JPH04222702A - High-heat conductive snow-thawing paving material and paving member using same - Google Patents

Abstract

PURPOSE:To raise both heat conductivity and snow-thawing efficiency by a method in which a material obtained by mixing a base material and a ferrite of given grain size is molded into an adequate size and hardened. CONSTITUTION:A base material is mixed with a ferrite of given grain size to prepare a high-heat conductive snow-thawing paving material. The paving material is cast into molds to form an adequate size of molded product which is then hardened to obtain a flat-plate block 1 as a paving member. As the base material, Portland cement or asphalt is used, and the ferrite has a grain size of 5mm or less preferably.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

[Field of Industrial Application] The present invention relates to a paving material used for paving roads, sidewalks, etc., and a paving member using the material, and particularly to a highly thermally conductive snow melting paving material using ferrite and a paving material using the material. It relates to paving members.

0002

2. Description of the Related Art Conventionally, in snowy countries, snow-covered and frozen portions of roadways and sidewalks have been melted using electric heating wires, underground water, or heat pipes. The paving materials used for this snow melting include cement concrete, cement mortar, and asphalt mixtures that use naturally occurring sand, gravel, crushed sand or stone, or stone powder made from crushed rocks as aggregates. In addition, plates, blocks, etc. are mainly used as paving members using these materials.

0003

[Problems to be Solved by the Invention] However, the above-mentioned conventional pavement materials and pavement members using these materials have low thermal conductivity, and the thermal energy supplied from the heat source does not reach the snowy and frozen parts of the road surface. There is a problem that snow cannot be melted efficiently due to insufficient conduction.

The present invention has been made to address the above problems, and provides a highly thermally conductive snow melting pavement that has a high thermal conductivity and can sufficiently conduct the supplied thermal energy to the road surface, and can efficiently melt snowfall and ice. The object of the present invention is to provide a material and a paving member using the material.

[Configuration of the invention]

[0006]

[Means for Solving the Problems] The high thermal conductivity snow melting pavement material of the present invention is characterized in that it is formulated to have at least a base material and ferrite adjusted to a predetermined particle size, and has a high thermal conductivity. The snow-melting pavement member is characterized in that it consists of a molded body using a compounded material having at least a base material and ferrite adjusted to a predetermined particle size.

[0007]

[Operation] By using ferrite adjusted to a predetermined particle size as an aggregate, thermal conductivity is improved, and thermal energy supplied to snowy and frozen areas of the road surface is increased.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

[0009] A highly thermally conductive snow-melting pavement material according to an embodiment of the present invention is prepared by mixing Portland cement as a base material and ferrite adjusted to a predetermined particle size (5 mm or less) according to the composition shown in Fig. 1. and the thermal conductivity is 2.29
K (where K=kcal/(m·hr·°C)).

[0010] In addition, as shown in Fig. 2, a high thermal conductive snow melting pavement member using the high thermal conductive snow melting pavement material having the above structure is prepared by pouring a predetermined amount into a formwork, etc.
A flat plate block 1 formed into a size of 30 cm x 3 cm) and hardened also has a similar thermal conductivity of 2.29K. The particle size of ferrite can be varied depending on the conditions of use (strength after hardening, thermal conductivity, etc.), and other aggregates may be mixed. Furthermore, the highly thermally conductive snow melting pavement material according to one embodiment of the present invention having the above-mentioned structure is a mixture of ferrite of a predetermined particle size or ferrite obtained by crushing a molded body of an appropriate shape to a predetermined particle size, and adding a predetermined amount of cement and water. However, before the cement hardens, it may be leveled at the construction site, or it may be compacted by applying pressure at the construction site.

Next, the effects of one embodiment of the present invention will be explained using the flat plate block 1 as an example.

FIG. 3 is a diagram showing the composition of the flat plate block according to an embodiment of the present invention and a conventional flat block, and FIG. 4 shows the thermal conductivity between the flat plate block according to an embodiment of the present invention and the conventional flat block. A schematic plan view for explaining the measuring method, and FIG. 5 is a schematic front sectional view in FIG. 4. The flat plate block 1 used had the composition shown in Figure 3 (in Figure 3, "
"S0:F50:K50" is 0% sand, 50% ferrite,
The case where the volume mixture ratio is 50% for the alumina-containing furnace material is shown, and the same indications will be made below. "Fe" is an abbreviation for ferrite, and "K" is an abbreviation for alumina-containing furnace material). A conventional planar block 2 molded to the same dimensions will be explained as a comparative example.

As shown in FIGS. 4 and 5, the thermal conductivity is
A planar heater 4 is provided on the concrete floor 3, fine sand 5 is spread on the planar heater 4, and a flat plate block according to an embodiment of the present invention (hereinafter also simply referred to as "the product of the present invention") is placed in the fine sand 5. ) 1 and a conventional flat block (hereinafter also simply referred to as "conventional product") 2 are installed, and the results of measuring the surface temperature and bottom temperature of these with a thermocouple sensor 6 are compared. The thermal conductivity of the invention product 1 is 1.72K.
The thermal conductivity of conventional product 2 is 1.23K.

By the method shown in FIGS. 4 and 5, thermal energy is supplied from the plane heater 4 through the fine sand 5, and the surface temperature and bottom temperature of the product 1 of the present invention and the conventional product 2 are adjusted. The measurement results over time are shown in FIGS. 6 and 7, and FIG. 8 shows the measurement results of the surface temperature using a thermal imaging camera.

As shown in FIGS. 6 to 8, from the start of measurement, product 1 of the present invention showed higher values for both surface and bottom temperatures than conventional product 2, indicating that it had good thermal conductivity. It can be determined that there is In both the product 1 of the present invention and the conventional product 2, the surface temperature and the bottom surface temperature become almost stable after 8 hours and 20 minutes from the start of supply of thermal energy. At this time, the invention product 1
The maximum difference between the surface temperature of the product and that of conventional product 2 is 2.5.
℃ (indicated as △Tmax = 2.5℃ in Figure 8),
It can be seen that product 1 of the present invention has better thermal conductivity and is more effective in melting snow on snowy and frozen roads.

FIGS. 9 and 10 show an example in which the highly thermally conductive snow melting pavement material according to an embodiment of the present invention and the present invention product 1 are applied to the non-sprinkling snow melting sidewalks 7 and 8 in front of JR Akita Station using heat pipes. Shown below.

[0017] Note that the sidewalk sections 7 and 8 (total area 33
A layer of high thermal conductive snow-melting pavement material according to an embodiment of the present invention was applied to an area of 225 m2 with high traffic volume (8 m2).
9 (hereinafter simply referred to as ``invention product layer'') and invention product 1 were applied, and the remaining 113 m2 was constructed using conventional products.

As shown in FIG. 10 from the above-mentioned thermal conductivity measurement results, when the present invention product layer 9 and the present invention product 1 are used, the heat exchanger is heated by steam more than when the conventional product is used. The installation spacing of the heat pipes 10 that supply heat through the heat pipes has been expanded from the originally designed spacing of 25 cm to 30 cm, and the required surface temperature of the heat pipes has also been reduced from 48°C to 36°C. . This results in
There is also the effect that the heat exchanger capacity can be reduced.

Next, other embodiments of the present invention will be described with reference to the drawings.

A highly thermally conductive snow-melting pavement material according to another embodiment of the present invention is a mixture of asphalt as a base material and ferrite adjusted to a predetermined particle size (5 mm or less) according to the formulation shown in FIG. , and has a thermal conductivity of 2.12K (where K=kcal/(m·hr·°C)).

[0021] In addition, as a highly thermally conductive snow-melting pavement member using the highly thermally conductive snow-melting pavement material having the above structure, a predetermined amount of the snow-melting pavement material is poured into a formwork, etc. to form a material having an appropriate size (30cm x 30cm x 3cm).
Even if the flat plate block 11 (the figure is omitted because it has the same shape as the flat plate block shown in FIG. 2) is rolled and solidified,
It has a similar thermal conductivity of 2.12K.

[0022] The highly thermally conductive snow-melting pavement material according to another embodiment of the present invention having the above structure is obtained by heating ferrite obtained by crushing a single ferrite having a predetermined particle size or a molded body of an appropriate shape to a predetermined particle size. A predetermined amount of molten asphalt may be added and mixed, and the mixture may be used by leveling and rolling at the construction site in a heat storage state.

FIG. 12 shows a flat block 11 using a highly thermally conductive snow-melting pavement material according to another embodiment of the present invention having the above configuration.
As shown in Fig. 2, it is applied to a non-sprinkling snow melting sidewalk section, and ordinary concrete 13 with a heat pipe 10 embedded therein is provided on cut crushed stone 12, and ordinary cement mortar flat plate blocks (not shown) and ordinary asphalt are placed on this ordinary concrete 13. As a result of constructing the flat plate block made of pavement (not shown) and the flat plate block 11, supplying heat to the heat pipe 10 via a heat exchanger using ground water, and conducting on-site observation, it was found that the flat plate block made of ordinary cement mortar and the ordinary asphalt were constructed. When there is snow on the pavement surface of the flat block made of paving material, the surface of the flat block 11 has been cleared of snow, and the flat block 11 has good thermal conductivity and is effective in melting snow and ice on the road surface. confirmed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be modified in various ways without changing the gist thereof.

The composition of the ferrite can be changed in various ways, for example, as shown in FIGS. 13 and 14 ("S1
00:F0" indicates a volume ratio of 100% sand and 0% ferrite, and "Fe" is the abbreviation for ferrite.)
When the grain size of ferrite is 5 mm or less and it is used as aggregate, the thermal conductivity of concrete mortar with the same volume ratio but different mixing ratios is approximately 1.4 to 1.9. As shown, the thermal conductivity of asphalt mortar is approximately 1.6 to 2.0, and although the thermal conductivity is slightly lower than that of the highly thermally conductive snow melting pavement material of the above-mentioned example, it is better than the conventional example. Similarly to the above, it is possible to obtain the effect that the thermal conductivity is improved and the thermal energy supplied to the snowy and frozen parts of the road surface is increased.

[0026]

Effects of the Invention As detailed above, the invention provides a highly thermally conductive snow melting pavement material that has high thermal conductivity and can sufficiently conduct the supplied thermal energy to the road surface, and can efficiently melt snowfall and freezing. A paving member using the material can be provided.

[Brief explanation of the drawing]

FIG. 1 is a chart showing the formulation of a highly thermally conductive snow-melting pavement material according to an example of the present invention.

FIG. 2 is a schematic configuration diagram showing a flat block as a highly thermally conductive snow-melting pavement member according to an embodiment of the present invention.

FIG. 3 is a chart showing the composition of a flat block according to an embodiment of the present invention and a conventional flat block.

FIG. 4 is a schematic plan view for explaining a method of measuring thermal conductivity between a flat block according to an embodiment of the present invention and a conventional flat block.

FIG. 5 is a schematic front sectional view in FIG. 3;

FIG. 6 is a chart showing the measurement results of surface temperature and bottom surface temperature over time of the product of the present invention and the conventional product.

FIG. 7 is a graph showing the measurement results of surface temperature and bottom surface temperature over time of the product of the present invention and the conventional product.

FIG. 8 is a diagram showing the measurement results of the surface temperatures of the product of the present invention and the conventional product using a thermal imaging camera.

FIG. 9 is a plan view showing a non-sprinkling snow melting sidewalk section to which the product of the present invention is applied.

FIG. 10 is a schematic cross-sectional view showing a non-sprinkling snow melting sidewalk section to which the product of the present invention is applied.

FIG. 11 is a chart showing the blending of other examples of the present invention with asphalt.

FIG. 12 is a schematic cross-sectional view showing a non-sprinkling snow melting sidewalk section to which the product of the present invention is applied.

FIG. 13 is a chart showing formulations and characteristics of modified examples of the present invention.

FIG. 14 is a graph showing thermal conductivity of a modified example of the present invention.

FIG. 15 is a chart showing formulations and characteristics of modified examples of the present invention.

FIG. 16 is a graph showing thermal conductivity of a modified example of the present invention.

[Explanation of symbols]

1 Flat plate block according to the present invention 2. Conventional flat block 3 Concrete floor 4 Planar heater 5 Fine sand 6 Thermocouple sensor

Claims (7)

[Claims] 1. A highly thermally conductive snow melting pavement material, characterized in that it is formulated to include at least a base material and ferrite adjusted to a predetermined particle size. 2. A highly thermally conductive snow-melting pavement member comprising a molded body using a compounded material having at least a base material and ferrite adjusted to a predetermined particle size. 3. The highly thermally conductive snow-melting pavement member according to claim 2, wherein the molded body is formed into a flat plate using a mold. 4. The highly thermally conductive snow melting pavement material according to claim 1, wherein the base material is cement. 5. The highly thermally conductive snow melting pavement material according to claim 1, wherein the base material is asphalt. 6. The highly thermally conductive snow melting pavement member according to claim 2 or 3, wherein the base material is cement. 7. The highly thermally conductive snow melting pavement member according to claim 2 or 3, wherein the base material is asphalt.