JPH0324643Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a crack prevention sheet for preventing reflection cracks from occurring on asphalt pavement.

When asphalt pavement is laid on concrete pavement or asphalt pavement is laid on cement-stabilized roadbed, the asphalt pavement located on the joints and cracks of the underlying concrete pavement and the cracks of cement-stabilized roadbed, etc. Cracks occur in places where cracks from below are reflected. This is called reflex crack. Reflection cracks can also occur when overlaying asphalt pavement is applied over cracks in asphalt pavement.

If cracks occur in asphalt pavement, the durability of the pavement will be significantly reduced, so there is a need for measures to prevent the occurrence of cracks.

The crack prevention sheet for asphalt pavement in the present invention (hereinafter simply referred to as crack prevention sheet) is used when asphalt pavement is paved on concrete pavement, cement stabilized roadbed, asphalt pavement with cracks or open construction joints, etc. By laying a crack prevention sheet on the joints, cracks, construction joints, etc. of the underlying concrete pavement, cement stabilized roadbed, asphalt pavement, etc. (attaching it so that it does not actually come off), asphalt To provide a crack prevention sheet capable of preventing cracks from forming on asphalt pavement for a long time even when the pavement is paved or opened to traffic after paving.

That is, in the present invention, a highly elastic net-like base material is coated or permeated with asphalt, and mats such as synthetic fibers permeated with asphalt are polymerized and integrated on both sides of the base material to form a sheet. The gist of this paper is the structure of a crack prevention sheet for asphalt pavement, which is characterized by:

The crack prevention sheet of the present invention will be explained with reference to the drawings.

FIG. 1 and FIG. 2 each show a sectional view of one embodiment of the crack prevention sheet of the present invention.

In the figure, 1 is a highly elastic net-like base material such as a metal wire, metal fiber, synthetic fiber, or carbon fiber (hereinafter referred to as a high-elastic net-like base material), and is a metal wire such as steel or stainless steel. Nets, reticulated cloth, mesh, etc. made of metal fibers, aromatic polyamides, polyamides, polyesters, polypropylene, synthetic fibers such as vinylon, carbon fibers, glass fibers, etc., have high elasticity as base materials and are difficult to stretch. It requires a large tensile stress to stretch. Reference numeral 2 is a mat made of synthetic fiber, for example, nonwoven fabric, woven fabric, paper, or the like. 3 is asphalt, which is asphalt or modified asphalt obtained by mixing asphalt with rubber, synthetic resin, etc., or fillers such as mineral powder, asbestos, glass fiber, short fibers such as synthetic fibers, etc. It was added.

Asphalt 3 permeates through the mat 2, such as synthetic fiber, and both surfaces are coated with asphalt 3. Moreover, the net-like base material 1 having high elasticity is
Covered or penetrated with Asphalt 3.
Mats 2 made of synthetic fibers or the like are polymerized on both sides of a highly elastic net-like base material 1 and are integrally bonded via asphalt 3 to form a sheet-like structure as a whole. As shown in FIG. 1, powder particles 4 such as mineral substances are usually attached to the surface to prevent sticking during storage. Further, as shown in FIG. 2, powder particles 4 of minerals or the like may be attached to one side and a release sheet 5 is attached to the other side. The release sheet 5 is peeled off before use. In addition,
When using the release sheet 5, the surface of the asphalt 3 in contact with the release sheet 5 or the asphalt 3 itself may be made pressure-sensitive adhesive.

The crack prevention sheet of this invention usually has a thickness of
It is approximately 1.5 to 6 mm wide and 30 to 1 m wide, and is supplied as a roll.

The crack prevention sheet of the present invention is used in the following manner.

When laying asphalt pavement on concrete pavement, cement stabilized roadbed, asphalt pavement, etc. (Usually, a heated asphalt mixture is spread to a specified thickness using a finisher, etc., and then sufficiently compacted using point pressure with a roller. (to be paved)
First, crack prevention sheets are pasted over the joints, cracks, and seams of the concrete pavement that serves as the base. When pasting, make sure that the joints, cracks, etc. are located approximately in the center of the crack prevention sheet. Usually, a crack prevention sheet is attached using a suitable adhesive such as asphalt emulsion or asphalt. If a crack prevention sheet has a release sheet attached to one side, peel off the release sheet and apply. In this case, it is also possible to apply an asphalt emulsion or the like to the surface of the concrete pavement, etc., heat the surface of the concrete pavement, etc. or the back side of the crack prevention sheet with a burner, and then press and bond.

After pasting the crack prevention sheet over the joints, cracks, seams, etc. of concrete pavement, etc., a heated asphalt mixture is laid on the concrete pavement, etc. by a conventional method to form an asphalt pavement body. Asphalt pavement is reinforced with crack prevention sheets at joints, cracks, joints, etc. of concrete pavement.

For this reason, stress generated at joints, cracks, joints, etc. in the underlying concrete pavement is not directly transmitted to the asphalt pavement on the surface, but is absorbed and alleviated by the crack prevention sheet before being transmitted to the asphalt pavement on the surface. The introduction of cracks into the pavement is prevented.

As mentioned above, the crack prevention sheet of the present invention is an asphalt-based sheet whose core material is a highly elastic net-like base material 1 and mats 2 made of synthetic fibers provided on both sides of the base material 1. When installing asphalt pavement, it has good conformability and workability to the surface of the underlying concrete pavement, etc.
In addition, there is no problem in spreading and rolling a heated asphalt mixture on top of it, and it bonds well with the asphalt pavement after construction.

Net-like base material 1 with high elasticity in the present invention
Because of its high strength relative to elongation, it is subject to considerable tensile stress and has little elongation. Therefore, the asphalt pavement paved on top of it is reinforced with a highly elastic net-like base material to absorb tensile stress. It is possible to prevent the occurrence of cracks without being affected. Furthermore, if extreme tensile stress is applied, the asphalt pavement reinforced with a crack prevention sheet will slide on the surface of the concrete pavement, etc., relieving the stress and preventing the asphalt pavement from cracking.

In addition, matte 2 such as synthetic fibers in this invention
Because it has high shear rigidity, if it is placed on top of concrete pavement joints and cracks, it can reduce the shearing force caused by vertical fluctuations of the base that sandwich the joints and cracks that occur when traffic loads are repeatedly applied. The asphalt pavement can be absorbed and its influence on the asphalt pavement paved above it can be alleviated, thereby preventing the occurrence of cracks in the asphalt pavement.

In this way, according to the present invention, the strength against tensile stress that the mat 2 such as synthetic fiber lacks can be supplemented by the net-like base material 1, and
Since the net-like base material 1 has a high strength against elongation, the elasticity of the mat 2 made of synthetic fiber can compensate for the drawback that it easily peels off from the adhesive base due to vertical movement of the base sandwiching joints and cracks. As a result, the reinforcing effect is very large, and the effect of preventing cracks on asphalt pavement is remarkable, so the durability of asphalt pavement can be significantly improved.

The crack prevention sheet of the present invention is suitable as a reflection crack prevention sheet for asphalt pavement, and is also suitable as a waterproof sheet for waterproofing the base of road bridge pavement.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 each show a sectional view of one embodiment of the crack prevention sheet of the present invention. In the figure, 1 is a net-like base material having high elasticity;
2 is pine such as synthetic fiber, 3 is asphalt,
4 is powder particles such as mineral substances, and 5 is a release sheet.

Claims (1)

[Scope of utility model registration request] Asphalt pavement characterized by coating or see-through coating of asphalt on a highly elastic net-like base material, and polymerizing and integrating mats such as synthetic fibers coated with asphalt on both sides of the base material to form a sheet. A sheet for preventing cracks.