JP4572437B2 - Impermeable paving material and paving method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for improving the water barrier property of asphalt. In particular, the present invention relates to a technique for improving the water shielding performance when surface treatment is performed by asphalt pavement in a waste disposal site.
[0002]
[Prior art]
Since a large amount of water is scattered on the pavement during or after raining, various water treatment measures have been taken conventionally. If moisture on the pavement penetrates into the pavement structure as it is, the bond strength between the aggregate and the asphalt will be weakened and the structural strength will decrease, or fine aggregate and filler, crusher run in the lower roadbed, etc. However, there was a problem that the surface of the pavement was uneven by being scoured by the water flow. As one of the water treatment countermeasure technologies, there is a water-permeable pavement technology that absorbs and discharges moisture on the road surface from the surface layer portion while accepting a certain decrease in strength of the pavement structure. However, it was easy to be limited to light-load roads such as sidewalks, and it was difficult to use on motorways easily due to cost and strength problems.
[0003]
Another technique is called dense-graded asphalt pavement. In contrast to the above-mentioned permeable pavement, this technology uses materials with a small particle size as fine aggregate and filler, and increases the amount of asphalt used compared to general pavement, making the pavement structure uniform and densified. To improve water shielding. In constructing this pavement structure, it was necessary to perform compaction work more carefully than general pavement in order to increase the structural density and strength.
[0004]
In addition to the road pavement as described above, surface treatment using asphalt pavement at a waste disposal site has recently been considered as an environmental problem. It was also a good important point. In other words, it is necessary to fill a gap such as a crushed stone layer on the surface of the disposal site to prevent the leakage of contaminated water by blocking water.
[0005]
[Problems to be solved by the invention]
However, the conventional dense grained asphalt pavement has the following problems.
In other words, even when sufficient compaction work must be performed to obtain water shielding properties, when the pavement base is soft or inclined, the pressing force on the base is uniform and reliable. There is a problem that a sufficient compaction effect cannot be obtained without being transmitted. Accordingly, even if it seems as if the compaction has been performed in the process, the asphalt and the aggregate are not sufficiently bonded, and it is difficult to achieve the required water shielding performance after all.
[0006]
On the other hand, even if the compaction work is reduced, the water content is increased so that fine particles in the aggregate are increased and the amount of asphalt is increased to increase the density of the entire material constituting the pavement structure. It may be possible to take measures to improve performance. However, in the same manner as described above, so-called “sagging” in which the pavement material is displaced or flows occurs on slopes and the like, and it is difficult to perform construction while maintaining an appropriate pavement structure.
[0007]
Therefore, the present invention has been made paying attention to such a conventional problem, and provides a water-impervious pavement material that exhibits excellent water shielding performance and is excellent in workability and economy.
[0008]
[Means for Solving the Problems]
The present invention has been made in order to achieve the above object, and is a pavement material with improved water barrier properties, characterized by mixing slaked lime with bentonite into an asphalt mixture composed of asphalt and aggregate.
[0009]
Then, the asphalt pavement to fill the Rukotsu material between put the waste disposal area surface, characterized by using the water-blocking paving material.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an explanatory view showing a pavement structure 10 using the water-impervious pavement material of the present invention.
[0011]
The pavement structure 10 has a lower roadbed 11 made of a crusher orchid 11a or the like, an upper layer roadbed 12 made of a particle size-adjusted crushed stone layer 12a or a bitumen stabilizing treatment layer 12b on the roadbed G that is the ground on which the pavement structure 10 is provided, It is comprised by the surface layer 13 which consists of the water-impervious pavement material 13a of this invention.
[0012]
The crusher run in the lower roadbed 11 is selected by a CBR test with a high quality such as a CBR value of 20 or more, and is appropriately mixed together with other materials such as sand and slag. The particle size-adjusted crushed stone layer 12 a in the upper layer roadbed 12 is made of crushed stone that has been conditioned by screen processing or the like, and serves as the foundation for the upper bitumen stabilizing treatment layer 12 b and the surface layer 13. As construction, compaction construction is performed by a heavy machine such as a motor grader or a load roller.
[0013]
The uppermost layer of the pavement structure 10 is provided with a surface layer 13, which is a portion where the water-impervious pavement material amount 13a of the present invention is used. This water-impervious pavement material 13a is composed of asphalt A such as straight asphalt and blown asphalt, coarse aggregate such as crushed stone and blast furnace slag (for example, sizing with maximum particle size), fine aggregate such as sand, and filler such as lime powder. It consists of aggregate K and bentonite B. At the time of construction, the water-impervious pavement material 13a is used after being sufficiently mixed in an asphalt plant and then heated to, for example, about 180 degrees to form an asphalt mixture having fluidity and viscosity.
[0014]
When prime coating is applied on the roadbed G and the upper and lower layer roadbeds 12 and 11 are subsequently laid, a tack coat is further provided thereon to improve adhesion to the surface layer 13. The asphalt mixture is spread on the tack coat by an asphalt finisher, and the surface layer 13 is formed after rolling and rolling (this construction procedure is not shown).
[0015]
Even if a large amount of moisture due to rain exists on the surface layer 13 and penetrates, the formed pavement structure 10 swells after the absorption of moisture by the bentonite B contained in the surface layer 13, thereby blocking the moisture ingress path. Water shielding is achieved.
[0016]
As another embodiment, the water-impervious pavement material 13a of the present invention may be a mixture of slaked lime in addition to asphalt A, aggregate K, and bentonite B. Various procedures performed in construction are the same as those in the above-described embodiment. If slaked lime is mixed with bentonite in this way, the mixture has a compacting efficiency comparable to that of bentonite alone, and the residual strength after watering is significantly improved. As an effect of improving the residual strength, for example, in a conventional pavement material without mixing bentonite, the residual strength hardly changes, but when mixing bentonite alone, about 75%, when bentonite is mixed with slaked lime, A residual strength of almost 100% can be obtained.
[0017]
Accordingly, it is possible to exhibit excellent properties in terms of structural strength as well as good construction efficiency and water shielding performance backed by high compaction efficiency. As the range of the mixing ratio of this slaked lime, 2 to 10% in weight percent with respect to the pavement material can be considered, but in practice, approximately 7% is appropriate at most, and most preferably, the mixing ratio is 4.5%. Become. This embodiment is not particularly shown.
[0018]
Such a pavement structure 10 does not cause “sag” even when it is formed on a steep slope in a waste disposal site, for example. And economics can be established. Therefore, surface treatment using asphalt pavement can be performed even in a waste disposal site where reliable water shielding is required.
[0019]
【The invention's effect】
As described above in detail, the aqueous paving material shield of the present invention, shielding a paving material having improved water, characterized in that the asphalt mixture comprised of asphalt and aggregates were mixed together slaked lime and bentonite It is what. Further, the asphalt pavement to fill between aggregate crushed stone or the like in waste disposal area surface, characterized by using the water-blocking paving material.
[0020]
Therefore, according to the present invention, it is not necessary to increase the density of the entire material constituting the pavement structure by increasing the amount of fine particles in the aggregate and increasing the amount of asphalt in order to obtain water shielding. In other words, it is possible to demonstrate reliable water shielding performance by mixing inexpensive bentonite and slaked lime with conventional pavement material consisting of aggregate and asphalt with a general particle size distribution and mixing ratio , and further water shielding performance. At the same time, it has an excellent effect on improving the residual strength.
[0021]
Therefore, it is possible to construct a pavement with excellent water-imperviousness while maintaining an appropriate pavement structure without seeing the occurrence of so-called “sagging” even on soft or inclined land where it is difficult to perform sufficient compaction work. It becomes. That is, the water-impervious pavement material of the present invention exhibits excellent water shielding performance and at the same time exhibits high workability and economy.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a pavement structure 10 using a water-impervious pavement material of the present invention.
[Explanation of symbols]
A Asphalt K Aggregate B Bentonite 10 Pavement structure 13 Pavement upper part 13a Water barrier material, asphalt mixture

Claims (2)

A pavement material having improved water barrier properties, characterized in that slaked lime is mixed with bentonite into an asphalt mixture composed of asphalt and aggregate. Paving method in waste asphalt pavement to fill the Rukotsu material between put disposal area surface, which comprises using the aqueous paving material barrier according to claim 1.

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