JPS5858305A - Production of heated mixture for pavement - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a heating mixture for paving that uses modified asphalt as a binder containing a large amount of rubber, thermoplastic polymer, etc., with high thermal efficiency by preventing deterioration of the binder and quality deterioration. It relates to a manufacturing method.

The present inventors previously discovered that asphalt pavement in snowy and cold regions is subject to significant wear and damage due to winter spike tires, tire chains, etc., and therefore developed a new material for use in abrasion-resistant pavement that can sufficiently withstand these effects. Long-lasting repair of potholes, ruts, cracks, etc. on road surfaces regardless of warm regions, correction of differences in level between structures such as manholes and road surfaces, thin layer of wear-resistant non-slip pavement for high-grade pavements and urban pavements, etc. (Suitable for We have researched and developed heated mixtures for paving.The characteristics of these heated mixtures for paving are that they can be combined with conventionally used asphalt for paving, or asphalt modified by mixing rubber, resin, etc. with asphalt for paving. Compared to the above, modified asphalt is used, which is made by mixing large amounts of rubber, thermoplastic polymers, etc. with asphalt. The modified asphalt has excellent elasticity, caking properties, extensibility, impact resistance, etc. at low temperatures.

However, the softening point is 75°C or higher and the viscosity when melted in a heating bath is extremely high, so the temperature when producing a heated mixture for paving that uses these as a binder and the temperature at which it is used as a paving material during paving is about 200°C. Quite expensive. Furthermore, due to the high viscosity of the binder, the amount of binder in the heated mixture is also higher than in conventional mixtures.

These heated mixtures for paving have extremely good properties after paving, but the manufacturing method used in the conventional method involves melting the binder at a temperature of 30°C to make it into a liquid, then adding it to heated aggregate and mixing it. It takes a long time to melt the binder, and since the viscosity is high, it is necessary to raise the heating melting temperature, and the binder is heated at high temperature for a long time, which causes the rubber and thermoplastic polymer in the binder to polymerize. There was a risk of depolymerization and thermal deterioration of materials.

In particular, when producing υ [1 heat mixture for paving in a plant, the binder is melted in a large-capacity melting pot, which has the drawback of being recycled and continuously heated for a long time. Since the mixture must be kept at a high temperature until it is transported to the paving site and paved, there is a risk of thermal deterioration. Furthermore, the thermal energy required for heating, keeping warm, etc. is large. Depolymerization of polymeric substances due to thermal deterioration of the binder may cause the pavement to flash after being paved, since the amount of binder being mixed is large.

The purpose of the present invention is to eliminate the drawbacks of sloping, prevent thermal deterioration of the binder, reduce energy consumption, and use modified asphalt mixed with a large amount of rubber, thermoplastic polymer, etc. as the binder. The present invention provides a method for producing a paving strength [1-thermal mixture].

The method of the present invention involves molding modified asphalt, which is obtained by mixing asphalt with rubber, a thermoplastic polymer, etc., into a cut shape, plate shape, etc., into heated bones. The gist of the present invention is a method for producing a heated mixture for paving, which is characterized in that a heated mixture is produced by adding and mixing a number of additives.

The aggregate used in the present invention is coarse aggregate, fine aggregate, filler, etc. used in asphalt pavement. Crushed stone is used as the coarse aggregate, but crushed stones, gravel, slag, etc. can also be used. As fine aggregate, sand such as river sand, sea sand, mountain sand, etc. is used, but iron sand, crushed stone screening, etc. can also be used. In addition, light-colored aggregates (for example, Luxovite, Zinopal, etc.) and hard aggregates (for example, emery, silica sand, nickel slag, etc.) can be used. The filler is
Stone powder obtained by crushing limestone or igneous rocks is used, but other rock powders, carbonated lime powder, lime, gypsum, fly ash, cement, incineration ash, etc. can also be used. Further, carbon black, graphite, pigments, etc. can be used. It is also possible to use some of the fillers (asbestos, glass fiber, rock wool, synthetic wire, short fibers such as carbon fiber, mica powder, etc.).

The modified asphalt (hereinafter simply referred to as "modified asphalt"), which is obtained by mixing asphalt with rubber, thermoplastic polymer, etc. It is a modified asphalt made by Netsumachi Soushi, which is mixed with polymers (dissolved or dispersed and integrated), and has a softening point of 75 to 120°C. The amount of rubber, thermoplastic polymer, etc. in the modified asphalt is usually in the range of 8 to 35 weight percent. In addition, anti-aging agents, antioxidants, anti-foaming agents, fillers (described above), etc. may be added to the modified asphalt as appropriate.

The asphalts used in modified asphalt include straight asphalt, semi-blown asphalt, blown asphalt, blown asphalt, flopane deasphalt, rock asphalt, rake asphalt, and two or more types of asphalt. is used. Generally straight asphalt, bituminous materials such as tar and pitch may be added to these asphalts to improve their properties.

Rubbers, thermoplastic polymers, etc. used in modified asphalt include natural rubber, gutta-percha, cyclized comb,
Methyl 1/e-butadiene rubber, styrene/isoprene rubber, imprene rubber, polyisobutylene rubber, butadiene rubber, chloroprene rubber, butyl rubber, halogenated butyl rubber, chlorinated polyethylene, chlorosulfonated polyethylene, ethylene propylene rubber, EPT rubber, alphine rubber, Styrene-butadiene block polymer rubber,
Thermoplastic disease 6 -molecular polymers such as styrene/isoprene block polymer rubber, ethylene/vinyl acetate copolymer, ethylene/acrylate copolymer, polyethylene, vinyl acetate/acrylate copolymer. These are used in various shapes and forms. For example, various shapes such as powder, granular, latex, and cut-out shapes are used, and those made of new materials, recycled materials, uncured materials, and semi-vulcanized materials are used. They come in a variety of forms and types, including pulverized ones that have already been used. Examples of methods for mixing rubber, thermoplastic polymers, etc. with asphalt are as follows. Biaoyomono I is made by kneading rubber, elastomer, etc. with a rubber roll, panburi mixer, etc. (masterbatch) and melting it in a heating bath.
A method of adding C7J[I and heating and mixing. A method in which latex or emulsion is added to heated and molten bitumen, and the water is evaporated by heating and mixing. Rubber powder (e.g. powdered rubber for automobile tires), thermoplastic rubber (e.g. styrene pot butadiene block polymerized rubber, styrene/isoprene block polymerized rubber), bituminous material (C) made by heating and melting ethylene/vinyl acetate copolymer. There are methods such as adding, heating and mixing to melt and disperse.These methods can also be used in combination.

The temperature for dissolving and dispersing rubber etc. in bituminous material is 1.60-23
It is 0°C.

Along with the above rubbers, thermoplastic polymers, etc., adhesive properties,
In order to improve compatibility, thermoplastic solid resins, liquid rubbers, liquid resins, softeners, plasticizers, and the like may be added as adhesion promoters. For example, rodin and its derivatives,
Terpene resin, petroleum resin and its derivatives, alkyd resin, alkylphenol resin, terpenephenol TTL
llL Coumarone indene resin, synthetic terpene resin (for example, manufactured by Nippon Zeon, trade name Finton), alkylene resin, polyisobutylene, polybutadiene, polybutene,
Copolymers of isobutylene and butadiene (e.g. S K
Polymer 1000 (manufactured by Tonen Petrochemical, trade name), Fintol (manufactured by Nippon Zeon, trade name)), polybutene, mineral oil, process oil, pine oil, anthracene oil, pine oil, plasticizer, animal and vegetable oil, polymerized oil, etc. be. It is also possible to add anti-aging agents, antioxidants, sulfur, etc.

In addition to the modified asphalt on paper, the modified asphalt used in the present invention (C) can be used in addition to the modified asphalt on paper.

The modified asphalt used in the present invention molded into a shape such as a rice cake or a plate (hereinafter referred to as a molded modified asphalt) is the modified asphalt described above or the modified asphalt mixed with a filler. It is molded into shapes such as cut rice cakes or plates. When a filler is mixed into modified asphalt and molded, the filler becomes part of the aggregate filler of the heated mixture for pavement.

Addition of filler prevents the molded product from deforming during storage, improves the mixing of the filler and binder during the production of the υ mouth heat mixture for pavement, and facilitates the mixing of aggregate.

A molded product of modified asphalt is molded by an appropriate method when the modified asphalt is heated and molten or mixed with an appropriate amount of filler and then cooled. The shape of the molded product includes not only cut rice cake-like shapes and plate-like shapes, but also rod-like shapes, rope-like shapes, lump-like shapes, and granular shapes.

9- For molding, the molten material is poured into a plate shape or molded into a plate shape and cooled, or this is further cut or crushed. Alternatively, it is extruded using an extruder and cooled. It is possible to use the sasakaki method, which cools the particles by dropping them into a cooling liquid. These molded products are solid at room temperature, but to prevent the molded products from sticking, stone powder or a peeling sheet can be applied to the surface.

Next, a method for producing a heated mixture for paving (hereinafter simply referred to as a mixture) of the present invention will be explained.

The composition of the mixture is selected depending on the purpose of use, conditions of use, etc. The aggregate particle size is based on the particle size of a general asphalt mixture for pavement, but various other combinations can be selected as necessary.

Preferably, the mixture is prepared at or near the paving site in a mixer equipped with a heating device. It is advantageous to equip the mixer with a heating device, such as in a Kutzker car. but,
Of course, ordinary plants etc. can also be used.

Production is carried out by putting a predetermined amount of heated aggregate into a mixer, or by putting the aggregate into a mixer, heating it by force, and stirring it to form a modified asphalt molding. Divide into four or more times. Divide into at least two or more times. Normally, the heating temperature of aggregate is 180℃ to 230℃.
When a molded product of modified asphalt is added to this mixture at a temperature of approximately 30°F, it is melted by the heat of the aggregate and mixed with the aggregate. Mixing time varies depending on the blending volume of 1 batch, but 1 batch 1 ~
If it is about 2 tons, the modified asphalt molding is added in four parts and mixed for about 20 minutes, and after addition, the mixture and the binder are mixed evenly for about 5 minutes. is,
The mixtures according to the invention can be obtained and these mixtures can be immediately laid down.

In the method for producing a mixture of the present invention, heating and melting of the binder and mixing with the aggregate are performed at the same time, so the time for which the binder is heated at high temperature is greatly shortened, and it is possible to reduce the time required for the binder to be heated at a high temperature. Since there is no need to heat and melt binders other than those for quality asphalt moldings, heating the binder (by heating rubber and thermoplastics prevents thermal deterioration and depolymerization of polymers, etc.). Since there is no deterioration or deterioration in quality, it is possible to create a mixture that takes full advantage of the excellent physical properties of the rubber and thermoplastic polymer that are mixed in large quantities.

The total amount of binder in the mixture is considerably higher than that of normal asphalt heated mixture 1C, but there is no depolymerization of rubber etc. in the summer ((there is no need to worry about flashing, there is no embrittlement in the winter, so it is wear resistant, It is possible to create pavements with excellent impact resistance, slip resistance, etc.

Furthermore, the consumption of fuel required for the production of the mixture can be greatly reduced since the binding material is not heated for a long period of time and the heating, volume and aggregate mixing are simultaneously performed and shredded. etc. t
It has a unique effect.

Next, the method for producing the mixture of the present invention will be explained with reference to Examples.

Example 1 Molded product of modified asphalt: 85 parts by weight of heated, volumetric straight asphalt (penetration 60-80),
10 parts of ethylene/ethyl acrylate copolymer, 2 parts by weight of styrene/butadiene block polymer rubber, and 3 parts by weight of petroleum resin were added and mixed at 180 to 200°C for about 2 hours to form a modified asphalt with a uniform composition ( A softening point of 87°C was obtained. This modified asphal) 100 parts by weight and 2 parts limestone powder
A mixture of 0 parts by weight and 02 parts by weight of anti-explosion agent was poured into a plate shape with a thickness of about IQ 17 rust, cooled, and made into a sheet with a width of 5 cm.
Cut into 1n x length 30 rust rectangles, cover with peeling paper or polyethylene sheet, and package in a cardboard box. Use this molded product of modified asphalt by removing the peeling paper or polyethylene sheet to bind the mixture. do.

Production of mixture: Using a Kutskar truck equipped with a mixer with a heating device that has the capacity to produce 2 tons of mixture per batch, 200 kg of Silica Sand No. 6, Silica Sand No. 3 700 and 9, and 100 kg of limestone powder were put into the mixer. This is heated and mixed to a temperature of 220 to 230°C, and 200 kg of the modified asphalt molding is added and mixed over about 20 minutes, and further heated and warmed for about 5 minutes to separate the binder and aggregate. A uniformly mixed mixture at about 20° C. could be obtained. This mixture does not cause deterioration of the binder and is suitable for use in thin-layer paving (6 mm thick) on existing asphalt pavements and for level difference correction, and is used for traffic, but flashing is It has good wear resistance and slip resistance.

Example 2 Molded product of modified asphalt: 20 parts by weight of styrene-butadiene block polymer rubber was added to 70 parts by weight of straight asphalt (penetration 60 to 80) melted in a heating bath, and the mixture was heated to about 170 to 190°C. After heating and mixing to melt and mix the rubber, 10 parts by weight of automobile tire powder rubber (passed through 12 sieves) was added and heated to 170-200°C for about 1 hour to form modified asphalt (softening point 105). ℃) is obtained. After cooling this modified asphalt to a thickness of 571 m, it was cut into a rectangle with a width of 0 t7n and a length of 30 tm.
Wrap with paper or polyethylene sheet and package in a cardboard box. This molded product of modified asphalt was used as a binder for a mixture after peeling off the paper or polyethylene sheet.

Production of mixture: 6001 cg of aggregate (hard sandstone No. 7 crushed stone grains 14 - diameter 5-2.5 mm), 5001 c9 of fine aggregate (coarse river sand) and 1.001 cg of limestone powder.
, the power used in Example 1 was put into the mixer.
300 I (g) of the modified asphalt molding was added and mixed over about 20 minutes, and the binder and bone phase were mixed uniformly by heating and warming for about 5 minutes. A thin layer of this mixture was applied to wear-resistant asphalt pavement in snowy and cold regions with no deterioration of the binder and good physical properties. It has high elasticity and has very good premature wear resistance.

patent applicant 15- 21-

Claims (1)

[Claims] A predetermined amount of modified asphalt, which is obtained by mixing asphalt with rubber, thermoplastic polymer, etc., and molded into a cut shape, plate shape, etc., is added to the heated aggregate, and the mixture is heated. A method for producing a heated mixture for paving, the method comprising: