CN115818995B - Preparation method of basalt sand and cement-based material - Google Patents
Preparation method of basalt sand and cement-based material Download PDFInfo
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- CN115818995B CN115818995B CN202211430644.5A CN202211430644A CN115818995B CN 115818995 B CN115818995 B CN 115818995B CN 202211430644 A CN202211430644 A CN 202211430644A CN 115818995 B CN115818995 B CN 115818995B
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- 239000004576 sand Substances 0.000 title claims abstract description 149
- 239000000463 material Substances 0.000 title claims abstract description 111
- 239000004568 cement Substances 0.000 title claims abstract description 102
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 239000002245 particle Substances 0.000 claims abstract description 255
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 60
- 238000000498 ball milling Methods 0.000 claims abstract description 46
- 239000002994 raw material Substances 0.000 claims abstract description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 144
- XMWRBQBLMFGWIX-UHFFFAOYSA-N C60 fullerene Chemical compound C12=C3C(C4=C56)=C7C8=C5C5=C9C%10=C6C6=C4C1=C1C4=C6C6=C%10C%10=C9C9=C%11C5=C8C5=C8C7=C3C3=C7C2=C1C1=C2C4=C6C4=C%10C6=C9C9=C%11C5=C5C8=C3C3=C7C1=C1C2=C4C6=C2C9=C5C3=C12 XMWRBQBLMFGWIX-UHFFFAOYSA-N 0.000 claims description 42
- 229910003472 fullerene Inorganic materials 0.000 claims description 42
- 239000003638 chemical reducing agent Substances 0.000 claims description 23
- 239000003795 chemical substances by application Substances 0.000 claims description 23
- 239000010881 fly ash Substances 0.000 claims description 23
- 229910021487 silica fume Inorganic materials 0.000 claims description 22
- 238000012216 screening Methods 0.000 claims description 10
- 239000002893 slag Substances 0.000 abstract description 12
- 239000000843 powder Substances 0.000 abstract description 5
- 230000000877 morphologic effect Effects 0.000 abstract description 2
- 238000012360 testing method Methods 0.000 description 43
- 239000004570 mortar (masonry) Substances 0.000 description 36
- 239000002002 slurry Substances 0.000 description 33
- 230000000052 comparative effect Effects 0.000 description 20
- 238000003756 stirring Methods 0.000 description 19
- 238000000034 method Methods 0.000 description 15
- 239000011398 Portland cement Substances 0.000 description 10
- 238000001035 drying Methods 0.000 description 10
- 238000010521 absorption reaction Methods 0.000 description 9
- 238000007580 dry-mixing Methods 0.000 description 9
- 239000012535 impurity Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 7
- 238000002474 experimental method Methods 0.000 description 5
- 230000006835 compression Effects 0.000 description 4
- 238000007906 compression Methods 0.000 description 4
- 241000283070 Equus zebra Species 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000011056 performance test Methods 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 238000001179 sorption measurement Methods 0.000 description 3
- 239000011083 cement mortar Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910052655 plagioclase feldspar Inorganic materials 0.000 description 2
- 229910052611 pyroxene Inorganic materials 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 238000007873 sieving Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 239000005335 volcanic glass Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- 235000011437 Amygdalus communis Nutrition 0.000 description 1
- 241000220304 Prunus dulcis Species 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 235000020224 almond Nutrition 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011411 calcium sulfoaluminate cement Substances 0.000 description 1
- 238000012669 compression test Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 229920005646 polycarboxylate Polymers 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention relates to a preparation method of basalt sand and a cement-based material, wherein the preparation method comprises the following steps: step 1, crushing: crushing basalt to obtain basalt particles; step 2, ball milling: ball milling basalt slag particles to obtain the basalt slag powder. The cement-based material comprises the following raw materials in parts by weight: 80-110 parts of cementing material; 10-60 parts of fine aggregate; 5-35 parts of auxiliary materials; 10-40 parts of water; wherein the fine aggregate adopts the basalt sand. The invention changes the morphological characteristics of basalt sand through ball milling, improves the fluidity and compressive strength of cement-based materials prepared by the basalt sand, and makes the preparation of cement-based materials by taking basalt sand as fine aggregate to replace river sand possible.
Description
Technical Field
The invention belongs to the technical field of cement-based materials, and particularly relates to a preparation method of basalt sand and a cement-based material.
Background
The cement-based material usually takes river sand as fine aggregate, however, along with the rapid development of the construction industry in China, the use amount of the river sand is continuously increased, and the resources are gradually deficient, so that the search for a river sand substitute in the cement-based material to save the river sand resources becomes an urgent problem.
Basalt is the most main composition of the earth ocean shell and is a solid substance which is widely distributed and has huge reserves on the earth; the main components are silicon dioxide, aluminum oxide, ferric oxide and the like, the corrosion resistance is good, the volume density is 2.8-3.3 g/cm, the compression resistance and the fracture resistance of the material are excellent due to a compact structure, and the compression strength can reach 300 MPa; can be used as building fine aggregate.
However, when basalt crushed fine-grain basalt sand is used as fine aggregate of cement-based materials, especially when basalt is crushed into particles of 2.36 or less mm, the cement-based materials have a small fluidity and a low compressive strength due to the flat morphology and the protruding corners, and thus the application of basalt sand as fine aggregate in cement-based materials is limited.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a preparation method of basalt sand and a cement-based material, which change the morphological characteristics of basalt sand through ball milling, improve the fluidity and compressive strength of the cement-based material prepared by the basalt sand, and enable the basalt sand to be used as fine aggregate to replace river sand for preparing cement-based material.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the technical scheme is as follows:
a preparation method of basalt sand comprises the following steps:
step 1, crushing: crushing basalt to obtain basalt particles;
step 2, ball milling: ball milling basalt particles to obtain the product.
As a preferable technical scheme, the basalt particles in the step 1 have the particle size smaller than or equal to 4 mm.
As a preferable technical scheme, the ball milling adopts a ball mill, and the ball milling time of the ball mill is 0.5-2h; the ball milling speed of the ball mill is 400r/min.
As a preferable technical scheme, after the step 2, the method further comprises a step 3;
step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges;
step 3-2, grading basalt particles with different particle size ranges according to a fullerene formula to prepare basalt sand;
the formula of the fullerene is as follows:
wherein: p is the passing percentage,%;
d is the maximum particle size of the aggregate, mm;
n is a coefficient of a fullerene formula, and n=0.3-0.5.
As a preferable technical scheme, the fullerene formula coefficient n=0.4-0.45.
As a preferred technical scheme, the method comprises the following steps,
when the grain diameter range of the basalt sand after grading is 0-0.6mm, the coefficient n=0.4 of the fullerene formula;
when the grain diameter range of the basalt sand after grading is 0-2.36mm, the coefficient n=0.45 of the fullerene formula;
when the grain diameter range of basalt sand after grading is 0.075-2.36mm, the fullerene formula coefficient n=0.4.
The second technical scheme is as follows:
basalt sand prepared by adopting the preparation method.
The technical scheme is as follows:
an application of the basalt sand in preparing cement-based materials.
The technical scheme is as follows:
the cement-based material comprises the following raw materials in parts by weight:
80-110 parts of cementing material;
10-60 parts of fine aggregate;
5-35 parts of auxiliary materials;
10-40 parts of water;
wherein the fine aggregate adopts basalt sand as defined in claim 6,
as a preferable technical scheme, the cementing material adopts cement; the auxiliary material adopts one or more of fly ash, silica fume, an expanding agent and a water reducing agent.
The preferable technical scheme comprises the following raw materials in parts by weight:
the auxiliary materials comprise, by weight, 5-25 parts of fly ash, 0.5-5 parts of silica fume, 0.2-3 parts of an expanding agent and 0.2-2 parts of a water reducer.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, ball milling treatment is carried out on crushed basalt particles, the sphericity of basalt sand is improved through ball milling, the edges and corners of the basalt sand are reduced, the mechanical property of the basalt sand is improved, and the friction resistance is reduced, so that compared with the direct use of crushed basalt particles, the compressive strength of a cement-based material test piece prepared by the method is obviously improved, and the fluidity of cement-based material slurry is also obviously improved.
According to the invention, the ball-milled basalt particles are subjected to particle size grading by using a fullerene formula, when the fullerene formula coefficient n=0.4-0.45, the sizes of solid particles are regularly arranged, the thickness matching is reasonable, and the mixture with the maximum density and the minimum pores can be obtained, so that the prepared test block has higher strength and stronger fluidity.
According to the invention, through ball milling and grading of basalt sand, the compressive strength and fluidity of a cement-based material test piece are improved, so that the replacement of the basalt sand by the river sand as a cement-based material fine aggregate becomes a reality, thereby saving river sand resources, solving the environmental problem caused by basalt slag accumulation and realizing the recycling of basalt slag.
Drawings
FIG. 1 is a graph showing the impact on compressive strength of a cement-based test piece after the crushed basalt sand and the ball-milled basalt sand with particle sizes ranging from 0 mm to 0.6mm are graded according to a Fullerene formula;
FIG. 2 is a graph showing the impact on compressive strength of a cement-based test piece after the crushed basalt sand and the ball-milled basalt sand are graded according to a Fullerene formula, wherein the particle size of the crushed basalt sand is in the range of 0-2.36 and mm;
FIG. 3 is a graph showing the impact on compressive strength of a cement-based test piece after the crushed basalt sand and the ball-milled basalt sand are graded according to a Fullerene formula, wherein the particle size range of the crushed basalt sand is 0.075-2.36. 2.36 mm;
FIG. 4 is a graph showing the effect of crushed basalt sand with a particle size ranging from 0 mm to 0.6mm on the fluidity of cement-based slurry after grading the crushed basalt sand and the ball-milled basalt sand according to a Fullerene formula;
FIG. 5 is a graph showing the effect of crushed basalt sand and ball-milled basalt sand in the size range of 0-2.36. 2.36mm on the fluidity of cement-based slurry after grading according to the Fullerene formula;
FIG. 6 is a graph showing the effect of crushed basalt sand and ball-milled basalt sand in the size range of 0.075-2.36. 2.36mm on the fluidity of cement-based slurry after grading according to the Fullerene formula;
FIG. 7 is a graph showing the effect of ball-milled basalt of different particle size ranges on water absorption of cement-based material test pieces;
FIG. 8 is a graph of the effect of ball-milled basalt of different particle size ranges on the density of cement-based material test pieces.
Detailed Description
The technical solutions of the present invention will be clearly and fully described below with reference to specific embodiments, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the invention, the following components are added:
portland cement is P.O 52.5.5 manufactured by Jiuqiu building materials Co., ltd;
basalt sand is almond glass-based basalt, rock is in a zebra structure, a matrix is a glass crystal interweaving structure, zebra crystals mainly comprise plagioclase (16%) and pyroxene (10%), and the matrix is volcanic glass (50%), plagioclase (10%) and pyroxene (5%). The zebra crystal components are uniformly dispersed in the matrix volcanic glass, the rock is gray black, compact and blocky, and the chemical components are shown in the table 1, wherein IL is a firing vector;
TABLE 1
| Composition of the components | SiO 2 | Al 2 O 3 | Fe 2 O 3 | TiO 2 | CaO | MgO | K 2 O | Na 2 O | IL |
| Basalt powder | 57.96 | 12.74 | 10.15 | 1.13 | 3.01 | 6.38 | 2.44 | 1.7 | 4.35 |
The water reducer is a polycarboxylate water reducer, and the mortar water reduction rate (%) is larger than or equal to 14%;
the expanding agent is calcium sulfoaluminate cement expanding agent;
the fly ash is class I fly ash; silica fume (98%).
In the present invention, the formula of the fullerene used is:
wherein: p is the passing percentage,%;
d is the maximum particle size of the aggregate, mm;
n is a coefficient of a fullerene formula, and n=0.3-0.5.
The present invention will be described in further detail with reference to specific examples.
Examples 1 to 5:
the cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0-0.6 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 1mm, namely basalt particles;
step 2, ball milling: ball milling basalt particles;
the ball milling adopts a ball mill, and the ball milling time of the ball mill is 2 hours; the ball milling speed of the ball mill is 400r/min.
Step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges; in this embodiment, the basalt particles with different particle size ranges include basalt particles with particle sizes less than or equal to 0.075mm, basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm, and basalt particles with particle sizes of 0.3-0.6 mm.
And 3-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-0.6 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0-0.6mm in examples 1-5 is shown in Table 2.
TABLE 2
Examples 6 to 10
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0-2.36 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 3mm, namely basalt particles;
step 2, ball milling: ball milling basalt particles to obtain the product.
The ball milling adopts a ball mill, and the ball milling time of the ball mill is 2 hours; the ball milling speed of the ball mill is 400r/min.
Step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes less than or equal to 0.075mm, basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.6-1.18mm and basalt particles with particle sizes of 1.18-2.36 mm.
And 3-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-2.36 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0-2.36mm in examples 6-10 is shown in Table 3.
TABLE 3 Table 3
Examples 11 to 15
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0.075-2.36 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 3mm, namely basalt particles;
step 2, ball milling: ball milling basalt particles to obtain the product.
The ball milling adopts a ball mill, and the ball milling time of the ball mill is 2 hours; the ball milling speed of the ball mill is 400r/min.
Step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.6-1.18mm and basalt particles with particle sizes of 1.18-2.36 mm.
And 3-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-2.36 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0.075-2.36mm in examples 11-15 is shown in Table 4.
TABLE 4 Table 4
Example 16
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 62.4 parts of basalt sand with the grain diameter of 0-0.6 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 1mm, namely basalt particles;
step 2, ball milling: ball milling basalt particles to obtain the product.
The ball milling adopts a ball mill, and the ball milling time of the ball mill is 2 hours; the ball milling speed of the ball mill is 400r/min.
Step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes more than or equal to 0.6, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.15-0.3mm and basalt particles with particle sizes less than or equal to 0.15.
And 3-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-0.6 mm.
In the embodiment, the grain size grading ratio of the basalt sand with the grain size of 0-0.6mm is shown in table 5;
TABLE 5
| Basalt particle size range/mm | ≥0.6 | 0.3-0.6 | 0.15-0.3 | ≤0.15 |
| Proportion of basalt particles of each size fraction (%) | 0 | 62.7 | 26.0 | 11.3 |
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
Comparative examples 1 to 5
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0-0.6 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 1mm to prepare basalt particles;
step 2, grading:
step 2-1, screening basalt particles obtained by crushing in the step 1 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes less than or equal to 0.075mm, basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm and basalt particles with particle sizes of 0.3-0.6 mm.
And 2-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-0.6 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0-0.6mm in comparative examples 1-5 is shown in Table 6.
TABLE 6
Comparative examples 6 to 10
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0-2.36 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 3mm, namely basalt particles;
step 2, grading:
step 2-1, screening basalt particles obtained by crushing in the step 1 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes less than or equal to 0.075mm, basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.6-1.18mm and basalt particles with particle sizes of 1.18-2.36 mm.
And 2-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-2.36 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0-2.36mm in comparative examples 6-10 is shown in Table 7.
TABLE 7
Comparative examples 11 to 15
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 65 parts of basalt sand with the particle size of 0.075-2.36 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 3mm, namely basalt sand;
step 2, grading:
step 2-1, screening basalt particles obtained by crushing in the step 1 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes of 0.075-0.15mm, basalt particles with particle sizes of 0.15-0.3mm, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.6-1.18mm and basalt particles with particle sizes of 1.18-2.36 mm.
And 2-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-2.36 mm.
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
The grain size grading ratio of basalt sand with the grain size of 0.075-2.36mm in comparative examples 11-15 is shown in Table 8.
TABLE 8
Comparative example 16
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 62.4 parts of basalt sand with the grain diameter of 0-0.6 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the preparation method of the basalt sand comprises the following steps:
step 1, crushing:
removing impurities from basalt slag, drying, and crushing into particles with the particle size less than or equal to 0.6mm, namely basalt particles;
step 2, grading:
step 2-1, screening basalt particles obtained by crushing in the step 1 according to particle sizes, and collecting basalt particles in different particle size ranges; the basalt particles with different particle size ranges comprise basalt particles with particle sizes more than or equal to 0.6, basalt particles with particle sizes of 0.3-0.6mm, basalt particles with particle sizes of 0.15-0.3mm and basalt particles with particle sizes less than or equal to 0.15.
And 2-2, grading basalt particles with different particle size ranges according to a Fullerene formula to obtain basalt sand with the particle size of 0-0.6 mm.
In the comparative example, the grain size grading ratio of basalt sand with the grain size of 0-0.6mm is shown in table 9;
TABLE 9
| Basalt particle size range/mm | ≥0.6 | 0.3-0.6 | 0.15-0.3 | ≤0.15 |
| Proportion of basalt particles of each size fraction (%) | 0 | 62.7 | 26.0 | 11.3 |
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
Comparative example 17
The cement-based material comprises the following raw materials in parts by weight:
cementing material: 52.5 Portland cement 100 parts;
fine aggregate: 62.4 parts of river sand with the particle size of 0-0.6 mm;
15 parts of fly ash;
2 parts of silica fume;
1 part of an expanding agent;
0.45 parts of water reducer;
28.5 parts of water;
the river sand is pretreated before use, and the river sand proportion of different particle size intervals in the river sand is determined;
the river sand pretreatment comprises the following steps: removing impurities from river sand, drying, sieving, and collecting 0.6mm granule.
Determining the proportion of river sand particles in different particle size intervals in the river sand: sieving the sieved river sand according to the particle size, weighing, and calculating to determine the percentage of river sand particles in different particle size ranges, wherein the river sand particles in different particle size ranges comprise river sand particles with the particle size of more than or equal to 0.6, river sand particles with the particle size of 0.3-0.6mm, river sand particles with the particle size of 0.15-0.3mm and river sand particles with the particle size of less than or equal to 0.15;
the percentage ratio of river sand particles in different particle size intervals obtained after weighing is shown in Table 10;
table 10
| River sand particle size range/mm | ≥0.6 | 0.3-0.6 | 0.15-0.3 | ≤0.15 |
| Proportion of river sand particles of each size fraction (%) | 0 | 62.7 | 26.0 | 11.3 |
A method for preparing cement-based material slurry, comprising the steps of:
adding the cementing material, the fly ash, the silica fume, the expanding agent and the water reducing agent into a mortar stirrer, adding water into the mortar stirrer after dry mixing and stirring uniformly, pouring fine aggregate into the mortar stirrer after 30 s low-speed rotation, stirring 30 s at a low speed, and then rotating 90 s at a high speed to prepare cement-based material slurry for later use.
Effect example:
1. the test method comprises the following steps:
1. preparing and maintaining test blocks: the cement-based material slurries prepared in the respective examples and comparative examples were left to stand for 15 to s, respectively, and then added to a test mold. The size of the cement blocks manufactured through experiments is 70.7 mm multiplied by 70.7 mm multiplied by 70.7 mm, the cement blocks are compacted through a vibrating table after stirring, and the cement blocks are demolded after curing at room temperature for 48 h. In the compression test, the demolded test block is maintained in a water bath at 55 ℃ for 7 days, and then the compression strength is tested.
2. Compression strength experiment: the cement mortar compressive strength test method is referred to JGJ/T70-2009 "building mortar basic performance test method Standard". Mortar cube compressive strength (MPa) =1.35 (Nu/a); nu-cube failure pressure (N), A-test piece pressure area (mm) 2 ）。
3. Flow experiment: reference is made to GB/T2419-2004 "cement mortar fluidity determination method"; mortar fluidity instrument (model: NLD-3 type, vibration frequency 1 Hz, vibration plane using 400 mm + -1 mm platform with increased diameter, vibration times 25 times, vibration drop distance 10 mm + -0.2 mm).
4. Water absorption experiment: reference is made to JGJ/T70-2009 Standard for basic Performance test of construction mortar.
5. Density experiment: dry weight, test block density (g/cm) were tested with reference to JGJ/T70-2009 building mortar basic Performance test method Standard 3 ) =g/V; g-dry weight of block (G), V-volume of block (7.07 cm*7.07 cm*7.07 cm).
2. Test results and analysis
1. The influence of the grain size grading ratio (namely the Fullerene formula coefficient n) of basalt sand on the compressive strength of a cement-based test piece is shown in figures 1-3;
as can be seen from fig. 1 to 3, as the value of the fullerene coefficient n increases, the compressive strength of the cement-based material test block prepared from basalt sand having different particle diameters generally tends to increase and decrease, and compared with the basalt sand of comparative examples 1 to 15, which was not ball-milled and only crushed, the strength of the cement-based material test block prepared from basalt sand of examples 1 to 15, which was ball-milled after crushing, was significantly improved, and the effect of basalt sand having a finer particle diameter (0 to 0.6 mm) was more significant.
As can be seen from fig. 1: examples 1-5 when basalt sand with the particle size of 0-0.6mm is used for preparing a cement-based material test block, and when the coefficient n of the Fullerene formula is 0.4, the strength of the cement-based material test block is highest;
as can be seen from fig. 2: examples 6-10 when basalt sand with the particle size of 0-2.36mm is used for preparing a cement-based material test block, and when the coefficient n of the Fullerene formula is 0.45, the strength of the cement-based material test block is highest;
as can be seen from fig. 3: examples 11-15 when basalt sand with the particle size of 0.075-2.36mm is used for preparing a cement-based material test block, and when the coefficient n of the Fullerene formula is 0.4, the strength of the cement-based material test block is the highest;
because the cement-based material has smaller porosity and stable stacking structure and the prepared test block is uniform and compact, the strength and durability of the cement-based test block can be improved, and the skeleton and the stabilizing effect of the fine aggregate can be exerted to the greatest extent. The coarse sand can improve the strength of the mortar, so that the stress in the test block is concentrated, but excessive coarse sand can influence the grading continuity of the material, and more pores are generated. Meanwhile, excessive coarse sand can reduce the drying shrinkage, but can increase the number of microcracks in the cement-based material slurry, and adversely affect the hardening of the cement-based material. The fine sand can effectively improve the stress uniformity of the test block, but the excessive fine sand content is unfavorable for forming good grading, the specific surface area is large, the water absorption of the material is increased, and the strength of the material is also unfavorable.
From the above, it can be seen that: the strength of the cement-based material test block is affected by the grading proportion of basalt sand, so that reasonable grading of basalt sand, coarse sand and fine sand are very important for reasonable configuration.
2. The influence of the grain size grading ratio (namely the Fullerene formula coefficient n) of basalt sand on the fluidity of cement-based material slurry is shown in figures 4-6;
as can be seen from fig. 4-6: as the coefficient n of the Fullerene formula is increased, the fluidity of the cement-based material mortar prepared from basalt sand with different particle sizes obviously increases, and the thinner the particles of the basalt sand are, the lower the fluidity is; the fluidity of the cement-based slurry prepared by ball-milling basalt sand after crushing in examples 1 to 15 was significantly improved as compared with basalt sand of comparative examples 1 to 15, which was not ball-milled and was only crushed.
This may be due to: the coarser particles have lower specific surface area, and the water adsorption capacity of the material is poorer, so that the fluidity of the material is obviously increased; the specific surface area of the fine particles is larger, the water absorption is higher, the adsorption capacity to water is stronger, and when the fine sand content is increased, the more water is adsorbed, the poorer the mortar fluidity is.
3. The influence of basalt sand with different particle size ranges on the water absorption of a cement-based material test piece is shown in fig. 7;
as can be seen from FIG. 7, the basalt sand of examples 1-5 used 0-0.6mm and the basalt sand of examples 11-15 used 0.075-2.36mm, the water absorption of the cement-based test block increased continuously with the increase of the Fullerene coefficient n value; in examples 6-10, basalt sand of 0-2.36. 2.36mm was used, and the water absorption of the cement-based test block was decreased and then increased.
This may be because: the fine particles contain more basalt powder with the particle size of less than 75 and um, and the basalt powder has higher specific surface area and stronger adsorption capacity to water. Along with the increase of the mixing amount of the finer basalt sand in the cement-based material slurry body, the stone powder content is increased along with the increase of the mixing amount of the finer basalt sand, and the more the adsorbed water is, the poorer the fluidity of the cement-based material slurry body is. The free water in the cement-based material slurry body with high fluidity is relatively high, after the test block is dry and hard, more pores are formed in the cement-based material slurry body, and the higher the porosity is, the higher the water absorption of the cement-based material test block is, so that the water absorption of the cement-based material test block is also increased.
4. The influence of basalt sand with different particle size ranges on the density of a cement-based material test piece is shown in fig. 8;
as can be seen from fig. 8: examples 1-5 employed basalt sand of 0-0.6mm, with the overall density of the cement-based test block increasing with increasing value of the fullerene formula coefficient n; while examples 6-10 used basalt sand of 0-2.36mm and examples 11-15 used basalt sand of 0.075-2.36mm, the overall density of the cement-based test block increased and decreased as the value of the Fullerene coefficient n increased;
it can also be seen from fig. 8 that: examples 6-10 employed basalt sand of 0-2.36mm, the density of the cement-based test block was relatively low compared to examples 1-5 and examples 11-15.
5. The impact of different fine aggregates on the compressive property and workability of the cement-based material test pieces is shown in Table 11;
TABLE 11
| Comparative example 17 | Comparative example 16 | Example 16 | |
| Compressive Strength/MPa | 90.11 | 78.52 | 88.63 |
| Fluidity/mm | 340 | 227 | 355 |
As can be seen from the data in table 11: at the same fineness, the compressive strength of the cement-based test block prepared by using the natural river sand in comparative example 17 is obviously higher than that of the cement-based test block prepared by using the basalt sand obtained by crushing in comparative example 16, and the fluidity of the cement-based slurry prepared by using the river sand in comparative example 17 is obviously higher than that of comparative example 16. In contrast, the cement-based test block prepared by using basalt sand obtained by ball milling in example 16 has significantly improved strength compared with the cement-based test block prepared by using crushed basalt sand in comparative example 16, and the fluidity of the cement-based material slurry prepared by using basalt sand obtained by ball milling in example 16 is more than that of the cement-based material slurry prepared by using river sand in comparative example 17.
The above described embodiments are only preferred examples of the invention and are not exhaustive of the possible implementations of the invention. Any obvious modifications thereof, which would be apparent to those skilled in the art without departing from the principles and spirit of the present invention, should be considered to be included within the scope of the appended claims.
Claims (1)
1. The cement-based material is characterized by comprising the following raw materials in parts by weight:
wherein the fine aggregate adopts basalt sand;
the preparation method of basalt sand comprises the following steps:
step 1, crushing: crushing basalt to obtain basalt particles; particles with the particle size of basalt particles being less than or equal to 4mm in the step 1;
step 2, ball milling: ball milling basalt particles; in the step 2, a ball mill is adopted for ball milling, and the ball milling time of the ball mill is 0.5-2h; the ball milling speed of the ball mill is 400r/min;
step 3, grading:
step 3-1, screening basalt particles subjected to ball milling in the step 2 according to particle sizes, and collecting basalt particles in different particle size ranges;
step 3-2, grading basalt particles with different particle size ranges according to a fullerene formula to prepare basalt sand;
the formula of the fullerene is as follows:
wherein: p is the passing percentage,%;
d is the maximum particle size of the aggregate, mm;
n is a fullerene formula coefficient, wherein the fullerene formula coefficient n=0.4-0.45;
when the grain diameter range of the basalt sand after grading is 0-0.6mm, the coefficient n=0.4 of the fullerene formula;
when the grain diameter range of the basalt sand after grading is 0-2.36mm, the coefficient n=0.45 of the fullerene formula;
when the grain diameter range of basalt sand after grading is 0.075-2.36mm, the fullerene formula coefficient n=0.4;
the cementing material adopts cement;
the auxiliary materials comprise, by weight, 5-25 parts of fly ash, 0.5-5 parts of silica fume, 0.2-3 parts of an expanding agent and 0.2-2 parts of a water reducer.
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