CN116573894B

CN116573894B - Granite concrete and preparation method thereof

Info

Publication number: CN116573894B
Application number: CN202310608448.0A
Authority: CN
Inventors: 高国成; 周超; 蔡晓峰
Original assignee: Weihai Wanjiayuan New Building Materials Co ltd
Current assignee: Weihai Wanjiayuan New Building Materials Co ltd
Priority date: 2023-05-27
Filing date: 2023-05-27
Publication date: 2024-06-07
Anticipated expiration: 2043-05-27
Also published as: CN116573894A

Abstract

The application relates to the field of energy-saving building materials, and particularly discloses granite concrete and a preparation method thereof; the granite concrete is prepared from the following raw materials in parts by weight: 160-190 parts of cement, 155-190 parts of granite fine powder, 900-950 parts of carrier granite stone chips, 900-1050 parts of modified granite broken stone, 155-180 parts of water, 6-8.5 parts of water reducer and 0.2-1 part of air entraining agent; the modified granite gravels are prepared from granite gravels loaded with polyacrylamide particles, rigid fibers and flexible fibers; the preparation method comprises the following steps: mixing the modified granite gravels and cement uniformly, adding the carrier granite gravels and the granite fine powder, mixing uniformly, adding water, a water reducing agent and an air entraining agent, and mixing uniformly to prepare a mixture; pouring, vibrating and curing the mixture to obtain a finished product; the granite concrete has the advantages of higher mechanical strength and better durability.

Description

Granite concrete and preparation method thereof

Technical Field

The application relates to the field of energy-saving building materials, in particular to granite concrete and a preparation method thereof.

Background

Along with the continuous development of the building field, the demand of building materials is increased increasingly, so that the demand of broken stone, river sand, fly ash and mineral powder in concrete is increased gradually; however, the resources of natural sand and natural crushed stone are gradually depleted, and due to the rapid development of hydroelectric construction, the supply and shortage of fly ash and mineral powder are also caused, so that it is imperative to find a substitute which is easy to obtain and can ensure the quality of the building.

Granite belongs to an invading rock in acid magma rock, is a common rock and is relatively easy to obtain; and the granite has higher strength and lower water absorption, and can ensure the strength and the service life of the building after being applied to the field of building.

However, granite has high hardness and density, is difficult to be fully mixed with cement and other substances, and is easy to generate cracks and hollows, so that the strength and durability of concrete are affected.

Therefore, how to prepare granite concrete which is not easy to crack and void and has high mechanical strength and good durability is a problem to be solved.

Disclosure of Invention

In order to prepare granite concrete which is not easy to crack and bulge and has higher mechanical strength and better durability, the application provides granite concrete and a preparation method thereof.

In a first aspect, the application provides granite concrete, which adopts the following technical scheme:

The granite concrete is prepared from the following raw materials in parts by weight: 160-190 parts of cement, 155-190 parts of granite fine powder, 900-950 parts of carrier granite stone chips, 900-1050 parts of modified granite broken stone, 155-180 parts of water, 6-8.5 parts of water reducer and 0.2-1 part of air entraining agent; the modified granite broken stone is prepared by sequentially loading polyacrylamide particles, rigid fibers and flexible fibers on the granite broken stone with the mass ratio of 100:1-8:0.5-1:0.8-1.4.

Through adopting above-mentioned technical scheme, granite rubble, polyacrylamide granule, rigid fiber and flexible fiber cooperate, and the granite rubble surface is loaded the polyacrylamide granule earlier, then loads the rigid fiber, uses polyacrylamide granule and rigid fiber as braced frame, uses flexible fiber as winding network, makes the granite rubble surface form the network structure of interweaving, after mixing with the cement granule, utilizes the network structure on granite rubble surface, is convenient for a part of small-size cement granule get into the granite rubble.

In the process of preparing the mixture, the lightweight flexible fiber and the network structure are convenient for the granite gravels to be in uniform contact with cement particles, so that the granite gravels are uniformly dispersed in the mixture, and the problems of sedimentation or uneven mixing with cement are difficult to occur due to high self density and smooth surface.

In the hydration process, cement particles entering the network structure are convenient for reacting with minerals such as quartz, feldspar and the like in granite to generate calcium silicate gel and other hydration products, and space pores of the network structure can provide space for expansion of the hydration products, so that the expansion is avoided as much as possible to increase internal stress of the concrete, and structural cracks in the concrete are reduced; in the mixing and hydration processes, the polyacrylamide is gradually dissolved in water, and is matched with vibration, so that polyacrylamide particles are conveniently separated from the surface of granite broken stone, an expansion space is further provided for hydration products on the surface of the granite broken stone, and the polyacrylamide particles separated from the granite broken stone utilize the advantage of light weight, and can gradually move towards the upper surface of poured concrete in the vibration process, so that the expansion stress is further prevented from influencing the internal structure of the concrete to generate cracks; along with the progress of hydration reaction, water and gas gradually flow out from the upper part of the concrete, and polyacrylamide particles can fill structural pores of the concrete close to the upper surface after the concrete is solidified, so that the structural density of the concrete is improved, and the mechanical strength of the concrete is improved; meanwhile, in the drying shrinkage process, the problems of structural cracks and hollowness in the concrete can be further prevented by utilizing the elastic buffer effect of the flexible fibers; the granite concrete has the advantages of being difficult to crack and empty, high in mechanical strength and high in durability.

Preferably, the granite stone chips in the carrier granite stone chips consist of stone chips with the particle size of 20-75 mu m and stone chips with the particle size of 80-400 mu m in a mass ratio of 1:5-9.

By adopting the technical scheme, the stone chips with different particle sizes are limited, so that the stone chips can be uniformly dispersed, the density of the internal structure of the concrete is improved, and the mechanical strength of the concrete is improved.

Preferably, the granite broken stone comprises the following raw materials in parts by weight: 160-200 parts of crushed stone with the grain size of 0.5-1cm, 580-650 parts of crushed stone with the grain size of 1-2cm and 160-200 parts of crushed stone with the grain size of 2-3 cm.

Through adopting above-mentioned technical scheme, inject the rubble of different particle diameters and different proportions, improve structural density when being convenient for rubble evenly dispersed, utilize the higher intensity of rubble, can further improve the mechanical strength of concrete.

Preferably, the cement consists of cement particles with the particle size of 10-60 mu m and cement particles with the particle size of 80-200 mu m in a mass ratio of 1:3-5.

By adopting the technical scheme, the small-particle cement with the particle size of 10-40 mu m can conveniently enter the pores of the network structure on the surface of the granite broken stone, and mineral substances in the granite can conveniently react with the small-particle cement close to the granite in the network structure, so that the stable dispersion of the granite broken stone is realized, the bonding effect of the granite broken stone and the cement gel material can be improved after hydration, the compactness of the internal structure of the concrete is improved, cracks and hollows are not easy to generate in the concrete, and the concrete has higher mechanical strength.

Preferably, the polyacrylamide particles are prepared by mixing low-viscosity polyacrylamide aqueous solution and nano filler in a mass ratio of 10:5-8, freeze-drying and crushing.

By adopting the technical scheme, the low-viscosity polyacrylamide aqueous solution and the nano filler are matched, so that the nano filler is dispersed and bonded in the low-viscosity polyacrylamide aqueous solution, and the nano filler is matched with freeze drying, so that the nano filler is dispersed and bonded in the polyacrylamide particles, and the polyacrylamide is gradually dissolved in the mixing and vibrating process, so that the polyacrylamide particles are gradually separated from the granite broken stone surface, and the nano particles are conveniently positioned above the concrete by utilizing the characteristic of light weight of the nano particles, thereby being convenient for filling pores generated by water loss and gas loss in the hydration process, and improving the mechanical strength of the concrete; with the gradual rise of the hydration temperature, the low-viscosity polyacrylamide is further promoted to be completely dissolved, the low-viscosity polyacrylamide flows after being dissolved in water, and after the hydration is finished, the polyacrylamide can further fill the pores in the concrete, so that the mechanical strength of the concrete is further improved.

Preferably, the nano filler consists of nano silicon nitride and hollow glass beads in a mass ratio of 1:1-3.

Through adopting above-mentioned technical scheme, nanometer silicon nitride, hollow glass bead cooperate, and nanometer silicon nitride density is greater than hollow glass bead, and hollow glass bead is located concrete top more easily, and nanometer silicon nitride is located hollow glass bead below aperture position department easily, realizes the packing of different degrees to the inside structure hole of concrete to improve the structure density of concrete, make the concrete have higher mechanical strength.

Preferably, the rigid fiber is prepared from polypropylene fiber, ethylcellulose solution and phosphatidylserine in a mass ratio of 1:0.1-0.2:0.1-0.3.

By adopting the technical scheme, the polypropylene fiber, the ethyl cellulose solution and the phosphatidylserine are matched, and the phosphatidylserine is conveniently bonded on the surface of the polypropylene fiber by utilizing the viscosity of the ethyl cellulose solution; the characteristics of light weight of the polypropylene fibers are utilized, so that the polypropylene fibers are convenient to be matched with the flexible fibers, granite rubble is uniformly dispersed in concrete mixture, and the sedimentation and accumulation problems are not easy to occur; and the hydrophilic group in phosphatidylserine is utilized to facilitate water to reach the surface of the rigid fiber, and the characteristics of water insolubility of phosphatidylserine are matched, and the non-hydrophilic and water insolubility of the ethyl cellulose solution are utilized to facilitate water to be transferred to the surface of the granite broken stone on the surface of the rigid fiber, so that the hydration of cement particles near the granite is promoted, the cement particles around the modified granite broken stone are hydrated, and have a larger contact area with a fiber network structure, so that the bonding effect of the granite broken stone and the cement cementing material can be further improved, and the mechanical strength of the concrete is improved.

Preferably, the flexible fiber is composed of hydrophobic aluminum silicate fiber cotton and ethyl cellulose solution in a mass ratio of 1:0.15-0.3.

By adopting the technical scheme, the hydrophobic aluminum silicate fiber cotton and the ethylcellulose solution are matched, and the characteristics of hydrophobicity of the hydrophobic aluminum silicate fiber cotton, non-hydrophilicity and water insolubility of the ethylcellulose are utilized, so that the moisture in the mixture can reach the surface of granite broken stone to contact with cement particles, the hydration reaction is ensured, and the bonding effect of the granite broken stone and the cementing material is improved; in addition, in the process of expansion of the cementing material, the hydrophobic aluminum silicate fiber cotton utilizes higher flexibility to facilitate the deformation of structural bending, provide space for expansion, and reduce the internal expansion stress of the concrete, thereby reducing the internal cracks and hollows of the concrete and enabling the concrete to have higher mechanical strength.

Preferably, the granite chips are prepared from granite chips, polyvinyl alcohol solution and agarose with low melting point in a mass ratio of 100:2-7:2-8.

Through adopting above-mentioned technical scheme, granite stone bits, polyvinyl alcohol solution, low-melting agarose cooperate, utilize the viscidity of polyvinyl alcohol, be convenient for low-melting agarose bonds on granite stone bits surface, in the hydration, utilize the hydrophilicity of hydroxyl in the hydrophilic cooperation low-melting agarose of polyvinyl alcohol film-forming back hydroxyl, can improve the bonding effect of granite stone bits and cementing material, the rising of cooperation hydration temperature, after reaching low-melting agarose's fusing point, low-melting agarose melts gradually, utilize its viscidity to further improve the bonding effect of granite stone bits and cementing material, thereby improve concrete inner structure compactness, make the concrete have higher mechanical strength.

In a second aspect, the application provides a preparation method of granite concrete, which adopts the following technical scheme:

the preparation method of the granite concrete comprises the following steps:

s1, adding cement into modified granite gravels, uniformly mixing and stirring, adding carrier granite chips and granite fine powder, and uniformly mixing to obtain a primary mixed material;

S2, weighing water, a water reducing agent and an air entraining agent, adding the water reducing agent, the water reducing agent and the air entraining agent into the primary mixed material, and uniformly mixing and stirring to obtain a mixture;

s3, pouring, vibrating and curing the mixture to obtain a finished product.

Through adopting above-mentioned technical scheme, granite rubble mixes with cement earlier, and the small granule cement particle gets into in the network structure on granite rubble surface in the cement of being convenient for, then mixes with year material granite rubble and granite fine powder again, makes the granite evenly disperse in the concrete to be difficult for producing the phenomenon of deposit, after hydration, makes the difficult crack and the hollowing that produce of finished concrete, thereby makes the concrete have higher mechanical strength.

In summary, the application has the following beneficial effects:

1. The granite broken stone, the polyacrylamide particles, the rigid fibers and the flexible fibers are matched, the polyacrylamide particles are loaded on the surface of the granite broken stone, then the rigid fibers are loaded, the polyacrylamide particles and the rigid fibers are used as supporting frameworks, the flexible fibers are used as winding networks, an interweaved network structure is formed on the surface of the granite broken stone, the bonding effect of the granite broken stone and the cementing material is improved, the gaps of the internal structure of the concrete can be filled with the polyacrylamide particles, and the mechanical strength of the concrete is improved.

2. In the pouring vibration and hydration process, moisture gradually reaches the granite stone surface through flexible fibers and rigid fibers and contacts with polyacrylamide particles, the water-soluble effect of the polyacrylamide particles is utilized, so that the polyacrylamide water-soluble carrying nano filler is convenient to separate from the granite stone surface, an expansion space is provided for hydration of cement close to the granite stone surface, the flexible change of the flexible fibers and the pores of a fiber network structure are matched, an expansion space is further provided for hydration of the cement, the expansion stress is reduced, the concrete is not easy to crack and hollowing, and in the drying shrinkage process, the crack is avoided as much as possible by utilizing the strength and flexibility of the fibers; meanwhile, due to the fact that the granite is high in density, under the action of polyacrylamide particles, good filling effects can be conveniently achieved at all positions in the concrete, and the mechanical strength of the concrete is further improved.

3. The granite chips, the polyvinyl alcohol solution and the low-melting-point agarose are matched, the viscosity of the polyvinyl alcohol is utilized, the low-melting-point agarose is convenient to bond on the surface of the granite chips, in the hydration process, the hydrophilicity of the hydroxyl groups is matched with the hydrophilicity of the hydroxyl groups in the low-melting-point agarose after the polyvinyl alcohol is used for forming a film, the bonding effect of the granite chips and the cementing material can be improved, the low-melting-point agarose is gradually melted after the melting point of the low-melting-point agarose is reached by matching with the increase of the hydration temperature, and the bonding effect of the granite chips and the cementing material is further improved by utilizing the viscosity of the low-melting-point agarose, so that the compactness of the internal structure of the concrete is improved, and the concrete has higher mechanical strength.

Detailed Description

The present application will be described in further detail with reference to examples.

Preparation example of carried granite chips

Preparation example 1: the material-carrying granite stone chips are prepared by the following method:

Uniformly spraying 5kg of polyvinyl alcohol solution on the surface of 100kg of granite stone chips, wherein the granite stone chips consist of stone chips with the particle size of 20-75 mu m and stone chips with the particle size of 80-400 mu m in a mass ratio of 1:7, the polyvinyl alcohol solution is a polyvinyl alcohol aqueous solution with the mass fraction of 5%, the molecular weight of the polyvinyl alcohol is 500 ten thousand, then uniformly spraying 6kg of low-melting-point agarose, the melting point of the low-melting-point agarose is 62-65 ℃, uniformly mixing, drying, dispersing until the granite stone chips have no agglomeration and adhesion, and obtaining the finished product of the granite stone chips with the material.

Preparation example 2: the material-carrying granite stone chips are prepared by the following method:

Uniformly spraying 2kg of polyvinyl alcohol solution on the surface of 100kg of granite stone chips, wherein the granite stone chips consist of stone chips with the particle size of 20-75 mu m and stone chips with the particle size of 80-400 mu m in a mass ratio of 1:5, the polyvinyl alcohol solution is a polyvinyl alcohol aqueous solution with the mass fraction of 5%, the molecular weight of the polyvinyl alcohol is 500 ten thousand, then uniformly spraying 2kg of low-melting-point agarose, the melting point of the low-melting-point agarose is 62-65 ℃, uniformly mixing, drying, dispersing until the granite stone chips have no agglomeration and adhesion, and obtaining the finished product of the granite stone chips with the material.

Preparation example 3: the material-carrying granite stone chips are prepared by the following method:

Uniformly spraying 7kg of polyvinyl alcohol solution on the surface of 100kg of granite stone chips, wherein the granite stone chips consist of stone chips with the particle size of 20-75 mu m and stone chips with the particle size of 80-400 mu m in a mass ratio of 1:9, the polyvinyl alcohol solution is a polyvinyl alcohol aqueous solution with the mass fraction of 5%, the molecular weight of the polyvinyl alcohol is 500 ten thousand, then uniformly spraying 8kg of low-melting-point agarose, the melting point of the low-melting-point agarose is 62-65 ℃, uniformly mixing, drying, dispersing until the granite stone chips have no agglomeration and adhesion, and obtaining the finished product of the granite stone chips with the material.

Preparation example of Polyacrylamide particles

Preparation example 4: the polyacrylamide particles are prepared by the following method:

6.5kg of nano filler is added into 10kg of low-viscosity polyacrylamide aqueous solution, the concentration of the low-viscosity polyacrylamide aqueous solution is 2%, the molecular weight of the low-viscosity polyacrylamide is 300 ten thousand, the nano filler consists of nano silicon nitride and hollow glass beads with the mass ratio of 1:2, the particle size of the nano silicon nitride is 80nm, the particle size of the hollow glass beads is 100nm, and after uniform mixing and dispersion, the polyacrylamide particles are prepared through freeze drying and crushing, and the polyacrylamide particles are sieved by a 200-mesh sieve.

Preparation example 5: the polyacrylamide particles are prepared by the following method:

5kg of nano filler is added into 10kg of low-viscosity polyacrylamide aqueous solution, the concentration of the low-viscosity polyacrylamide aqueous solution is 2%, the molecular weight of the low-viscosity polyacrylamide is 300 ten thousand, the nano filler consists of nano silicon nitride and hollow glass beads with the mass ratio of 1:1, the particle size of the nano silicon nitride is 80nm, the particle size of the hollow glass beads is 100nm, and after uniform mixing and dispersion, the polyacrylamide particles are prepared through freeze drying and crushing, and the polyacrylamide particles are sieved by a 200-mesh sieve.

Preparation example 6: the polyacrylamide particles are prepared by the following method:

8kg of nano filler is added into 10kg of low-viscosity polyacrylamide aqueous solution, the concentration of the low-viscosity polyacrylamide aqueous solution is 2%, the molecular weight of the low-viscosity polyacrylamide is 300 ten thousand, the nano filler consists of nano silicon nitride and hollow glass beads with the mass ratio of 1:3, the particle size of the nano silicon nitride is 80nm, the particle size of the hollow glass beads is 100nm, and after uniform mixing and dispersion, the polyacrylamide particles are prepared through freeze drying and crushing, and the polyacrylamide particles are sieved by a 200-mesh sieve.

Preparation of rigid fibers

Preparation example 7: the rigid fiber is prepared by the following method:

Uniformly spraying 0.16kg of ethyl cellulose solution on the surface of 1kg of polypropylene fiber, uniformly spraying 0.2kg of phosphatidylserine, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, the ethanol is absolute ethanol with the mass fraction of 99%, the length of the polypropylene fiber is 3mm, the particle size of the phosphatidylserine is 10 mu m, and after uniform mixing, drying and dispersing until the polypropylene fibers are not adhered to each other, thus obtaining the finished product.

Preparation example 8: the rigid fiber is prepared by the following method:

Uniformly spraying 0.1kg of ethyl cellulose solution on the surface of 1kg of polypropylene fiber, uniformly spraying 0.1kg of phosphatidylserine, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, the ethanol is absolute ethanol with the mass fraction of 99%, the length of the polypropylene fiber is 3mm, the particle size of the phosphatidylserine is 10 mu m, and after uniform mixing, drying and dispersing until the polypropylene fibers are not adhered to each other, thus obtaining the finished product.

Preparation example 9: the rigid fiber is prepared by the following method:

Uniformly spraying 0.2kg of ethyl cellulose solution on the surface of 1kg of polypropylene fiber, uniformly spraying 0.3kg of phosphatidylserine, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, the ethanol is absolute ethanol with the mass fraction of 99%, the length of the polypropylene fiber is 3mm, the particle size of the phosphatidylserine is 10 mu m, and after uniform mixing, drying and dispersing until the polypropylene fibers are not adhered to each other, thus obtaining the finished product.

Preparation example of Flexible fiber

Preparation example 10: the flexible fiber is prepared by the following method:

Soaking and dispersing aluminum silicate fiber cotton in a silane coupling agent KH-570, taking out the aluminum silicate fiber cotton, drying and scattering to obtain hydrophobic aluminum silicate fiber cotton, wherein the length of the hydrophobic aluminum silicate fiber cotton is 4mm;

0.2kg of ethyl cellulose solution is uniformly sprayed on the surface of 1kg of hydrophobic aluminum silicate fiber cotton, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, and the ethanol is absolute ethanol with the mass fraction of 99%, and the ethyl cellulose ethanol solution is uniformly dispersed until the fibers are not agglomerated and adhered to each other, so that the finished flexible fiber is prepared.

Preparation example 11: the present preparation example differs from preparation example 10 in that:

0.15kg of ethyl cellulose solution is uniformly sprayed on the surface of 1kg of hydrophobic aluminum silicate fiber cotton, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, and the ethanol is absolute ethanol with the mass fraction of 99%, and the ethyl cellulose ethanol solution is uniformly dispersed until the fibers are not agglomerated and adhered to each other, so that the finished flexible fiber is prepared.

Preparation example 12: the present preparation example differs from preparation example 10 in that:

0.3kg of ethyl cellulose solution is uniformly sprayed on the surface of 1kg of hydrophobic aluminum silicate fiber cotton, wherein the ethyl cellulose solution is ethyl cellulose ethanol solution with the mass fraction of 1%, and the ethanol is absolute ethanol with the mass fraction of 99%, and the ethyl cellulose ethanol solution is uniformly dispersed until the fibers are not agglomerated and adhered to each other, so that the finished flexible fiber is prepared.

Preparation example of modified granite macadam

Preparation example 13: the modified granite broken stone is prepared by the following method:

Weighing 180kg of crushed stone with the grain size of 0.5-1cm, 620kg of crushed stone with the grain size of 1-2cm and 180kg of crushed stone with the grain size of 2-3cm, and uniformly mixing and stirring to obtain granite crushed stone;

Spraying 2kg of polyacrylamide solution on the surface of 5kg of polyacrylamide particles prepared in preparation example 4, uniformly spraying the solution onto the surface of 100kg of granite broken stone, uniformly spraying 0.5kg of polyacrylamide solution, uniformly spraying 0.8kg of rigid fibers prepared in preparation example 7, uniformly spraying 1.2kg of flexible fibers prepared in preparation example 10, drying and dispersing until the granite broken stone is not agglomerated or adhered to each other, and obtaining finished modified granite broken stone; the mass fraction of the polyacrylamide solution is 1%, and the molecular weight of the polyacrylamide is 300 ten thousand.

Preparation example 14: the modified granite broken stone is prepared by the following method:

160kg of gravels with the particle size of 0.5-1cm, 580kg of gravels with the particle size of 1-2cm and 160kg of gravels with the particle size of 2-3cm are weighed, mixed and stirred uniformly to prepare granite gravels;

Spraying 0.4kg of polyacrylamide solution on the surface of 1kg of polyacrylamide particles prepared in preparation example 5, uniformly spraying the polyacrylamide solution onto the surface of 100kg of granite broken stone, uniformly spraying 0.2kg of polyacrylamide solution, uniformly spraying 0.5kg of rigid fibers prepared in preparation example 8, uniformly spraying 0.8kg of flexible fibers prepared in preparation example 11, drying, dispersing until granite broken stone is not agglomerated and adhered to each other, and preparing finished modified granite broken stone; the mass fraction of the polyacrylamide solution is 1%, and the molecular weight of the polyacrylamide is 300 ten thousand.

Preparation example 15: the modified granite broken stone is prepared by the following method:

weighing 200kg of crushed stone with the grain size of 0.5-1cm, 650kg of crushed stone with the grain size of 1-2cm and 200kg of crushed stone with the grain size of 2-3cm, and uniformly mixing and stirring to obtain granite crushed stone;

Spraying 3kg of polyacrylamide solution on the surfaces of 8kg of polyacrylamide particles prepared in preparation example 6, uniformly spraying the polyacrylamide solution onto the surfaces of 100kg of granite gravels, uniformly spraying 0.8kg of polyacrylamide solution, uniformly spraying 1kg of rigid fibers prepared in preparation example 9, uniformly spraying 1.4kg of flexible fibers prepared in preparation example 12, drying, dispersing until the granite gravels are not agglomerated and adhered to each other, and preparing finished modified granite gravels; the mass fraction of the polyacrylamide solution is 1%, and the molecular weight of the polyacrylamide is 300 ten thousand.

Examples

Example 1: granite concrete:

175kg of cement, 170kg of granite fine powder, 930kg of carried granite chips, 1000kg of modified granite gravels, 168kg of water, 7.4kg of water reducer and 0.6kg of air entraining agent; the cement consists of cement particles with the particle size of 10-60 mu m and cement particles with the particle size of 80-200 mu m in a mass ratio of 1:4, wherein the cement particles are Portland cement with the particle size of P.O42.5; the granite fine powder is sieved by a 300-mesh sieve, and the carried granite chips prepared in preparation example 1 are adopted; the modified granite broken stone prepared in preparation example 13 is adopted; the water reducer is a polycarboxylic acid high-efficiency water reducer; the air entraining agent consists of sodium abietate and triterpenoid saponin in the mass ratio of 1:1;

the preparation method comprises the following steps:

s3, pouring, vibrating and curing the mixture to obtain a finished product.

Example 2: this embodiment differs from embodiment 1 in that:

160kg of cement, 155kg of granite fine powder, 900kg of carried granite chips, 900kg of modified granite broken stone, 155kg of water, 6kg of water reducer and 0.2kg of air entraining agent; the cement consists of cement particles with the particle size of 10-60 mu m and cement particles with the particle size of 80-200 mu m in a mass ratio of 1:3, wherein the cement particles are Portland cement with the particle size of P.O42.5; the granite fine powder is sieved by a 300-mesh sieve, and the carried granite chips prepared in preparation example 2 are adopted; the modified granite broken stone prepared in preparation example 14 was used.

Example 3: this embodiment differs from embodiment 1 in that:

190kg of cement, 190kg of granite fine powder, 950kg of carried granite stone chips, 1050kg of modified granite broken stone, 180kg of water, 8.5kg of water reducer and 1kg of air entraining agent; the cement consists of cement particles with the particle size of 10-60 mu m and cement particles with the particle size of 80-200 mu m in a mass ratio of 1:5, wherein the cement particles are Portland cement with the particle size of P.O42.5; the granite fine powder is sieved by a 300-mesh sieve, and the carried granite chips prepared in preparation example 3 are adopted; the modified granite broken stone prepared in preparation example 15 was used.

Example 4: this embodiment differs from embodiment 1 in that:

The particle size of the cement is 100-200 mu m.

Example 5: this embodiment differs from embodiment 1 in that:

No nanofiller was added to the polyacrylamide particles.

Example 6: this embodiment differs from embodiment 1 in that:

The polyacrylamide particles are prepared by replacing low-viscosity polyacrylamide aqueous solution with high-viscosity polyacrylamide aqueous solution with the same mass, wherein the mass fraction of the high-viscosity polyacrylamide aqueous solution is 10%, and the molecular weight is 2000 ten thousand.

Example 7: this embodiment differs from embodiment 1 in that:

The nano filler is prepared by replacing nano silicon nitride with hollow glass beads with the same quality.

Example 8: this embodiment differs from embodiment 1 in that:

no phosphatidylserine was added to the rigid fiber.

Example 9: this embodiment differs from embodiment 1 in that:

the rigid fiber is glass fiber chopped yarn with the length of 3mm.

Example 10: this embodiment differs from embodiment 1 in that:

The flexible fiber is replaced by the aluminum silicate fiber cotton with the same quality.

Example 11: this embodiment differs from embodiment 1 in that:

no agarose with low melting point is added into the granite chips of the carrier.

Comparative example

Comparative example 1: this comparative example differs from example 1 in that:

The granite stone chips with the same mass are used for replacing the granite stone chips of the carrier, and the granite stone chips with the same mass are used for replacing the modified granite stone chips.

Comparative example 2: this embodiment differs from embodiment 1 in that:

In the preparation process of the modified granite rubble, rigid fibers and flexible fibers are not added.

Performance test

1. Mechanical strength detection

The preparation methods of examples 1-11 and comparative examples 1-2 were used to prepare finished granite concrete, and the compressive strength of 28d was measured and data recorded with reference to GB/T50081-2019, standard test method for physical mechanical Properties of concrete.

2. Crack detection

The finished granite concrete was prepared by the preparation methods of examples 1 to 11 and comparative examples 1 to 2, respectively, the test block size was length×width×height=1m× 1m× 1m, and after curing for 28d, the building was vertically divided in the length direction, and the number of internal cracks of examples 1 to 11 and comparative examples 1 to 2 and the number of hollows of examples 1 to 3 were recorded.

Table 1 performance test table

Project	Compressive Strength/MPa	Number of cracks/strip	Number of empty drums/number of empty drums
				Example 1	43.6	4	1
Example 2	42.5	6	3
				Example 3	44.0	3	1
Example 4	40.8	10	/
				Example 5	38.5	15	/
Example 6	40.4	11	/
				Example 7	42.9	6	/
Example 8	41.2	9	/
				Example 9	42.3	7	/
Example 10	37.3	18	/
				Example 11	38.9	14	/
Comparative example 1	31.5	28	/
				Comparative example 2	34.6	23	/

As can be seen by combining examples 1-3 and Table 1, the granite concrete prepared by the method has higher compressive strength, fewer cracks and fewer hollows, and the finished granite concrete has higher mechanical strength and good durability.

As can be seen from the combination of examples 1 and examples 4-11 and the combination of table 1, the cement particle size of example 4 is 100-200 μm, and the granite concrete prepared in example 4 has a compressive strength smaller than that of example 1 and a crack number greater than that of example 1, compared with example 1; the cement particles with large particle size are not easy to disperse in a network structure, so that the bonding effect of granite broken stone and a cementing material is easy to influence, and the mechanical strength of concrete is influenced.

In example 5, no nano filler is added in the polyacrylamide particles, and compared with example 1, the granite concrete prepared in example 5 has compressive strength smaller than that of example 1 and crack number larger than that of example 1; the nano filler in the polyacrylamide particles can be dispersed at the position of the concrete close to the middle-upper part, and the circulation channel of water in the middle-upper part of the concrete in the hydration process of the concrete is filled, so that the structural density of the concrete is improved, and the concrete has higher mechanical strength.

Example 6 the granite concrete prepared in example 6 has a compressive strength less than that of example 1 and a crack number greater than that of example 1, compared with example 1, by replacing the low-viscosity aqueous polyacrylamide solution with the high-viscosity aqueous polyacrylamide solution of the same mass in the polyacrylamide particles; the high-viscosity polyacrylamide aqueous solution is not easy to separate from the surface of the granite broken stone, but is easy to adhere to the surface of the granite broken stone, and although the adhesion of the granite broken stone and the cementing material is ensured to a certain extent, mineral substances in the granite broken stone cannot react with cement particles, and nano fillers cannot be dispersed and filled at the positions of the pores of the concrete, so that the mechanical strength of the concrete is influenced.

In the embodiment 7, the nano filler is prepared by replacing nano silicon nitride with hollow glass beads with the same mass, and compared with the embodiment 1, the granite concrete prepared in the embodiment 7 has the compressive strength smaller than that of the embodiment 1 and the crack number larger than that of the embodiment 1; the hollow glass beads and the nano silicon nitride are matched, so that the hollow glass beads and the nano silicon nitride can be respectively filled in different positions of the internal structure of the concrete, and the mechanical strength of the concrete is improved.

In example 8, no phosphatidylserine was added to the rigid fiber, and in comparison with example 1, the granite concrete prepared in example 8 had a compressive strength less than that of example 1 and a crack number greater than that of example 1; the polypropylene fiber and the phosphatidylserine are matched, and the hydrophilic group in the phosphatidylserine is matched with the diversion effect of the fiber, so that moisture can reach the surface of granite rubble to promote the reaction of cement particles and substances in granite, the bonding effect of the granite rubble and a cementing material is improved, and the concrete has higher mechanical strength.

Example 9 the rigid fibers are chopped glass fibers, and compared with example 1, the granite concrete prepared in example 9 has a compressive strength less than that of example 1 and a crack number greater than that of example 1; the glass fiber chopped filaments have larger density, and the sedimentation effect of the granite broken stone in the concrete is easily influenced by matching with the larger density of the granite broken stone, so that the dispersion uniformity is poor, and the mechanical strength of the concrete is influenced.

In the flexible fiber of example 10, the hydrophobic aluminum silicate fiber cotton is replaced by the aluminum silicate fiber cotton with the same quality, compared with the flexible fiber of example 1, the granite concrete prepared in example 10 has the compressive strength smaller than that of example 1 and the number of cracks larger than that of example 1; it is explained that the aluminum silicate fibers are hydrophilic and have a degree of water absorption, resulting in that the mechanical strength of the concrete is easily affected.

Compared with example 1, the granite concrete prepared in example 11 has compressive strength smaller than that of example 1 and crack number larger than that of example 1, and low-melting agarose is not added in the granite chips of example 11; the low-melting-point agarose can improve the bonding stability of granite chips and other raw materials in the hydration process, so that the compactness of the internal structure of the concrete is improved, and the concrete has higher mechanical strength.

As can be seen by combining example 1 and comparative examples 1-2 and combining table 1, the granite concrete prepared in comparative example 1 has a compressive strength less than that of example 1 and a crack number greater than that of example 1, as compared with example 1, in which the granite chips of comparative example 1 are replaced with granite chips of the same mass and the modified granite chips are replaced with granite chips of the same mass; the surface-treated granite chips and granite gravels can improve the dispersion uniformity of the granite chips and the granite gravels and the bonding effect of the granite chips and the granite gravels and the cementing material, so that the concrete has higher mechanical strength and better durability.

In the preparation process of the modified granite rubble of comparative example 2, rigid fibers and flexible fibers are not added, and compared with the granite concrete prepared in example 1, the compressive strength of the granite concrete prepared in comparative example 2 is smaller than that of example 1, and the number of cracks is larger than that of example 1; the rigid fiber and the flexible fiber are sequentially matched, so that a network structure is formed on the surface of the granite broken stone to load cement particles with smaller particles, the bonding effect of the granite broken stone and the cementing material is improved, and the mechanical strength of the concrete is improved.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

Claims

1. The granite concrete is characterized by comprising the following raw materials in parts by weight: 160-190 parts of cement, 155-190 parts of granite fine powder, 900-950 parts of carrier granite stone chips, 900-1050 parts of modified granite broken stone, 155-180 parts of water, 6-8.5 parts of water reducer and 0.2-1 part of air entraining agent; the modified granite broken stone is prepared by sequentially loading polyacrylamide particles, rigid fibers and flexible fibers on the granite broken stone with the mass ratio of 100:1-8:0.5-1:0.8-1.4;

The polyacrylamide particles are prepared by mixing low-viscosity polyacrylamide aqueous solution and nano filler in a mass ratio of 10:5-8, and then freeze-drying and crushing the mixture; the nano filler consists of nano silicon nitride and hollow glass beads in a mass ratio of 1:1-3; the rigid fiber is prepared from polypropylene fiber, ethylcellulose solution and phosphatidylserine in a mass ratio of 1:0.1-0.2:0.1-0.3; the flexible fiber consists of hydrophobic aluminum silicate fiber cotton and ethyl cellulose solution with the mass ratio of 1:0.15-0.3; the material-carrying granite chips are prepared from granite chips, polyvinyl alcohol solution and low-melting-point agarose in a mass ratio of 100:2-7:2-8;

The carried granite stone chips are prepared by the following method:

Uniformly spraying a polyvinyl alcohol solution on the surface of granite chips, uniformly spraying agarose with a low melting point, and drying and dispersing until the granite chips are free from aggregation and adhesion to prepare the material-carrying granite chips;

the rigid fiber is prepared by the following method:

Uniformly spraying ethyl cellulose solution on the surface of polypropylene fiber, uniformly spraying phosphatidylserine, and drying and dispersing until the polypropylene fiber is not adhered to each other to prepare rigid fiber;

the flexible fiber is prepared by the following method:

Uniformly spraying ethyl cellulose solution on the surface of hydrophobic aluminum silicate fiber cotton, and dispersing until the fibers are not agglomerated and adhered to each other to prepare flexible fibers;

The modified granite broken stone is prepared by the following method:

And (3) spraying a polyacrylamide solution on the surfaces of the polyacrylamide particles, uniformly spraying the polyacrylamide solution on the surfaces of granite gravels, uniformly spraying rigid fibers, uniformly spraying flexible fibers, drying and dispersing until the granite gravels are not agglomerated and adhered to each other, and thus obtaining the modified granite gravels.

2. The granite concrete of claim 1, wherein: the granite stone chips in the material-carrying granite stone chips consist of stone chips with the particle size of 20-75 mu m and stone chips with the particle size of 80-400 mu m in a mass ratio of 1:5-9.

3. The granite concrete of claim 1, wherein: the granite broken stone comprises the following raw materials in parts by weight: 160-200 parts of crushed stone with the grain size of 0.5-1cm, 580-650 parts of crushed stone with the grain size of 1-2cm and 160-200 parts of crushed stone with the grain size of 2-3 cm.

4. The granite concrete of claim 1, wherein: the cement consists of cement particles with the particle size of 10-60 mu m and cement particles with the particle size of 80-200 mu m in a mass ratio of 1:3-5.

5. The method for preparing granite concrete according to any one of claims 1-4, comprising the steps of:

s3, pouring, vibrating and curing the mixture to obtain a finished product.