JP2923587B2 - Manufacturing method of elastic pavement material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an elastic pavement used for repairing bridges and roads.

[0002]

2. Description of the Related Art Conventionally, a room temperature asphalt mixture, which has been frequently used, becomes unusable because the heated asphalt mixture solidifies with cooling and becomes unusable. The viscosity of the asphalt itself is reduced with oils such as heavy oil, light oil, and volatile oil, solvents or diluents, and the mixture is adjusted so that the mixture does not solidify at room temperature.

[0003] For this reason, there are the following disadvantages. Additives such as oils are inevitable in order to keep the viscosity and fluidity of the mixture within the usable range at room temperature, so that the quality is significantly reduced. If the room-temperature mixture is compacted and rolled in a usable state, the volatilization and separation of the solvent and diluent will be significantly inhibited, and it will take a long time to obtain a high quality road surface material. During storage, oils, solvents, and volatile substances are easily separated, and cannot be stored for a long time.

[0004] Stretch pavement materials (elastic pavement materials) used for continuous pavement generally include special modified asphalt (asphalt mixed with synthetic resin, rubber, etc.) to improve the original performance of asphalt. And coarse aggregate,
It is a fine aggregate or a mixture composed of an inorganic powder, a rubber powder, or the like, and is a stretchable pavement material having properties not found in conventional asphalt pavement materials.

[0005] The modified asphalt used for the stretchable paving material needs to have elasticity and flexibility, but does not have a load-bearing capacity to support the load of a vehicle or the like. Is added to increase the load-bearing capacity against the compression pressure and at the same time secure the necessary elasticity. At room temperature, the solid or rubber-like solid melts together with the heating and exhibits fluidity.

The following method has been proposed as a method for filling and molding the stretchable pavement material into a joint portion, a stretchable portion, and a repair portion of a continuous pavement. Injection and cast molding As shown in FIG. 1, the heated aggregate is spread, and the binder that has been heated and melted is poured within a time period in which the aggregate does not decrease in temperature, and the binder is injected into the gap between the aggregates.

[0007] If the layer is thick, this step is repeated to thicken the layer. Premix injection molding The heated aggregate and the heated and melted binder are mixed in advance, and the mixture is spread. Further, the insufficient binder is injected into the aggregate gap as shown in FIG. Mixing filling molding A heated mixture in which a heated aggregate and a predetermined amount of a heated and fused binder are mixed in advance is spread (FIG. 3) .

[0008] As described above, in-situ molding of an elastic pavement material has been conventionally carried out by the following methods. However, any of the methods has the following disadvantages, and satisfactory results cannot be obtained in terms of workability and function of the molded product.

(A) In a working environment on a road where it is difficult to maintain the temperature of the aggregate and particularly easily affected by the outside temperature, it is almost impossible to adjust the temperature between the aggregate gaps to an appropriate temperature. Therefore even if injected pouring the heated binder at an appropriate temperature, it can not be expected that allowed to averagely insult fill the binder aggregate the gap is as FIG.

(B) The same difficulty as in the preceding paragraph occurs, and the temperature of the binder and the aggregate mixed by heating is lowered immediately after the spread, so that the molded product is solidified while leaving voids as shown in FIG.

(C) The binder and the aggregate are separated from each other for the following reasons, and a uniform molded product cannot be obtained. Ordinary asphalt pavement mixture has a binder ratio of 5-6%
It is. In order to satisfy this kind of elasticity function, it is necessary to increase the amount of the binder in the elastic pavement material by a considerable amount to about 15 to 20%. For this reason, the molded product undergoes phase separation due to a difference in specific gravity between the binder and the aggregate before solidification by cooling, and the aggregate sinks, as shown in FIG. 5, and a uniform molded product cannot be obtained.

(D) When the heated mixture produced in the plant is transported to the point of use, the temperature is lowered, so that the transport range is limited. Therefore, it is necessary to arrange manufacturing plants in various places and to establish a system to respond to demand.

(E) Since the temperature of the heated mixture brought into the site decreases, it is difficult to obtain a predetermined pavement layer unless it is laid and compacted for a predetermined time.

(F) If the construction has to be interrupted during transportation or on standby due to sudden rainfall, the heated mixture must be discarded, and even if reused, the cost increases compared to fresh production. Has been invited.

(G) In the case where the heating mixture is supplied during an unstable period of demand (a winter period in a cold region or a snowfall region),
It is particularly uneconomical in the case of a small amount, and in practice, the operation of the plant is often stopped.

(H) The heated mixture solidifies with cooling.
Once the heated mixture is produced, even if the temperature is prevented from lowering by a warming device or the like, the asphalt deteriorates or deteriorates, so that it is stored within several days.

From the above, as a method of obtaining a uniform molded product, even if the mixed material is sufficiently homogeneously mixed by a mixer or the like, the mixing is interrupted, or the phase separation is performed immediately after the mixed material is filled in the expansion and contraction section. start. Aggregate / binder separation
There is a disadvantage that the amount of the binder coated on the aggregate is extremely small. As for the elasticity of the elastic pavement, the elastic function cannot be exerted on the pavement unless an elastic binder having a certain thickness is secured between the aggregate particles.

From these viewpoints, it is desired to select the following method as a method for avoiding the above separation state. However, in addition to the above-mentioned problems, there is a disadvantage that only a very small-scale construction can be performed.

[0019] Such a problem is found to be caused by the fact that the aggregate and the binder tend to separate from each other due to a difference in specific gravity before the mixture heated and mixed in a predetermined mixture is cooled and solidified. The present invention is completed by focusing on the point that a predetermined amount of binder adheres while maintaining a predetermined thickness around the aggregate, and solidifies without separating if it is rapidly cooled and solidified in an appropriate amount in a very short time. did.

[0020]

The gist of the present invention will be described with reference to the accompanying drawings.

The modified asphalt-based binder and the coarse and various aggregates 7 are mixed by heating, and the heated mixture 6 is mixed with the mesh 1
To make it into a granulated state and quenching it , thereby producing a stretchable pavement material.

[0022]

[Effect of the invention and the effect of the present invention, the modified asphalt system
The binder and various coarse and fine aggregates 7 are mixed by heating.
The heating mixture 6 is passed through the mesh 1 to obtain a granulated state.
When this is quenched, the binder is almost uniformly
At the room temperature.
A loose granular pavement material that does not wear is obtained. Ma
When this granular mixture is heated, a binder layer on the surface is formed.
Pavement with excellent elasticity if softened and pressurized in this state
A body will be formed.

As described above, a granular material suitable for forming a pavement
Can be mass-produced easily and cost-effectively
This is a method for producing a stretchable pavement material exhibiting the effect of (1).

[0024]

EXAMPLE A modified asphalt-based binder in which asphalt is blended with a synthetic resin, rubber, etc. to improve the original performance of asphalt, and various aggregates such as coarse aggregate and fine aggregate are mixed by heating. The heating mixture is rapidly cooled in a granulated state.

For example, as shown in FIG. 8, the above-mentioned mixture 3 heated at 140 ° C. to 200 ° C. is dropped onto a wire mesh 2 having a mesh 1 adjusted to a desired granular size in an appropriate amount. Mixture 3
Is dropped downward through the mesh 1, so that the size of the mesh 1 is selected to be a desired size, and then the mesh 1 is dropped to the lower water tank 4 with a desired granularity.

The water tank 4 is filled with water 9 and the fine particles 5 of a mineral substance such as tanker are placed in a floating state. The heated mixture 6 that has dropped in the desired large granular form is quenched as soon as it falls into the water 9, and the binder 8 attached to the surface of the aggregate 7 is solidified by the quenching action, so that the binder 8 does not flow down. In addition, since the fine particles 5 of the mineral substance are sprinkled on the outer surface, the desired size of the granular material a shown in FIG. 9 which no longer adheres to each other is obtained.

Since the granular material a can be stored at room temperature, it can be sold in a bag. At the time of construction, hot air is blown, heated in a container, or a hot plate is applied to fill the desired location with the binder 8 slightly dissolved on the surface. Is completed (Figure
7) . In the case of thick construction, it may be repeated several times by the lamination method.

The pavement of this embodiment exhibits the following features.
Since it is a granular mixture, heat is easily absorbed, and a heated mixture can be obtained in a short time. Since storage at room temperature can be maintained, a large amount of stock is possible, which is effective during periods of unstable demand. Even if the granular mixture is transported and brought into the site, the unused one is a stable granular mixture, so that there is no waste such as discarding the surplus on site as in the conventional product. Since the same material as the heated mixture is obtained by cooling and granulating, it is very effectively used as a road surface repair material (repair, overlay, etc.). The production is simple, suitable for mass production, and the elastic pavement material can be provided at low cost. The binder is adhered to the granular stretchable pavement material in a substantially uniform thickness, and the binder is dissolved again only by heating, and is adhered and solidified by pressing to form a pavement layer having excellent stretchability.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a conventional injection and casting method.

FIG. 2 is an explanatory view of a conventional premix injection molding method.

FIG. 3 is an explanatory view of a conventional mixture filling and molding method.

FIG. 4 is an explanatory sectional view of a pavement section constructed by the method of FIG. 1;

FIG. 5 is an explanatory sectional view of a pavement section constructed by the method shown in FIGS. 2 and 3;

FIG. 6 is an explanatory sectional view of an ideal stretchable pavement.

FIG. 7 is an explanatory sectional view of a stretchable pavement section constructed using the stretchable pavement material of the present embodiment .

FIG. 8 is an explanatory view showing a manufacturing process of the present embodiment .

FIG. 9 is a sectional view of a granular material.

[Description of Signs ] 1 Mesh 6 Heated mixture 7 Aggregate

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E01C 7/18 C08L 95/00

Claims (1)

(57) [Claims] 1. A modified asphalt-based binder and a variety of coarse and fine aggregates are heated and mixed, and the heated mixture is passed through a mesh.
A method for producing an elastic pavement material, characterized in that the pavement material is granulated by being passed through and then rapidly cooled.