阅读说明：本技术 一种水工用抗冲耐磨混凝土外加剂 (Anti-impact wear-resistant concrete additive for hydraulic engineering ) 是由 苏富赟 白永昇 蔺周 于 2020-12-17 设计创作，主要内容包括：本发明公开了一种水工用抗冲耐磨混凝土外加剂,涉及建筑材料领域,包括如下重量份的组分：超细硅灰300～700份,无机高弹模量纤维50～150份,硅酸锂100～300份,氟硅酸镁100～300份,三乙醇胺1～10份,木质纤维5～30份,天然无机纳米材料50～150份,纳米级二氧化硅10～50份。本发明所提供的水工用抗冲耐磨混凝土外加剂,能与水泥水化后的产物进行二次反应,生成不溶性结晶体,堵塞孔隙及裂缝,使水泥石更加密实,同时在遭受破坏时,未反应完的此纳米材料还能继续和水化产物反应,在破坏初期即进行了修复,从而达到阻止水泥基材料的进一步破坏,同时延长了建(构)物的使用寿命。(The invention discloses an impact-resistant and wear-resistant concrete admixture for hydraulic engineering, which relates to the field of building materials and comprises the following components in parts by weight: 300-700 parts of superfine silica fume, 50-150 parts of inorganic high-elastic modulus fiber, 100-300 parts of lithium silicate, 100-300 parts of magnesium fluosilicate, 1-10 parts of triethanolamine, 5-30 parts of wood fiber, 50-150 parts of natural inorganic nano material and 10-50 parts of nano silicon dioxide. The anti-impact wear-resistant concrete additive for hydraulic engineering provided by the invention can perform secondary reaction with a product after cement hydration to generate insoluble crystals to block pores and cracks, so that cement stones are more compact, and meanwhile, when the nano material is damaged, the unreacted nano material can continue to react with the hydration product, and is repaired at the initial stage of damage, so that the further damage of a cement-based material is prevented, and the service life of a building (structure) is prolonged.)

1. The anti-impact wear-resistant concrete admixture for hydraulic engineering is characterized by comprising the following components in parts by weight: 300-700 parts of superfine silica fume, 50-150 parts of inorganic high-elastic modulus fiber, 100-300 parts of lithium silicate, 100-300 parts of magnesium fluosilicate, 1-10 parts of triethanolamine, 5-30 parts of wood fiber, 50-150 parts of natural inorganic nano material and 10-50 parts of nano silicon dioxide.

2. The impact-resistant and wear-resistant concrete admixture for hydraulic engineering according to claim 1, which is characterized by comprising the following components in parts by weight: 380 parts of superfine silica fume, 50 parts of inorganic high-elastic modulus fiber, 100 parts of lithium silicate, 100 parts of magnesium fluosilicate, 5 parts of triethanolamine, 5 parts of wood fiber, 50 parts of natural inorganic nano material and 10 parts of nano-silicon dioxide.

3. The impact-resistant and wear-resistant concrete admixture for hydraulic engineering according to claim 1, which is characterized by comprising the following components in parts by weight: 310 parts of superfine silica fume, 150 parts of inorganic high-elastic modulus fiber, 200 parts of lithium silicate, 200 parts of magnesium fluosilicate, 10 parts of triethanolamine, 30 parts of wood fiber, 50 parts of natural inorganic nano material and 50 parts of nano silicon dioxide.

4. The impact-resistant and wear-resistant concrete admixture for hydraulic engineering according to claim 1, which is characterized by comprising the following components in parts by weight: 500 parts of superfine silica fume, 75 parts of inorganic high-elastic modulus fiber, 150 parts of lithium silicate, 150 parts of magnesium fluosilicate, 5 parts of triethanolamine, 30 parts of wood fiber, 60 parts of natural inorganic nano material and 30 parts of nano silicon dioxide.

5. The admixture for impact and abrasion resistant concrete for hydraulic engineering according to any one of claims 1 to 4, wherein the activity index of the ultrafine silica fume is not less than S105.

6. The impact-resistant and wear-resistant concrete admixture for hydraulic engineering according to any one of claims 1 to 4, wherein the inorganic high-elastic modulus fiber is basalt fiber.

7. The admixture for impact and wear resistant concrete for hydraulic engineering according to any one of claims 1 to 4, wherein the natural inorganic nano material is a natural hydrous lamellar chain magnesium silicate.

Technical Field

The invention relates to the technical field of building materials, in particular to an impact-resistant and wear-resistant concrete admixture for hydraulic engineering.

Background

At present, the problem of selecting high-speed water flow facing materials is often faced in water conservancy and hydropower engineering and bridge engineering. As rivers in China contain a large amount of bed load and suspension load such as silt, broken stones and the like, the bed load with high speed and sand can generate scouring damage to hydraulic concrete under the action of high-speed water flow migration. The abrasion degree of the suspension mass to hydraulic concrete is gradually increased along with the movement of water flow, various vortex flows are formed on the overflowing surface due to the non-uniformity of the concrete, the strength of the vortex flows is increased along with the increase of the flow speed, and then cavitation damage occurs.

At present, most dam outlet buildings in operation in China have different degrees of abrasion damage problems, some are even serious, and great loss is caused to the development of the economic society. With the development of water conservancy and hydropower industry, a hydraulic structure with a high water head and a large flow rate is a necessary trend, and the corrosion of the hydraulic structure is more and more prominent, which becomes a troublesome problem in the design, construction, operation and management processes of the hydraulic structure. At present, no measures for solving the problems of impact resistance and wear resistance of concrete exist, and the impact resistance and wear resistance are improved mostly by improving the compression strength grade of the concrete. Although increasing the compressive strength grade increases the abrasion resistance of the concrete, the effect is not significant. Because the directions of the anti-abrasion acting force and the anti-compression acting force are different, one is vertical to the concrete surface, and the other is parallel to the concrete surface. Therefore, for the hydraulic and hydroelectric engineering buildings, how to obviously improve the impact resistance and the wear resistance of concrete under the action of high-speed water flow is very important.

In order to improve the performance of hydraulic concrete, increase the anti-cracking, anti-impact and wear-resistant performance of concrete and prolong the service life of concrete, building material research departments in various countries in the world mostly adopt a method of doping different blends into common concrete for modification, but the addition of the blends leads harmful ions such as chloride or sulfate and the like to be introduced into the concrete, so that the corrosion effect on reinforcing steel bars is increased, and on the other hand, the shrinkage of the concrete is also adversely affected.

Disclosure of Invention

The invention aims to provide an anti-impact and wear-resistant concrete additive for hydraulic engineering, which overcomes the defects existing in the prior art of anti-impact and wear-resistant concrete for hydraulic engineering, so that the hydraulic concrete has the properties of impact resistance, wear resistance, cracking resistance, water resistance, seepage resistance, high fatigue resistance and the like, and the anti-impact and wear-resistant strength of the concrete is improved, so that the concrete performance can be improved by adding the anti-impact and wear-resistant concrete additive into the concrete with low strength grade, and the anti-impact and wear-resistant performance of the concrete with high strength grade can be even exceeded. Meanwhile, the high-strength concrete is usually higher than the low-strength concrete in terms of raw material cost, raw material selection and construction cost, so that the concrete added with the anti-impact wear-resistant concrete admixture not only improves the performance, but also reduces the comprehensive engineering cost.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

an impact-resistant and wear-resistant concrete admixture for hydraulic engineering comprises the following components in parts by weight: 300-700 parts of superfine silica fume, 50-150 parts of inorganic high-elastic modulus fiber, 100-300 parts of lithium silicate, 100-300 parts of magnesium fluosilicate, 1-10 parts of triethanolamine, 5-30 parts of wood fiber, 50-150 parts of natural inorganic nano material and 10-50 parts of nano silicon dioxide.

Preferably, the anti-impact wear-resistant concrete admixture for hydraulic engineering consists of the following components in parts by weight: 380 parts of superfine silica fume, 50 parts of inorganic high-elastic modulus fiber, 100 parts of lithium silicate, 100 parts of magnesium fluosilicate, 5 parts of triethanolamine, 5 parts of wood fiber, 50 parts of natural inorganic nano material and 10 parts of nano-silicon dioxide.

Preferably, the anti-impact wear-resistant concrete admixture for hydraulic engineering consists of the following components in parts by weight: 310 parts of superfine silica fume, 150 parts of inorganic high-elastic modulus fiber, 200 parts of lithium silicate, 200 parts of magnesium fluosilicate, 10 parts of triethanolamine, 30 parts of wood fiber, 50 parts of natural inorganic nano material and 50 parts of nano silicon dioxide.

Preferably, the anti-impact wear-resistant concrete admixture for hydraulic engineering consists of the following components in parts by weight: 500 parts of superfine silica fume, 75 parts of inorganic high-elastic modulus fiber, 150 parts of lithium silicate, 150 parts of magnesium fluosilicate, 5 parts of triethanolamine, 30 parts of wood fiber, 60 parts of natural inorganic nano material and 30 parts of nano silicon dioxide.

Preferably, the activity index of the ultrafine silica fume is not less than S105.

Preferably, the inorganic high elastic modulus fiber is basalt fiber.

Preferably, the natural inorganic nanomaterial is a natural hydrous lamellar chain magnesium silicate.

The preparation method of the hydraulic anti-impact wear-resistant concrete admixture is simple, and the materials in the formula are accurately weighed according to the proportion, uniformly mixed by a stirrer, weighed and packaged.

Compared with the prior art, the invention has the following beneficial effects:

1. the anti-impact wear-resistant concrete admixture for hydraulic engineering provided by the invention has no adverse effect on various shrinkages of hydraulic concrete;

2. the anti-impact wear-resistant concrete admixture for hydraulic engineering provided by the invention has lower contents of chloride and sulfate and has no corrosion effect on reinforcing steel bars;

3. the anti-impact wear-resistant concrete admixture for hydraulic engineering provided by the invention can effectively reduce the strength grade of concrete while improving the anti-impact wear-resistant performance of the concrete, and can select the concrete with low compressive strength grade and added with the anti-impact wear-resistant concrete admixture to replace the concrete with high compressive strength grade, thereby reducing the comprehensive engineering cost;

4. the anti-impact and wear-resistant concrete additive for hydraulic engineering provided by the invention is added with the inorganic fiber material, so that the performance of the anti-impact and wear-resistant concrete for hydraulic engineering is improved, and meanwhile, the anti-impact and wear-resistant concrete additive has the performances of water resistance, seepage prevention, corrosion prevention, high fatigue resistance and the like;

5. according to the anti-impact wear-resistant concrete admixture for hydraulic engineering, the natural inorganic nano material has good microstructure characteristics, the scanning electron microscope shows that the natural inorganic nano material is in a chain shape, the microstructure of a cement-based material interface can be effectively changed, the compactness and durability of the cement-based material are improved, the material has good cohesiveness and adsorptivity, the surface tension of water on the concrete interface can be reduced, and meanwhile, the anti-impact wear-resistant concrete admixture for hydraulic engineering has very good water retention performance, so that the concrete performance is improved;

6. the anti-impact wear-resistant concrete additive for hydraulic engineering provided by the invention can perform secondary reaction with a product after cement hydration to generate insoluble crystals to block pores and cracks, so that cement stones are more compact, meanwhile, when the nano material is damaged, the unreacted nano material can continue to react with the hydration product, and the nano material is repaired at the initial stage of damage, thereby preventing the further damage of a cement-based material and prolonging the service life of a building (structure);

7. the hydraulic impact-resistant and wear-resistant concrete admixture further improves the performance of cement-based materials, and can be filled in gaps of cement stone materials and further react with hydration products to improve the compactness of cement by adding ultrafine powder due to small particle size and activity, so that the durability and mechanical properties of the cement stone are improved.

Drawings

FIG. 1 is a TEM topography of natural inorganic nanomaterials;

FIG. 2 is an SEM topography of pure quicklime;

FIG. 3 is an SEM topography of the reaction of natural inorganic nanomaterials with alkali;

FIG. 4 is an SEM topography of the hydration reaction of the impact-resistant concrete admixture and the cement provided in example 1;

FIG. 5 is an SEM topography of the hydration reaction of the impact-resistant concrete admixture and the cement provided in example 2;

FIG. 6 is an SEM topography of an impact-resistant concrete admixture improved concrete interface provided in example 1;

FIG. 7 is an SEM topography of an improved concrete interface of the impact-resistant concrete admixture provided in example 2;

FIG. 8 is an SEM (scanning electron microscope) morphology of internal microcracks of ordinary concrete after an underwater steel ball method test;

FIG. 9 is an SEM (scanning electron microscope) morphology of internal microcracks of the impact-resistant and wear-resistant concrete after an underwater steel ball method test by adding the impact-resistant and wear-resistant concrete admixture.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the present invention is further described below with reference to various embodiments, and the implementation manner of the present invention includes but is not limited to the following embodiments.

Example 1

In the embodiment, the anti-impact wear-resistant concrete admixture for hydraulic engineering comprises the following components in parts by weight:

ultra-fine silica fume: 680 parts of inorganic high-elastic modulus fiber: 50 parts, lithium silicate: 100 parts of magnesium fluosilicate: 100 parts of triethanolamine: 5 parts, wood fiber: 5 parts of natural inorganic nano material: 50 parts, nano-scale silica: 10 parts.

The formula materials are accurately weighed according to the proportion, uniformly mixed by a stirrer, weighed and packaged.

Example 2

In the embodiment, the anti-impact wear-resistant concrete admixture for hydraulic engineering comprises the following components in parts by weight:

ultra-fine silica fume: 310 parts of inorganic high-elastic modulus fiber: 150 parts, lithium silicate: 200 parts of magnesium fluosilicate: 200 parts, triethanolamine: 10 parts, wood fiber: 30 parts of natural inorganic nano material: 50 parts, nano-scale silica: 50 parts of the raw materials.

The formula materials are accurately weighed according to the proportion, uniformly mixed by a stirrer, weighed and packaged.

Example 3

In the embodiment, the anti-impact wear-resistant concrete admixture for hydraulic engineering comprises the following components in parts by weight:

ultra-fine silica fume: 500 parts of inorganic high-elastic modulus fiber: 75 parts, lithium silicate: 150 parts, magnesium fluosilicate: 150 parts, triethanolamine: 5 parts, wood fiber: 30 parts of natural inorganic nano material: 60 parts, nano-scale silica: 30 parts of.

The formula materials are accurately weighed according to the proportion, uniformly mixed by a stirrer, weighed and packaged.

In examples 1 to 3, the natural inorganic nano-material is a natural non-metal clay mineral, specifically, a hydrous lamellar chain magnesium silicate, which has a unique lamellar chain structure characteristic, has characteristics of large specific surface area, strong water retention capacity, good chemical stability, strong adsorption capacity, and the like, and the monomer thereof is in a nano size.

Comparative experiment

The admixtures obtained in examples 1 to 3 were mixed in an amount of 10kg/m³The test data (shown in table 1) show that, when the admixture provided by the invention is added, the cumulative mass loss, wear rate and shrinkage ratio of the test piece of the C45 concrete are all less than those of the C45 concrete and the C60 concrete with higher strength, and the impact abrasion strength is higher than that of the C45 concrete and the C60 concrete with higher strength.

Table 1 concrete test data

The difference of each component is seen from an electron microscope scanning image:

as shown in fig. 1, the TEM morphology of natural inorganic nano material is fibrous, the growth preferentially develops in one-dimensional direction, the direction of chain structure is consistent with the axial direction of fiber, the length is about 500nm, and the diameter is about 20 nm;

fig. 2 is an SEM topography of pure quicklime, and fig. 3 is an SEM topography of a reaction of natural inorganic nanomaterial with alkali. As can be seen from fig. 2, calcium hydroxide grew well and had a smooth surface. As can be seen from FIG. 3, the natural inorganic nano-material reacts with calcium hydroxide, and the surface is rough and uneven. Thereby proving that the natural inorganic nano material in the macro can promote the hydration of the cement and improve the performance of the cement;

FIG. 4 and FIG. 5 show the nucleation of the hydration reaction of the anti-impact wear-resistant concrete admixture and the cement. As can be seen from the figure, the addition of the natural inorganic nano-materials further enhances the interface improvement effect of each level in the concrete. In fresh concrete, irregular brownian motion acts like a crystal nucleus, and the hydration time is prolonged and the size of the hydration product is increased.

FIG. 6 and FIG. 7 are SEM images of the appearance of the impact-resistant and wear-resistant concrete admixture in improving the concrete interface. As can be seen from FIGS. 6 and 7, the formation of nucleation makes the weak interface environment have a space for the growth of the hydration product, increases the growth nodes of the hydration product, reduces the thickness of the water pocket at the bottom of the aggregate, and reduces the width of the interface transition zone of thick and thin aggregates.

FIG. 8 shows internal microcracks of ordinary concrete after underwater steel ball test. FIG. 9 shows the internal microcracks of the impact-resistant and wear-resistant concrete after the underwater steel ball method test with the addition of the impact-resistant and wear-resistant concrete admixture. From the figure, we can figure out that the improvement of the impact and abrasion resistance of the concrete is macroscopically represented by the increase of the impact and abrasion resistance strength of the concrete and the reduction of the internal interface damage caused by the bad acting force.

The above-mentioned embodiment is only one of the preferred embodiments of the present invention, and should not be used to limit the scope of the present invention, but all the insubstantial modifications or changes made within the spirit and scope of the main design of the present invention, which still solve the technical problems consistent with the present invention, should be included in the scope of the present invention.