CN112521055B - Asphalt concrete and preparation method thereof - Google Patents

Abstract

The application relates to the technical field of concrete preparation, and particularly discloses asphalt concrete and a preparation method thereof. The asphalt concrete comprises broken stone, stone chips, mineral powder and asphalt, wherein the mineral powder comprises fly ash, limestone and far infrared ceramic powder; the preparation method comprises the following steps: the method comprises the steps of mixing broken stones and stone chips uniformly, heating, then putting the mixture into heated asphalt, stirring, adding mineral powder into the stirred asphalt concrete premixed material, and stirring uniformly to obtain the asphalt concrete. The asphalt concrete adopts the mutual matching of the fly ash, the limestone powder and the far infrared ceramic powder in a certain proportion, and the combined action reduces the absorption of the asphalt concrete pavement to sunlight energy, reduces the continuous heating of the pavement, ensures that the asphalt concrete has temperature stability and stronger locking force, enhances the weather resistance of the asphalt concrete, and reduces the phenomena of cracking, sinking, peeling and the like caused by the temperature influence.

Description

Asphalt concrete and preparation method thereof

Technical Field

The application relates to the technical field of concrete preparation, in particular to asphalt concrete and a preparation method thereof.

Background

The asphalt concrete is commonly called asphalt concrete, and is a mixture prepared by manually selecting mineral aggregate with a certain gradation composition, broken stone or crushed gravel, stone chips or sand, mineral powder and the like, and mixing the mineral aggregate, the broken stone or crushed gravel, the stone chips or sand, the mineral powder and the like with a certain proportion of asphalt material under strictly controlled conditions.

However, when the inventor conducts current state investigation on asphalt concrete pavements laid in recent years, the inventor finds that the phenomena of cracks, depressions, peeling and the like appear on part of the asphalt concrete pavements, so that the durability of the asphalt concrete pavements is poor, and most of the asphalt concrete needs to be maintained by crack repair and the like, so that the economic cost is increased; and may seriously affect the safety of the vehicle operation and cause traffic safety accidents.

Disclosure of Invention

In order to improve the durability of an asphalt concrete pavement, the application provides a preparation method of asphalt concrete.

In a first aspect, the present application provides an asphalt concrete, which adopts the following technical scheme:

the preparation method of the asphalt concrete is characterized by comprising the following steps: the composite material comprises the following raw materials in parts by weight:

400-600 parts of macadam

150-230 parts of stone chips

30-80 parts of mineral powder

15-40 parts of asphalt

Wherein the mineral powder comprises fly ash, limestone powder and far infrared ceramic powder, and the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1: (6-10): (15-20).

When the inventors studied asphalt concrete, they found that the asphalt concrete was broken, dented, and peeled off, which are caused by the characteristics of asphalt in most cases. The asphalt shows plastic flow under long-term sunlight irradiation, namely under the condition of higher temperature; and in cold weather, i.e. at lower temperatures, appears to be hard and brittle. However, the inventors have studied on asphalt concrete and found that asphalt concrete without mineral powder is more likely to be broken after a certain period of time than asphalt concrete pavement with mineral powder, and thus the inventors speculate that the durability of asphalt concrete is related to mineral powder. In summary, the inventors have searched for a material capable of improving the performance of asphalt concrete from the ore powder and studied the durability of asphalt concrete.

By adopting the technical scheme, the broken stones, the stone chips, the mineral powder and the like are used as main aggregates of the asphalt concrete, and the asphalt is matched, so that the pavement prepared from the asphalt concrete has strong durability. Wherein, the mineral powder is selected from fly ash, limestone powder and far infrared ceramic powder, and the three powders form cementing material with asphalt and have stronger binding power. The wall of the coal ash has a porous structure, the porosity is as high as 50% -80%, and the coal ash has strong water absorption performance. The fly ash is used as one of main components of the mineral powder, and the excellent water absorption performance enables the asphalt concrete to evaporate and release water stored inside when the temperature is higher, so that the asphalt concrete is cooled; since the asphalt concrete is usually black, the absorption of sunlight is high, and the temperature of the asphalt concrete is increased. And far infrared ceramic powder can radiate more far infrared rays than normal objects. When the inventor selects the types of the mineral powder for the asphalt concrete, the inventor finds that the far infrared ceramic powder can slow down the temperature rise of the asphalt concrete and reduce the absorbed energy after being fused with the asphalt under the high-temperature condition, and supposes that the far infrared ceramic powder reflects sunlight together when radiating far infrared rays so as to reduce the influence of the temperature on the asphalt concrete; the limestone powder has a certain three-dimensional space structure and good dispersibility, and is matched with the fly ash and the far infrared ceramic powder to increase the dispersibility of the mineral powder in the asphalt concrete.

Meanwhile, larger internal friction resistance exists among the fly ash, the limestone powder and the far infrared ceramic powder particles, so that the locking force among the asphalt concrete aggregates is enhanced. The large surface area of the fly ash and the limestone powder enables the asphalt material to form a film, and the bonding strength and the temperature stability of the asphalt concrete are improved. The coal ash, the limestone powder and the far infrared ceramic powder are matched with each other and act together to reduce the absorption of sunlight energy of the asphalt concrete pavement, reduce the continuous temperature rise of the pavement, ensure that the asphalt concrete has temperature stability and stronger locking force, enhance the weather resistance and durability of the asphalt concrete, and reduce the phenomena of cracks, depressions, peeling and the like caused by the temperature influence.

Preferably, the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1: (6-8): (18-20).

Through the technical scheme, through a plurality of tests of the inventor, the matching effect of the fly ash, the limestone powder and the far infrared ceramic powder is good in the proportion range, the excellent weather resistance is shown, and the weather resistance of the asphalt concrete is further enhanced.

Preferably, the particle size of the fly ash and the limestone powder is less than 75 μm.

By adopting the technical scheme, the fly ash and the limestone powder with the particle size range of less than 75 mu m have huge surface areas, and the bonding strength between the asphalt concrete aggregates is further improved.

Preferably, the particle size of the far infrared ceramic powder is 0.1-1mm.

By adopting the technical scheme, the far infrared ceramic powder with the particle size range of 0.1-1mm has obvious effect of slowing down the temperature rise of the asphalt concrete through a plurality of tests.

Preferably, the crushed stones comprise coarse crushed stones, medium crushed stones and fine crushed stones, wherein the particle sizes of the coarse crushed stones, the medium crushed stones and the fine crushed stones are as follows:

the particle size range of the coarse crushed stone is 11-17mm;

the particle size range of the medium crushed stone is 7-11mm;

the particle size range of the fine crushed stone is 4-7mm;

preferably, the weight ratio of the coarse crushed stone to the medium crushed stone to the fine crushed stone is 1:1.8-2:1-1.5.

By adopting the technical scheme, the broken stones with different grain diameters are used as the aggregates of the asphalt concrete, and the gaps among the aggregates are small, so that the compacted asphalt concrete pavement has high compactness, the structural framework strength of the asphalt concrete is enhanced, and the durability of the asphalt concrete is favorably prolonged.

Preferably, the asphalt concrete further comprises a toughening agent, wherein the toughening agent accounts for 1-3wt% of the total amount of the asphalt concrete.

Preferably, the toughening agent comprises a rubber powder.

By adopting the technical scheme, the rubber powder is used as the toughening agent, so that the adhesive property is strong, and when the toughening agent accounts for 1-3wt% of the total weight of the asphalt concrete, the adhesive property is excellent. The rubber powder has certain chemical action force inside, so that the adhesive effect on substances is formed, and the rubber powder is used as an auxiliary agent of the asphalt concrete and forms a compound synergistic effect with the asphalt, so that the adhesive force between the aggregates of the asphalt concrete is improved, the phenomenon that the asphalt concrete is cracked is reduced, and the durability of the asphalt concrete is favorably prolonged.

In a second aspect, the present application provides a method for preparing asphalt concrete, which adopts the following technical scheme: the method comprises the following steps:

s1: mixing the broken stone and the stone chips, and heating to 200-230 ℃;

s2: heating the asphalt to 180-200 ℃, adding a toughening agent, and stirring;

s3: adding the aggregate heated to the specified temperature in the step S1 and the asphalt heated to the specified temperature in the step S2 into a stirring container, and stirring for 60-100S to obtain an asphalt concrete premixed material;

s4: and (4) adding mineral powder into the asphalt concrete premixed material stirred in the step (S3), and stirring for 50-80S.

By adopting the technical scheme, the concrete with good durability can be obtained by respectively heating the materials such as the broken stone, the stone chips, the asphalt, the flexibilizer and the like, and the concrete is simple in production process and convenient for mass production of construction engineering.

In summary, the present application has the following beneficial effects:

1. as the coal ash, the limestone powder and the far infrared ceramic powder are simultaneously used as the mineral powder, larger internal friction resistance exists among particles, and the locking force among the asphalt concrete aggregates is enhanced. The mineral powder forms a film in the asphalt material, so that the bonding strength and the temperature stability of the asphalt concrete are improved. The mineral powder is matched with each other, so that the absorption of sunlight energy on the asphalt concrete pavement is reduced, the continuous temperature rise of the pavement is slowed down, the weather resistance and the durability of the asphalt concrete are enhanced, and the phenomena of cracks, depressions, peeling and the like caused by the temperature influence are reduced;

2. the toughening agent is added, so that the bonding force among the asphalt concrete aggregates is improved, the phenomenon of cracking of the asphalt concrete is reduced, and the durability of the asphalt concrete is prolonged;

3. according to the method, the broken stone, the stone chips, the asphalt, the flexibilizer and other materials are respectively heated and mixed to obtain the concrete with good durability, the production process is simple, and mass production of construction engineering is facilitated.

Detailed Description

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

Some of the raw material sources in the following examples are shown in table 1:

name of raw materials	Type number	Source of raw materials
			Crushing stone	Black gravel 1-2	Min-Rich gardens, inc. of England City
Far infrared ceramic powder	A641	Lingshou county vibrating quartz mineral product processing factory
			Limestone powder	YW0001	Jiangyin Yongwang chemical Co., ltd
Fly ash	FMH	Lingshou county \22426
			Rubber powder (nitrile rubber)	GM50	Jingjiang Guangshen rubber and plastic material plant
Asphalt	10#	Fuji-Nanchen chemical Co Ltd

Raw material treatment: and (3) crushed stone screening: and screening the crushed stones into coarse crushed stones, medium crushed stones and fine crushed stones by adopting a crushed stone vibrating screen. Wherein the particle size range of the coarse crushed stone is 11-17mm; the particle size range of the medium crushed stone is 7-11mm; the particle size range of the fine crushed stone is 4-7mm.

Example 1

The asphalt concrete comprises the following raw materials: the gravel comprises crushed stone, stone chips, mineral powder and asphalt, wherein the crushed stone comprises coarse crushed stone, medium crushed stone and fine crushed stone, and the weight ratio of the coarse crushed stone to the medium crushed stone to the fine crushed stone is 1:1.9:1.25; the mineral powder comprises fly ash with the particle size of 0.1mm, limestone powder and far infrared ceramic powder, wherein the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1:6:20, prepared by the following steps:

s1: the method comprises the following steps of proportioning materials in an aggregate weighing scale, weighing 12kg of coarse gravel, 22.9kg of medium gravel and 15.1kg of fine gravel, and 15kg of stone chips, heating in a burner, and heating to 200 ℃;

s2: heating asphalt to 200 ℃;

s3: simultaneously adding the aggregate heated to the specified temperature in the S1 and the asphalt heated to the specified temperature in the S2 into a stirring cylinder for stirring for 60S to obtain an asphalt concrete premixed material;

s4: and (3) adding 0.3kg of fly ash, 1.8kg of limestone powder and 5.9kg of mineral powder of far infrared ceramic powder into the stirred asphalt concrete premixed material in the step (S3), and stirring for 50S.

Example 2

An asphalt concrete comprises the following raw materials: the gravel comprises crushed stone, stone chips, mineral powder and asphalt, wherein the crushed stone comprises coarse crushed stone, medium crushed stone and fine crushed stone, and the weight ratio of the coarse crushed stone to the medium crushed stone to the fine crushed stone is 1:2:1.5; the mineral powder comprises fly ash with the particle size of 0.1mm, limestone powder and far infrared ceramic powder, wherein the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1:8:18, prepared by the following steps:

s1: proportioning materials in an aggregate weighing scale, weighing 8.9kg of coarse gravel, 17.8kg of medium gravel and 13.3kg of fine gravel, and 23kg of stone chips, heating in a burner, and heating to 220 ℃;

s2: heating the asphalt to 180 ℃;

s3: simultaneously adding the aggregate heated to the specified temperature in the S1 and the asphalt heated to the specified temperature in the S2 into a stirring cylinder for stirring for 80S to obtain an asphalt concrete premixed material;

s4: and (3) adding 0.2kg of fly ash, 1.5kg of limestone powder and 3.3kg of mineral powder of far infrared ceramic powder into the stirred asphalt concrete premixed material in the step (S3), and stirring for 80S.

Example 3

The asphalt concrete comprises the following raw materials: the gravel comprises crushed stone, stone chips, mineral powder and asphalt, wherein the crushed stone comprises coarse crushed stone, medium crushed stone and fine crushed stone, and the weight ratio of the coarse crushed stone to the medium crushed stone to the fine crushed stone is 1:1.8:1; the mineral powder comprises fly ash with the particle size of 0.1mm, limestone powder and far infrared ceramic powder, wherein the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1:

s1: the method comprises the following steps of proportioning materials in an aggregate weighing scale, weighing 15.8kg of coarse gravel, 28.4kg of medium gravel and 15.8kg of fine gravel, and 19.5kg of stone chips, heating in a burner, and heating to 230 ℃;

s2: heating the asphalt to 190 ℃;

s3: simultaneously adding the aggregate heated to the specified temperature in the step S1 and the asphalt heated to the specified temperature in the step S2 into a stirring cylinder for stirring for 100S to obtain an asphalt concrete premixed material;

s4: and (3) adding 0.1kg of fly ash, 1.2kg of limestone powder and 1.7kg of mineral powder of far infrared ceramic powder into the stirred asphalt concrete premixed material in the step (S3), and stirring for 70S.

Example 4

The difference between the embodiment and the embodiment 2 is that the addition amounts of the fly ash, the limestone powder and the far infrared ceramic powder in S3 are respectively 0.2kg, 1.3kg and 3.5, and the weight parts of the fly ash, the limestone powder and the far infrared ceramic powder are 1:7:19.

example 5

The difference between this example and example 2 is that the particle size of fly ash and limestone powder in the mineral powder is 0.075mm.

Example 6

The difference between this example and example 2 is that the particle size of fly ash and limestone powder in the mineral powder is 0.06mm.

Example 7

This example is different from example 5 in that the particle size of the far infrared ceramic powder in the ore powder is 0.5mm.

Example 8

This example is different from example 5 in that the particle size of the far infrared ceramic powder in the ore powder is 1mm.

Example 9

The difference between this example and example 7 is that coarse crushed stone was used as the crushed stone in the raw material.

Example 10

This example differs from example 7 in that fine crushed stone was used as the crushed stone in the raw material.

Example 11

The difference between the present example and example 7 is that the addition amount of coarse crushed stone, medium crushed stone and fine crushed stone in the raw crushed stone was 10kg, 10kg and 20, and the weight ratio of the coarse crushed stone, medium crushed stone and fine crushed stone was 1:1:2.

example 12

The difference between the embodiment and the embodiment 7 is that the asphalt also comprises a toughening agent, in the embodiment of the application, the toughening agent is rubber powder with the mass of 0.4kg, S2, after the asphalt is heated to 180 ℃, 0.4kg of rubber powder is added into hot asphalt liquid, and the mixture is uniformly stirred.

Example 13

This example is different from example 12 in that the amount of the rubber powder added in this example is 0.8kg.

Example 14

This example is different from example 12 in that the amount of the rubber powder added in this example is 1.2kg.

Comparative example 1

The difference from example 2 is that in the raw materials of the comparative example, the ore powder is iron ore powder, and the rest is the same as example 2.

Comparative example 2

The difference from example 2 is that in the raw material of the comparative example, the mineral powder is limestone powder, and the rest is the same as example 2.

Comparative example 3

The difference from example 2 is that in the raw material of the comparative example, the mineral powder is fly ash, and the rest is consistent with example 2.

Comparative example 4

The difference from the example 2 is that in the raw material of the comparative example, the mineral powder is far infrared ceramic powder, and the rest is consistent with the example 2.

Comparative example 5

The difference from the example 2 is that in the raw materials of the comparative example, the mineral powder is the fly ash and the far infrared ceramic powder, the addition amount of the fly ash and the far infrared ceramic powder is 0.2kg and 3.3kg, and the others are consistent with the example 2.

Comparative example 6

The difference from the example 2 is that in the raw materials of the comparative example, the mineral powder is limestone powder and far infrared ceramic powder, the addition amount of the limestone powder and the far infrared ceramic powder is 1.5kg and 3.3kg, and the others are consistent with the example 2.

Comparative example 7

The difference from the example 2 is that in the raw materials of the comparative example, the mineral powder is limestone powder and fly ash, the addition amounts of the limestone powder and the fly ash are 1.5kg and 0.2kg, and the others are consistent with the example 2.

Performance test

Test samples: the asphalt concretes obtained in examples 1 to 14 were used as test samples 1 to 14, and the asphalt concretes obtained in comparative examples 1 to 2 were used as control samples 1 to 2.

The test method comprises the following steps: the basic performance detection is carried out on the test samples 1-14 and the control samples 1-2 according to the regulations in road engineering asphalt and asphalt mixture test regulations (JTG E20-2011), and the detection results are as follows:

table 2 asphalt concrete basic performance test table:

combining samples 1-3 with control sample 1, and combining the data from table 2, it can be seen that the asphalt concrete with the selected mineral fines added thereto has improved penetration and softening point and greater marshall stability than the asphalt concrete with iron fines added as the material for the mineral fines. Test results show that the asphalt concrete adopts the fly ash, the limestone powder and the far infrared ceramics as the mineral powder, so that the performance of the asphalt can be improved, and the fracture of an asphalt concrete pavement can be reduced.

By combining the samples 1-3 and the reference samples 2-7 and combining the data in table 2, it can be seen that when the fly ash, the limestone powder and the far infrared ceramic are selected as the mineral powder, the penetration and the softening point of the asphalt are both improved compared with the reference samples 2-7, the compactness is also improved to a certain extent, and the marshall stability is higher than that of the reference samples 2-7, which indicates that the fly ash, the limestone powder and the far infrared ceramic are compounded, the interaction force among mineral powder particles enables the interior of the asphalt concrete to have stronger locking force, and the phenomena of cracks, peeling and the like are reduced, and the experimental data shows that the basic performance of the asphalt concrete is improved after the fly ash, the limestone powder and the far infrared ceramic are compounded.

By combining the samples 5 to 8 with the sample 2, the samples 9 to 11 and the sample 7 and combining the data in the table 2, it can be seen that the particle sizes of the fly ash, the limestone powder and the far infrared ceramic powder in the mineral powder have certain influence on the performance of the asphalt concrete, and the smaller the particle size is, the higher the compactness of the asphalt concrete is. The mineral powder with proper particle size enables the asphalt concrete to have higher Marshall stability, which shows that the interaction and the integrity of an asphalt concrete system are enhanced, thereby improving the high-temperature stability and the low-temperature crack resistance of the asphalt concrete, reducing the generation of temperature shrinkage cracks and slowing the extension of reflection cracks. And the broken stones with uniform particle size and different sizes are used as the aggregates of the asphalt concrete, so that the compactness of the asphalt concrete is improved, the porosity is reduced, the interaction force among the aggregates is strong, the integral strength of the asphalt concrete is improved, and further, the generation of cracks is reduced.

Combining samples 12-14 with sample 7, and as can be seen from the data in table 2, the addition of the rubber powder improves the marshall stability of the asphalt concrete, which indicates that the rubber powder and the asphalt are mutually matched and interacted, thereby enhancing the toughness of the asphalt concrete system, improving the overall strength of the asphalt concrete, and enhancing the crack resistance of the asphalt concrete pavement.

2. Asphalt concrete rut test (high temperature stability test)

The test method comprises the following steps: and (3) carrying out a rutting test on the sample and the comparative sample according to a specified method (T0719-2011), and preparing a block-shaped test piece with the size of a block sample of 300mm in length, 300mm in width and 50-10mm in thickness from the asphalt concrete, and carrying out a test by using a new tire with the wheel pressure of 0.7Mpa at the test temperature of 60 ℃. The test wheel walks 220-250mm on the plate sample at a reciprocating rolling speed of 42 times/min for 3 rolling experiments, the average value is taken as test data, and the test results are shown in table 3.

Table 3 high temperature stability test data table for asphalt concrete:

by combining the samples 1 to 3 and the control samples 1 to 7 and combining the data in table 3, it can be seen that the rutting stability of the asphalt concrete is significantly improved when one or two of the fly ash, the limestone powder and the far infrared ceramic powder are added as the mineral powder, compared with the case where the iron ore powder is used as the mineral powder. And when the fly ash, the limestone powder and the far infrared ceramic powder are used as the mineral powder, the rutting stability degree of the asphalt concrete is obviously improved, which shows that the asphalt concrete and the asphalt of the mineral powder form a compounding effect, and the interaction among the substances shows that the rutting stability degree of the asphalt concrete is improved, so that the high-temperature stability is improved, and the cracking of an asphalt concrete pavement can be reduced.

It can be seen from the data in table 3 by combining samples 5-8 and 2, that the particle sizes of the fly ash, limestone powder and far infrared ceramic powder in the mineral powder have a certain influence on the rutting stability of the asphalt concrete, and when the particle sizes of the limestone and fly ash are 0.075mm, the mineral powder shows excellent rutting stability, i.e. has better high-temperature stability

Combining samples 9-11 and sample 7, and combining the data in table 3, it can be seen that aggregate with a single particle size affects the rutting stability of asphalt concrete, and crushed stones with uniform particle sizes and different sizes are used as the aggregate of asphalt concrete, and the rutting stability is high, which is presumed to be caused by the fact that because of the single particle size, when the crushed stones are mixed and compacted with asphalt to form an asphalt concrete pavement, the spacing between aggregates is large, and when the crushed stones are tilted by test wheels, the aggregates move close to each other, so that the rutting stability is slightly higher than that of sample 7, and further the possibility of crack generation is increased.

Combining samples 12-14 with sample 7, and combining the data from tables 2 and 3, it can be seen that the compaction decreased slightly but the rut stability increased after the addition of rubber powder, which indicates that the rubber powder greatly enhanced the toughness and bonding strength between the aggregates, so that the test wheel showed excellent rut stability when it was plunged.

3. Low temperature bending failure test

The experimental method comprises the following steps: according to the method for manufacturing asphalt concrete specimens (JTJ 052-2000) defined method, 3 specimens of each sample, which are prismatic specimens 250mm in length, 300mm in width and 35mm in thickness, were molded by a wheel milling method, were subjected to a low-temperature bending failure test, and the average value was taken as test data, and the test results are shown in Table 4.

Table 4 table of asphalt concrete low temperature bending failure test data:

it can be seen from the data in table 4 by combining the samples 1 to 3 and the comparative samples 1 to 7 that when one or two of the fly ash, the limestone powder and the far infrared ceramic powder are added as the mineral powder, the low-temperature bending failure strain coefficient of the asphalt concrete is improved compared with the case of using the iron ore powder as the mineral powder. When the fly ash, the limestone powder and the far infrared ceramic powder are used as the mineral powder, the low-temperature bending failure strain coefficient of the asphalt concrete is obviously improved, which shows that the asphalt concrete and the asphalt of the mineral powder form a compounding effect, and the interaction among the substances shows that the low-temperature crack resistance of the asphalt concrete is improved, so that the low-temperature stability is improved, and the cracking of an asphalt concrete pavement can be reduced.

Combining samples 9-11 with sample 7, and combining the data in table 4, it can be seen that the aggregate with a single particle size may affect the low temperature bending failure strain coefficient of the asphalt concrete, which may be caused by the large distance between the crushed stones and the shrinkage between the aggregates under low temperature conditions, resulting in the generation of cracks; the crushed stone particle size ranges are respectively coarse crushed stone, medium crushed stone and fine crushed stone, the mineral powder and the asphalt are uniformly dispersed with the crushed stone, the space between aggregates is small, interaction force exists between the crushed stones, the low-temperature bending failure strain coefficient is improved, and further the low-temperature crack resistance is improved.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims (1)

1. The preparation method of the asphalt concrete is characterized by comprising the following steps: the composite material comprises the following raw materials in parts by weight:

400-600 parts of macadam

150-230 parts of stone chips

30-80 parts of mineral powder

15-40 parts of asphalt

A toughening agent, wherein the toughening agent accounts for 1-3wt% of the total amount of the crushed stone; the toughening agent comprises rubber powder;

the mineral powder comprises fly ash, limestone powder and far infrared ceramic powder, and the weight ratio of the fly ash to the limestone powder to the far infrared ceramic powder is 1: (6-8): (18-20);

the particle size of the fly ash and the limestone powder is less than 75 mu m; the particle size of the far infrared ceramic powder is 0.1-1mm;

the macadam comprises coarse macadam, medium macadam and fine macadam, wherein the particle sizes of the coarse macadam, the medium macadam and the fine macadam are as follows:

the particle size range of the coarse crushed stone is 11-17mm;

the particle size range of the medium crushed stone is 7-11mm;

the particle size range of the fine crushed stone is 4-7mm;

wherein the weight ratio of the coarse crushed stone to the medium crushed stone to the fine crushed stone is 1:1.8-2:1-1.5;

the preparation method comprises the following steps:

s1: mixing broken stone and stone chips to serve as aggregate of asphalt concrete, and heating to 200-230 ℃;

s2: heating the asphalt to 180-200 ℃, adding a toughening agent, and stirring;

s3: adding the aggregate heated to the specified temperature in the step S1 and the asphalt heated to the specified temperature in the step S2 into a stirring container, and stirring for 60-100S to obtain an asphalt concrete premixed material;

s4: and (4) adding mineral powder into the asphalt concrete premixed material stirred in the step (S3), and stirring for 50-80S.