JPH10204814A - Construction method for road with buried heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deviation of a heater layer by laying more than one layer of flexible sheets having a length larger than the laying interval of a heater layer on the heater layer constituted with protective sheet/heater/ protective sheet arranged intermittently. SOLUTION: A heater layer 1 is intermittently layer in such a manner that its length direction almost coincides with the direction of road width. This heater layer 1 is laid in two rows for each traffic lane. A lead wire 3 of a heating body is connected to a conductive wire 5 at the side of road shoulder, and the conductive wire 5 is connected to current supply facilities provided at an external portion of the road. A flexible sheet 7 is laid in the progressing direction of the road and an asphalt layer is placed on the flexible sheet 7. By this configuration, the area of adherence between the flexible sheet and a backing surface increases more than that of rubber asphalt sheet of the heater layer, so that a stress applied to the heater decreases even though the adhesive strength per unit area is not different from the conventional one. Thus, deviation or breakage of a heater layer can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a road having a structure in which a heater is buried for melting snow and ice on the road surface and preventing an accident due to a frozen road surface, so-called road heating.

[0002]

2. Description of the Related Art A heater buried under a pavement surface of a road to melt water frozen on a road surface or snow compacted on a road surface includes a linear heater arranged in a zigzag shape, a planar heater, and the like. A body is known, and particularly, a planar heating element obtained by blending carbon black with a thermoplastic elastomer, rubber, or other resin is suitably used.
In order to protect the heating element and provide durability on a road using such a sheet heating element, the present inventor has already developed a technology of laminating the top and bottom of the sheet heating element with a waterproof sheet, particularly a rubber asphalt sheet. This is disclosed in JP-A-4-161604.

[0003]

However, road heating is required in many places where road accidents may occur frequently due to freezing of the road surface, and construction is often performed in summer. Done. In addition, construction
It has a process of intermittently arranging a heater layer on the lower ground, knotting the lead wire at the end, and performing asphalt pavement thereon, and of course a pavement machine for forming the top layer, a pavement machine A heavy vehicle such as a dump truck for supplying asphalt to a vehicle passes through a heater layer laying surface that has not been paved yet. In such a case, the aforementioned Japanese Patent Laid-Open No.
When only a heater layer having a sandwich structure using a rubber asphalt sheet as a waterproof sheet described in Japanese Patent No. 161604 is used, the rubber asphalt is soft and easily flows under warm conditions. In addition, problems such as displacement of the heater layer, breakage of the lead wires and nodules, and breakage of the heater itself occur due to driving force received from the tire.

An object of the present invention is to provide a construction method which does not cause displacement of a heater layer, breakage of a lead wire or a knot portion, and breakage of a heater itself even when a road having a heater embedded structure is constructed under the above-described conditions. To provide.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a method for constructing a heater-buried road in which a heater layer is provided below a pavement surface of a road. The heater layer is preferably intermittently arranged and laid, and one or more flexible sheets having a length equal to or longer than the arrangement pitch of the heater layers are laid thereon, and asphalt is formed as the uppermost layer. A road surface forming material layer such as a pavement layer is constructed. The most significant feature of the present invention is that a flexible sheet having a length equal to or longer than the arrangement pitch of the heater layers is formed on a heater layer composed of intermittently arranged protective sheets / heaters / protective sheets. There is in the point of laying the above, by such a configuration, since the adhesive area between the flexible sheet and the base surface is increased compared to the case of the rubber asphalt sheet of the heater layer, the adhesive force per unit area is no different from the conventional Even the total load-bearing performance against shear force etc. is improved,
It is considered that displacement and breakage of the heater layer can be prevented by an action such as a reduction in stress applied to the heater.

The flexible sheet used in the present invention is preferably a rubber asphalt sheet. This rubber asphalt sheet is a sheet obtained by mixing a natural rubber or a synthetic rubber with asphalt and integrally forming it with a nonwoven fabric, and has flexibility but small elongation deformation. Rubber asphalt sheet is excellent in waterproofness, flexibility and elasticity, and also has good adhesion to asphalt, which is a pavement surface forming material to be constructed on top, and it is cheaper and more suitable than other materials in terms of price. It is.

As the protective sheet used as a material for forming the heater layer of the present invention, a rubber asphalt sheet is preferable as in the second aspect. Generally, a sheet heating element obtained by blending carbon black with a resin material has insufficient strength to be used as a layer constituting a road, but has sufficient durability by being protected by a rubber asphalt layer. can get.

In the method for constructing a heater-buried road according to the present invention, it is preferable to further construct a primer layer on the ground surface on which the heater layer is laid. By the application of the primer layer, the adhesion between the protective sheet of the heater layer, and the flexible sheet provided on the heater layer and in contact with the base surface in the gap between the heater layers intermittently laid is improved,
The durability against displacement and breakage of the heater layer due to passage of a heavy vehicle is further improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As the heater used in the present invention, all heating elements generally used for road heating can be used. Metal heating elements are arranged in a zigzag pattern, and those protected by resin sheets or resin films, carbon black, graphite,
One or more conductive materials such as carbon fiber are dispersed in various thermosetting or thermoplastic resin materials and molded into a sheet, and the electrodes are arranged and placed in a resin protective sheet. A heating element and the like can be exemplified. In the present invention,
Particularly, the use of a sheet heating element is preferred.

The sheet heating element has a thickness of 0.2 to 2 m.
m, preferably about 0.5 to 1 mm, with a width of preferably about 100 to 200 mm, a length of preferably about 500 mm and less than about the width of the road. Such a rectangular or ribbon-shaped sheet heater is provided with a lead wire at one end, and is laid on the road surface such that the lead wire is located at the shoulder of the road. This heater layer is intermittently arranged, preferably in a direction perpendicular to the direction of road travel. The disposition pitch depends on conditions such as the gradient of the road, the climatic condition, and the width of the heater. However, when the heater is 160 mm wide and the protective layer has a 300 mm width heater layer, the pitch is about 300 to 900 mm. If the distance is 300 mm or less, the heater interval becomes too close to be wasteful, and if the distance is 900 mm or more, the proportion of the road surface that remains frozen without being heated increases, which may be undesirable.

[0011] Because the lead wire is excellent in flexibility,
It is preferable to use a twisted thin copper wire.

The heater layer is composed of at least three layers of a protective sheet / heater / protective sheet, and may be constructed on the ground surface on which each component is to be constructed in this order, and the heater is previously sandwiched between the protective sheet and the protective sheet. It may be used by laminating in a shape.

The rubber asphalt sheet, which is a suitable material for the protective sheet, is a sheet obtained by mixing natural rubber or synthetic rubber with asphalt and integrating it with a non-woven fabric. It is preferable to use one having the following. The rubber asphalt sheet used for on-site construction is preferably used by laminating a release paper, a release film, or the like on the surface on which the above-mentioned adhesive processing has been performed, and cutting a roll-shaped product into a required size.

The rubber asphalt sheet may be used by applying molten asphalt as an adhesive at the time of on-site construction without any particular adhesive processing.

As the primer to be applied to the base surface, a highly reactive resin such as urethane, epoxy or acrylic resin, a prepolymer thereof, a monomer or a mixture thereof can be used. Any water type can be used. These primers are applied by a known method such as brush coating or spray coating.

The present invention will be described below with reference to the drawings.
In this example, a rubber asphalt sheet, which is a composite of rubber asphalt and a nonwoven fabric, having a thickness of about 1.5 to 2.5 mm was used for both the protective sheet and the flexible sheet. The sheet heating element used had a heating part width of 120 mm,
Including the heating section and the polyethylene terephthalate bag that accommodates the electrode wires provided in the long side direction, the sheet heating element has a width of 160 mm, a length of 3500 mm, and a thickness of 0.1 mm.
5 mm, and the planar heating element has a width of 300 mm and a length of 3 mm.
It was formed in a sandwich shape from a rubber asphalt sheet having a thickness of 600 mm and a thickness of 2.5 mm and used as a heater layer.

FIG. 1 shows an arrangement for laying a heater on a two-lane road having a width of 8500 mm. The heater layer 1 is intermittently laid at a pitch of 600 mm so that its length direction substantially coincides with the road width direction. Since the length of the heater layer is approximately equal to the width of one lane, the heater layers are laid in two rows for each lane. The lead wire 3 of the heating element is connected to the power supply line 5 on the road shoulder side, and the power supply line is connected to power distribution equipment provided outside the road. The flexible sheet 7 was laid in the traveling direction of the road while unwinding a long one having a width of 1000 mm wound in a roll shape. An asphalt layer is provided on this. The same effect can be obtained by cutting the flexible sheet to the width of the road and laying the sheet without any gaps in the same direction as the heater layer, or with a part thereof overlapping.

Although construction work was performed in summer on a steep road surface, even if a heavy vehicle such as a large dump truck passed before construction of the asphalt, damage to the heater and damage to the nodule of the lead wire due to misalignment of the heater. No such problems occurred.

FIG. 2 shows a section aa ′ of the heater layer in FIG. A rubber asphalt sheet 12 as a protective sheet is laid on the lower ground 11, a planar heating element 13 is further laid thereon, and a rubber asphalt sheet 14 as a protective layer is further laid thereon, thereby forming a rubber as a flexible sheet. Asphalt sheet 7 is laid.

FIG. 3 shows a cross section taken along the line bb 'of FIG. The heater installation surface of the road is formed in a concave shape in this example. Rubber asphalt sheets 21 and 22 are used for the road shoulders to protect the lead wires and the nodes from deformation and water penetration. In addition, in order to connect the conducting wire to power distribution equipment provided outside, through holes having appropriate intervals are provided on the vertical wall surface forming the recess.

FIG. 4A shows an example of the structure of the sheet heating element. Reference numeral 31 denotes a heating element made of a resin filled with special carbon black, provided with an electrode wire 22 in the longitudinal direction, and the electrode wire 22 and the heating element 31 are in direct contact. The heating element and the entire electrode wire are housed in a bag using a polyethylene terephthalate film 35 with the lead wire 3 extended from the electrode wire pulled out. FIG. 4B is a cross-sectional view of the planar heating element.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of an arrangement of a heater layer and a flexible sheet laid on a road surface.

FIG. 2 is a cross-sectional view taken along aa ′ of FIG. 1, illustrating a configuration of a heater layer.

FIG. 3 is a view showing a cross-section of bb 'in FIG. 1;

FIG. 4 is a diagram showing a structure of a sheet heating element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heater layer 7 Flexible sheet 12 Protective sheet 13 Planar heating element 14 Protective sheet

Claims (4)

[Claims] 1. A method for constructing a heater buried road in which a heater layer is provided below a pavement surface of a road, comprising a protective sheet / heater /
A heater in which a heater layer composed of a protective sheet is laid, on which one or more flexible sheets having a length equal to or longer than the arrangement pitch of the heater layer are laid, and a road surface forming material layer is constructed as an uppermost layer Construction method of buried road. 2. The method according to claim 1, wherein the flexible sheet is a rubber asphalt sheet. 3. The method according to claim 1, wherein the protection sheet is a rubber asphalt sheet. 4. The method according to claim 1, further comprising applying a primer layer to the ground surface.