KR100983344B1 - Asphalt concrete using asphalt foaming property and manufacturing method thereof - Google Patents

Abstract

PURPOSE: An asphalt concrete using the foaming property of asphalt and a method for manufacturing the same are provided to reduce the amount of discharged air pollutants and the amount of used fuel by remarkably reducing a process temperature using the foaming property of the asphalt and to improve the durability of the asphalt concrete. CONSTITUTION: A method for manufacturing asphalt concrete using the foaming property of asphalt comprises a step of generating bubbles by spraying water to heated asphalt at a high pressure, a step of mixing heated aggregates, and a step of mixing a polymer modifying additive, filler, or recycled aggregates. In the step of generating bubbles, 0.1 parts by weight of the water is sprayed to 5 parts by weight of the asphalt which is heated at 150°C based on 100.0 parts by weight of the asphalt concrete.

Description

Asphalt Concrete Using Asphalt Foaming Property And Manufacturing Method Thereof}

The present invention relates to asphalt concrete mainly used for road pavement called ascon, and significantly reduces the production temperature using asphalt foam, thereby reducing the air pollutant emissions and fuel consumption, and improving the asphalt foam characteristics for construction and durability. It relates to asphalt concrete used and a method of manufacturing the same.

Conventional ascon (hereinafter referred to as 'asphalt concrete'), which is mainly used for road pavement, etc., heats asphalt and aggregate to about 160 ° C. and 200 ° C., respectively, and heats the heated asphalt and aggregate to a weight ratio of about 5:95. It is prepared by mixing in proportion.

At this time, the production temperature of the resulting asphalt concrete mixture reaches a high temperature of about 165 ℃.

In the conventional high temperature asphalt concrete manufacturing process as described above, carbon dioxide generated in the combustion process of heavy oil is consumed because a large amount of so-called 'bunker C oil', called 'bunker C oil', is used to produce 1 ton of asphalt concrete. Excessive generation of (CO2) and air pollutants (sulfur oxides: SOx, nitrates: NOx, dust).

In addition, small-scale construction such as underground burial works and construction in cold regions have a long waiting time after the production of asphalt concrete, respectively, and a rapid cooling rate of the asphalt concrete after the installation of asphalt concrete.

Such a long waiting time and a fast cooling rate cause a rise in the viscosity of asphalt concrete, which is difficult to compact. This results in an unexpectedly high pore volume at the time of design.

Due to the high porosity of asphalt concrete after installation, moisture infiltrates into the pavement in rainy weather, and moisture infiltration causes peeling of asphalt and aggregates, cracking of the pavement, and breakage of potholes.

In conclusion, the conventional asphalt concrete is excessive in the use of heavy oil as a fuel due to the high temperature production temperature required, which results in the discharge of a large amount of air pollutants. In addition, due to the above-described construction problems, the durability of the asphalt concrete is lowered, so that the maintenance is difficult and prematurely damaged during the design period.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the related art.

Its purpose is to deal with asphalt concrete mainly used for road pavement called ascon, and to reduce air pollutant emissions and fuel consumption by using asphalt foam to reduce the production temperature, and to improve asphalt foam characteristics to improve workability and durability. The present invention provides an asphalt concrete and a method of manufacturing the same.

In order to solve the above technical problem, the present invention is asphalt concrete,

(a) an asphalt foam generation step 100 of spraying water on the heated asphalt in a high pressure particle state to generate asphalt bubbles; And, (b) an aggregate mixing step (200) for mixing by adding heated aggregate after the asphalt foam generation step (100); and further, (c) the aggregate mixing step (200). ) During the process, the admixture input step (300) of mixing any one or more of the polymer modifier, filler and circulating aggregate is mixed; reducing air pollutant emissions and fuel consumption, improving construction properties and durability, further comprising: It provides an asphalt concrete using the asphalt foam properties for and the production method thereof.

According to the present invention, the following effects are expected.

First, it provides an asphalt concrete and a method of manufacturing the same using asphalt foam properties that can be produced at a lower temperature than conventional ones using the foam properties of asphalt.

Secondly, the present invention provides asphalt concrete and a method of manufacturing the same using asphalt foam characteristics of using less fuel and generating less carbon dioxide and air pollutants.

Third, it improves the transport distance of asphalt concrete due to less viscosity change due to temperature decrease than before, and provides asphalt concrete and its manufacturing method using asphalt foam characteristics that maintain predetermined construction quality even in construction in winter and cold regions. .

Fourth, because the durability is maintained after the installation of asphalt concrete, there is less risk of damage in the long term, provides easy maintenance and economical asphalt concrete using asphalt foam properties and provides a method of manufacturing the same.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 and 2 are a flow chart and a conceptual diagram showing a method for producing asphalt concrete using asphalt foam properties of the present invention, respectively.

Asphalt concrete using the asphalt foam properties of the present invention and its manufacturing method in the asphalt concrete manufacturing method,

(a) an asphalt foam generation step 100 of spraying water on the heated asphalt in a high pressure particle state to generate asphalt bubbles; And, (b) an aggregate mixing step 200 of mixing by adding heated aggregate after the asphalt foam generation step 100.

In addition, (c) the admixture input step 300 of mixing any one or more of the polymer modifier, filler and circulating aggregate during the process of mixing the aggregate (200); characterized in that it further comprises .

The (a) asphalt foam generation step 100 refers to the step of generating asphalt foam by spraying water on the heated asphalt in the form of high pressure particles. In a more specific preferred embodiment, 0.1 parts by weight of water at room temperature is sprayed at a pressure of about 2 to 6 kgf / cm 2 on asphalt having 5 parts by weight heated to about 150 ° C. with respect to 100 parts by weight of asphalt concrete. At this time, the asphalt and the water sprayed at a high pressure to make a temporary combination to maintain a foam form of about 130 ℃ about 3 minutes, which is called asphalt foam. The asphalt foam increases the unit volume and ensures fluidity than conventional asphalt. Therefore, in the aggregate mixing step 200 to be described later, the asphalt easily coats the surface of the aggregate.

The (b) aggregate mixing step 200 refers to a step of injecting the heated aggregate after the asphalt foam step 100. In a more specific preferred embodiment, the aggregate heated to about 160 ° C is about 19 to 20 times the weight of the asphalt.

Conventionally, the input aggregate was heated to about 200 degreeC or more. This is because the bonding force with asphalt decreases when it heats below 200 degreeC.

However, in the present invention, since the foam property of the asphalt is used, the asphalt having the fluidity is easily coated on the surface of the aggregate even when the aggregate is heated to a lower temperature than before.

Therefore, asphalt and aggregate mixtures can be manufactured at a manufacturing temperature of about 130 ° C., which is about 30 ° C. lower than conventional ones. As a result, about 30 ° C. lower than about 30 ° C., which is about 30 ° C. As it is constructed at ℃, it is safe and workable.

The (c) admixture input step 300 refers to the step of mixing any one or more of the polymer modifier, filler and circulating aggregate during the aggregate mixing step 200. More specifically, the polymer modifier in the (c) admixture input step (300) is a process oil of 20 to 30 parts by weight with respect to 100 parts by weight of the polymer modifier additive, 65 ~ 78 having a penetration of 80 ~ 100 It is composed of a mixture of parts by weight of asphalt, 1 to 4 parts by weight of high temperature viscosity regulator, 0.3 to 0.9 parts by weight of heat-resistant stabilizer and 0.1 to 0.7 parts by weight of compatibilizer, the filler is a mineral filler, fly ash, bottom ash, Portland cement, The silica-based spent catalyst, blast furnace slag or the like is composed of 1 to 5 parts by weight of any one or more mixed inorganic materials.

In addition, the (c) admixture in the admixture input step 300 may be composed of 0.05 to 0.25 parts by weight based on 100 parts by weight of asphalt concrete. Most preferably, the polymer modifier is 0.175 parts by weight based on 100 parts by weight of asphalt concrete. When the polymer modifier is used in an amount of 0.25 parts by weight or more based on 100 parts by weight of the asphalt concrete, homogeneous mixing with the asphalt is not performed and causes a cost increase, thereby significantly reducing workability and economic efficiency.

In addition, the (c) admixture input step (300) to the filler, mineral filler, fly ash, bottom ash, portland cement, silica-based waste catalyst, blast furnace slag, etc., any one or any one or more mixed inorganic materials 1 When used at ˜5 parts by weight, the adhesion between asphalt and aggregates is increased. As a result, the density of the entire asphalt concrete is increased, and the penetration of moisture, such as rainwater, before and after fabrication and construction is significantly reduced, the peeling phenomenon of aggregates, etc. is significantly reduced, and the overall durability is increased.

Hereinafter, the effect will be described through specific experiments.

[Table 1] shows the 'standard formulation of the asphalt mixture for the surface layer and the intermediate layer', the particle size of the asphalt concrete mixture in the asphalt concrete using the asphalt foam properties of the present invention according to the standards of the Korea Industrial Standard KS F2349 Table 1 WC A -1 compactness 13 mm mixture was prepared and compared to evaluate physical properties such as (1) plastic deformation resistance, (2) crack resistance, and (3) peel resistance.

Of mixture
Kinds
Sieve
size Assembly diagram
asphalt
concrete
20 Wheat mouth dildo
asphalt
concrete
(20) (13) Three takes dildo
asphalt
concrete
(13) Wheat mouth dildo
Gap asphalt
concrete
(13) Wheat mouth dildo
asphalt
concrete
(20F) (13F) barrel
and
rate
back
minute
rate
(%) 25 mm
20 mm
13 mm
5 mm
2.5mm
0.6mm
0.3mm
0.15mm
0.08mm 100
95-100
70-90
35-55
20-35
11-23
5-16
4-12
2 ~ 7 100
95-100
75-90
45-65 -
100
95-100
55-70 -
100
95-100
65-80
50-65
25-40
12-27
8-20
4-10 -
100
95-100
35-55
30-45
20-40
15-30
5-15
4-10 100
95-100
75-95 -
100
95-100 52-72
40-60
25-45
16-33
8-21
6 ~ 11 35-50
18-30
10-21
6-16
4 ~ 8 Asphalt amount (%) 4.5-6.0 4.5 ~ 7.0 6.0-8.0 4.5 ~ 6.5 6.0-8.0

(1) plastic deformation resistance

The plastic deformation resistance was 7.0kgf / cm2 in the asphalt concrete specimens of 100mm diameter and 75mm thickness at high temperature of asphalt compatibility grade (64 ℃ applied in the present invention) according to APA test method (AASHTO TP 63-03). When the rubber hose with grounds is grounded and the steel circumference 8000 passes horizontally through the rubber hose with a ground pressure of 73.0kg, the depth of plastic deformation generated in the asphalt concrete specimen is measured. In this case, the lower the depth of plastic deformation, the higher the plastic deformation resistance.

(2) crack resistance

The crack resistance was measured according to the method of Korean Industrial Standard KS F 2382 to measure the indirect tensile strength. Indirect tensile strength is 101.6mm in diameter and 63.5mm in thickness. The vertical load is 50mm / min in the vertical load in the direction parallel to the diameter of asphalt concrete specimen. Indirect tensile strength is calculated using Equation 1 by measuring the load having the maximum vertical load and using the thickness and diameter of the specimen. In general, asphalt concrete mixtures with high indirect tensile strength mean high crack resistance.

ST: Indirect Tensile Strength (MPa)

P: Maximum load (N)

D: diameter of specimen (mm)

h: thickness of specimen (mm)

(3) Peel Resistance

Peeling phenomenon is a phenomenon in which water penetrates into the asphalt concrete mixture, which loses the binding strength between the aggregate and asphalt, and leaves the aggregate from the mixture. Peel resistance was measured according to the method of the American Test Standard ASTM D4867 to measure the peel resistance. This test divides three specimens of 101.6 mm diameter and 63.5 mm thickness into two groups. The specimens of group 1 were subjected to the indirect tensile strength test after saturation with water by applying a vacuum pressure of 660 mmHg in water for 30 minutes, and the specimens of group 2 were subjected to the indirect tensile strength test in the same way as the indirect tensile strength test above. It was.

The residual tensile strength, which is a measure of peel resistance, is calculated using [Equation 2]. Asphalt concrete mixture with high residual tensile strength ratio is less damaged by water, which means higher peeling resistance.

Experimental Example

According to the nominal dimensions of each body, the percentage of the weight passed is 100 parts by weight for a 20 mm sieve, 95 parts by weight for a 13 mm sieve, 83 parts by weight for a 10 mm sieve, 59 parts for a 5 mm sieve, and 43 parts by weight for a 2.5 mm sieve. The particle size of the aggregate was used to have 22 parts by weight of 0.6 mm sieve, 13 parts by weight of 0.3 mm sieve, 9 parts by weight of 0.15 mm sieve, and 6 parts by weight of 0.08 mm sieve. The optimum asphalt content was calculated as 5.8% by Marshall Marshall design. Filler was added 3 parts by weight of fly ash to the aggregate. [Table 2] shows the properties of the fillers and the test results for them as defined in Korean Industrial Standard KS F 3501.

Test Items Test result Mouth dildo
(%) 0.6 mm (100%) 100 0.3 mm (95% or more) 99.2 0.15 mm (more than 90%) 93 0.075 mm (more than 70%) 78 Water content (1.0% or less) 0.2 importance 1.99 Plasticity Index (6 or less) NP Flow test (less than 50%) 40 Immersion Expansion (less than 3%) 0.9 Peel Resistance (1/4 or Less) 1/4 or less

By adding a polymer modifier to the asphalt having a common grade of 64-22 and neutralizing the asphalt having a common grade of PG76-22 using a bubble generator, the asphalt concrete using the asphalt foam characteristics of the present invention is 30 It was prepared at 135 ° C as low as 0 ° C. The experimental results for the prepared mixture are shown in [Table 3].

Comparative Example 1

Polymer modified asphalt concrete was prepared using polymer modified asphalt with the same material and the same compounding ratio as the asphalt concrete mixture using the asphalt foaming property of the present invention prepared in Test 1, but without the asphalt foaming device in a conventional general manner. Prepared. The experimental results for the prepared mixture are shown in [Table 3].

Comparative Example 2

The same material as the asphalt concrete mixture prepared in the above experimental example was prepared in the usual manner using general asphalt (penetration grade 60-80, common grade PG64-22) at the same mixing ratio. The experimental results for the prepared mixture are shown in [Table 3].

Test Items Test Methods Experimental Example Comparative Example 1 Comparative Example 2 Reference value Plastic deformation depth (mm) AASHTO TP63-03 4.35 5.14 8.06 Up to 9.0 Indirect tensile strength (MPa) KS F 2382 143 155 106 - Residual tensile strength ratio ASTM D4867 0.91 0.93 0.84 0.7

As shown in Table 3, the asphalt concrete using the asphalt foam properties of the present invention satisfies a predetermined commonness criteria. In addition, when the temperature is lowered using the bubble generator, the plastic deformation resistance is increased as compared with the polymer-modified asphalt concrete produced by the general method.

Therefore, it is possible to produce asphalt concrete mixtures having high plastic deformation resistance at a temperature about 30 ° C. lower than conventional modified asphalt concrete. In addition, it can be confirmed that when the modified additive is used, all (1) plastic deformation resistance, (2) crack resistance, and (3) peeling resistance are improved as compared with the general asphalt concrete without using the modified additive. have.

Asphalt concrete of the present invention and its manufacturing method can be produced at a lower temperature than conventional by using the foam characteristics of the asphalt, less use of fuel and less generation of carbon dioxide and air pollutants.

In addition, it improves the transport distance of asphalt concrete due to less viscosity change due to temperature decrease than before, and maintains predetermined construction quality even during construction in winter and cold regions, and maintains durability after laying asphalt concrete. It is easy to maintain and economical.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

Therefore, the claims of the present invention include modifications and variations that fall within the true scope of the invention.

1 is a flowchart illustrating a method for manufacturing asphalt concrete using asphalt foam characteristics of the present invention.

2 is a conceptual diagram illustrating a method for producing asphalt concrete using asphalt foam characteristics of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: asphalt foam generation step

200: Aggregate mixing stage

300: admixture loading step

Claims (9)

delete delete In asphalt concrete manufacturing method, (a) an asphalt foam generation step 100 of spraying water on the heated asphalt in a high pressure particle state to generate asphalt bubbles; And, (b) an aggregate mixing step 200 of mixing by adding heated aggregate after the asphalt foam generation step 100; (c) a mixed material input step (300) of mixing any one or more of the polymer modifier, filler and circulating aggregate during the aggregate mixing step (200); The (a) asphalt foam generation step 100 is heated to 150 ℃ with respect to 100 parts by weight of asphalt concrete and spraying 0.1 parts by weight of water at a pressure of 2 ~ 6kgf / ㎠ at room temperature on the asphalt having 5 parts by weight, (b ) Aggregate mixing step 200 is an asphalt concrete production method using the asphalt foam characteristics, characterized in that the input of the aggregate heated to 160 ℃. 4. The method of claim 3, In the (c) admixture input step 300, the polymer modifier is 20 to 30 parts by weight of process oil, 100 to 65 parts by weight of asphalt having a penetration of 80 to 100 with respect to 100 parts by weight of the polymer modifier, 1 to 4 It is composed of a mixture of parts by weight of high temperature viscosity regulator, 0.3 ~ 0.9 parts by weight of heat-resistant stabilizer and 0.1 ~ 0.7 parts by weight of compatibilizer, the filler is mineral filler, fly ash, bottom ash, portland cement, silica-based waste catalyst, blast furnace Asphalt concrete production method using the asphalt foam properties, characterized in that any one or any one or more of the mixed inorganic material in the slag is composed of 1 to 5 parts by weight. The method of claim 3 or 4, The (c) admixture in the admixture input step 300 is asphalt concrete manufacturing method using the asphalt foam characteristics, characterized in that consisting of 0.05 to 0.25 parts by weight based on 100 parts by weight of asphalt concrete. delete Asphalt concrete using asphalt foam properties produced by the asphalt concrete manufacturing method using the asphalt foam properties of claim 3 or 4. Asphalt concrete using the asphalt foam properties prepared by the asphalt concrete manufacturing method using the asphalt foam properties of claim 5. delete

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