1. The steel slag asphalt concrete is characterized by being prepared from mineral aggregate, asphalt, a viscosity additive and a reinforcing filler, wherein the weight ratio of the mineral aggregate to the asphalt is 4-4.5%, the mixing amount of the viscosity additive is 0.3-0.4% of the total weight of the mineral aggregate and the asphalt, and the mixing amount of the reinforcing filler is 0-0.6% of the total weight of the mineral aggregate and the asphalt;

the mineral aggregate is prepared by mixing the following raw materials in percentage by weight: 33-36% of coarse steel slag, 47-52% of fine steel slag, 10-13% of limestone and 4-6% of mineral powder.

2. The steel slag asphalt concrete according to claim 1, wherein the particle size of the coarse steel slag is 10-15mm, and the asphalt of the fine steel slag is 5-10 mm.

3. The steel slag asphalt concrete according to claim 1, wherein the reinforcing filler is formed by mixing glass beads and glass fibers in a weight ratio of 1: 1-2.

4. The preparation method of the steel slag asphalt concrete as claimed in any one of claims 1 to 3, which is characterized by comprising the following steps:

s1, accurately weighing the coarse steel slag, the fine steel slag and the limestone according to the proportion, and uniformly mixing to obtain primary aggregate;

s2, heating the primary aggregate to 185-190 ℃, adding the viscosity additive, and uniformly stirring to obtain a primary mixture;

and S3, adding preheated asphalt into the primary mixture according to the proportion, and uniformly stirring to obtain the steel slag asphalt concrete.

5. A steel slag asphalt concrete pavement, which is characterized in that the steel slag asphalt concrete pavement is paved by the steel slag asphalt concrete in claim 4.

6. The construction method of the steel slag asphalt concrete pavement as claimed in claim 5, characterized by comprising the following steps:

paving steel slag asphalt concrete on a roadbed, wherein the temperature of the steel slag asphalt concrete is 170-185 ℃ during paving;

after paving, performing to-and-fro primary rolling on the road surface for 3-4 times;

and after primary rolling, secondary rolling is carried out, and the rolling is carried out once again and again.

7. The method as claimed in claim 6, wherein the paving process comprises spreading the mixture in two steps on the road bed, leaving a 50-100mm spreading layer on the spread mixture, and removing the seams by thermal welding.

8. The construction method of a steel slag asphalt concrete pavement according to claim 6, characterized in that the temperature of the pavement is not lower than 160 ℃ during the primary rolling and 90-95 ℃ during the secondary rolling.

Background

At present, along with the increase of the production amount of steel materials, the amount of steel slag generated in the steel-making process is gradually increased, and if the waste steel slag is not effectively treated, a large amount of land resources are occupied, and meanwhile, the ecological environment is also adversely affected.

In order to save sandstone resources and protect ecological environment, the waste steel slag can be used for filling building base layers and road beds at present, and can be mixed with asphalt, mineral aggregate and the like to form aggregate for road surfaces for paving concrete roads. The pavement formed by paving the steel slag asphalt aggregate has good water drainage and permeability, certain high-temperature stability and water stability, and is obviously superior to the pavement performance of the traditional asphalt mixture pavement in the aspect of pavement, so the steel slag has more and more extensive attention in the aspect of pavement.

Compared with natural rocks, the steel slag has a porous saccular structure and can absorb more asphalt, so that in the mixing process of the mixture, the steel slag can easily cause other aggregates to be wrapped by the asphalt, the phenomenon of 'material whitening' is easily caused, and the integral stability and the water stability of the pavement are reduced. For this reason, the current solution is to improve with viscosity additives. However, although the viscosity additive can improve the phenomenon of "white material", the pavement formed by paving the steel slag mixture still has the problem of low stability in the actual operation process, and needs to be further improved.

Disclosure of Invention

In order to improve the bearing strength of the steel slag asphalt concrete pavement, the application provides steel slag asphalt concrete, a preparation method thereof, the pavement and a construction method.

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

the steel slag asphalt concrete is prepared from mineral aggregate, asphalt, a viscosity additive and a reinforcing filler, wherein the weight ratio of the mineral aggregate to the asphalt is 4-4.5%, the mixing amount of the viscosity additive is 0.3-0.4% of the total weight of the mineral aggregate and the asphalt, and the mixing amount of the reinforcing filler is 0-0.6% of the total weight of the mineral aggregate and the asphalt;

the mineral aggregate is prepared by mixing the following raw materials in percentage by weight: 33-36% of coarse steel slag, 47-52% of fine steel slag, 10-13% of limestone and 4-6% of mineral powder.

By adopting the technical scheme, limestone is used as stone material, has good adhesion effect with asphalt, can improve the overall strength and water stability of the steel slag asphalt concrete, has filling effect on mineral powder, can reduce gaps in the steel slag asphalt concrete, and can enhance the strength and stability of a steel slag asphalt concrete pavement, the viscosity additive can enhance the viscosity between the asphalt and the mineral material, and can enhance the stability of the steel slag asphalt concrete and reduce the possibility of mutual separation between mixtures while reducing the phenomenon of 'white materials'.

The coarse steel slag and the fine steel slag with different specifications are mixed into the mixture, the coarse steel slag can form a basic structure of the steel slag asphalt concrete, meanwhile, the fine steel slag can be filled in gaps formed by the coarse steel slag, the coarse steel slag and the fine steel slag which are mutually filled can form a stable steel slag asphalt concrete pavement structure, other raw materials can be filled between the coarse steel slag and the fine steel slag and can form effective adhesion with the coarse steel slag and the fine steel slag, and the overall stability of the steel slag asphalt concrete is further improved.

Preferably, the particle size of the coarse steel slag is 10-15mm, and the pitch of the fine steel slag is 5-10 mm.

By adopting the technical scheme, the gap formed by the coarse steel slag can be filled with the fine steel slag, so that a stable steel slag asphalt concrete pavement structure can be formed, and the stability of the steel slag asphalt concrete is enhanced.

Preferably, the reinforcing filler is formed by mixing glass beads and glass fibers in a weight ratio of 1: 1-2.

By adopting the technical scheme, the glass fiber can form a space network structure in the steel slag asphalt concrete, plays a role of reinforcing rib, can enhance the strength and stability of the steel slag asphalt concrete, and the glass microspheres have high strength and good chemical stability and can enhance the strength of the steel slag asphalt concrete; in addition, the glass beads can be filled in a space network structure formed by glass fibers and used together with the glass fibers, so that the overall stability of the steel slag asphalt concrete can be better enhanced.

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

the preparation method of the steel slag asphalt concrete comprises the following steps:

s1, accurately weighing the coarse steel slag, the fine steel slag and the limestone according to the proportion, and uniformly mixing to obtain primary aggregate;

s2, heating the primary aggregate to 185-190 ℃, adding the viscosity additive, and uniformly stirring to obtain a primary mixture;

and S3, adding preheated asphalt into the primary mixture according to the proportion, and uniformly stirring to obtain the steel slag asphalt concrete.

By adopting the technical scheme, the primary mixture is prepared, the coarse steel slag, the fine steel slag, the limestone and the viscosity additive are uniformly mixed in advance, and then the asphalt is added for mixing, so that the modification of the asphalt by the viscosity additive can be facilitated, and meanwhile, the asphalt can be uniformly wrapped on the surface of the mineral aggregate, and the aim of enhancing the stability of the road mixture can be achieved.

In a third aspect, the present application provides a steel slag asphalt concrete pavement, which adopts the following technical scheme:

a steel slag asphalt concrete pavement is formed by laying steel slag asphalt concrete.

In a fourth aspect, the application provides a construction method of a steel slag asphalt concrete pavement, which adopts the following technical scheme:

a construction method of a steel slag asphalt concrete pavement comprises the following steps:

paving steel slag asphalt concrete on a roadbed, wherein the temperature of the steel slag asphalt concrete is 170-185 ℃ during paving;

after paving, performing to-and-fro primary rolling on the road surface for 3-4 times;

and after primary rolling, secondary rolling is carried out, and the rolling is carried out once again and again.

Preferably, in the paving process, the roadbed is paved in two steps, 50-100mm of paving layers are left on the paved mixture part, and the seams are eliminated in a hot seam mode.

By adopting the technical scheme, the steel slag asphalt concrete pavement is paved, and meanwhile, gaps generated in the paving process are conveniently eliminated.

Preferably, the temperature of the pavement is not lower than 160 ℃ during primary rolling, and is 90-95 ℃ during secondary rolling.

By adopting the technical scheme, the possibility of generating gaps among the mixed materials due to overhigh or overlow temperature is reduced.

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

1. according to the steel slag asphalt concrete structure, the coarse steel slag is utilized to form the basic structure of the steel slag asphalt concrete, and the fine steel slag is utilized to fill the gaps between the coarse steel slag, so that a stable steel slag asphalt concrete structure can be formed, and the stability of the steel slag asphalt concrete is improved.

2. The steel slag asphalt concrete is characterized in that a space network structure is formed in asphalt by utilizing glass fibers, and glass beads are filled in the space network structure, so that the stability of the steel slag asphalt concrete is further improved by utilizing the compounding of the glass fibers and the glass beads.

3. This application is at the pavement in-process of laying, through the temperature of control mixture, has reduced and has spread the possibility that more space appears and influence road surface stability in the completion back mixture.

Detailed Description

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

The asphalt in this application was purchased from Guangdong Li Xin energy Co., Ltd., Cat No. 188-; the steel slag is purchased from Jiangsu permanent steel group Limited company, and the specification is 10-15mm and 5-10 mm; limestone was purchased from the Yongman lime plant in the east Bao region of Jingmen; mineral powder is purchased from the friendship ultrafine powder company, Zhang Jia, City; the viscosity additive was purchased from Sichuan Patch traffic science and technology, Inc., model DHVA; the glass fiber is purchased from Shandong Xingmeng engineering materials Co, and has the specification of 15 mm; glass beads were purchased from the manufacturer of Hualong mineral products, Lingshou county, at a size of 2 mm.

Examples

Example 1

The steel slag asphalt concrete is prepared from mineral aggregate, asphalt and a viscosity additive, wherein the weight ratio of the mineral aggregate to the asphalt is 4.5%, the viscosity additive is added according to the total weight of the mineral aggregate and the asphalt, and the mixing amount of the viscosity additive is 0.4% of the total weight of the mineral aggregate and the asphalt.

The mineral aggregate is prepared by mixing the following raw materials: 330g of coarse steel slag with the grain diameter of 10mm, 505g of fine steel slag with the grain diameter of 5mm, 115g of limestone with the grain diameter of 5mm and 50g of mineral powder.

The steel slag asphalt concrete is prepared by the following method:

s1, accurately weighing the coarse steel slag, the fine steel slag and the limestone according to the actual proportion, mixing and uniformly stirring to obtain primary aggregate;

s2, heating the primary aggregate to 185 ℃, adding the viscosity additive, and uniformly stirring to obtain a primary mixture;

s3, preheating the asphalt to 160 ℃, then putting the asphalt into the primary mixture, and uniformly stirring to obtain the steel slag asphalt concrete.

Example 2

The steel slag asphalt concrete is prepared from mineral aggregate, asphalt and a viscosity additive, wherein the weight ratio of the mineral aggregate to the asphalt is 4.5%, the viscosity additive is added according to the total weight of the mineral aggregate and the asphalt, and the mixing amount of the viscosity additive is 0.4% of the total weight of the mineral aggregate and the asphalt.

The mineral aggregate is prepared by mixing the following raw materials: 345g of coarse steel slag with the grain diameter of 10mm, 490g of fine steel slag with the grain diameter of 5mm, 115g of limestone with the grain diameter of 5mm and 50g of mineral powder.

The steel slag asphalt concrete is prepared by the following method:

s1, accurately weighing the coarse steel slag, the fine steel slag and the limestone according to the actual proportion, mixing and uniformly stirring to obtain primary aggregate;

s2, heating the primary aggregate to 190 ℃, adding the viscosity additive, and uniformly stirring to obtain a primary mixture;

s3, preheating the asphalt to 160 ℃, then putting the asphalt into the primary mixture, and uniformly stirring to obtain the steel slag asphalt concrete.

Example 3 to example 6

The steel slag asphalt concrete in the embodiments 3 to 6 is prepared by the method in the embodiment 1, and the difference is only the mixing amount of each raw material in the mineral aggregate, and the concrete is shown in the following table 1:

table 1 examples 3-6 blending amounts of respective raw materials in mineral aggregates

Wherein, the weight ratio of the mineral aggregate to the asphalt in the embodiment 5 and the embodiment 6 is 4%, and the mixing amount of the viscosity additive is 0.3% of the total weight of the mineral aggregate and the asphalt.

Example 7

This example differs from example 1 only in that the mineral aggregate is mixed from the following raw materials: 330g of coarse steel slag with the grain diameter of 10mm, 520g of fine steel slag with the grain diameter of 5mm, 110g of limestone and 40g of mineral powder.

Example 8

This example differs from example 7 only in that the mineral aggregate is mixed from the following raw materials: 330g of coarse steel slag with the grain diameter of 10mm, 520g of fine steel slag with the grain diameter of 5mm, 55g of limestone with the grain diameter of 10mm, 55g of limestone with the grain diameter of 15mm and 40g of mineral powder.

Example 9

This example differs from example 1 only in that the mineral aggregate is mixed from the following raw materials: 330g of coarse steel slag with the particle size of 15mm, 505g of fine steel slag with the particle size of 10mm, 115g of limestone with the particle size of 5mm and 50g of mineral powder.

Example 10

The steel slag asphalt concrete is prepared from mineral aggregate, asphalt and a viscosity additive, wherein the weight ratio of the mineral aggregate to the asphalt is 4.5%, the viscosity additive is added according to the total weight of the mineral aggregate and the asphalt, and the mixing amount of the viscosity additive is 0.4% of the total weight of the mineral aggregate and the asphalt.

The mineral aggregate is prepared by mixing the following raw materials: 330g of coarse steel slag with the grain diameter of 15mm, 505g of fine steel slag with the grain diameter of 10mm, 115g of limestone with the grain diameter of 5mm, 48g of mineral powder and 2g of reinforcing filler.

The reinforcing filler is composed of glass fiber and glass beads in a weight ratio of 1: 1.

The steel slag asphalt concrete is prepared by the following method:

s1, accurately weighing coarse steel slag, fine steel slag, limestone and reinforcing filler according to the actual proportion, mixing and uniformly stirring to obtain primary aggregate;

s2, heating the primary aggregate to 185 ℃, adding the viscosity additive, and uniformly stirring to obtain a primary mixture;

s3, preheating the asphalt to 160 ℃, then putting the asphalt into the primary mixture, and uniformly stirring to obtain the steel slag asphalt concrete.

Example 11

The present example differs from example 10 only in that the mineral aggregate is mixed from the following raw materials: 330g of coarse steel slag with the particle size of 15mm, 505g of fine steel slag with the particle size of 10mm, 115g of limestone with the particle size of 5mm, 46g of mineral powder and 4g of reinforcing filler.

Example 12

The present example differs from example 10 only in that the mineral aggregate is mixed from the following raw materials: 330g of coarse steel slag with the particle size of 15mm, 505g of fine steel slag with the particle size of 10mm, 115g of limestone with the particle size of 5mm, 44g of mineral powder and 6g of reinforcing filler.

Example 13

This example differs from example 10 only in that the reinforcing filler consists of glass fibers and glass microspheres in a weight ratio of 1: 1.5.

Example 14

This example differs from example 10 only in that the reinforcing filler consists of glass fibers and glass microspheres in a weight ratio of 1: 2.

Example 15

This example differs from example 10 only in that the reinforcing filler consists of glass fibers and glass microspheres in a weight ratio of 1: 3.

Comparative example

Comparative example 1

The comparative example differs from example 1 only in that the fine steel slag is replaced with an equal amount of coarse steel slag.

Comparative example 2

The comparative example differs from example 1 only in that the coarse steel slag is replaced by an equal amount of fine steel slag.

Comparative example 3

The comparative example is different from example 1 only in that the amount of coarse steel slag incorporated in the mineral aggregate was 300g and the amount of fine steel slag incorporated therein was 550 g.

Comparative example 4

The comparative example differs from example 10 only in that the amount of reinforcing filler is 10g and the amount of mineral powder is 40 g.

Performance test

1. Marshall stability test and Water stability test

The test is carried out according to JTG E20-2011 'test procedure for road engineering asphalt and asphalt mixture', steel slag asphalt concrete in each embodiment and each proportion is respectively taken, a Marshall test piece is manufactured by a compaction method, two sides of the test piece are compacted 50 times respectively, the forming temperature of the test piece is 160 ℃, the test piece is cooled to room temperature and demoulded after being formed, the diameter of 2 directions and 4 heights of cross symmetry directions are measured, the volume and the void ratio of the test piece are calculated, and the test piece is placed in a constant temperature water bath at 60 ℃ for 30min to carry out the Marshall stability test after meeting the requirements.

And then placing the Marshall test piece in a constant temperature water bath at 60 ℃ for 48h to carry out a water stability test, and then testing the water erosion resistance stability of the steel slag asphalt concrete.

2. Swelling capacity test

Taking the steel slag asphalt concrete in each example and each proportion to respectively prepare 3 Marshall test pieces, respectively measuring the diameter in 3 directions and the 4 heights in the cross symmetry direction, calculating the volume of the test piece, soaking the Marshall test piece in a constant-temperature water bath at 60 ℃ for 72 hours, taking out the test piece, cooling to room temperature, measuring the volume of the test piece according to the same method, calculating the expansion amount, and taking the average value, wherein the expansion amount is = (final volume/initial volume) = 100%.

TABLE 2 test results of test 1 and test 2

As can be seen from table 2, compared with the comparative examples 1 and 2 in which only coarse steel slag or fine steel slag is used, the steel slag asphalt concrete prepared by compounding coarse steel slag and fine steel slag in examples 1 to 7 has better stability and water stability, and has lower expansion amount, which indicates that the fine steel slag filled in the gap formed between the coarse steel slag can effectively enhance the stability of the steel slag asphalt concrete, and simultaneously, the water stability and the water erosion resistance of the steel slag asphalt concrete can be improved by virtue of the adhesion between the fine steel slag and the asphalt.

Compared with the steel slag asphalt concrete in the embodiment 1, the steel slag asphalt concrete in the embodiment 8 has better stability and water stability, which shows that the limestone is compounded in the steel slag asphalt concrete according to different specifications, so that the limestone can be promoted to be uniformly filled in a steel slag asphalt concrete system, and the overall stability of the steel slag asphalt concrete can be effectively enhanced.

The steel slag asphalt concrete in the embodiments 10 to 12 has better stability and water erosion resistance than the steel slag asphalt concrete in the embodiment 1, which shows that the network structure formed by the glass fiber in the asphalt can enhance the coating of the asphalt on the mineral aggregate, reduce the possibility that the mineral aggregate in the steel slag asphalt concrete is separated from the asphalt or from each other, and simultaneously improve the overall stability of the steel slag asphalt concrete. The glass beads can achieve a synergistic effect with the glass fibers, and the overall stability and strength of the steel slag asphalt concrete are enhanced together.

Example 16

A steel slag asphalt concrete pavement is paved by the steel slag asphalt concrete in the embodiment 1, and the concrete construction method of the steel slag asphalt concrete pavement comprises the following steps:

in the specific paving process, the temperature of the mixture is within the range of 185 ℃ of 170-;

after paving is finished, when the temperature of the road surface is not lower than 160 ℃, primary rolling is immediately started, and when the primary rolling is carried out, the temperature of the road surface is 165 ℃, so that the possibility that the rolling effect is influenced due to too fast temperature reduction of the steel slag asphalt concrete after paving is finished is reduced. Specifically, rolling is carried out by using a steel cylinder type road roller, the rolling speed is 6-10km/h, the rolling is carried out for 3-4 times, and the rolling speed and the number of times of the rolling can be selected according to actual conditions;

after the primary rolling is finished, secondary rolling can be performed when the temperature of the road surface is reduced to 90-95 ℃, the temperature of the road surface is 90 ℃ when the secondary rolling is performed in the embodiment, so that the possibility that the bonding material is generated due to overhigh temperature of the road surface or the compaction effect is influenced due to overlow temperature to generate gaps between the mixed materials is reduced, and the stability of the road surface and the higher bearing strength of the road surface can be ensured to a certain extent. Specifically, rolling is carried out by 1 round trip of an 8t tyre roller; the edge part of the road surface can be subjected to supplementary rolling by a small vibratory roller;

after rolling is finished, vehicles can be allowed to pass when the temperature of the road surface is reduced to below 50 ℃.

The construction method described in this embodiment is used for a field compactness test, specifically, a paving area with an appropriate size is selected, the compactness and the water seepage effect of the road surface are measured according to JTG E60-2008 'highway subgrade road surface field test procedure' after paving is completed, 3 core samples are taken during sampling, and the results are averaged. Meanwhile, a comparison example 1 and a comparison example 2 are provided, and the comparison example 1 is different from the embodiment only in that after paving is completed, primary rolling is started when the temperature of the pavement is reduced to 150 ℃; the comparative example 2 is different from the present example only in that the secondary rolling is started after the temperature of the road surface is reduced to 80 ℃ after the primary rolling is completed.

TABLE 3 compaction and Water penetration test results

As can be seen from table 3, when the construction method of the embodiment is used for paving a pavement, the pavement can have a better compactness, so as to have better stability and bearing performance, and at the same time, have better water permeability. It can be seen from the data of comparative examples 1 and 2 that the primary rolling or the secondary rolling is performed when the road surface temperature is low, which easily causes gaps between the mixed materials, so that the road surfaces of comparative examples 1 and 2 show good water permeability.

However, gaps between the mixed materials are easy to cause insufficient adhesion between the raw materials in the mixed materials, the compactness does not meet the technical requirement, and the overall stability and the bearing performance of the pavement are affected in the actual use process. Therefore, considering the use performance of the comprehensive pavement, it is better to have better water permeability while meeting the technical requirement of compactness, that is, the pavement is laid according to the construction method of the embodiment, and the temperature of the pavement during rolling is controlled to ensure that the pavement has certain compactness and also has better water permeability.

Example 17

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 2 is used for paving the road surface.

Example 18

The present example is different from example 16 only in that the concrete of the steel slag amount in example 3 is used for paving the road surface.

Example 19

The present embodiment is different from embodiment 16 only in that the present embodiment uses the steel slag concrete of embodiment 4 to pave the road surface.

Example 20

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 5 is used for paving the road surface.

Example 21

The present embodiment is different from embodiment 16 only in that the present embodiment uses the steel slag concrete of embodiment 6 to pave the road surface.

Example 22

The present example is different from example 16 only in that the present example uses the steel slag concrete of example 7 for paving.

Example 23

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 8 is used for paving the road surface.

Example 24

The present embodiment is different from embodiment 16 only in that the present embodiment uses the steel slag concrete of embodiment 9 to pave the road surface.

Example 25

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 10 is used for paving the road surface.

Example 26

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 11 is used for paving the road surface.

Example 27

The present embodiment is different from embodiment 16 only in that the concrete of the steel slag amount in embodiment 12 is used for paving the road surface.

Example 28

The present example is different from example 16 only in that the concrete of the steel slag amount in example 13 is used for paving the road surface.

Example 29

The present example is different from example 16 only in that the concrete of the steel slag amount in example 14 is used for paving the road surface.

Example 30

The present example is different from example 16 only in that the concrete of the steel slag amount in example 15 is used for paving the road surface.

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.