the modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution, and then filtering and drying to obtain the permeable concrete reinforcing agent.

[0038] The blending process of this embodiment is performed at a full milling speed of 1000 r / min for 2 h.

[0039] Example 2. The permeable concrete reinforcer of this embodiment comprises modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution, wherein the mass ratio of the modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution is 7:3:5:5.

[0040] The mass fraction of the sodium lignin sulfonate aqueous solution in this embodiment is 8%.

[0041] The preparation method of the modified kaolin of this embodiment is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 60°C for 1h to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 3 parts of silane coupling agent KH550, 4 parts of 4% by mass urea solution and 5 parts of zeolite to 8 parts of lanthanum chloride solution, stir evenly to obtain zeolite liquid; S02b: 7 parts of sepiolite fiber and 4 parts of nano-alumina are blended and added into 8 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber solution; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

[0042] The mass fraction of the potassium permanganate solution in this embodiment is 8%; the mass fraction of the lanthanum chloride solution is 5%.

[0043] The ultrasonic power of the ultrasonic treatment in this embodiment is 400W, and the ultrasonic treatment is performed for 20 minutes; the stirring speed of the stirring modification treatment is 650r / min, and the stirring is performed for 1 hour.

[0044] The preparation method of the active filler of this embodiment is: S101, Preparation of Nano-TiO2 Liquid: Add 4 parts of pretreated nano titanium dioxide and 3 parts of hydrotalcite into 8 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 5 parts of volcanic rock and 2 parts of nano-silica sol into 8 parts of nano-titanium dioxide liquid, then adding 4 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

[0045] The mass fraction of the sodium silicate solution in this embodiment is 8%.

[0046] The pretreated nano-titanium dioxide in this embodiment is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 130° C. for 1 hour, and cooling to room temperature after sintering.

[0047] The preparation method of the permeable concrete reinforcing agent of this embodiment comprises the following steps: fully blending and ball-milling the modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution, and then filtering and drying to obtain the permeable concrete reinforcing agent.

[0048] The blending process of this embodiment is performed at a full milling speed of 1500 r / min for 2 h.

[0049] Example 3. The permeable concrete reinforcer of this embodiment comprises modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution, wherein the mass ratio of modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution is 5.5:3:3.5:5.

[0050] The mass fraction of the sodium lignin sulfonate aqueous solution in this embodiment is 6.5%.

[0051] The preparation method of the modified kaolin of this embodiment is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 57°C for 1 hour to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 2 parts of silane coupling agent KH550, 3 parts of 4% urea solution by mass and 4 parts of zeolite to 6.5 parts of lanthanum chloride solution, stir evenly, and obtain zeolite liquid; S02b: 5.5 parts of sepiolite fiber and 3 parts of nano-alumina are blended and added into 6.5 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber liquid; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

[0052] The mass fraction of the potassium permanganate solution in this embodiment is 6.5%; the mass fraction of the lanthanum chloride solution is 3.5%.

[0053] The ultrasonic power of the ultrasonic treatment in this embodiment is 375W, and the ultrasonic treatment is performed for 20 minutes. The stirring speed of the stirring modification treatment is 600r / min, and the stirring is performed for 1 hour.

[0054] The preparation method of the active filler of this embodiment is: S101, Preparation of Nano-TiO2 Liquid: Add 3 parts of pretreated nano titanium dioxide and 2.5 parts of hydrotalcite to 6.5 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 4 parts of volcanic rock and 1.5 parts of nano-silica sol into 6.5 parts of nano-titanium dioxide liquid, then adding 3 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

[0055] The mass fraction of the sodium silicate solution in this embodiment is 6.5%.

[0056] The pretreated nano-titanium dioxide in this embodiment is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 120° C. for 1 hour, and cooling to room temperature after sintering.

[0057] The preparation method of the permeable concrete reinforcing agent of this embodiment comprises the following steps: fully blending and ball-milling the modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution, and then filtering and drying to obtain the permeable concrete reinforcing agent.

[0058] The blending process of this embodiment is performed at a full milling speed of 1250 r / min for 2 h.

[0059] Example 4. The permeable concrete reinforcing agent of this embodiment is modified kaolin, hydroxyethyl cellulose, hydroxyethyl cellulose and sodium lignin sulfonate aqueous solution, wherein the mass ratio of modified kaolin, water retaining agent and active filler and sodium lignin sulfonate aqueous solution is 5:3:2:5.

[0060] The mass fraction of the sodium lignin sulfonate aqueous solution in this embodiment is 6%.

[0061] The preparation method of the modified kaolin of this embodiment is: S01: Stir the kaolin thoroughly in a sufficient amount of potassium permanganate solution, then wash it with water, filter it by suction, and dry it. Preheat the dried kaolin at 57 °C for 1 h to obtain preheated kaolin; S02: Preparation of the modification solution: S02a: Add 1.5 parts of silane coupling agent KH550, 2 parts of 4% urea solution by mass, and 4 parts of zeolite to 6 parts of lanthanum chloride solution, stir evenly to obtain zeolite solution; S02b: Add 5 parts of sepiolite fiber and 2 parts of nano-aluminum oxide into 6 parts of sodium citrate solution, stir thoroughly to obtain fiber solution; S02c: Ultrasonically treat the fiber solution and the zeolite solution according to a weight ratio of 3:5 to obtain the modification solution; S03: Stir and modify the preheated kaolin and the modification solution according to a weight ratio of 3:5. After stirring, filter by suction and dry to obtain modified kaolin.

[0062] In this example, the mass fraction of the potassium permanganate solution is 6%; the mass fraction of the lanthanum chloride solution is 3%.

[0063] In this example, the ultrasonic power of the ultrasonic treatment is 360 W, and the ultrasonic treatment lasts for 20 min; the stirring speed of the stirring modification treatment is 570 r / min, and the stirring lasts for 1 h.

[0064] The preparation method of the active filler in this example is as follows: S101: Preparation of nano-titanium dioxide solution: Add 3 parts of pretreated nano-titanium dioxide and 2 parts of hydrotalcite to 6 parts of sodium silicate solution, stir evenly to obtain nano-titanium dioxide solution; S102: Add 4 parts of volcanic rock and 2 parts of nano-silica sol to 6 parts of nano-titanium dioxide solution, then add 3 parts of citric acid, stir thoroughly, and finally filter by suction and dry to obtain the active filler.

[0065] In this example, the mass fraction of the sodium silicate solution is 6%.

[0066] The pretreated nano-titanium dioxide in this example is prepared by mixing nano-titanium dioxide and yttrium oxide according to a weight ratio of 5:2, sintering at 115 °C for 1 h, and after sintering, cooling to room temperature.

[0067] The preparation method of the permeable concrete enhancer in this example includes the following steps: Mix the modified kaolin, water retention agent, active filler, and sodium lignosulfonate aqueous solution thoroughly by ball milling, then filter by suction and dry to obtain the permeable concrete enhancer.

[0068] In this example, the ball milling speed for thorough ball milling is 1200 r / min, and the ball milling lasts for 2 h.

[0069] Example 5. The permeable concrete reinforcing agent of this embodiment comprises modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution, wherein the mass ratio of modified kaolin, hydroxyethyl cellulose, active filler and sodium lignin sulfonate aqueous solution is 6:3:4:5.

[0070] The mass fraction of the sodium lignin sulfonate aqueous solution in this embodiment is 7%.

[0071] The preparation method of the modified kaolin of this embodiment is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 58°C for 1h to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 2 parts of silane coupling agent KH550, 3 parts of 4% by mass urea solution and 4 parts of zeolite to 7 parts of lanthanum chloride solution, stir evenly to obtain zeolite solution; S02b: 6 parts of sepiolite fiber and 3 parts of nano-alumina are blended and added into 7 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber solution; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

[0072] The mass fraction of the potassium permanganate solution in this embodiment is 6%; the mass fraction of the lanthanum chloride solution is 3%.

[0073] The ultrasonic power of the ultrasonic treatment in this embodiment is 360W, and the ultrasonic treatment lasts for 20 minutes. The stirring speed of the stirring modification treatment is 570r / min, and the stirring is for 1 hour.

[0074] The preparation method of the active filler of this embodiment is: S101, Preparation of Nano-TiO2 Liquid: Add 3 parts of pretreated nano titanium dioxide and 2 parts of hydrotalcite into 7 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 4 parts of volcanic rock and 2 parts of nano-silica sol into 7 parts of nano-titanium dioxide liquid, then adding 3 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

[0075] The mass fraction of the sodium silicate solution in this embodiment is 7%.

[0076] In this embodiment, the pretreated nano-titanium dioxide is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 125°C for 1 h, and after the sintering is completed, cooling to room temperature.

[0077] The preparation method of the permeable concrete enhancer in this embodiment includes the following steps: mixing modified kaolin, water retainer, active filler, and sodium lignosulfonate aqueous solution thoroughly by ball milling, then filtering and drying to obtain the permeable concrete enhancer.

[0078] The ball milling speed for thorough ball milling in this embodiment is 1450 r / min, and the ball milling time is 2 h.

[0079] Comparative Example 1. It is different from Example 3 in that modified kaolin is not added.

[0080] Comparative Example 2. It is different from Example 3 in that the modification liquid is not added during the preparation of modified kaolin.

[0081] Comparative Example 3. It is different from Example 3 in that the fiber liquid is not added to the modification liquid.

[0082] Comparative Example 4. It is different from Example 3 in that sepiolite fiber and nano-aluminum oxide are not added to the fiber liquid.

[0083] Comparative Example 5. It is different from Example 3 in that the zeolite liquid is not added to the modification liquid.

[0084] Comparative Example 6. It is different from Example 3 in that urea solution and zeolite are not added to the zeolite liquid.

[0085] Comparative Example 7. It is different from Example 3 in that the silane coupling agent KH550 is not added to the zeolite liquid and water is used instead of the lanthanum chloride solution.

[0086] Comparative Example 8. It is different from Example 3 in that the active filler is not added.

[0087] Comparative Example 9. It is different from Example 3 in that volcanic rock and nano-silica sol are not added to the active filler.

[0088] Comparative Example 10. It is different from Example 3 in that the nano-titanium dioxide liquid is not added to the active filler.

[0089] Comparative Example 11. It is different from Example 3 in that hydrotalcite and sodium silicate solution are not added to the nano-titanium dioxide liquid.

[0090] Comparative Example 12 It is different from Example 3 in that pretreated nano-titanium dioxide is not added to the nano-titanium dioxide solution.

[0091] Comparative Example 13 It is different from Example 3 in that the pretreated nano-titanium dioxide is replaced by nano-titanium dioxide.

[0092] The enhancers of Examples 1-5 and Comparative Examples 1-13 are applied to concrete. The formula of the permeable concrete is as follows: the filler is ordinary Portland cement 42.5 (the dosage is 320 kg / m 3 )), the aggregate is single-sized granite (the particle size is 2-5 mm, and the dosage is 1500 kg / m 3 ), the water-cement ratio is 0.3, the aggregate-cement ratio is 4.0, and the dosage of the enhancer is 1.5% of the weight of the cement. Then the water permeability, strength and wear resistance are tested, and the frost resistance and weather resistance stability of the product are tested (the product is placed at -5°C for 24 h, and then irradiated at an ultraviolet intensity of 100 w / m 2 for 24 h).

[0093] The test methods are as follows: Water permeability coefficient test: It is tested according to the provisions of GJJ / T 135-2009 "Technical Specification for Permeable Cement Concrete Pavement"; Compressive strength test: It is tested in accordance with GB / T 50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete"; Wear resistance test: It is tested using GB / T 12988-2009 "Test Method for Wear Resistance of Inorganic Floor Materials".

[0094] The test results are as follows: It can be obtained from Examples 1-5 and Comparative Examples 1-13 that the products of Example 3 of the present invention have excellent water permeability, strength and wear resistance. At the same time, the performance of the products can be improved in a coordinated manner, and the frost resistance and weather resistance stability of the tested products are remarkable; When one of the modified kaolin and the active filler is not added to the product, the performance of the product shows an obvious deterioration trend. By using the two in a coordinated manner and jointly synergistically, the performance effect of the product is the most significant; When the modifying solution is not added during the preparation of the modified kaolin, the fiber solution is not added to the modifying solution, the sepiolite fiber, nano-aluminum oxide is not added to the fiber solution, the zeolite solution is not added to the modifying solution, the urea solution and zeolite are not added to the zeolite solution, the silane coupling agent KH550 is not added to the zeolite solution, and the lanthanum chloride solution is replaced by water, the performance of the product shows a deterioration trend to varying degrees. Only the modified kaolin modified by the modifying solution obtained by the specific method of the present invention has the most significant performance effect; Meanwhile, the performance effect of the product is the most remarkable when using the modified liquid made from the specific fiber liquid and zeolite liquid of the present invention; When volcanic rock, nano-silica sol are not added to the active filler, nano-titanium dioxide liquid is not added to the active filler, hydrotalcite and sodium silicate solution are not added to the nano-titanium dioxide liquid, pre-treated nano-titanium dioxide is not added to the nano-titanium dioxide liquid and pre-treated nano-titanium dioxide is replaced by nano-titanium dioxide, the performance of the product shows a trend of getting worse to varying degrees. The performance effect of the product is the most remarkable when using the active filler obtained by the specific method of the present invention. The performance effect of the product is the most remarkable when using the nano-titanium dioxide liquid made by the process of combining the pre-treated nano-titanium dioxide obtained by the specific method of the present invention with hydrotalcite and sodium silicate solution, etc.

[0095] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention.

[0096] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. Permeable concrete enhancer, characterized in that, The concrete reinforcing agent is modified kaolin, a water retaining agent, an active filler and a sodium lignin sulfonate aqueous solution, wherein the mass ratio of the modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution is (4-7):3:(2-5):

5.

2. The permeable concrete enhancer according to claim 1, characterized in that, The mass fraction of the sodium lignin sulfonate aqueous solution is 5-8%, and the water retaining agent is hydroxyethyl cellulose.

3. The permeable concrete enhancer according to claim 1, wherein The preparation method of the modified kaolin is: S01: Stir kaolin in a sufficient amount of potassium permanganate solution, then wash, filter and dry. Preheat the dried kaolin at 55-60°C for 1h to obtain preheated kaolin; S02: Preparation of modified solution: S02a: Add 1 to 3 parts of silane coupling agent KH550, 2 to 4 parts of 4% by mass urea solution and 3 to 5 parts of zeolite to 5 to 8 parts of lanthanum chloride solution, stir evenly, and obtain zeolite liquid; S02b: 4-7 parts of sepiolite fiber and 2-4 parts of nano-alumina are blended and added into 5-8 parts of sodium citrate solution, and stirred sufficiently to obtain a fiber solution; S02c: ultrasonically treating the fiber liquid and the zeolite liquid in a weight ratio of 3:5 to obtain a modified liquid; S03: The preheated kaolin and the modified liquid are stirred and modified in a weight ratio of 3:

5. After the stirring is completed, the mixture is filtered and dried to obtain modified kaolin.

4. The permeable concrete strengthening agent according to claim 3, wherein The mass fraction of potassium permanganate solution is 5-8%; the mass fraction of lanthanum chloride solution is 2-5%.

5. The permeable concrete strengthening agent according to claim 3, characterized in that, The ultrasonic power of the ultrasonic treatment is 350-400W, and the ultrasonic treatment is performed for 20 minutes. The stirring speed of the stirring modification treatment is 550-650r / min, and the stirring is performed for 1 hour.

6. The permeable concrete strengthening agent according to claim 1, characterized in that, The preparation method of the active filler is: S101, Preparation of Nano-TiO2 Liquid: Add 2 to 4 parts of pretreated nano titanium dioxide and 2 to 3 parts of hydrotalcite into 5 to 8 parts of sodium silicate solution and stir evenly to obtain nano titanium dioxide liquid; S102, adding 3 to 5 parts of volcanic rock and 1 to 2 parts of nano-silica sol into 5 to 8 parts of nano-titanium dioxide liquid, then adding 2 to 4 parts of citric acid, stirring thoroughly, and finally filtering and drying to obtain an active filler.

7. The permeable concrete enhancer according to claim 6, wherein The mass fraction of the sodium silicate solution is 5 to 8%.

8. The permeable concrete strengthening agent according to claim 6, characterized in that, The pre-treated nano-titanium dioxide is prepared by mixing nano-titanium dioxide and yttrium oxide in a weight ratio of 5:2, sintering at 110-130° C. for 1 hour, and cooling to room temperature after the sintering is completed.

9. The preparation method of the permeable concrete strengthening agent according to any one of claims 1 to 8, characterized in that, The following steps are involved: The modified kaolin, the water retaining agent, the active filler and the sodium lignin sulfonate aqueous solution are fully blended and ball-milled, and then filtered and dried to obtain a permeable concrete reinforcing agent.

10. The preparation method of the permeable concrete enhancer according to claim 9, characterized in that, The blending was ball-milled at a speed of 1000-1500 r / min for 2 h.

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