阅读说明：本技术 一种透水混凝土增强剂及其制备方法和应用 (Permeable concrete reinforcing agent and preparation method and application thereof ) 是由 李如林 赵斌 付士峰 周恩泽 刘东基 张广田 韩素玉 王飞 刘以臣 董泽华 高辉 于 2020-08-11 设计创作，主要内容包括：本发明涉及混凝土技术领域,具体公开一种透水混凝土增强剂及其制备方法和应用。所述透水混凝土增强剂,包含以下质量百分比的组分：硅灰60-70％,粉煤灰沸石粉8-15％,聚羧酸减水剂2-4％,可分散乳胶粉5-10％,甲基纤维素醚1-2％,十二烷基苯磺酸钠0.5-1％,纤维材料5-10％,早强剂4-7％和促凝剂1-3％。本发明的增强剂的加入使透水混凝土兼具良好的抗压强度、抗拉强度、透水系数、抗冻、抗蚀和耐热性能,具有优异的综合性能,可实现透水路面的快速修补及快速施工,满足透水路面修复时间短和快速恢复使用的要求。同时,本发明的增强剂以工业废弃物为原料,极大降低了增强剂的成本,降低环境压力,具有较高的经济效益。(The invention relates to the technical field of concrete, and particularly discloses a permeable concrete reinforcing agent, and a preparation method and application thereof. The pervious concrete reinforcing agent comprises the following components in percentage by mass: 60-70% of silica fume, 8-15% of fly ash zeolite powder, 2-4% of a polycarboxylic acid water reducing agent, 5-10% of dispersible latex powder, 1-2% of methyl cellulose ether, 0.5-1% of sodium dodecyl benzene sulfonate, 5-10% of a fiber material, 4-7% of an early strength agent and 1-3% of a coagulant. The reinforcing agent is added to ensure that the pervious concrete has good compressive strength, tensile strength, water permeability coefficient, frost resistance, corrosion resistance and heat resistance, has excellent comprehensive performance, can realize quick repair and quick construction of the pervious road surface, and meets the requirements of short repair time and quick recovery of the pervious road surface. Meanwhile, the reinforcing agent disclosed by the invention takes industrial waste as a raw material, so that the cost of the reinforcing agent is greatly reduced, the environmental pressure is reduced, and the economic benefit is higher.)

1. A pervious concrete reinforcing agent is characterized in that: comprises the following components in percentage by mass:

60-70% of silica fume, 8-15% of fly ash zeolite powder, 2-4% of a polycarboxylic acid water reducing agent, 5-10% of dispersible latex powder, 1-2% of methyl cellulose ether, 0.5-1% of sodium dodecyl benzene sulfonate, 5-10% of a fiber material, 4-7% of an early strength agent and 1-3% of a coagulant.

2. The pervious concrete reinforcing agent of claim 1, wherein: the particle size of the silica fume is 0.1-0.3 mu m; and/or

The polycarboxylate superplasticizer is polycarboxylate superplasticizer powder; and/or

The dispersible latex powder is EVA dispersible latex powder; and/or

The preparation method of the fly ash zeolite powder comprises the following steps: mixing 2-4mol/L NaOH solution with fly ash according to the proportion that 6-10mL NaOH solution is added into every 1g fly ash, stirring and heating at 90-120 ℃ under the microwave condition, carrying out reaction crystallization for 1-3h, and then sequentially carrying out suction filtration, drying and grinding to obtain the fly ash zeolite powder.

3. The pervious concrete reinforcing agent of claim 1, wherein: the fiber material is at least one of polyvinyl alcohol fiber and polypropylene fiber.

4. The pervious concrete reinforcing agent of claim 3, wherein: the fiber material is polyvinyl alcohol fiber.

5. The pervious concrete reinforcing agent of claim 1, wherein: the early strength agent is at least one of sodium sulfate, sodium acetate, triethanolamine and sodium nitrite.

6. The pervious concrete reinforcing agent of claim 5, wherein: the early strength agent consists of sodium sulfate and triethanolamine in a mass ratio of 3-5: 1-2.

7. The pervious concrete reinforcing agent of claim 1, wherein: the coagulant is at least one of sodium silicate, sodium aluminate, aluminum sulfate and lithium carbonate.

8. The method for preparing a permeable concrete reinforcing agent according to any one of claims 1 to 7, characterized in that: mixing the silica fume, the polycarboxylic acid water reducing agent, the dispersible latex powder, the fly ash zeolite powder, the methyl cellulose ether, the sodium dodecyl benzene sulfonate, the early strength agent and the coagulant, and stirring for 4-6min at the rotating speed of 400-600 r/min; then adding the fiber material, and stirring for 20-30min at the rotating speed of 400-600 r/min.

9. Pervious concrete paste comprising the reinforcing agent according to any one of claims 1 to 7, characterized in that: the composition comprises the following components in percentage by mass:

1400 portions of coarse aggregate 1350-.

10. The method for preparing a pervious concrete paste of claim 9, characterized in that: uniformly mixing the coarse aggregate and 40-60% of water according to the formula amount in parts by mass, adding the cement, the reinforcing agent and the rest of water according to the formula amount, and stirring for 2-3min at the speed of 100-.

Technical Field

The invention relates to the technical field of concrete, in particular to a pervious concrete reinforcing agent and a preparation method and application thereof.

Background

The pervious concrete is a porous structure concrete, is generally prepared by mixing and stirring coarse aggregate, a cementing material, water and an additive according to a certain proportion, is a novel environment-friendly and ecological road material, can be widely applied to the fields of parks, squares, parking lots, sidewalks, underground buildings, greening, sewage purification and the like, and can effectively solve the problems of urban rainwater waterlogging and groundwater recharge and release.

The reinforcing agent (additive) has the function of enabling cement slurry (gel material) wrapping the surface of the stone to fully wrap the stone (coarse aggregate), keeping the cement slurry still and improving the viscosity of the pervious concrete, thereby improving the strength of the pervious concrete in the later period and improving the mechanical property and the durability of the pervious concrete. Meanwhile, the reinforcing agent can also effectively enhance the compactness and strength of the cement paste, and improve the frost resistance of the pervious concrete. However, the pervious concrete prepared by the existing pervious concrete reinforcing agent usually has the following defects in the application process: 1) the pervious concrete has low early strength and is not suitable for quick repair and construction; 2) the permeable concrete has poor cohesiveness, so that the construction property of the permeable concrete is poor; 3) the shrinkage of the pervious concrete is large, so that the pervious concrete is easy to crack and has poor durability; 4) the cost is high and the economic benefit is poor.

Disclosure of Invention

Aiming at the problems of poor construction performance, easy cracking, poor durability and low economic benefit of pervious concrete prepared by the existing reinforcing agent due to low early strength, poor cohesiveness, large contractibility and high cost, the invention provides a pervious concrete reinforcing agent and a preparation method and application thereof.

In order to achieve the purpose of the invention, the embodiment of the invention adopts the following technical scheme:

a pervious concrete reinforcing agent comprises the following components in percentage by mass:

60-70% of silica fume, 8-15% of fly ash zeolite powder, 2-4% of a polycarboxylic acid water reducing agent, 5-10% of dispersible latex powder, 1-2% of methyl cellulose ether, 0.5-1% of sodium dodecyl benzene sulfonate, 5-10% of a fiber material, 4-7% of an early strength agent and 1-3% of a coagulant.

In the pervious concrete reinforcing agent provided by the invention, the silica fume is a byproduct recovered by dust removal equipment in ferroalloy smelting ferrosilicon and industrial silicon (metal silicon), and the silica fume is used for replacing part of gel material (cement) in concrete manufacturing, so that the manufacturing cost of concrete can be reduced, and the economic benefit is improved. Meanwhile, after the silica fume is used for replacing part of the gel material, compared with the method of singly using cement as the gel material, the compression strength of the concrete can be obviously improved. The fly ash zeolite powder is prepared by utilizing fly ash, can improve the later strength of the pervious concrete, and enables the pervious concrete to have certain adjusting capacity on the humidity in air and soil. The invention uses the compounding of a specific amount of silica fume and a small amount of fly ash zeolite powder as the raw material of the concrete reinforcing agent, and can improve the compressive strength of the concrete within 4-8h by 7-9 times compared with the case of singly using cement as a cementing material.

The water consumption for preparing the pervious concrete can be reduced by adding the polycarboxylic acid water reducing agent, the strength of the pervious concrete is rapidly improved, and the early strength of the concrete is favorably improved. The methyl cellulose ether has the functions of water retention and thickening, and can improve the construction property of the pervious concrete. The polycarboxylate superplasticizer and the methyl cellulose ether are used as raw materials of the reinforcing agent to act together, and the consumption of water can be obviously reduced on the premise of ensuring the early strength and the workability of the concrete.

The dispersible latex can increase the binding power and the coating performance of the cementing material and the aggregate in the pervious concrete. The sodium dodecyl benzene sulfonate can improve the frost resistance of the pervious concrete. The addition of the fiber material can improve the crack resistance and the impact resistance of the concrete and effectively improve the compressive toughness and the tensile strength of the concrete. The combined action of the dispersible latex, the sodium dodecyl benzene sulfonate and the fiber material can increase the inclusion of silica fume, and under the condition of larger usage amount of silica fume (obviously improving the compressive strength of concrete), the concrete has excellent water permeability, toughness, low temperature resistance, high temperature resistance, corrosion resistance and durability, and simultaneously can reduce the shrinkage and the cracking performance of the concrete, so that the concrete added with the reinforcing agent has the characteristic of 'breaking without scattering' when being damaged.

The early strength agent and the coagulant are combined with other components in the reinforcing agent, so that the aims of quick repair and quick construction of the permeable pavement can be fulfilled, and the requirements of shortening the repair time and quickly recovering the use of the permeable pavement are met.

The pervious concrete reinforcing agent provided by the invention has good compatibility with cementing materials such as cement, is suitable for silicate cement, sulphoaluminate cement, slag cement and the like, has good compatibility, and can ensure the water permeability and durability of pervious concrete under the condition of meeting the requirement of early strength of quick hardening of the concrete.

Preferably, the particle size of the silica fume is 0.1-0.3 μm.

Preferably, the polycarboxylate superplasticizer is polycarboxylate superplasticizer powder.

Preferably, the dispersible latex powder is EVA dispersible latex powder. The EVA dispersible latex powder can further increase the binding power of a cementing material and an aggregate in the pervious concrete, and improve the corrosion resistance and the durability of the concrete.

Preferably, the preparation method of the fly ash zeolite powder comprises the following steps: mixing 2-4mol/L NaOH solution with fly ash according to the proportion that 6-10mL NaOH solution is added into every 1g fly ash, stirring and heating at 90-120 ℃ under the microwave condition, carrying out reaction crystallization for 1-3h, and then sequentially carrying out suction filtration, drying and grinding to obtain the fly ash zeolite powder. The fly ash zeolite powder obtained by the preparation method contains high-activity silicon dioxide and silicon trioxide, can react with hydration products of cement to generate gelled substances, further improves the strength of the concrete and improves the workability of concrete mixtures.

Preferably, the fiber material is at least one of polyvinyl alcohol fiber and polypropylene fiber.

Preferably, the fiber material is polyvinyl alcohol fiber. The polyvinyl alcohol fiber is a synthetic fiber obtained by using polyvinyl alcohol as a raw material and adopting a specific processing technology, has the advantages of high strength, high elastic modulus, acid resistance and alkali resistance, can improve the property of pervious concrete by adding the polyvinyl alcohol fiber into a pervious concrete reinforcing agent, simultaneously improves the performances of crack resistance, impact resistance, durability, high temperature resistance and corrosion resistance of the pervious concrete, and has the characteristics of reducing the shrinkage of the concrete and improving the compression toughness.

Preferably, the early strength agent is at least one of sodium sulfate, sodium acetate, triethanolamine and sodium nitrite.

Preferably, the early strength agent consists of sodium sulfate and triethanolamine in a mass ratio of 3-5: 1-2. The early strength agent has the components in proportion, so that the early strength of the pervious concrete can be further improved, the compressive strength of the concrete within 4 hours can reach more than 20MPa, and the repair time and the recovery time of the pervious pavement are further shortened.

Preferably, the accelerator is at least one of sodium silicate, sodium aluminate, aluminum sulfate and lithium carbonate.

The invention also provides a preparation method of the pervious concrete reinforcing agent. The preparation method at least comprises the following steps:

mixing the silica fume, the polycarboxylic acid water reducing agent, the dispersible latex powder, the fly ash zeolite powder, the methyl cellulose ether, the sodium dodecyl benzene sulfonate, the early strength agent and the coagulant, and stirring for 4-6min at the rotating speed of 400-600 r/min; then adding the fiber material, and stirring for 20-30min at the rotating speed of 400-600 r/min.

The invention provides pervious concrete slurry containing the reinforcing agent, wherein the pervious concrete comprises the following components in percentage by mass:

1400 portions of coarse aggregate 1350-.

The invention also provides a preparation method of the pervious concrete slurry. The preparation method at least comprises the following steps: uniformly mixing the coarse aggregate and 40-60% of water according to the formula amount in parts by mass, adding the cement, the reinforcing agent and the rest of water according to the formula amount, and stirring for 2-3min at the speed of 100-.

Compared with the prior art, the preparation method of the pervious concrete has the characteristics of simple operation, no need of special equipment and short time, and the obtained concrete has extremely high construction performance.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.