JP2011064031A - Cooling device of roof deck - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling device of a roof deck requiring little maintenance, eliminating the running cost and a need for a watering device, roof deck waterproofing, etc. to add a water-retaining function, and imparting a cooling function comparatively easily and at low cost. <P>SOLUTION: Granular or massive Ryukyu limestone 2 which is porous and has a specific gravity of 2.1-2.4 and a grain size of 20-60 mm is laid on the roof deck of a building etc. in a manner of forming a layer. The Ryukyu limestone 2 is surrounded by a constraining body 3, having a water discharging/ventilation means, so that the layer structure can be maintained. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rooftop cooling device for cooling a building.

  In general, there are many concrete buildings in urban areas, and road surfaces such as roads are covered with concrete or asphalt. These concrete surfaces rise in temperature due to solar heat and reach 65 to 70 ° C., for example, on the roof of a building in the summer, which is one of the factors causing the urban heat island phenomenon.

  In particular, in a concrete building, the internal temperature also rises, so that the indoor environment is deteriorated and the consumption of electric power energy such as cooling is a problem.

  Various countermeasures have been proposed as countermeasures against the temperature rise problem of such buildings, such as a method of reflecting solar heat by painting with a highly reflective paint, a method of cooling buildings with the heat of vaporization of water, etc. is there. Of these methods, the paint method has the effect of reducing the amount of incident heat, but does not cool the object warmed by solar heat.

  Moreover, as a method of cooling a building with the heat of vaporization of water, there are a method of watering, a method of providing a material having water retention, a method of greening, and the like.

  Of these, the water spraying method has been tried because it is highly effective, but since the supplied water flows away, the effect of requiring a large amount of water is not sustained.

  In the method of revegetation, when planting rooftops, a concrete planting base is provided on the mortar surface of the roof, and the soil is spread by completely separating the planting base from the frame surface. For concrete, it is common to use porous concrete with continuous voids formed of Portland cement and single-grain coarse aggregate. As described above, a natural organic material such as peat moss is filled with the soil on the surface side of the gap.

Various methods for providing water-retaining materials have also been proposed. However, Patent Document 1 listed below is a lightweight concrete pavement method with excellent water permeability and water retention that provides the same cooling and heat insulation effects as when the rooftop is greened. It is a water-retaining and water-permeable concrete block, and without adding an additive that supplements strength, a blend of 11 to 50% by weight of pumice with a particle size of 3 to 20 mm and 50 to 38% by weight of Portland cement, water Spread the ready-mixed concrete made of water-kneaded and water-permeable concrete with 40-50% by weight dispersed.
JP-A-2005-97884

  In Patent Document 1, when placing water-retaining and water-permeable concrete, a synthetic resin pipe having a large number of small holes is buried, and when it is dried, water is poured into this pipe, Impregnate water retaining and water permeable concrete with water. It is said that rain water stored in a water tank may be used as water to be used.

  In this way, in conventional methods for preventing high temperatures on the roof, except for methods such as heat-shielding / reflective coatings, a root-holding base that assumes water retention, such as rooftop greening, and porous water absorption / It is common to install water retaining materials on the rooftop or roof and use the heat shielding effect of the water retaining layer to prevent high temperatures.

  These require a water retention layer to maintain a certain amount of moisture, and the inclusion of moisture reduces the heat shielding effect that limits weight, and the biggest problems are When clear weather continues, moisture evaporates and the heat shielding effect decreases, so water supply is required, installation and maintenance of the equipment is necessary, and costs are high.

  The problem with water retention is that the clear water continues, moisture remaining in the water retention layer causes heat accumulation, the entire water retention layer becomes hot, and the high temperature is conducted to the rooftop floor surface, reducing the heat shielding effect. Things happen.

  In addition, porous concrete is generally used for porous water absorption / retention, but porous concrete is made of natural aggregate such as cement and crushed stone. , Handling and construction are inconvenient.

  The Portland cement of Patent Document 1 is strongly alkaline and prevents the germination of plant seeds, or the plant fibers and seeds filled are easily washed away by rainwater.

In addition, it is necessary to take into consideration the load and drainage on the rooftop when greening the rooftop. As a matter of fact, in the case of rooftop greening in an existing building, seismic load It is said that 130 kg / m ² is the limit. In addition, the rooftops of high-rise buildings where rooftop greening is necessary are generally flat roofs without handrails around them, and it is not taken into consideration that the roof is loaded.

  Therefore, when greening such a place, the load must be a lightweight method.

  In addition, it is necessary to secure a drainage route for soil for vegetation, and an appropriate drainage port is provided in the lower part of the wall surrounding the planting, and the drainage port is covered with a net to prevent the outflow of soil. Means are provided.

  However, with such a method, drainage efficiency is poor, and even though the drain outlet is covered with a net, it is impossible to block all dust from the soil, and the drain on the roof is frequently clogged. was there.

  When water supply facilities are required, an increase in static load on the roof due to water storage may become a problem.For rainwater storage types that do not have a sprinkler, rainwater supply is interrupted and the product becomes semi-dry. Due to the water vapor in the layer, heat accumulation occurs and the cooling action is hindered.

  The object of the present invention is to eliminate the inconvenience of the conventional example, almost no maintenance is required, no running cost is required, and there are no facilities such as a watering device or a roof waterproof for adding a water retention function. An object of the present invention is to provide a rooftop cooling device that can be provided with a cooling function easily and inexpensively.

  In order to achieve the above-mentioned object, the present invention according to claim 1 is a method for producing a granular material made of limestone having a porous and specific gravity of 2.1 to 2.4 and a particle size of 20 to 60 mm on a rooftop of a building or the like. The present invention according to claim 2, in which the lump is laid in layers, and the gist of the present invention according to claim 2 is that the granule or lump is Ryukyu limestone, and claim 3 is that the Ryukyu limestone is coral limestone. is there.

According to this invention of Claim 1, by laying the granular material which consists of limestone in layered form (two or more layers),
(1) Because of the light specific gravity (about 2.3), there is little increase in load on the roof.
(2) Since the limestone is porous, the thermal conductivity of the granular material itself is low.
(3) The granular materials are in a point contact state with each other, the conductivity of incident heat due to direct sunlight decreases, and the amount of heat input to the roof / roof surface decreases.
(4) Since the air flow passage is configured in a wide range between the granular materials, the generation of the rising air stream of the air heated in the layer is promoted.
(5) Due to the rising airflow, air (low temperature: approximately 35 degrees or less) at the same temperature as the shaded outside air (because the lower part of the layer is shaded) is always in contact with the roof / rooftop, which can suppress the temperature rise. .

  According to the second and third aspects of the present invention, Ryukyu limestone, particularly coral limestone is suitable as the limestone having such a porous and specific gravity of 2.1 to 2.4 and a particle size of 20 to 60 mm. Is.

  The gist of the present invention described in claim 4 is that the granular or lump is surrounded by a restraint having drainage / ventilating means so as to maintain the layer structure.

  According to the fourth aspect of the present invention, the layered state can be maintained by enclosing with the restraint body having the drainage / ventilating means, and the dry state is maintained by always supplying air into the layer of the granular material. By sagging, there is no heat accumulation caused by water vapor in the layer. The temperature of the granular material layer itself is reduced by the ventilation means. Furthermore, drainage is possible even when rainwater is received, and water does not accumulate between layers.

  The gist of the present invention described in claim 5 is that the layer of the granular material or the mass is composed of an upper layer as a heat shielding layer, an intermediate layer as a heat conduction inhibiting layer, and a lower layer as a cooling layer.

  According to the present invention of claim 5, the role of each laying layer is that the upper heat shielding layer is subjected to direct sunlight as a surface layer and becomes a high temperature (45 to 55 ° C.) portion. This high temperature causes heat radiation from the surface and creates an upward flow. This upward flow pulls up air from the lower layer. (35 ℃ or less) (heat shield, high temperature body)

  The heat conduction blocking layer supports the surface layer and receives heat conduction from the surface layer, but the contact surface is small to reduce heat conduction to the rooftop and roof surface (35 to 40 ° C.) Have a role.

  Since the lower cooling layer does not emit sunlight through the entire laying layer, it secures a shadowy low-temperature (35 ° C. or lower) air amount and supplies the air to the surface layer. And inflow of the new air (35 degrees C or less) from the outside of a laying layer occurs. (Shadow air low temperature layer / cooling body)

  The gist of the present invention described in claim 6 is that a granular material or lump made of Ryukyu limestone is covered with a scattering prevention net.

  According to the present invention of claim 6, it is possible to easily take measures against air scattering by covering with a scattering prevention net.

  As described above, the rooftop cooling device of the present invention requires almost no maintenance, does not require running costs, and does not require watering equipment or rooftop waterproofing equipment for adding a water retention function. Therefore, the cooling function can be provided easily and inexpensively.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal side view showing an outline of a cooling apparatus for a rooftop according to the present invention. In the figure, reference numeral 1 denotes a rooftop with many concrete surfaces.

  In the present invention, limestone, particularly Ryukyu limestone 2 is laid on the rooftop floor 1 in two or more layers.

  Ryukyu limestone is porous and has a specific gravity of about 2.3. In the present invention, Ryukyu limestone is used as a granular material or a mass having a particle size of 20 to 60 mm as shown in FIG.

  Ryukyu limestone 2 is a limestone formation widely distributed in the Nansei Islands. It was formed in the Pleistocene by the function of coral reefs. Named by Nagakatsu Yabe and Masashiro Hanzawa in 1925 (Taisho 14). It is widely distributed from the central part of the Nansei Islands to the southern part, and in Okinawa Prefecture, it occupies about 30% of the land. The maximum thickness is as much as 150 meters. It contains many pores and has the property of infiltrating a large amount of groundwater.

  Furthermore, the layered structure of the granular material or block of the Ryukyu limestone 2 was maintained, and the granular material layer was surrounded by a restraint 3 having drainage / ventilating means.

  The type of Ryukyu limestone 2 varies depending on the water depth of the formed sea area, and includes coral limestone, lime algae limestone, cycloperius limestone, clastic limestone, and the like.

  Coral limestone is a limestone that contains a lot of fossil reef-building coral, limestone sphere limestone is a limestone that contains a lot of limestone balls, and cycloperius limestone is a lot of large foraminifera such as cycloperius and opaculina Limestone is a limestone that contains many debris such as foraminifera, corals, algae, and bryozoans. It is also classified into coral limestone, shell limestone, and foraminiferal limestone according to the types of biofossil contained.

  In the present invention, any type of Ryukyu limestone may be used, but coral limestone is preferred because of its availability.

  An example of the restraint body 3 is a frame body 5 in which through holes 4 for drainage and ventilation are formed, and in order to maintain the layer structure of the Ryukyu limestone 2 that is a granular material or a lump, A rectangular or other polygonal frame with vertical and horizontal dimensions.

  The frame body 5 is composed of layers of Ryukyu limestone 2 packed in layers with a space 6 therebetween. This interval 6 may be wide enough to ensure the function of draining and ventilating the frame 5. In the figure, 7 indicates a ceiling portion and 8 indicates a room.

  Further, the upper surface of the layered Ryukyu limestone 2 is covered with a scattering prevention net 9 as a measure against wind scattering. This anti-scattering net 9 can be made of a synthetic resin net for bird guards such as crows, which can be covered by covering the top opening of the frame 5 with this, or by forming the anti-scattering net 9 in a bag shape. For example, the Ryukyu limestone 2 is wrapped and packed in the frame 5. The scattering prevention net 9 may be a wire net.

  FIG. 3 shows a single frame 5 in which such a Ryukyu limestone 2 is packed in a layered structure.

  The shape of the frame 5 is not limited to a rectangle as shown in the figure, but may be a circle or a polygon. Although not shown in the figure, an octagon is formed and arranged with the interval 6 in between so that a tortoiseshell pattern is obtained. Arrangement is also possible.

  Further, FIG. 4 shows the frame 5 as a mesh bottom 14 as drainage / ventilation means for the frame 5, and the mesh of the mesh bottom 14 becomes a through hole for drainage and ventilation. In this case, the frame 5 is provided with legs 5a so as to secure the lower space 15. In FIG. 4, illustration of clogging of Ryukyu limestone 2 and illustration of the scattering prevention net 9 are omitted, but they are the same as in FIG.

  Thus, as shown in FIG. 1, the granular or massive layer of Ryukyu limestone 2 comprises an upper layer α as a heat shielding layer, an intermediate layer β as a heat conduction inhibiting layer, and a lower layer γ as a cooling layer.

  The contact surface of each solid in the form of a layer is composed of dots or intermittent lines, and 60% or more of the outer surface of each individual is a non-contact surface and has a structure that directly contacts air.

  Next, the usage and action will be described. At the contact point, the heat shielding layer, which is the upper layer α, heats the surface of the laying layer that receives direct sunlight (45 to 50 ° C.), and the conduction to the next layer is a point portion. However, since the area is small, the amount of conduction is reduced (35 to 40 ° C.), and heat is radiated into the air from the outer surface of the surface layer solid.

  Here, because of the high temperature, an upward flow is generated and the heat is dissipated from the upper layer α to the sky, and the air flow causes the middle layer β to pass through the heat conduction-inhibiting layer and the lower layer γ to pass through the middle layer β. Then, the effect of cooling the inside of the layer occurs.

  The solid contact with the rooftop floor 1 or the roof surface is also composed of dots or discontinuous lines like the solids, and 60% or more of the floor surface is in direct contact with air.

  The middle layer β supports the upper layer α as a surface layer of the heat conduction-inhibiting layer and receives heat conduction from the upper layer α. However, the small contact surface reduces heat conduction to the rooftop floor 1 or the roof surface (35 ~ 40 ° C).

  Since the middle layer β and the lower layer γ are not exposed to sunlight across the entire laying layer, the amount of air at a low temperature (below 35 ° C.) is secured, and the air is supplied to the upper layer α. And inflow of the new air (35 degrees C or less) from the outside of a laying layer occurs. (Shadow air low temperature layer / cooling body)

  The temperature and temperature of the air flowing into the rooftop floor 1 or the roof surface by the structural function of the laying layer is 40 ° C. at the maximum and 35 ° C. or less when entering the shaded portion. Due to the air temperature of 35 ° C. or lower, the rooftop floor 1 or the roof surface does not become 35 ° C. or higher, and the temperature of the ceiling below that temperature is lowered, and heat conduction into the room is reduced.

  FIG. 11 shows the results of thermography measurement, where ● is the temperature of the rooftop floor 1, ■ is the temperature of the ceiling 7, and □ is the temperature of the room 8. (See Figure 1)

  By the way, when there is no granular or lump layer of Ryukyu limestone 2, the surface temperature of the rooftop floor 1 is 60 ° C, the internal temperature is 45 ° C on average, the temperature of the ceiling 7 is 42 ° C, the temperature of the room 8 Is 40 ° C.

  On the other hand, when there is a granular or massive layer of Ryukyu limestone 2, the temperature of the upper layer α is 45 ° C. to 50 ° C., the temperature of the middle layer β is 40 ° C., and the temperature of the lower layer γ is 35 ° C. or less. The inside temperature of the rooftop floor 1 is 35 ° C. or less on average, the temperature of the ceiling 7 is 30 ° C. or less, and the temperature of the room 8 is 28 ° C. or less.

  Also, when there is wind, due to the unevenness of the surface of the laying layer, a part of the wind (air) passing through the sky enters the laying layer, and part of it reaches the bottom layer, and the entire temperature in the laying layer is Has the effect of cooling with.

  For this reason, although an upwind part exhibits the temperature close | similar to temperature, a leeward part becomes 2 to 3 degreeC hotter than an upwind part with the air which passed the laying layer and absorbed the heat. For this reason, it is good to provide the clearance gap which escapes air from a laying layer at intervals of about 2-4 m, without laying down a laying layer in the whole.

  On the other hand, since water retention is not requested | required with respect to the roof floor 1 or a roof surface, it can permeate | transmit water with respect to rainwater as it is. Rainwater is discharged from the through holes 4 for drainage and ventilation.

  FIG. 5 shows another embodiment of the present invention, which uses a mesh net as a restraint 3 that maintains the granular structure or mass of the Ryukyu limestone 2 and has drainage / ventilating means for the granular layer. Bag 10 was used. If a layer is formed in the bag 10 made of the mesh net, and laid in a futon shape, the bags 10 made of the individual mesh nets are bound and fixed together, so that the scattering prevention net is not necessary.

  In the case where the laying layer is installed on the roof, as a simpler method, a material in which a laying material is packed in a bag instead of the frame body 5 is used.

  Further, when separating into a futon shape, it is possible to prevent the granular or lump of the Ryukyu limestone 2 from being separated in the bag 10 by sewing the surface and the bottom. In order to maintain the granular or massive layer of Ryukyu limestone 2 in the bag 10, it is desirable that the size is about 30 mm to 60 mm.

  This bag-like one is effective for folding roofs and deformed rooftops. FIG. 6 shows a case where it is installed on the folding roof 11, and in order to allow air to pass through the bottom of the laying layer, a mesh pipe 12 having a large number of through holes 12a as shown in FIG. Raise the floor to 12 to improve ventilation.

  Further, when the area of the laying layer is large, as shown in FIGS. 7 and 8, a ventilation member such as the mesh pipe 12 is used and the ventilation is divided and improved. This section is also useful as a stabilization method to prevent the laying layer from being broken or more unilaterally.

  In this case, it may be further surrounded by a frame 5 as shown in FIGS. 1 and 3, but as shown in FIG. 9, a ventilation member such as the mesh pipe 12 may be directly used as the frame 5. Good.

  FIG. 12 shows a case where a layered structure of granular or lump of Ryukyu limestone 2 of the present invention is laid on the rooftop floor 1 or roof surface, and a cooling tower or an air conditioner outdoor unit 13 is further installed thereon. The comparison with the case where the Ryukyu limestone 2 is not provided is shown by the temperature value.

  In addition, although illustration is abbreviate | omitted, the rooftops, such as a building in this invention, say on a cooling tower, and the layered structure of the granular material or block of the Ryukyu limestone 2 of this invention can also be laid on a cooling tower.

It is a vertical side view which shows the outline | summary of the cooling device of the rooftop of this invention. It is explanatory drawing of the Ryukyu limestone used with the cooling device of the rooftop of this invention. It is a perspective view of an important section showing one embodiment of a rooftop cooling device of the present invention. It is a perspective view of the principal part which shows other embodiment of the cooling device of the rooftop of this invention. It is a perspective view which shows 2nd Embodiment of the cooling device of the rooftop of this invention. It is a perspective view which shows 3rd Embodiment of the cooling device of the rooftop of this invention. It is a perspective view which shows 4th Embodiment of the cooling device of the rooftop of this invention. It is a perspective view which shows 5th Embodiment of the cooling device of the rooftop of this invention. It is a perspective view which shows 6th Embodiment of the cooling device of the rooftop of this invention. It is a perspective view of a mesh pipe. It is a graph which shows the measurement result by thermography. It is explanatory drawing which shows the other example of installation of the cooling device of the rooftop of this invention.

DESCRIPTION OF SYMBOLS 1 ... Rooftop 2 ... Ryukyu limestone 3 ... Restraint body 4 ... Drainage and ventilation hole 5 ... Frame body 5a ... Leg part 6 ... Spacing 7 ... Ceiling part 8 ... Indoor 9 ... Anti-scattering net 10 ... Bag by mesh net DESCRIPTION OF SYMBOLS 11 ... Folding half roof 12 ... Mesh pipe 12a ... Through-hole 13 ... Air-conditioning outdoor unit 14 ... Net bottom 15 ... Lower space

Claims (6)

  A rooftop cooling apparatus characterized by laminating a granular material or a lump of limestone having a porous and specific gravity of 2.1 to 2.4 and a particle size of 20 to 60 mm on a rooftop of a building or the like.   2. The rooftop cooling device according to claim 1, wherein the granular or lump is Ryukyu limestone.   The rooftop cooling device according to claim 2, wherein the Ryukyu limestone is coral limestone.   The rooftop cooling apparatus according to any one of claims 1 to 3, wherein the granular material or the lump is surrounded by a restraint body having drainage / ventilating means so as to maintain a layer structure.   The rooftop cooling device according to any one of claims 1 to 4, wherein the granular or lump layer is configured such that the upper layer is a heat shielding layer, the middle layer is a heat conduction inhibiting layer, and the lower layer is a cooling layer.   The rooftop cooling device according to any one of claims 1 to 5, wherein a granular or lump of Ryukyu limestone is covered with a scattering prevention net.

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