阅读说明：本技术 一种环保混凝土添加剂及其制备方法 (Environment-friendly concrete additive and preparation method thereof ) 是由 夏梅 于 2021-01-22 设计创作，主要内容包括：本发明适用混凝土制备技术领域,提供了一种环保混凝土添加剂及其制备方法,环保混凝土添加剂包括以下原料：焦磷酸型钛酸酯偶联剂、活性炭、聚酰胺纤维、改性磷石膏、改性硅灰石粉；本发明实施例提供的环保混凝土添加剂通过利用各组分的相互协同作用,大大增强了混凝土的抗压强度、抗渗等级、耐磨性、透水性,可显著改善透水混凝土中集料间的粘结性能,减少混凝土离析和泌水,在保证透水性能的基础上,显著提高透水混凝土强度和耐磨性能,确保工程的施工质量；同时使用实现了磷石膏的无害化利用,解决了环境污染问题,另一方面节约资源,变废为宝,降低生产成本,具有良好的经济和社会效益。(The invention is applicable to the technical field of concrete preparation, and provides an environment-friendly concrete additive and a preparation method thereof, wherein the environment-friendly concrete additive comprises the following raw materials: pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder; the environment-friendly concrete additive provided by the embodiment of the invention greatly enhances the compressive strength, impermeability grade, wear resistance and water permeability of concrete by utilizing the mutual synergistic effect of the components, can obviously improve the adhesive property among aggregates in pervious concrete, reduces concrete segregation and bleeding, obviously improves the strength and wear resistance of the pervious concrete on the basis of ensuring the water permeability, and ensures the construction quality of engineering; meanwhile, the use realizes the harmless utilization of the phosphogypsum, solves the problem of environmental pollution, saves resources, changes waste into valuable, reduces the production cost and has good economic and social benefits.)

1. The environment-friendly concrete additive is characterized by comprising the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder;

the preparation method of the modified wollastonite powder comprises the following steps: dispersing wollastonite powder in ethanol, adding silane coupling agent KH55, stirring at 40-60 deg.C for reaction for 3-5 hr, centrifuging, and oven drying at 70-80 deg.C for 15-18 hr to obtain modified wollastonite powder.

2. The environment-friendly concrete additive as claimed in claim 1, wherein the mass ratio of the wollastonite powder to the ethanol to the silane coupling agent KH55 is 5 (8-12) to 0.01-0.03.

3. The environment-friendly concrete additive as claimed in claim 1, wherein the preparation method of the modified phosphogypsum comprises the following steps: mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1: (1-1.5) preparing a modifier, adding the modifier into water, and mixing to obtain a mixed solution; and uniformly spraying the mixed solution into the phosphogypsum, carrying out aging reaction for 20 hours, and drying to obtain the modified phosphogypsum.

4. The environment-friendly concrete additive according to claim 3, wherein the weight ratio of the phosphogypsum to the modifier to the water is 10: (0.8-1.3): (1.5-3.5).

5. The environment-friendly concrete additive as claimed in claim 1, which comprises the following raw materials in parts by weight: 12-17 parts of pyrophosphoric acid type titanate coupling agent, 4-6 parts of activated carbon, 27-34 parts of polyamide fiber, 12-19 parts of modified phosphogypsum and 11-18 parts of modified wollastonite powder.

6. The environment-friendly concrete additive as claimed in claim 1, which comprises the following raw materials in parts by weight: 13-15 parts of pyrophosphoric acid type titanate coupling agent, 4-5 parts of activated carbon, 29-32 parts of polyamide fiber, 14-16 parts of modified phosphogypsum and 14-16 parts of modified wollastonite powder.

7. The environment-friendly concrete additive as claimed in claim 1, which comprises the following raw materials in parts by weight: 13 parts of pyrophosphoric acid type titanate coupling agent, 5 parts of activated carbon, 31 parts of polyamide fiber, 16 parts of modified phosphogypsum and 14 parts of modified wollastonite powder.

8. The method for preparing the environmentally friendly concrete additive according to any one of claims 1 to 7, comprising the steps of:

1) dispersing wollastonite powder in ethanol, adding a silane coupling agent KH55, stirring at 40-60 deg.C for reaction for 3-5 hr, centrifuging, and oven drying at 70-80 deg.C for 15-18 hr to obtain modified wollastonite powder; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1: 1-1.5, adding the modifier into water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use;

2) taking the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder;

3) uniformly stirring and mixing pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder in proportion, drying, adding into a ball mill, grinding for 15-25 minutes, and discharging;

4) adding polyamide fiber according to the amount, mixing uniformly, and bagging.

9. The preparation method of the environment-friendly concrete additive as claimed in claim 8, wherein in the step 3), the pyrophosphoric acid type titanate coupling agent, the activated carbon, the polyamide fiber, the modified phosphogypsum and the modified wollastonite powder are stirred for 3-5 hours at 40-55 ℃ in proportion.

Technical Field

The invention belongs to the field of concrete preparation, and particularly relates to an environment-friendly concrete additive and a preparation method thereof.

Background

In recent years, with rapid economic development and progress of integration of urban and rural areas, high-rise buildings have come into lives of people like bamboo shoots in the spring after rain, and the large basic engineering scale represented by the high-rise buildings is never closely related to concrete materials. Concrete, referred to as "concrete" for short, is usually prepared by mixing cement as a cementing material, sand and stone as aggregates, and water in a certain proportion, and stirring. The concrete has the characteristics of rich raw materials, low price and simple production process, has wide application range, is used in various civil engineering, namely shipbuilding industry, mechanical industry, ocean development, geothermal engineering and the like, and is also an important material.

Due to the characteristics of the concrete material, leakage phenomena often occur in the using process, particularly in underground and underwater structural engineering, which seriously influences and restricts the application of the concrete material. Meanwhile, the concrete has low bending strength and high brittleness, and cracks and even breaks are easily generated in use, so that the service life and safety of a building are seriously influenced, and along with the improvement of safety consciousness of people and the increase of special requirements of modern building engineering, the concrete also has more updated requirements on high strength, high fluidity, high durability, high impermeability and the like.

The addition of additives to concrete materials to improve and improve the strength, fluidity, durability and impermeability of the concrete materials is an effective measure for improving the related properties of the concrete materials. The prior art has single function of the additives, and the concrete with excellent comprehensive performance can be obtained by simultaneously adding a large amount of the additives with different weights, however, the addition of the large amount of the additives can cause negative effects on the setting time and the early and late strength of the concrete to different degrees due to the caking property problem. In addition, the additive in the prior art has the defects of poor water reducing effect, large mixing amount, poor plasticizing effect and easy deterioration. In addition, the concrete additive has limited capability of improving the related performance of concrete, and some additives contain toxic and harmful substances, pollute the environment and cause serious harm to physical and psychological health of people.

Therefore, the development of the environment-friendly concrete additive has wide market value and application prospect.

Disclosure of Invention

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.

The embodiment of the invention provides an environment-friendly concrete additive, aiming at solving the problem of poor effect of the existing concrete additive.

The embodiment of the invention is realized in such a way that the environment-friendly concrete additive comprises the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder;

the preparation method of the modified wollastonite powder comprises the following steps: dispersing wollastonite powder in ethanol, adding silane coupling agent KH55, stirring at 40-60 deg.C for reaction for 3-5 hr, centrifuging, and oven drying at 70-80 deg.C for 15-18 hr to obtain modified wollastonite powder.

As a further scheme of the invention: the mass ratio of the wollastonite powder to the ethanol to the silane coupling agent KH55 is 5 (8-12) to 0.01-0.03.

As a further scheme of the invention: the preparation method of the modified phosphogypsum comprises the following steps: mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1: (1-1.5) preparing a modifier, adding the modifier into water, and mixing to obtain a mixed solution; and uniformly spraying the mixed solution into the phosphogypsum, carrying out aging reaction for 20 hours, and drying to obtain the modified phosphogypsum.

As a further scheme of the invention: the weight ratio of the phosphogypsum to the modifier to the water is 10: (0.8-1.3): (1.5-3.5).

As a further scheme of the invention: the feed comprises the following raw materials in parts by weight: 12-17 parts of pyrophosphoric acid type titanate coupling agent, 4-6 parts of activated carbon, 27-34 parts of polyamide fiber, 12-19 parts of modified phosphogypsum and 11-18 parts of modified wollastonite powder.

As a further scheme of the invention: the feed comprises the following raw materials in parts by weight: 13-15 parts of pyrophosphoric acid type titanate coupling agent, 4-5 parts of activated carbon, 29-32 parts of polyamide fiber, 14-16 parts of modified phosphogypsum and 14-16 parts of modified wollastonite powder.

As a further scheme of the invention: the feed comprises the following raw materials in parts by weight: 13 parts of pyrophosphoric acid type titanate coupling agent, 5 parts of activated carbon, 31 parts of polyamide fiber, 16 parts of modified phosphogypsum and 14 parts of modified wollastonite powder.

An environment-friendly concrete additive and a preparation method thereof, comprising the following steps:

1) dispersing wollastonite powder in ethanol, adding a silane coupling agent KH55, stirring at 40-60 deg.C for reaction for 3-5 hr, centrifuging, and oven drying at 70-80 deg.C for 15-18 hr to obtain modified wollastonite powder; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1: 1-1.5, adding the modifier into water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use;

2) taking the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder;

3) uniformly stirring and mixing pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder in proportion, drying, adding into a ball mill, grinding for 15-25 minutes, and discharging;

4) adding polyamide fiber according to the amount, mixing uniformly, and bagging.

As a further scheme of the invention: in the step 3), the pyrophosphoric acid type titanate coupling agent, the activated carbon, the polyamide fiber, the modified phosphogypsum and the modified wollastonite powder are stirred for 3-5 hours at the temperature of 40-55 ℃ according to the proportion.

The mechanism of the invention is as follows: the adopted pyrophosphoric acid type titanate coupling agent can fill micro-gaps on the concrete interface, can enhance the bonding force between the interfaces and absorb the hydrothermal reaction in the process of forming part of concrete; the adopted activated carbon can neutralize the generation of KO2 and NaO2, activate the activity of cement, fly ash and aggregate, and enhance the affinity among the cement, fly ash and aggregate, so that the activated carbon can be well combined in the stirring process, the cement is ensured not to be separated from the aggregate in the construction and vibration process, and the self-sealing property of the concrete is improved; the modified phosphogypsum and the modified wollastonite powder are adopted, so that the activity of concrete can be further enhanced, the self-sealing property and the self-filling property of the concrete are improved, capillary pores are generated due to internal gas when the concrete is formed, and the later-stage carbonization resistance of the concrete is improved; the adopted polyamide fiber strengthens and limits the generation of cracks of concrete caused by various stresses, forms a complete soft structure net structure system in the integrally formed concrete, and transfers the hydration heat out through the fiber, thereby improving the temperature difference change resistance of the concrete caused by climate temperature change; meanwhile, the phosphogypsum is used, so that on one hand, the harmless utilization of the phosphogypsum is realized, the problem of environmental pollution is solved, on the other hand, resources are saved, wastes are changed into valuables, the production cost is reduced, and good economic and social benefits are achieved; the modification of the wollastonite powder can improve the water reducing efficiency and the fluidity of the concrete, reduce the slump loss and the surface shrinkage and cracks, improve the impermeability and the durability of the concrete and comprehensively improve the comprehensive performance of the concrete.

According to the environment-friendly concrete additive provided by the embodiment of the invention, through adding the pyrophosphoric acid type titanate coupling agent, the activated carbon, the polyamide fiber, the modified phosphogypsum and the modified wollastonite powder, the mutual synergistic effect of the components is utilized, the compressive strength, the impermeability grade, the wear resistance and the water permeability of concrete are greatly enhanced, the bonding performance among aggregates in the pervious concrete can be obviously improved, the concrete segregation and bleeding are reduced, the strength and the wear resistance of the pervious concrete are obviously improved on the basis of ensuring the water permeability, and the construction quality of engineering is ensured; meanwhile, the use realizes the harmless utilization of the phosphogypsum, solves the problem of environmental pollution, saves resources, changes waste into valuable, reduces the production cost and has good economic and social benefits.

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.

The technical effects of the environmentally friendly concrete additive of the present invention will be further described with reference to the following specific examples, but the specific implementation methods mentioned in these examples are only illustrative and explanatory of the technical solution of the present invention, and do not limit the implementation scope of the present invention, and all modifications and substitutions based on the above principles should be within the protection scope of the present invention.

Example 1

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting at 40 ℃ for 5 hours, centrifuging, and drying in a vacuum drying oven at 80 ℃ for 15 hours to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder; stirring 5 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 40 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 25 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 2

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting at 60 ℃ for 3 hours, centrifuging, and drying in a vacuum drying oven at 70 ℃ for 18 hours to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 10-18 parts of pyrophosphoric acid type titanate coupling agent, 3-6 parts of activated carbon, 25-35 parts of polyamide fiber, 10-20 parts of modified phosphogypsum and 10-20 parts of modified wollastonite powder; stirring 3 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 55 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 15 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 3

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 12-17 parts of pyrophosphoric acid type titanate coupling agent, 4-6 parts of activated carbon, 27-34 parts of polyamide fiber, 12-19 parts of modified phosphogypsum and 11-18 parts of modified wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 4

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 12-17 parts of pyrophosphoric acid type titanate coupling agent, 4-6 parts of activated carbon, 27-34 parts of polyamide fiber, 12-19 parts of modified phosphogypsum and 11-18 parts of modified wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 5

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 13-15 parts of pyrophosphoric acid type titanate coupling agent, 4-5 parts of activated carbon, 29-32 parts of polyamide fiber, 14-16 parts of modified phosphogypsum and 14-16 parts of modified wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 6

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 13-15 parts of pyrophosphoric acid type titanate coupling agent, 4-5 parts of activated carbon, 29-32 parts of polyamide fiber, 14-16 parts of modified phosphogypsum and 14-16 parts of modified wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Example 7

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 13 parts of pyrophosphoric acid type titanate coupling agent, 5 parts of activated carbon, 31 parts of polyamide fiber, 16 parts of modified phosphogypsum and 14 parts of modified wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Comparative example 1

Taking wollastonite powder, ethanol and a silane coupling agent KH55 according to the mass ratio of 5:10:0.02, dispersing the wollastonite powder in the ethanol, adding the silane coupling agent KH55, stirring and reacting for 4 hours at 50 ℃, centrifuging, and drying for 17 hours at 70 ℃ in a vacuum drying oven to obtain modified wollastonite powder for later use; mixing aluminum sulfate and magnesium aluminum silicate according to the weight ratio of 1:1, preparing a modifier, taking the phosphogypsum, the modifier and water according to the mass ratio of 10:1:3, adding the modifier into the water, and mixing to obtain a mixed solution; uniformly spraying the mixed solution into phosphogypsum, ageing and reacting for 20 hours, and drying to obtain modified phosphogypsum for later use; taking the following raw materials in parts by weight: 5 parts of activated carbon, 31 parts of polyamide fiber, 16 parts of modified phosphogypsum and 14 parts of modified wollastonite powder; stirring activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ for 4 till being uniformly mixed, then drying, adding into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Comparative example 2

Taking the following raw materials in parts by weight: 13 parts of pyrophosphoric acid type titanate coupling agent, 5 parts of activated carbon, 31 parts of polyamide fiber, 16 parts of phosphogypsum and 14 parts of wollastonite powder; stirring 4 parts of pyrophosphoric acid type titanate coupling agent, activated carbon, polyamide fiber, modified phosphogypsum and modified wollastonite powder according to a proportion at 50 ℃ until the components are uniformly mixed, then drying, adding the mixture into a ball mill for grinding for 20 minutes, and then discharging; adding polyamide fiber according to the amount, mixing uniformly, and bagging.

Comparative example 3

Conventional concrete additives are commercially available.

Experimental example 1

The concrete additives of examples 1-7 and comparative examples 1-3 were added to concrete and tested, the test results are shown in table 1, the water permeability coefficient, and the grinding pit length performance test method: refer to CJJ/T135-2009 technical Specification for pervious cement concrete pavements. Other performance testing methods were performed with reference to JG/T223-2007, with an additive addition ratio of 0.1: 100.

TABLE 1

Compared with the comparative example 3, the additive prepared in the embodiments 1 to 7 of the invention is added into the concrete, so that the compressive strength, the impermeability grade, the wear resistance and the water permeability of the concrete are greatly enhanced, the bonding performance among aggregates in the pervious concrete can be obviously improved, the concrete segregation and bleeding are reduced, the strength and the wear resistance of the pervious concrete are obviously improved on the basis of ensuring the water permeability performance, the construction quality of engineering is ensured, and the effect of the embodiment 7 is optimal; compared with the comparative examples 1-2, the performance of the additive is further improved by adding the pyrophosphoric acid type titanate coupling agent and modifying the phosphogypsum and wollastonite powder, and the adopted pyrophosphoric acid type titanate coupling agent can fill micro-gaps on the interface of concrete, can enhance the bonding force between the interfaces and absorb water thermalization in part of the concrete forming process; the adopted activated carbon can neutralize the generation of KO2 and NaO2, activate the activity of cement, fly ash and aggregate, and enhance the affinity among the cement, fly ash and aggregate, so that the activated carbon can be well combined in the stirring process, the cement is ensured not to be separated from the aggregate in the construction and vibration process, and the self-sealing property of the concrete is improved; the modified phosphogypsum and the modified wollastonite powder are adopted, so that the activity of concrete can be further enhanced, the self-sealing property and the self-filling property of the concrete are improved, capillary pores are generated due to internal gas when the concrete is formed, and the later-stage carbonization resistance of the concrete is improved; the adopted polyamide fiber strengthens and limits the generation of cracks of concrete caused by various stresses, forms a complete soft structure net structure system in the integrally formed concrete, and transfers the hydration heat out through the fiber, thereby improving the temperature difference change resistance of the concrete caused by climate temperature change; meanwhile, the phosphogypsum is used, so that on one hand, the harmless utilization of the phosphogypsum is realized, the problem of environmental pollution is solved, on the other hand, resources are saved, wastes are changed into valuables, the production cost is reduced, and good economic and social benefits are achieved; the modification of the wollastonite powder can improve the water reducing efficiency and the fluidity of the concrete, reduce the slump loss and the surface shrinkage and cracks, improve the impermeability and the durability of the concrete and comprehensively improve the comprehensive performance of the concrete.

In summary, the environmentally-friendly concrete additive provided by the embodiment of the invention greatly enhances the compressive strength, impermeability grade, wear resistance and water permeability of concrete by adding the pyrophosphoric acid type titanate coupling agent, the activated carbon, the polyamide fiber, the modified phosphogypsum and the modified wollastonite powder and utilizing the mutual synergistic effect of the components, can obviously improve the adhesive property among aggregates in the pervious concrete, reduces the concrete segregation and bleeding, obviously improves the strength and wear resistance of the pervious concrete on the basis of ensuring the water permeability, and ensures the construction quality of engineering.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.