JPS59213804A - Asphalt concrete for pavement and production thereof - 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 thermally engineered asphalt concrete I having a comparatively large Marshall stability value and a method for producing the same.

Thermal engineering asphalt concrete-1- is made by adding several types of aggregate (including filler) with different particle sizes. 'IH Goj
It is a bituminous material (mainly obtained by mixing with stred asphalt) and is extremely widely used for road paving because it is excellent in terms of second cast and performance.

And °ζ Its static strength is expressed by Marshall stability,
The bigger the base, the more intense the interaction! It is said to withstand

By the way, when the amount of dense-grained asphalt concrete, which is currently most commonly used in the surface layer, is 6 to 6.5% (wt%, Jri 1-same), the Marshall stability is the highest. , does not show an oil tightness value of 700 to 850 kg. In other words, base layer 1 [value is 750 or higher for C traffic or higher, and 50 F1 or higher for others (500 or higher for base layer, 350 or higher for two-layer roadbed.) However, for major national roads and expressways, On roads with extremely heavy traffic such as 3fi roads, dense-grained asphalt is allowed.
2R concrete lacks stability, so modified asphalt concrete mixed with rubber powder, rubber emulsion, thermoplastic 41 fat emulsion, etc. is used. However, although these exhibit high stability of 900 to 1,600 kg, they have the disadvantage of being difficult to construct and being 20 to 30% more expensive. On the other hand, asphalt concrete 1-
The proportion of asphalt in the material cost is extremely high, and in the case of standard dense-grained asphalt concrete,
As much as 0%. Moreover, as the price of crude oil rises, this ratio and the overall cost 1- are increasing. Moreover, reducing asphalt l-ff1 reduces stability by 4%.
(around 550). Therefore, the present inventors conducted research without reducing the stability and reducing the amount of asphalt, and as a result, they developed a technique to mix polyvinyl chloride powder or pieces together with an inorganic polymerization initiator for vinyl chloride. . This not only reduced the amount of asphalt and improved its stability, but also solved the problem of processing waste PVC products such as agricultural waste PVC film.

The present invention further develops this technology by mixing foamed polystyrene, which is also considered difficult to process, into an asphalt mixture together with polyvinyl chloride powder and pieces. be. First, the present inventors put pulverized polystyrene foam into a mixer together with asphalt (4% based on the amount of aggregate and asphalt) and mixed the mixture for 1'1'. However, foamed polystyrene has a very high i% iQ+, so it can only be mixed with asphalt at a rate of about 5%, and its stability is only about 650, making it one of the few. When we tried soaking expanded polystyrene in thinner and kneading it by applying mechanical impact, the volume decreased by a fraction of a minute to several fractions of a second and became putty-like. When the putty-like polystyrene was mixed with asphalt 4 (approximately 1%) as described above, it showed a stability of approximately 1,500.Additionally, to the heated mixture was added the unreleased commercial initiator used for the polyvinyl chloride. As a result, the stability reached even after 2000iiij.Nothing had ever existed that showed such commercial stability.On the other hand, when using this putty-like polystyrene and polyvinyl chloride strips with a 6:Z of about 8%, no polymerization initiator was used. showed a stability of over 2000.

Although it is not clear how this phenomenon occurs,
This is thought to be due to the fact that the putty-like polystyrene undergoes chemical, mechanical, or thermal action, resulting in a decrease in molecular weight, making it easier to disperse into asphalt I, and then being repolymerized by the action of the polymerization initiator. It will be done. However, it shows high stability even without a polymerization initiator, and when used with polyvinyl chloride (if used), it shows higher stability without a GJ city initiator, so the asphalt itself may have some effect on these resins. Being there: I can get PJ.

The material used in the present invention is firstly foamed polystyrene (foamed steel IJ-ru). Foamed polystyrene is used for various packaging cushions + A, heat insulation) A,
Or, it is widely used as a container for fish boxes, etc., but because of its bulk, the waste product stands at L1, and other than that, it is mixed into concrete and products to reduce weight and provide insulation. The current situation is that it is no longer being incinerated. In the present invention, this waste expanded polystyrene is used as it is, and resources can be used effectively. However, in the present invention, virgin materials can of course be used.

Next, as a solvent, melt J! It is best to use something with a mild ratio/bite action that softens and forms it into a putty. For example, in addition to the above-mentioned thinners, acetone, ligroin, styrene monomer, a mixture of ethylalnylene and l-recurne, i&5 or j3 and ura, etc. can be used. Then, it is preferable to further mechanically stir and knead to ensure defoaming and paralysis. When the foamed polystyrene soaked in the solvent on the lifting table is transferred to the Sufuribo 4-extruder, it is possible to form a bag at a higher rate.

At this time, it is preferable to recover the styrene monomer mixture in order to utilize the solvent, but in the case of styrene monomer, it is converted into poly-3 and -4 in the asphalt mixture.

Also, if the waste oil remains,
Since it interferes with 4'l', it is necessary to sufficiently remove it. What?
The solvent needed to make putty from polystyrene foam is thin.

- per expanded polystyrene] 0 (10,
=o, styrene monomer I O[1, approximately.

Therefore, it is preferable to use about 10 to 50% of this putty-formed Boristine I/CJ phantom asphalt. If it is mixed in at 50% or more, the asphalt mortar may become brittle, and if it is 10% or less, it will not contribute much to improving stability. More preferably, it is 30 to 45%.

Also, depending on the amount of putty-like polystyrene, great stability can be obtained as is, but peroxysulfate,
If compounds such as peroxyborate, reduced iron, 30% hydrogen peroxide, etc. are used in an amount of 0.5 to 5% relative to asphalt, the stability will further increase.This is because these compounds act as a type of polymerization initiator. It is understood that this is due to the effect of

On the other hand, a mixture of putty-like polystyrene and polyvinyl chloride powder or pieces shows an extremely high stability of 2 (100 or more) without using a polymerization initiator. -5% to 10% is preferable, especially 7% to 9%, where the stability is the highest.
4. By the way, polyvinyl chloride is extremely widely used in agricultural film wrapping, electric wires, molded products, etc., but since it contains chlorine, it cannot be easily incinerated, and its disposal poses even more problems than foamed polystyrene. However, in the present invention, there is a problem of pollution because it is only crushed and added to asphalt. be. Incidentally, in the case of polychlorinated hydrogen, virgin resin is also naturally used.

By the way, the most preferable ratio of asphalt 1 in oil-tight surface layer asphalt J concrete 1 is as follows:
As mentioned above, it is 6 to 6.5% (the smaller the amount of filler and filler, the smaller it is, and the more it is, the more pronounced it is), but in the case of the present invention, this percentage is lower. This is also a major feature. That is, the preferred ratio of asphalt in the present invention is 1, in the case of rich grain asphalt concrete I-J) ~ [1%, especially 3.5 to 5%
That's about it. This is because after 6% 1iii, asphalt is needed to cover the surface of the shrine.Since the amount of asphalt is 1, putty-like polystyrene and Jj'li vinyl can exert a significant reinforcing effect.- If the force is too small, the high/goo effect will be insufficient, resulting in brittleness and poor stability. And 3.
In the case of 5 to 5%, the stability is equivalent to or higher than that of the conventional product at 6%.

On the other hand, in the case of the base layer and roadbed (upper roadbed), the optimum proportion of asphalt l- is smaller than in the case of the surface layer because the particle size of the aggregate is large. The base layer is composed of coarse-grained asphalt concrete with an asphalt content of 4.5 to 6%. l) The disc is used as a stabilizing agent 3.
A mixture of about 5 to 4% asphalt is generally used (the stability value is 500 or more for coarse grain size - 350 or more for stable treated products). However, in the case of the present invention, a product that fully satisfies these standards can be obtained even with an asphalt content of about 2%.

The base layer and the surface layer of the II'8 board contain a large amount of Asphalt C. Reducing the amount of asphalt has an extremely large economic effect.

Next, the present invention will be explained in more detail with reference to Examples. Note that % does not indicate weight %.

Example I.

First, crush IKg of expanded polystyrene, and
Soak in 01-1 lacquer thinner (containing about 50% toluene) to soften and melt, and knead well with a spatula to form putty-like polystyrene (4.

Next, heated 5-13 (JIS /15
001 and below) crushed stone 35Kg, S-5 (crushed stone>
Put 25Kg of screening, 19Kg of sand, 5Kg of stone powder into a mixer, and mix 170'c4 Kohoge (
'CIO practice for seconds. Next, 4% of the total amount of straight asphalt heated to 170'c) and putty-like polystyrene lh <25% of the asphalt) described in 1. heating asphal)? JA compound (1).

Similarly, the amount of putty polystyrene is 33% compared to asphalt.
%, 42%. A heated asphalt mixture is obtained using 50% and 70%. Eggplant 1-
Create a piece and f! 7/The measurement results are shown in Table-1.

Example 2.

In the same dense grain formulation as in Example 1, asphalt was added at 3%, 5%, and
6%, putty-like polystyrene and 42% asphalt respectively.
A heated asphalt mixture was obtained in the same manner as in Example 1.

Example 3 A heated asphalt mixture was obtained in the same manner as in Example 1, using asphalt and putty polystyrene in the proportions shown in Table 1, and injecting a polymerization initiator into a mixer almost simultaneously with asphalt i-. The polymerization initiator used was ■3
0% hydrogen peroxide 1.5% (against asphalt), 030
% Hydrogen peroxide solution 5%, ■ Ammonium peroxysulfate 1
．． 5%, (1) ammonium peroxysulfate 1.5%, reduced iron 1.5%, (2) and 30% hydrogen peroxide solution.

Comparative Example 1゜A heated asphalt mixture was obtained in the same manner as in Example 1 except that 4% of asphalt was used in the same dense particle formulation as in Example 1.

Comparative Example A heated asphalt mixture was obtained in the same manner as in the example using 6% 2° asphalt.

Comparative example 3゜ Asphalt 5.5%, rubber emulsion (manufactured by Rohto Zeon ■, product name "Roto Suk J") against asphalt 10
A heated asphalt mixture was obtained in the same manner as in Example 1 except that % was used.

1 piece of eggplant was prepared by a conventional method from the heated asphalt mixture shown in each of the Examples and Comparative Examples, and the measurement results obtained are shown in Table 1.

Example 4゜In addition to asphalt and putty-like polystyrene, 1 to 2 mm square polyvinyl chloride H was added to the old material with the same dense grain composition as in Example 1.
A. Mix the strips of industrial waste vinyl in the proportions shown in Table 2, and heat asphalt in the same manner as in Example 1. A Ju compound is obtained.

A test piece was prepared from this heated asphalt I mixture by a conventional method, and the measurement results obtained are shown in Table 2.

Example 5: Polystyrene made into a putty using 5° dense aggregate, 4% asphalt, and waste oil (42% of asphalt).
A heated asphalt mixture is obtained in the same manner as in Example 1, with the addition of polyvinyl chloride film strips (8% based on asphalt).

In addition, (2) uses 35% hydrogen peroxide solution as a polymerization initiator at 1.5% based on asphalt, and (2) uses ammonium peroxysulfate at the same <1.5%.

Example 6 As in Example 4, asphalt, putty polystyrene, and polyvinyl chloride strips were used as binders, but the amount of asphalt was varied.

The measurement results of Examples 4 to 6 are shown in Table 2.

Example 7゜Coarse particle blend aggregate (20% S-20 crushed stone, 31% 5-13 crushed stone, 22% S-5 crushed stone, 11% S, C, 1 sand)
1%, stone powder 5%], the same straight asphalt-like polystyrene as in Example 1, and as a polymerization initiator, anti-asphalt l-
1.5% of 30% hydrogen peroxide solution is mixed in the same manner as in Example 1 to obtain a heated asphalt mixture. In addition, ■ is 3% asphalt (relative to the total amount of Kanko and asphalt), ■ is 4% asphalt, and ■ is 1 to 5% asphalt.
This is what I used. In addition to the binder (3% asphalt) and putty polystyrene (42% to asphalt), polyvinyl chloride strips (8% to asphalt) were used as binders, and the polymerization initiator was omitted.

Comparative Example 4 In the same manner as in Example 7, only asphalt was mixed in 5% of the total amount of aggregate and asphalt 1 to the coarse-grained bone H to obtain a heated asphalt 1 mixture.

Example 8゜ Aggregate mixed for upper roadbed (S-20 crushed stone 33%, 5-1
3 crushed stone 16%, S-5 crushed stone 14%, S, C 19%,
15% sand, 3% stone powder], as in Example 1, straight asphalt and putty polystyrene at 12% to asphalt, and 30% hydrogen peroxide solution to 1.5% to asphalt as a polymerization initiator. Mixing is performed in the same manner as in Example 1 to obtain a heated asphalt mixture. In addition, (■) uses 2% asphalt (relative to the total amount of aggregate and asphalt), (2) uses 3% asphalt, and (2) uses 4% asphalt. In addition, (2) used as a binder 2% of asphalt and putty-like borisdylene with a ratio of 42% to asphalt, as well as polyvinyl chloride strips at 8% to asphalt, and omitted the polymerization initiator.

Comparative Example 5゜As in Example 8, only asphalt was mixed at 4% based on the total amount of aggregate and asphalt into coarse-grained aggregate to obtain a heated asphalt mixture.

The measurement results of Example 7.8 and Comparative Example 4.5 are shown in the table below.
Shown in 3.

From the above results, it can be seen that the thermally engineered asphalt concrete of the present invention exhibits extremely excellent values in the Marshall stability test. In addition, conventional modified asphalt concrete for high stability has almost the same amount of sulfard as the standard product, but the present invention can save tens of percent and has a higher stability than previously expected. This makes an extremely large contribution to the effective use of asphalt, cost reduction, and strength improvement of asphalt concrete. On the other hand, pieces and powder of putty-like polystyrene and polyvinyl chloride, which are used as binders together with asphalt, act as MNA increasers or reinforcing materials for asphalt, but both have traditionally been difficult to dispose of as waste. It is a thing,
It is also highly effective in terms of waste treatment and effective use of resources.

Claims (1)

[Scope of Claims] 1. Asphalt concrete for pavement, characterized in that it uses putty-like polystyrene together with a bituminous material as a binder for aggregate. 2. The asphalt concrete for paving according to claim 1, which uses polyvinyl chloride powder or pieces together with putty-like polystyrene. 3. Putty-like polystyrene obtained by adding bituminous material and a solvent to preheated aggregate, defoaming and kneading, and if necessary, polyvinyl chloride powder or pieces and/or a polymerization initiator. A method for producing asphalt concrete for pavement, characterized by stirring and mixing while sequentially adding and mixing.