KR100998881B1 - Composition of recycled asphalt concrete - Google Patents

Abstract

PURPOSE: A recycled asphalt concrete composition is provided to prevent the environmental contamination by recycling waste asphalt concrete as recycled aggregate. CONSTITUTION: A recycled asphalt concrete composition contains the following: 100 parts of aggregate mixture by weight for a base layer or a surface layer, including 25~95wt% of waste asphalt concrete recycled aggregate and 5~75wt% of new aggregate; 0.5~6 parts of emulsified asphalt by weight; 1.5~7 parts of filler by weight; and 0.3~8 parts of emulsion-based recycle additive by weight. The emulsified asphalt is formed with 57~70 parts of asphalt by weight, 40~45 parts of water by weight, 0.3~1 parts of emulsifier by weight, 0.2~0.5 parts of potassium hydroxide by weight, and 0.2~0.5 parts of calcium chloride by weight.

Description

Recycled asphalt concrete composition

The present invention relates to a composition of recycled asphalt concrete, and more particularly, to a recycled asphalt concrete composition capable of raising the properties of the recycled asphalt concrete to the physical properties of the unreclaimed pure asphalt concrete.

In general, waste ascon, which is one of construction wastes, is classified as industrial waste and disposed of in landfill, but recently, waste ascon is recycled and used as recycled aggregate.

On the other hand, the conventional techniques for recycling the waste ascon include a technique for making recycled asphalt concrete by adding natural aggregates such as gravel, sand, emulsified asphalt and surfactant to the waste ascon.

In particular, the waste ascon can be said to be very environmentally friendly in terms of the effect of waste treatment and recycling and recycling to recycled aggregate.

On the other hand, if the prior art for the recycled asphalt concrete is presented as follows.

First, Patent Application No. 10-1997-0008030 "Additives for recycling waste ascon and repackaging method of waste ascon" discloses a method of using slurry oil by-produced in heavy oil catalytic cracking process as a recycling additive for waste ascone. have.

In addition, Patent Registration No. < RTI ID = 0.0 > 10-0898393 < / RTI > discloses the use of resin-based oil additives consisting of oils extracted from heated waste ascon and thermal decomposition products of waste vinyl resins as regeneration additives of aged asphalt.

In addition, as a foreign document, U.S. Patent No. 3,793,189 discloses deasphaltde oil, heavy distillate, and petroleum residues based on propane as a supercritical fluid separation method to improve the properties of aged asphalt. Residual Oil) and the like are disclosed, and US Patent No. 3,221,615 discloses a method of restoring physical properties of aged asphalt using coal tar derivatives. The additive is extracted from coal tar and is limited to compounds having 2 to 4 aromatic benzene rings and functional groups of alkyl compounds having phenolic and hydroxy derivatives.

In addition, US Pat. No. 4,278,469 discloses a composition in which a portion of an oil extracted from asphalt, a specific polymer and a heavy aromatic solvent are mixed as a regeneration additive for road repair and surface treatment.

However, the above-described prior arts have developed the recycled waste asphalt as recycled aggregates and the recovery of waste asphalt as properties separately, and recycle the recycled waste asphalt as recycled aggregates, while simultaneously using the recycled asphalt concretes. There was a problem that it could not be improved.

In order to solve the above problems, the present invention recycles discarded asphalt concrete, thereby saving natural resources and reducing environmental damage, and the new physical properties of the asphalt concrete produced by recycling the discarded asphalt concrete are pure. It is an object of the present invention to provide a reclaimed asphalt concrete composition comparable to the physical properties of the asphalt concrete produced by the asphalt concrete composition.

The recycled asphalt concrete composition according to the present invention for achieving the above object is 100 wt% of the base or surface aggregate formulation consisting of waste ascone recycled aggregate 25wt% ~ 95wt% and new aggregate 5wt% ~ 75wt% for road pavement 0.5 parts by weight to 6 parts by weight of the emulsified asphalt, 1.5 parts by weight to 7 parts by weight of the filler, and 0.3 parts by weight to 8 parts by weight of the emulsion-based regeneration additive.

The recycled asphalt concrete composition according to the present invention can save natural resources by recycling the waste ascon into recycled aggregate, and can suppress the unnecessary leaving of the waste ascon.

In addition, the present invention can restore the physical properties of aged asphalt by blending emulsion-based recycling additives containing high sulfur heavy oil as a main component to recycled aggregates and new aggregates, the strength, hardness, It is effective to produce recycled asphalt concrete with uniform viscosity, stability and flexibility.

In addition, the present invention has the advantage that it has an effect equivalent to pure asphalt concrete also in the road pavement and floor pavement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, the terms to be described later are defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user, the operator, and the like, the definitions of which are used throughout the present specification for describing the recycled asphalt concrete composition according to the present invention. It should be based on what has been done.

Hereinafter, the present invention will be described in detail with reference to the attached table.

The composition of the recycled asphalt concrete according to the present invention is based on 100 parts by weight of emulsified asphalt, based on 100 parts by weight of the base or surface aggregate blend consisting of 25% by weight of recycled asphalt asphalt aggregate and 95% by weight and 5% by weight of 75% by weight of new aggregate for road pavement. To 6 parts by weight, 1.5 parts by weight to 7 parts by weight of filler, and 0.3 parts by weight to 8 parts by weight of the emulsion-based regeneration additive.

In this case, the circulating aggregate means that the waste ascon crushed and used for asphalt concrete, and the mixture of the circulating aggregate and the new aggregate is suitable for the base layer or surface layer of the asphalt road through the sieving according to the notification of the Ministry of Land, Transport and Maritime Affairs. And compounding ratio.

Table 1 describes the particle size and blending ratio of the base aggregate formulation consisting of waste ascon recycled aggregate and new aggregate for road pavement.

Kinds BB-1 BB-2 BB-3

barrel
and
back
minute
rate
(%)

Size of sieve 50mm 100 - - Sieve size 40mm 95 to 100 100 - Size of the sieve 25mm 70-100 - 100 Sieve size 20mm 55 to 90 55 to 90 75-100 Sieve size 10mm 30 to 70 40 to 70 50 to 85 Sieve size 5.0mm 17 to 55 28 to 55 30 to 70 Sieve size 2.5mm 10 to 42 17-40 20-50 Size of sieve 0.6mm 5 to 28 5 to 23 5 to 25 0.3mm of sieve size 3 to 22 - - Size of sieve 0.08mm 1 to 10 1 to 7 1 to 7 Asphalt amount (%) 3.5 to 5.5

Next, to describe the particle size and the mixing ratio of the surface aggregate aggregate consisting of the waste ascon circulating aggregate and new aggregate for pavement as shown in Table 2 and Table 3.

Type of mixture
Maximum aggregate size Density Road Asphalt Concrete (20mm) (13mm) (10mm)

barrel
and
back
minute
rate
(%)

25 mm 100 - - 20 mm 95 to 100 100 - 13 mm 50 to 90 93-100 100 10 mm - - 90-100 5 mm 25 to 65 25 to 65 50 to 85 2.5mm 12-50 12-50 24 to 62 0.6mm 5 to 30 5 to 30 5 to 30 0.3mm 3 to 22 3 to 22 3 to 22 0.15mm 2 to 15 2 to 15 2 to 15 0.08mm 1 to 8 1 to 8 1 to 8 Asphalt amount (%) 4.0 to 6.0 4.5 to 6.5 4.8 to 7.0

Type of mixture
Maximum aggregate size Open road asphalt concrete (20mm) (13mm) (10mm)

barrel
and
back
minute
rate
(%)

25 mm 100 - - 20 mm 90-100 100 - 13 mm 50 to 80 90-100 100 10 mm - - 90-100 5 mm 15 to 35 15 to 45 30 to 60 2.5mm 5 to 20 5 to 20 15 to 25 0.6mm - - - 0.3mm 2 to 10 2 to 10 2 to 10 0.15mm - - - 0.08mm 0 to 5 0 to 4 0 to 4 Asphalt amount (%) 2.5 to 4.5 3.0 to 5.0 3.5 to 5.5

At this time, the asphalt amount (%) listed in Table 1, Table 2, Table 3 means the pure asphalt content contained in the emulsified asphalt, it can be calculated according to the evaporation residual test method of KS M 2203.

On the other hand, the emulsified asphalt, unlike cationic emulsified asphalt or nonionic emulsified asphalt, does not react with cement to solidify.

In addition, the emulsified asphalt can significantly reduce the cement consumption when paving the road due to low water use, and at the same time, there is no need to use expensive lignin-based additives and naphthalene-based additives.

The emulsified asphalt is based on 100 parts by weight, 57 parts by weight to 70 parts by weight of asphalt, 40 parts by weight to 45 parts by weight of water, 0.3 parts by weight to 1.0 parts by weight of emulsifier, 0.2 parts by weight to 0.5 parts by weight of potassium hydroxide (KOH). , And 0.2 parts by weight to 0.5 parts by weight of calcium chloride.

The emulsifiers included in the emulsified asphalt include carboxylates, dodecylbenzenesulfonates, alkylaryl sulfonates, higher fatty acid alkali metal salts, alkyl benzene sulfonates, alpha-olefinsulfonates, alkylarylsulfonic acid sodium salts and alkyl phosphates. , 1-nonyl-phenoxy-2-polyoxy-ethylene-3-ammonium-sulfate, sodium dioctylsulfosuccinate, and the like, and any one or more of the above-mentioned emulsifiers may be selectively used.

In addition, the test results for the properties of the emulsified asphalt are shown in Table 4 as follows.

Test results on the characteristics of emulsified asphalt Test Items Reference value Test value Particle charge Well(-) Well(-) Viscosity (@ 25 ℃, Engler degree) 3 to 40 4.76 Sieve tailings (1,190㎛) 0.3 or less 0.01 Evaporation residue (wt%) 57 or more 57.2 Residue Penetration degree (1 / 10mm) 60 to 200 76 Softening point (℃) - - Acidity (PH) 6 to 8 7.50
Storage stability

Polymer Separation Phenomenon [Height (mm) / Upper and Lower Ratio (%)] 1 day past - - 2 days - - 3 days passed - - Storage stability (1 day) 1 or less 0.7

On the other hand, the filling material may be made of any one or more of cement, fly ash, lime powder, limestone, and steelmaking dust, the particle size of the filling material is shown in Table 5.

      Particle size of filler Sieve size 600 ㎛ 300㎛ 150 μm 75 μm PAN % Pass 100 95 or more over 90 70 or more -

In addition, the quality standards of the filler material follows "KS F 3501".

Table 6 shows the quality standards for the "KS F 3501".

      Quality standard of filling material Immersion expansion Moisture content Peel Resistance Flow test Plasticity index 3% less than 1.0% or less 1/4 or less 50% less than 6 or less

Meanwhile, the emulsion-based regeneration additive is a high sulfur heavy oil emulsion emulsified with an emulsifier and is added to concrete mixtures containing waste ascon aggregate to restore the physical properties of aged asphalt and at the same time, by the sulfur component contained in the high sulfur heavy oil. By vulcanization to form a network structure can improve the physical properties of the asphalt.

An aqueous acrylic polymer may be used as the emulsion-based regeneration additive, or a reinforcing fiber may be added to the aqueous acrylic polymer.

At this time, the aqueous acrylic polymer is 100 parts by weight of MMA (Methylmethacrylate) monomer (Monomer), 100 parts by weight to 150 parts by weight of BAM (Buthylacrylate monomer), 100 parts by weight to 150 parts by weight, 0.3 parts by weight to 0.5 parts by weight of an emulsifier And, and may be composed of 0.05 parts by weight to 0.2 parts by weight of the catalyst, MMA (Methylmethacrylate) monomer (Monomer) is a material having excellent durability against various chemicals, including chlorine ions and automotive oil, in the chemical industry Since it is a well known material, a detailed description thereof will be omitted.

In addition, alkyl sulfonates, carboxylates, dodecylbenzenesulfonates, sodium resin salts, and the like may be used as emulsifiers of the aqueous acrylic polymer. In the present invention, the alkylsulfonates are used.

In addition, the catalyst composed of the aqueous acrylic polymer may be classified into a main catalyst and a subcatalyst, and as the main catalyst, ammonium persulfate may be used, and sodium bisulfite may be used as the subcatalyst.

In this case, the catalyst is preferably 30 parts by weight to 60 parts by weight of sodium bisulfite based on 100 parts by weight of ammonium persulfate.

Main properties of the emulsion-based regeneration additives presented above are shown in Table 7 below.

       Main Properties of Emulsion Regeneration Additives Lower point (℃) 230 or more Weight change rate (%) after thin film heating ± 3 or less Viscosity ratio after thin film heating (60 ℃) 2 or less Kinematic viscosity 18 to 85 (25 ° C) (SFS)

Emulsion-based regeneration additives with the above formulated ratio and physical properties can increase the Penetration No. of aging asphalt and lower the viscosity to restore adhesion to circulating aggregates or new aggregates. It is possible to lower the softening point and increase the ductility.

On the other hand, the reinforcing fiber can enhance the toughness and impact resistance, and tensile strength of the cement composite by inhibiting and stabilizing the plastic composite and dry shrinkage crack of the cement composite, improve the mechanical properties and resistance to fatigue behavior cement composite To increase the durability of the bar, as shown in Table 8 the material and physical properties of the reinforcing fiber is as follows.

      Material and Properties of Reinforcement Fiber material Polyester fiber Modulus of elasticity (MPa) 5,000 to 8,000 Tensile Strength (MPa) 400-600 Tensile Elongation (%) 30 to 40 density 1.2 or more Melting Point (℃) 240 to 260

In this case, the reinforcing material fiber should contain a certain amount of water during the manufacturing process, the moisture content can be very effective for dispersibility in the cement matrix.

In addition, the water content of the reinforcing fiber should not exceed 15% of the weight of the reinforcing fiber, and in principle, the use of 0.9kg (± 10%) per 1 ㎥ of mortar or concrete in the state containing water.

In addition, the length of the reinforcing fiber is preferably made of 1mm to 12mm.

Table 9 shows the results of the quality test of the present invention, and Table 10 shows the test report of the present invention.

      Marshall test standard and test result of base mixture Item Reference value Test result Test Methods Marshall stability (25 ℃) (N) More than 3,500 17000 KSF2337 Flow value (1/100 cm) 10 to 50 38 KSF2337 Porosity (%) 3 to 12 8.5 KSF2364

      Test Criteria and Test Results for Surface Mixtures Type of mixture
(Maximum particle diameter) Density Road Asphalt
concrete Open road asphalt
concrete result Test Methods 20 mm 13 mm 10 mm 20 mm 13 mm 10 mm Number of turns resolved (times) 50 or 70 50 or 70 50 KSF2337 Marshall stability (25 More than 5,000 More than 3,500 15000 KSF2337 Flow value (1/100 cm) 20-50 40 KSF2337 Porosity (%) 3 to 10 3 to 12 7.2 KSF2349 Saturation (%) 60 to 85 - 68 KSF2349 Indirect tensile strength
(Dry state) (25 degrees Celsius)
(Mpa) 0.15 or more 0.11 or more 1.19 KSF2382 Residual tensile strength ratio 0.75 0.65 0.87 KSF2382

As shown in Table 9 and Table 10, it can be seen that the recycled asphalt concrete composition according to the present invention has a performance suitable for quality standards.

The present invention described above is not limited to the above-described embodiments and drawings because various substitutions, modifications, and changes can be made by those skilled in the art without departing from the technical spirit of the present invention.

Claims (8)

delete For 100 parts by weight of a base or surface aggregate formulation consisting of waste ascone recycled aggregate 25wt% to 95wt% and new aggregate 5wt% to 75wt% for pavement,
0.5 parts by weight to 6 parts by weight of emulsified asphalt,
1.5 parts by weight to 7 parts by weight of filler,
And 0.3 parts by weight to 8 parts by weight of an emulsion-based regeneration additive,
The emulsified asphalt is 100 parts by weight,
57 parts by weight to 70 parts by weight of asphalt;
40 parts by weight to 45 parts by weight of water;
0.3 part by weight to 1.0 part by weight of an emulsifier;
0.2 to 0.5 parts by weight of potassium hydroxide (KOH);
And 0.2 parts by weight to 0.5 parts by weight of calcium chloride. The method of claim 2,
The emulsion-based regeneration additive uses an aqueous acrylic polymer,
The aqueous acrylic polymer is 100 parts by weight of MMA (Methylmethacrylate) monomer (Monomer),
100 ~ 150 parts by weight of BAM (Buthylacrylate monomer),
100 to 150 parts by weight of water,
0.3 to 0.5 parts by weight of an emulsifier,
Recycled asphalt concrete composition, characterized in that consisting of 0.05 to 0.2 parts by weight of the catalyst.
The method of claim 2,
The emulsion-based regeneration additive is composed of an aqueous acrylic polymer and a reinforcing fiber,
The aqueous acrylic polymer is 100 parts by weight of MMA (Methylmethacrylate) monomer (Monomer),
100 ~ 150 parts by weight of BAM (Buthylacrylate monomer),
100 to 150 parts by weight of water,
0.3 to 0.5 parts by weight of an emulsifier,
Recycled asphalt concrete composition, characterized in that consisting of 0.05 to 0.2 parts by weight of the catalyst.
The method of claim 4, wherein
The material of the reinforcing fiber is polyester fiber (Polyester Fiber),
The length of the reinforcing fiber is made of 1mm to 12mm,
The moisture content of the reinforcement fibers should not exceed 15% of the weight of the reinforcement fibers reclaimed asphalt concrete composition.
The method of claim 2,
The filler is recycled asphalt concrete composition, characterized in that any one or more of cement, fly ash, lime powder, limestone, and steelmaking dust.
The method of claim 2,
The blending ratio of the base aggregate formulation consisting of waste ascone recycled aggregate and new aggregate for road pavement has 100% passage rate in the size of 50mm sieve when the base aggregate formulation is BB-1,
In the size of the 40 mm sieve has a passage rate of 95% to 100%,
Has a pass rate of 70% to 100% in the size of the 25mm sieve,
In the size of 20mm sieve, it has a pass rate of 55 to 90%,
Have a pass rate of 30% to 70% in the size of a 10 mm sieve,
In the size of the 5.0mm sieve, it has a passage rate of 17% to 55%,
With a passage rate of 10% to 42% in the size of 2.5mm sieve,
It has a passage rate of 5% to 28% in the size of 0.6mm sieve,
In the size of 0.3 mm sieve, have a pass rate of 3% to 22%,
In the size of 0.08mm sieve, it has a passage rate of 1% to 10%,
When the base aggregate formulation is BB-2, it has a passage rate of 100% at the size of a 40 mm sieve,
In the size of 20mm sieve, 55% ~ 90% of the pass rate,
Have a passage rate of 40% to 70% in the size of 10mm sieve,
It has a passage rate of 28% to 55% in the size of 5.0mm sieve,
In the size of 2.5mm sieve has a passage rate of 17% to 40%,
It has a passage rate of 5% to 23% in the size of 0.6mm sieve,
Has a pass rate of 1% to 7% in the size of 0.08mm sieve,
When the base aggregate formulation is BB-3, it has a 100% passage rate in the size of a 25 mm sieve,
Has a pass rate of 75% to 100% in the size of the 20 mm sieve,
In the size of 10mm sieve, has a pass rate of 50% ~ 85%,
Has a pass rate of 30% to 70% in the size of 5.0mm sieve,
In the size of 2.5mm sieve has a 20% to 50% pass rate,
Have a passage rate of 5% to 25% in the size of 0.6mm sieve,
Reclaimed asphalt concrete composition, characterized in that having a passage of 1 to 7% in the size of 0.08mm sieve.
The method of claim 2,
For road pavement, the mixing ratio of the surface asphalt aggregate formulation consisting of recycled asphalt asphalt aggregates and new aggregates has a passage rate of 100% at a size of 25 mm sieve for dense asphalt concrete with a maximum aggregate size of 20 mm,
In the size of the 20mm sieve has a passage rate of 95% ~ 100%,
In the size of 13 mm sieve, 50% to 90% of the pass rate,
In the size of the 5 mm sieve, 25% to 65% of the pass rate,
Have a passage rate of 12% to 50% in the size of 2.5mm sieve,
It has a passage rate of 5% to 30% in the size of 0.6mm sieve,
In the size of 0.3 mm sieve, have a pass rate of 3% to 22%,
It has a passage rate of 2% to 15% in the size of 0.15mm sieve,
Has a pass rate of 1% to 8% in the size of 0.08mm sieve,
For landfill asphalt concrete with a maximum aggregate size of 20 mm
In the size of 25mm sieve, it has a 100% pass rate,
Have a pass rate of 90% to 100% in the size of the 20 mm sieve,
In the size of 13mm sieve, 50% ~ 80% pass rate,
Have a pass rate of 15% to 35% in the size of the 5mm sieve,
In the size of 2.5mm sieve, it has a passage rate of 5% to 20%,
In the size of 0.3mm sieve, have a passage rate of 2% to 10%,
Reclaimed asphalt concrete composition, characterized in that having a passage rate of 0% to 5% in the size of 0.08mm sieve.