JPS58204203A - Regeneration and additive composition 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 relates to a recycled additive composition for pavement of recycled asphalt mixtures intended for high-grade pavement, simple pavement, bridge surface pavement, airport pavement, etc.

In recent years, recycling of aged and unnecessary asphalt mixtures has been reconsidered due to the trend toward resource and energy conservation.

For recycling of asphalt mixtures,
Broadly speaking, there are central plant methods and on-road methods.

The central plant method is a method of recycling in a special or conventional type of plant, in which waste materials are collected in a stockyard, then loosened and classified by crushing or thermal crushing using crushing equipment, and recycled into new aggregates and straight materials. Add and mix supplementary materials such as asphalt and recycled additives.

In addition, in the on-site method, part or all of the existing asphalt mixture is cut at the site, and supplementary materials such as aggregate, straight asphalt, and recycled additives are added to the cutting waste and mixed. Then, it is leveled and compacted.

However, when a recycled asphalt mixture containing straight asphalt or recycled additives is used as an asphalt mixture for paving, compared to a general asphalt mixture, when subjected to repeated traffic such as vehicles, it causes fluid deformation and deformation on the road surface. It is difficult to maintain a flat road surface for a long period of time because it is prone to wear and tear.

The reason for this is that in the asphalt in the asphalt mixing section, which is waste material from existing pavement, the maltene fraction (refers to that consisting of n-pentane soluble polar fraction, aromatic fraction, and saturated fraction) in the asphalt. ) is oxidized or polymerized and transferred to asphaltone (n-pentane insoluble matter), resulting in a relative shortage of maltene fraction compared to the original straight asphalt in terms of chemical composition.

In addition, the physical properties of the asphalt in the aged waste asphalt mixture are observed to be lower in penetration, elongation, and higher softening point compared to the original straight asphalt.

In order to regenerate aged asphalt mixtures with such physical properties, adding a low-viscosity regeneration additive mainly composed of maltene fractions results in flow deformation phenomena at high temperatures and abrasion at low temperatures compared to new asphalt mixtures. The phenomenon becomes more likely to occur. ``Also, when adding straight asphalt for regeneration, it is necessary to add a large amount to restore the physical properties of the original straight asphalt.
As a result, as the amount of asphalt in the recycled asphalt mixture becomes excessive, there is a drawback that flashing and flowing phenomena tend to occur.

The present invention has been made to solve the above-mentioned drawbacks, and its purpose is to be able to be used in a wide range of applications regardless of the degree of aging of waste materials, and to provide recycled asphalt mixtures with durability and flow resistance. An object of the present invention is to provide a pavement recycling additive composition that can be used as a pavement.

In order to achieve the above object, the present invention provides a petroleum-based softener 1
It is characterized in that the rubber content is 1 to 30 parts by weight relative to 0.00 parts by weight.

Hereinafter, the reclaimed pavement additive composition according to the present invention will be explained. The present invention consists of the following two components: a petroleum softener and rubber.

■1 Petroleum-based softeners are distilled oil obtained by separating low-boiling fractions from crude oil using an atmospheric distillation column, and distilling the heavy crude oil remaining at the bottom of the atmospheric distillation column under reduced pressure. is the type of crude oil,
They are classified into paraffinic softeners, naphthenic softeners, and aromatic softeners depending on the treatment process and formulation, but all of these softeners can be used in the present invention.

Such a petroleum softener has a chemical composition close to that of the maltene fraction in asphalt.

2. As the rubber, various synthetic rubbers including natural rubber are used, and they may be used in a single stack or in a mixture of two or more types. Its properties are solid or latex type, and good results are obtained when the rubber has a Mooney viscosity of about 10 to 100. Examples of synthetic rubber include chloroprene rubber, styrene-isoprene copolymer rubber, and polyisoprene rubber.

Polybutadiene rubber, styrene-butadiene copolymer rubber, etc. are used.

The composition of the present invention is usually obtained as follows.

Gradually add a predetermined amount of rubber, such as rubber latex or 1 to 30 parts by weight of solid rubber, to 100 parts by weight of a petroleum softener heated and melted at a temperature of 90 to 160°C, and heat while continuing to stir. The present invention provides a reclaimed pavement additive composition.

A reclaimed asphalt mixture can be obtained by using the thus obtained material with a waste asphalt mixture in a central plant system, on-road system, or the like.

Incidentally, an anti-peeling agent or the like may be added if necessary.

Examples of the present invention will be described in detail below.

First, in the first example, 30 parts by weight of chloroprene rubber latex (calculated as solid content) was added to 100 parts by weight of a petroleum softener heated and melted at a temperature of 140 to 160°C, and stirred to remove moisture. The recycled pavement additive composition according to the present invention is obtained by removing and stirring and dissolving until uniform.

This invention is based on aged asphalt extracted from waste asphalt mixture) 100! When 15 parts by weight of the recycled pavement additive composition of the present invention is added and mixed, the properties shown in Table 1 below are obtained. 15 parts by weight of a mineral oil-based aromatic oil was added and mixed with 100 parts by weight of the extracted aged asphalt.

In the second example, 28 parts by weight of styrene-butadiene copolymer rubber latex in terms of solid content was added to 100 parts by weight of a petroleum softener heated to a temperature of 140 to 160°C, and stirred to remove moisture. The recycled pavement additive composition according to the present invention is obtained by removing and stirring and dissolving until uniform.

According to the present invention, when 16 parts by weight of the pavement recycling additive composition of the present invention is added and mixed with 100 parts by weight of aged asphalt extracted from waste asphalt, the properties shown in Table 1 below are obtained. .

In the third example, 22 parts by weight of chloroprene rubber latex in terms of solid content was added to 100 parts by weight of a petroleum softener heated to a temperature of 140 to 160°C, stirred, and water removed. By adding 5 parts by weight of block copolymer rubber (SIS type) and stirring and dissolving the mixture, a reclaimed pavement additive composition according to the present invention is obtained.

According to the present invention, when 14 parts by weight of the pavement recycling additive composition of the present invention is added and mixed with 100 parts by weight of aged asphalt extracted from waste asphalt, the properties shown in Table 1 below are obtained. .

Table 1 As mentioned above, according to the reclaimed pavement additive composition of the present invention, 1 to 3 parts of rubber is added to 100 parts of petroleum softener.
By setting the amount to 0 parts by weight, when the present invention is used as a recycling additive for waste materials, rubber and malten fraction are sufficiently added to the waste materials, and aged asphalt is restored to a state close to its original chemical composition. At the same time, it increases in viscosity and becomes highly durable and adhesive, so it exhibits extremely high resistance to flow, embrittlement, and abrasion, making it possible to form safe and smooth traffic routes.

In addition, petroleum-based softeners have a stronger ability to dissolve rubber, etc. than asphalt, have good compatibility with aged asphalt, and have low viscosity, making it possible to obtain recycled asphalt mixtures that are close to the original asphalt. At the same time, work efficiency is improved.

Furthermore, since a large amount of the present invention is not required for waste materials, recycling of waste materials is efficient and economical.

Patent applicant Toa Road Industry Co., Ltd. Agent Patent attorney Takashi Kanakura Two procedural amendments (
Mutsumi) January 2511, 1980 Kazuo Wakasugi, Commissioner of the Patent Office 1, Indication of the case 1982 Patent Application No. 068852 2, Title of the invention Recycled additive composition for pavement 3, Relationship with the amended person case Patent Applicant (84) Representative Director Kawaguchi Iwa 34
Director 7, Contents of amendment 1. Page 2, line 10 to page 3, line 19 of the specification are corrected as follows.

[The reason for adding straight asphalt and recycled additives in this way is that the asphalt in the asphalt mixture, which is waste from existing pavement, contains maltene fraction (polar fraction soluble in n-pentane, This refers to a substance consisting of an aromatic fraction and a saturated fraction. This is because the maltene fraction is relatively insufficient compared to the asphalt. Therefore, as for the physical properties of this asphalt, increases in penetration, elongation, and softening point are observed compared to the original straight asphalt.

However, in order to regenerate aged asphalt mixtures with such physical properties, when all of the above-mentioned low-viscosity regeneration additives containing mainly maltene fractions are added in the central plant system or on-road system, compared to new asphalt mixtures. As a result, flow deformation phenomena are more likely to occur at high temperatures, and abrasion phenomena are more likely to occur at low temperatures.

Furthermore, when straight asphalt is added to regenerate an aged asphalt mixture, it is necessary to add a large amount to restore the physical properties of the original straight asphalt, resulting in an excess amount of asphalt in the recycled asphalt mixture. The drawback is that flash and flow phenomena tend to occur as the temperature increases.

Therefore, it is difficult to use straight asphalt or recycled asphalt mixtures with recycled additives added as pavement asphalt mixtures.

Claims (1)

[Claims] 1. A reclaimed pavement additive composition comprising two components, a petroleum softener and rubber, and containing 1 to 30 parts by weight of rubber per 100 parts by weight of the petroleum softener.