JP2012092542A - Porous ceramic structure and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a porous ceramic structure capable of preventing a heat-island phenomenon, desertification and a local flood, and a manufacturing method therefor.SOLUTION: In a porous ceramic structure 1, a plurality of porous ceramic boards 10 with water permeability and water retentivity are provided, and joint materials 20 are infilled into joints among the porous ceramic boards 10, respectively. The joint materials 20 are superior in water permeation rate to the porous ceramic boards 10. A manufacturing method for the porous ceramic structure 1 includes a disposition step of disposing the porous ceramic boards 10 in an arbitrary position, and an infilling step of infilling the joint materials 20 superior in the water permeation rate to the porous ceramic boards 10 into the joints among the joint between the disposed porous ceramic boards 10.

Description

  The present invention relates to a porous ceramic structure and a method for producing the same.

 In many buildings and civil engineering structures, joint materials such as sand and mortar are filled in gaps and joints (joints) between members. The joint filled only with sand has good water permeability, but the sand is washed away by rainwater or the like. For this reason, in an environment where prevention of joint material loss is required, a mortar containing sand and cement or resin is used.

 In recent years, local floods, desertification of large cities due to a decrease in groundwater, and temperature rise due to the heat island phenomenon have become problems. These phenomena are thought to be caused by the fact that roads and buildings are paved with asphalt or concrete, so that rainwater does not permeate into the ground and moisture in the ground does not easily evaporate.

Measures against such problems are groundwater countermeasures using water-permeable mortar for civil engineering structures such as buildings and paved roads, building materials such as roofing materials and outer wall materials, and cement that has water retention for civil engineering structures such as paved roads. Heat island countermeasures using the cooling effect by transpiration of water held in building materials and civil engineering structures are being used.
For example, a water-permeable pavement binder resin using an epoxy resin (for example, Patent Document 1), water-permeable / water-retaining concrete containing fine aggregate, cement, and carboxymethylcellulose, or mortar (for example, Patent Document 2) has been proposed. Yes.

Japanese Patent Laid-Open No. 06-256468 JP 2010-24118 A

However, although the techniques of Patent Documents 1 and 2 are effective in preventing the reduction of groundwater and countermeasures against heat islands, they are not satisfactory in dealing with concentrated torrential rains in which a large amount of rain falls in a short time, such as so-called guerrilla heavy rains, and extreme heat. .
For example, a road to which the technology of Patent Document 1 is applied does not have sufficient water permeability to absorb rainwater that has fallen in a short time. For this reason, most of the rainwater flows on the road and flows into the sewer. If a large amount of rainwater flows into the sewer in a short time, local flooding may occur.
Moreover, in the road to which the technique of Patent Document 2 is applied, a water-improved road can rapidly infiltrate a large amount of rainwater but cannot retain a large amount of rainwater. For this reason, measures against heat island cannot be maintained in an environment where the heat wave continues. On the other hand, those with improved water retention can retain a large amount of rainwater but cannot penetrate the rainwater that has fallen in a short time into the ground. For this reason, most of the rainwater flows on the road and flows into the sewer. That is, the technique of Patent Document 2 cannot sufficiently prevent all of the heat island phenomenon, desertification, and local flooding.

  Therefore, the present invention is directed to a porous ceramic structure that can prevent the heat island phenomenon, desertification, and local flooding.

The porous ceramic structure of the present invention is a porous ceramic structure comprising a plurality of porous ceramic bases having water permeability and water retention, wherein joints are filled in joints between the porous ceramic bases, The joint material is characterized in that the water transmission rate is faster than that of the porous ceramic substrate.
The joint material has a water transmission rate of 7 mm / sec. Preferably, the joint material includes an epoxy resin and an aggregate, and the aggregate is preferably a porous ceramic sintered body having a particle diameter of 8 mm or less.

The method for producing a porous ceramic structure of the present invention is a method for producing a porous ceramic structure comprising a plurality of porous ceramic substrates having water permeability and water retention, and a joint material filled between joints of the porous ceramic substrates. A method for arranging the porous ceramic substrate at an arbitrary position, and filling the joint between the arranged porous ceramic substrates with a joint material having a faster water transmission rate than the porous ceramic substrate. And a process.
The joint material includes an epoxy resin and an aggregate, and the filling step includes a blending operation of blending joint materials including the epoxy resin, the aggregate, and water to obtain a blend, and a supernatant liquid from the blend. It is preferable to have a removing operation to remove, a filling operation to fill the joint with the composition from which the supernatant liquid has been removed, and a curing operation to cure the composition filled into the joint. More preferably, the mass ratio represented by the water / the joint raw material is greater than 1/11.

According to the porous ceramic structure of the present invention, the porous ceramic structure of the present invention includes a plurality of porous ceramic substrates having water permeability and water retention, and a joint material is filled in the joints between the porous ceramic substrates. In this porous ceramic structure, since the joint material has a water transmission rate faster than that of the porous ceramic substrate, heat island phenomenon, desertification and local flooding can be prevented.
According to the porous ceramic structure of the present invention, the joint material has a water transmission rate of 7 mm / sec. As described above, more rainwater can penetrate into the ground during rainfall.
According to the porous ceramic structure of the present invention, the joint material includes an epoxy resin and an aggregate, so that rain water can penetrate into the ground more quickly during rain.
According to the porous ceramic structure of the present invention, since the aggregate is a porous ceramic sintered body having a particle diameter of 8 mm or less, rainwater can permeate into the ground more quickly during rainfall.

According to the method for producing a porous ceramic structure of the present invention, a porous ceramic structure comprising a plurality of porous ceramic substrates having water permeability and water retention, and a joint material filled between joints of the porous ceramic substrates. And a step of arranging the porous ceramic substrate at an arbitrary position, and filling the joints between the arranged porous ceramic substrates with a joint material having a faster water transmission rate than the porous ceramic substrate. Therefore, a porous ceramic structure that can prevent the heat island phenomenon, desertification, and local flooding can be easily obtained.
According to the method for producing a porous ceramic structure of the present invention, the joint material includes an epoxy resin and an aggregate, and the filling step includes a joint material including the epoxy resin, the aggregate, and water. A blending operation for obtaining a blend, a removing operation for removing the supernatant from the blend, a filling operation for filling the blend with the blended liquid removed from the blend, and curing the blend filled in the joint. Therefore, a porous ceramic structure including a joint material having a higher water permeation rate can be obtained in a short time.
According to the method for producing a porous ceramic structure of the present invention, the joint material includes a joint material having a higher water transmission rate because the mass ratio represented by the water / the joint material is more than 1/11. A porous ceramic structure can be obtained more easily.

It is sectional drawing of the porous ceramic structure which concerns on one Embodiment of this invention. It is a top view of the porous ceramics structure concerning one embodiment of the present invention. It is sectional drawing of the porous ceramic structure which concerns on one Embodiment of this invention. It is sectional drawing of the porous ceramic structure which concerns on one Embodiment of this invention. It is a graph which shows the result of an Example.

(Porous ceramic structure)
A porous ceramic structure according to an embodiment of the present invention will be described below with reference to the drawings.
A porous ceramic structure 1 shown in FIGS. 1 and 2 includes a plurality of porous ceramic substrates (hereinafter simply referred to as porous ceramic substrates) 10 having water permeability and water retention, and joints are formed between the porous ceramic substrates 10. The material 20 is filled. In the present embodiment, the porous ceramic structure 1 is laid on the ground surface and used for a paved road. In FIGS. 1 and 2, reference numeral 2 denotes a surface (exposed surface) in the vertical direction. Reference numeral 3 denotes a vertically lower surface (embedded surface).

 The porous ceramic structure 1 is a structure in which a plurality of porous ceramic substrates 10 are juxtaposed in the horizontal direction without overlapping in the vertical direction, and grid joints are formed in plan view. The porous ceramic structure 1 is laid so that the exposed surface 2 is exposed to the ground and the embedded surface 3 is in contact with the ground surface (ground).

<Porous ceramic substrate>
The porous ceramic substrate 10 of the present embodiment is a plate having a rectangular shape in plan view. The size of the porous ceramic substrate 10 can be determined according to the application, and is, for example, 5 to 100 cm long × 5 to 100 cm wide × 1 to 10 cm thick.

The porous ceramic substrate 10 is not particularly limited as long as it has water permeability and water retention. For example, a material obtained by firing a mixture of diatomaceous earth and clay excluding diatomaceous earth (hereinafter sometimes referred to as clays), What baked the mixture of diatomaceous earth, clay, and slag or organic sludge, and what baked the mixture of diatomaceous earth, clay, slag, and organic sludge are mentioned. Such a porous ceramic substrate 10 has water permeability and water retention because pores in the micrometer order and / or pores in the millimeter order communicate with each other to form a communication hole.
Micrometer-order pores mean pore diameters of 1-1000 μm, and the pore diameter is a value measured using an electron microscope after a porous ceramic sintered body is cut along its thickness direction. The pores in the millimeter order mean pores having a pore diameter of more than 1 mm and not more than 300 mm, and the pore diameter is a value measured by cutting a porous ceramic sintered body along its thickness direction and using a scale. The pore diameter can be adjusted by combining the types of raw materials and the firing conditions.

In this article, “having water permeability” means that water added from one surface of the porous ceramic substrate 10 in a saturated water-containing state can be discharged from the other surface. The saturated water-containing state means a state in which the porous ceramic substrate 10 is immersed in water for 60 minutes and then pulled up from the water.
The degree of water permeability of the porous ceramic substrate 10 is represented by a water transmission rate. The water transmission rate of the porous ceramic substrate 10 is 0 mm / sec. If it is super, it is sufficient, but if it is too fast, there is a possibility that water retention is insufficient. For this reason, the water transmission rate of the porous ceramic substrate 10 is, for example, 0.1 mm / sec. Preferably, 1 mm / sec. The above is more preferable. If it is above the above lower limit, a large amount of rainwater can quickly penetrate into the ground during rainfall. The upper limit of the water transmission rate is not particularly limited, but is 100 mm / sec. The following is preferred. If it exceeds the above upper limit, the water retention or strength of the porous ceramic substrate may be insufficient.

 In this article, “having water retention” refers to those having a saturated water content of 15% by mass or more. The degree of water retention is represented by saturated water content. If the saturated moisture content of the porous ceramic substrate 10 is too low, the cooling effect may be reduced, and if it is too high, the water permeability may be insufficient. For this reason, the saturated water content of the porous ceramic substrate 10 is preferably 20% by mass or more, preferably 30 to 80% by mass, and more preferably 40 to 70% by mass.

 Examples of such a porous ceramic substrate 10 include a ceramic sintered body described in JP-A-2005-239467, a porous ceramic sintered body described in International Publication No. 10/106724 pamphlet, and the like. Examples of commercially available products include Green Biz (registered trademark, manufactured by Komatsu Seiren Co., Ltd.).

<Joint material>
The joint material 20 may be any material that has a faster water permeability than the porous ceramic substrate 10. For example, cement, epoxy resin, urethane resin, acrylic resin, polyester resin, vinyl ester resin, asphalt, rubber, etc. , A combination of a foaming agent or carboxymethylcellulose, and the like. Among them, those containing an epoxy resin and an aggregate are preferable. The joint material 20 can further improve durability and water permeability by including an epoxy resin and an aggregate.

The epoxy resin is a synthetic resin having two or more epoxy groups per molecule and capable of three-dimensional curing in the presence of a curing agent.
As the epoxy resin, known epoxy resins can be used, and examples thereof include bisphenol A type, novolac type, peracetic acid type, and reaction products of these epoxy resins and other compounds. As an epoxy resin, the binder for water-permeable pavement described in patent document 1, etc. are mentioned, for example. A commercially available epoxy resin can be used, and examples thereof include Adeka Resin Series (manufactured by ADEKA Corporation), BOTAZIT GARDEN KV (trade name, manufactured by BOTAMENT SYSTEMBAUSTOFFE GMBH & Co. KG), and the like.
Although a water-dispersed epoxy resin that has been dispersed in water and an epoxy resin that has been emulsified can also be used, those that are not water-dispersed or emulsified are preferred from the viewpoint of water permeability of the joint material 20. .

The curing agent can be determined in consideration of the temperature at the construction site, etc., and preferably cures the epoxy resin at room temperature (5 to 40 ° C.) without heating. By selecting such a curing agent, unless it is a special environment, the epoxy resin promotes curing by its own heat generation after starting the curing.
As the curing agent, for example, known curing agents such as amine curing agents such as aliphatic amines and adducts thereof, acid anhydride curing agents, imidazole curing agents, and the like can be used.

As aggregates, fine aggregates (aggregates containing 85% by mass or more passing through a sieve having an opening of 10 mm and passing through a sieve having an opening of 5 mm), coarse aggregates (85 in a sieve having an opening of 5 mm) Anything that stays by mass% or more can be used. From the viewpoint of workability when filling a small gap, fine aggregate is preferable.
From the viewpoint of water permeability, an aggregate having a particle diameter of about 1 mm to 10 mm may be used.
The particle size may be sized using a sieve.

As aggregates, for example, river sand, river gravel, mountain sand, mountain gravel, sea sand, sea gravel, natural aggregates such as pumice and volcanic eruptions, artificial aggregates such as blast furnace slag aggregates, artificial lightweight aggregates or the like Examples include recycled aggregates. These aggregates may be those obtained by pulverizing raw materials such as rocks, or commercially available products having a uniform particle diameter obtained by sieving natural products.
In addition, since the water permeability of the thing containing clay falls, it is good to use what was washed and washed away the clay. Examples of such aggregates include paddy (registered trademark, manufactured by AIF Japan Planning Co., Ltd.), which is hard natural sand obtained by removing clay from the paddy field and separating and refining sand grains.

From the viewpoint of further increasing the water permeation speed of the joint material 20, it is preferable to use a granular porous ceramic sintered body as the aggregate. The granular porous ceramic sintered body may be obtained by pulverizing a plate-like porous ceramic sintered body, or a raw material mixture is formed into a granular shape, a columnar shape, etc., and then sintered. It may be pulverized accordingly.
The particle diameter of the granular porous ceramic sintered body is preferably 15 mm or less, more preferably 8 mm or less, further preferably 0.1 to 8 mm, and particularly preferably 1 to 6 mm. If it exceeds the upper limit, the strength of the base material 20 may be reduced, and if it is less than the lower limit, the water transmission rate may not be improved.

For aggregate, use a combination of granular porous ceramic sintered body and river sand or rice sand (registered trademark) (hereinafter sometimes referred to as small sand) having a particle size of 0.5 to 1.5 mm. Is preferred. By using a granular porous ceramic sintered body in combination with small sand, the strength of the joint material can be improved.
The blending ratio of [granular porous ceramic sintered body] / [small sand] is preferably 10/1 to 1/10 (mass ratio).
From the viewpoint of design, it is preferable to use aggregates of crushed materials such as granite and marble, gravel for garden decoration, gravel for ornamental fish, and the like.

 In addition to the epoxy resin, the aggregate, and the curing agent, the joint material 20 may include pigments, various additives for the purpose of improving strength, improving flexibility, and the like.

 The water transmission rate of the joint material 20 is not particularly limited as long as it is higher than the water transmission rate of the porous ceramic substrate 10, for example, 7 mm / sec. Or more, preferably 20 mm / sec. More preferably, 30 mm / sec. The above is more preferable. If it is more than the said lower limit, a lot of rainwater can be rapidly supplied to the underground or the porous ceramic substrate 10.

(Production method)
Next, an embodiment of a method for producing a porous ceramic structure will be described with reference to FIGS. The manufacturing method of the porous ceramic structure 1 includes a disposing step of disposing a plurality of porous ceramic substrates 10 at arbitrary positions, and a water transmission rate at a joint between the disposed porous ceramic substrates 10 than the porous ceramic substrate 10. And a filling step of filling the joint material 20 with a high speed.

<Arrangement process>
The disposing step of the present embodiment is a step of disposing at an arbitrary position so that one surface of the porous ceramic substrate 10 is exposed according to the area of the road on which the porous ceramic structure 1 is laid.

 The interval between the porous ceramic substrates 10, that is, the joint width can be determined in consideration of design properties, strength required for the porous ceramic structure 1, and is preferably 5 mm to 10 cm, and more preferably 5 mm to 8 cm. preferable. If it is less than the lower limit, the water permeability of the porous ceramic structure 1 may be insufficient. If it exceeds the above upper limit, the strength of the porous ceramic structure 1 becomes insufficient, or the area of the porous ceramic substrate 10 in the porous ceramic structure 1 becomes too small, resulting in insufficient water retention. There is a risk.

<Filling process>
The filling step is a step of providing the joint material 20 at the joint between the porous ceramic substrates 10 arranged at arbitrary positions, and can be determined according to the type of the joint material 20. Hereinafter, an embodiment of the filling process will be described by taking, as an example, a case where a blend containing an epoxy resin and an aggregate is used as the joint material 20.
The filling process of the present embodiment is a process having a blending operation, a removing operation, a filling operation, and a curing operation.

≪Blending operation≫
The blending operation is an operation of blending joint raw materials including an epoxy resin, a curing agent, an aggregate, water, and, if necessary, an additive to obtain a blend.
The blending method of the joint raw material may be anything that can stir the epoxy resin, the curing agent, the aggregate, and water.

 The mixing ratio of the epoxy resin, the curing agent, the aggregate, and the water can be determined in consideration of the kind of the epoxy resin and the like. For example, the mass ratio expressed by water / joint material is more than 1/11. Preferably, more than 2/12 is more preferable (hereinafter, the mass ratio represented by water / joint raw material is referred to as “hydration ratio”). There exists a possibility that the water permeability of the joint material 20 may become inadequate that it is less than the said lower limit. In addition, the upper limit value of the amount of water in this operation can be determined in consideration of the type of epoxy resin and the like. For example, the water content is preferably 2/1 or less. If it exceeds the above upper limit value, the strength of the joint material 20 is reduced, and separation of the supernatant liquid in the removing operation described later becomes complicated.

≪Removal operation≫
The removing operation of the present embodiment is an operation for removing the supernatant liquid from the blend obtained by the blending operation. This supernatant liquid may contain a part of the epoxy resin and fine aggregate. The method of removing the supernatant liquid is not particularly limited, and examples thereof include a method (decantation) of leaving the blend still and pouring away the separated supernatant liquid.
By removing the supernatant from the blend, the curing time of the epoxy resin can be shortened.
When water was added to the epoxy resin / aggregate mixture or the supernatant was separated, there was a concern that the strength of the joint material would decrease.
However, the joint material obtained by curing the composition from which the supernatant liquid has been removed has sufficient strength. This is presumably because the epoxy resin was selectively adsorbed on the aggregate and the excess water was separated when the epoxy resin, the aggregate and water were blended.
If a water-dispersed epoxy resin, water-dispersed epoxy resin, emulsified epoxy resin or water added to this is used, water and epoxy resin are almost uniformly mixed, and it is difficult to separate the supernatant liquid. Become. As a result, it takes a long time to cure the epoxy resin at room temperature, and workability is reduced. For this reason, as an epoxy resin, what is not emulsified is preferable.

≪Filling operation≫
The filling operation of the present embodiment is an operation for filling the joint between the porous ceramic substrates 10 with the mixture from which the supernatant liquid has been removed by the removing operation. The filling of the blend can be performed by a conventionally known method.

≪Curing operation≫
The curing operation of the present embodiment is a step of curing the compound filled in the joint to form the joint material 20. The curing method of the compound can be determined according to the type of the epoxy resin or the curing agent. For example, when the curing agent can cure the epoxy resin at room temperature, the ambient temperature at which the porous ceramic structure 1 is laid is used. The method of leaving still for 8 hours-7 days is mentioned.

As described above, in the porous ceramic structure of the present embodiment, the water permeability of the joint material is faster than the water permeability of the porous ceramic substrate. For example, rainwater preferentially permeates the joint material during rain. Penetrates into the ground. In addition, since the porous ceramic substrate has water permeability, rainwater permeates the ground through the porous ceramic substrate during rainfall. For this reason, it is possible to quickly infiltrate rainwater into the ground, suppress desertification and local flooding, and prevent the occurrence of water pools on paved roads.
In the porous ceramic structure of this embodiment, since the porous ceramic substrate has water retention, the laying place can be cooled by evaporating the water held on the porous ceramic substrate. In addition, the porous ceramic substrate can exhibit a cooling effect over a long period of time by absorbing the water retained in the ground and evaporating the absorbed water from the exposed surface when the water retention amount decreases. For this reason, the heat island phenomenon can be effectively suppressed.

(Other embodiments)
The present invention is not limited to the embodiment described above.
In the above-described embodiment, the porous ceramic structure is a paved road, but the present invention is not limited to this, and the porous ceramic structure may be a building material such as an outer wall material of a building, a roofing material, It may be a paved surface of a parking lot, or a building such as a fence, stairs, or approach.

 In the above-described embodiment, the joint is formed in a lattice shape, but the present invention is not limited to this, and the shape of the joint can be determined according to the design property, the shape of the porous ceramic substrate, and the like.

In the above-described embodiment, the porous ceramic substrate is arranged side by side in the length or width direction, that is, the porous ceramic substrate has a one-layer structure in which the porous ceramic substrate is not stacked in the thickness direction. However, the present invention is not limited to this, and a multi-layer structure in which porous ceramic substrates are laminated in the thickness direction may be employed.
As the porous ceramic structure having a multi-layer structure, for example, a porous ceramic substrate 10 is laminated from the embedded surface 3 to the exposed surface 2 like the porous ceramic structure 100 shown in FIG. The joint of the base 10 may be filled with the joint material 20.
Thus, by setting it as the structure where the porous ceramic base | substrate was laminated | stacked, while it rains, rainwater is absorbed by the porous ceramic base | substrate and permeate | transmits a joint material at a still faster speed. In addition, since the contact area between the joint material and the porous ceramic substrate becomes large, rainwater that permeates the joint material quickly moves to the porous ceramic substrate. For this reason, even when there is little rainfall, the water retention amount of a porous ceramic base can be increased.

Alternatively, as in the porous ceramic structure 200 shown in FIG. 4, the porous ceramic substrate 10 is laminated in the horizontal direction from the embedded surface 3 toward the exposed surface 2, and a joint material is formed on the joint of the porous ceramic substrate 10. 20 may be filled.
In this way, by laminating the porous ceramic substrate in the horizontal direction, rainwater absorbed from the joints between any porous ceramic substrate forming an exposed surface and another porous ceramic substrate adjacent thereto, The contact area with the porous ceramic substrate that comes into contact with the rainwater until it reaches the ground increases. That is, when rainwater comes into contact with the surface of the multi-layered porous ceramic substrate in the vertical direction, a larger amount of rainwater is absorbed into the porous ceramic substrate more quickly. For this reason, generation | occurrence | production of the water pool on a paved road can be suppressed more, and the improvement of a cooling effect can be aimed at.

In the above-described embodiment, after the porous ceramic substrate is disposed (arrangement step), the joint material is filled into the joint (filling step) to manufacture the porous ceramic structure.
However, the manufacturing method of the porous ceramic structure of the present invention is not limited to this, and the porous ceramic substrate may be arranged while the compound is mixed, and the compound may be filled in the joint. Alternatively, one porous ceramic substrate may be disposed, a compound may be applied to the side surface, and another porous ceramic substrate may be disposed in contact with the applied compound.
That is, the arranging step and the filling step may be performed in parallel.

 EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated in detail, this invention is not limited by the following description.

(Raw material)
The raw materials used in the examples are as follows.
<Porous ceramic substrate>
Porous ceramic substrate: Porous ceramic substrate obtained in Production Example 1 below <Aggregate>
Granular porous ceramic sintered body A (particle diameter: 8 mm or less): A pulverized porous ceramic substrate obtained in Production Example 1. A mixture of 4 parts by mass passing through a sieve with an opening of 8 mm and not passing through a sieve with an opening of 2 mm, and 2 parts by mass of passing through a sieve with an opening of 2 mm. Saturated water content: 22% by mass.
Granular porous ceramic sintered body B: The porous ceramic substrate obtained in Production Example 1 is pulverized, passes through a sieve having a mesh opening of 15 mm, and does not pass through a sieve of 8 mm. Saturated water content: 32% by mass.

≪Saturated moisture content of granular porous ceramic sintered body≫
The granular porous ceramic sintered body is immersed in water for 60 minutes, taken out from the water, brought into contact with the fabric to such an extent that the surface water droplets are removed, and immediately measured for mass (saturated water-containing mass). ) To obtain the saturated water content. For the granular porous ceramic sintered body A, the average value of the saturated moisture content of 25 arbitrary particles (= number of samples (N)) was defined as the saturated moisture content. Moreover, about the granular porous ceramic sintered compact B, the average value of the saturation water content of arbitrary 10 particles (= number of samples (N)) was made into the saturation water content.

  Saturated moisture content (mass%) = [(saturated moisture content mass−absolute dry mass) / absolute dry mass] × 100 (1)

Sand: Rice sand (registered trademark, particle size of 1mm or less, manufactured by EF Japan Planning)
Pebble: Southern sand (trade name, particle size 3-5mm, sold at Tetori Fishland)
Epoxy resin: Adekarange EP-4100 (trade name, bisphenol A type epoxy resin, manufactured by ADEKA Corporation)
Curing agent: Adeka Hardener EH-240 (trade name, modified aliphatic polyamine, manufactured by ADEKA Corporation)
Cement: Instant cement (trade name, manufactured by Sumiwa)

(Production Example 1) Production of porous ceramic substrate <Raw material>
The raw materials used for the production of the porous ceramic substrate are as follows.
≪Organic sludge≫
For the organic sludge, activated sludge discharged through a coagulation / dehydration process from a wastewater treatment facility using an activated sludge method at a dyeing factory (Komatsu Seiren Co., Ltd., Mikawa Factory) was used. The activated sludge had an organic content (based on solid content) of 83% by mass.
≪Clays≫
As the clay, Sasame clay (from Gifu Prefecture or Aichi Prefecture) was used.
≪Diatomaceous earth≫
As the diatomaceous earth, a powdery diatomaceous earth having a water content of 5% by mass was used as a raw material for refractory bricks from the Noto district.
≪Slag≫
Cast iron slag was used as the slag. The cast iron slag _is a ductile iron slag _{SiO 2, Al 2 O 3,} CaO, Fe 2 O 3, FeO, MgO, MnO, K 2 O, the Na ₂ O as main components.

<Manufacturing method>
10 parts by mass of organic sludge and 5 parts by mass of diatomaceous earth are mixed with a mix muller (manufactured by Toshin Kogyo Co., Ltd.) to obtain a primary mixture (first mixing operation), and 30 parts by mass of clay and 55 parts by mass of slag are added to the primary mixture. Were added and further mixed to obtain a plastic mixture (second mixing operation) (the mixing step). The obtained mixture was molded with a vacuum kneading machine (manufactured by Takahama Kogyo Co., Ltd.) to obtain a strip-shaped primary molded body having a width of 60 cm and a thickness of 2 cm. The primary molded body was cut at an arbitrary pitch and width to obtain a substantially square flat plate-shaped molded body having a thickness of 2 cm (molding step).
The obtained molded body was dried with a hot air dryer (180 ° C., 0.5 hour) to a moisture content of 1% by mass or less, and then fired under the following firing conditions using a continuous sintering furnace. After firing, the side edges are cut along the four side surfaces of the porous ceramic substrate, and the pores are 25 cm long × 25 cm wide × 4 cm thick (A size), 50 cm long × 50 cm wide × 4 cm thick (B size). A quality ceramic substrate was obtained (firing process).
The obtained porous ceramic substrate had a saturated water content of 50% by mass and a water transmission rate of 3 mm / sec. Met.
As the continuous sintering furnace, a roller hearth kiln (effective length of sintering furnace: total length 15 m, dividing the sintering furnace into zones 1 to 10 of 1.5 m from the sintering furnace inlet) was used.

≪Baking conditions≫
Achieving temperature: 1050 ° C
Baking time: 65 minutes Temperature gradient:
Zone 1; 0.57 ° C./sec.
Zone 2; 0.16 ° C./sec.
Zone 3; 0.33 ° C./sec.
Zone 4; 0.52 ° C./sec.
Zone 5; 0.86 ° C./sec.
Zone 6; 0.005 ° C./sec.
Zone 7; -0.34 ° C./sec.
Zone 8; -0.72 ° C / sec.
Zone 9; -0.35 ° C / sec.
Zone 10; -0.26 ° C / sec.

<Saturated water content of porous ceramic substrate>
Saturation of the porous ceramic substrate in the same manner as the “saturated moisture content of the granular porous ceramic sintered body”, except that the porous ceramic substrate was cut into a sample of 10 cm long × 10 cm wide × 4 cm thick. The water content was measured. The number of samples (N) was 10, and the average value was obtained.

<Permeability of porous ceramic substrate>
The permeation rate of the porous ceramics substrate is measured by the water level analysis device described in the soil environment analysis method (supervised by the Japan Soil Fertilizer Society, Hirotosha, 4th edition, November 10, 2008, p. 68) (Ishikawa Prefecture). It was measured using a variable water level permeability meter (manufactured by Daiki Science and Technology Co., Ltd.) owned by the National Agriculture Research Center.
The porous ceramic substrate was hollowed out into a cylindrical shape having a diameter of 43 mm and a height of 40 mm (area of cross section perpendicular to the height direction: 1451 mm ² ) to make a sample, and this sample was immersed in water for 60 minutes to obtain a saturated water-containing state. The side surface of the saturated water-containing sample was covered with a waterproof film and attached to a measuring device using a variable water level method. In addition, the opening area of the variable level scale pipe was 56.7 mm < ² > (caliber 8.5 mm).
The time (fall time t) until the water level in the variable water level scale pipe fell 10 cm from the position (h1) at 12.5 cm above the top of the sample was measured, and the water permeation rate was determined by the following equation (2).
The water permeation rate was measured for N = 10, and the average value was obtained.

 Permeability rate (mm / sec.) = 100 (mm) ÷ Descent time t (sec.) (2)

Example 1
According to the composition of the joint material in Table 1, 2 parts by mass of the granular porous ceramic sintered body A and 1 part by mass of paddy sand were mixed to obtain an aggregate. This aggregate 200 cm3, 14 g of epoxy resin, 6 g of curing agent, and 100 g of water were mixed to prepare a blend (blending operation). The water content of this blend was as shown in Table 1.
Next, the supernatant of the blend obtained by the blending operation was separated by decantation and removed (removal operation).

Four porous ceramic substrates (A size) were arranged on the ground in 2 × 2 rows in the horizontal direction, and the mixture from which the supernatant was removed was filled in the joints of the porous ceramic substrate (filling operation). The joint width was 1 cm. After filling the blend, it was allowed to stand at room temperature for 24 hours to cure the blend to obtain a porous ceramic structure (length 51 cm × width 51 cm × thickness 4 cm).
The joint material was measured for water permeability and evaluated for wear strength, and the results are shown in Table 1.

<Performance evaluation>
500 cm ³ of water was applied to the approximate center of the exposed surface of the obtained porous ceramic structure. The splashed water was instantaneously absorbed by the porous ceramic structure, and the exposed surface was unable to retain water.
Further, when the embedded surface of the porous ceramic structure was observed immediately after the water was poured, the water penetrated the joint material. Furthermore, when a cross section of the porous ceramic substrate was observed, water penetrated into the vicinity of the exposed surface, the embedded surface, and the contact surface with the joint material, and water penetrated into a substantially central portion in the thickness direction. It was not in a state.
From these results, even when a large amount of rain falls in a short time, the porous ceramic structure of the present example quickly infiltrates rainwater into the ground and absorbs rainwater from the exposed surface, or joint material It was found that rainwater that permeated the water can be absorbed and retained from the buried surface and the contact surface between the joint material and the porous ceramic substrate.
From the above observation results, the performance of the porous ceramic structure of the present embodiment was evaluated as “◯” (good).

<Water permeability of joint material>
The water permeation rate was measured in the same manner as the “water permeation rate of the porous ceramic substrate” except that the joint material was formed into a column having a diameter of 43 mm and a height of 40 mm to obtain a sample. The water permeation rate was measured for N = 10, and the average value was obtained.

<Abrasion strength>
A joint material was formed into a disk shape having a diameter of 11.5 cm and a thickness of 1.5 cm to prepare a sample. About this sample, the abrasion test was done according to JIS A1453, and the mass w2 of the sample was measured every time the sample rotated 100 times. The abrasion test was performed until the sample rotated 500 times.
From the mass w1 and the mass w2 of the sample before the start of the test, the mass reduction rate was obtained by the following equation (3). The conditions of the abrasion test were weight: 530 g, abrasive paper: CALIBRATION OF ABRASIVE PAPER S42 Standard Stripes (manufactured by Taber). In the abrasion test, the abrasive paper was replaced with a new one every time the sample rotated 100 times.

 Mass reduction rate (mass%) = (w1-w2) ÷ w1 (3)

The obtained mass reduction rate was classified into the following evaluation criteria, and the wear strength was evaluated.
≪Evaluation criteria≫
A: Mass reduction rate after 500 revolutions is 1% by mass or less ○: Mass reduction rate after 500 revolutions is more than 1% by mass and 5% by mass or less Δ: Mass reduction rate after 500 revolutions is more than 5% by mass ×: Crushed within 500 revolutions

(Examples 2 to 5)
According to the composition of the joint material in Table 1, a porous ceramic structure was obtained in the same manner as in Example 1 except that the raw materials were blended to prepare a blend. About the joint material of each example, measurement of a water transmission rate and evaluation of abrasion strength were performed, and the result is shown in Table 1.
In addition, the performance of the porous ceramic structure of each example was evaluated in the same manner as in Example 1. As a result, since the same state as in Example 1 was observed, the performance of each example was evaluated as “◯”.

(Comparative Example 1)
A porous ceramic structure was obtained in the same manner as in Example 1 except that the joint material was a mixture of 1000 g of instant cement and 200 g of water. The joint material was measured for water permeability and evaluated for wear strength, and the results are shown in Table 1.
In addition, performance evaluation was performed on the obtained porous ceramic structure in the same manner as in the example. As a result, the porous ceramic structure absorbed all the water, but when the water was poured, Occurrence was seen. Moreover, water did not permeate the embedded surface. This is because water was absorbed by the porous ceramic substrate without passing through the joint material.
From this result, the performance of this comparative example was evaluated as “x”.

(Comparative Example 2)
A porous ceramic structure was constituted only by a porous ceramic substrate (B size). That is, it was set as the porous ceramic structure in which the joint was not formed.
The performance of the porous ceramic structure was evaluated in the same manner as in Example 1. As a result, although the porous ceramic structure absorbed all of the water, a puddle was observed when the water was poured. It was. Moreover, water did not permeate the embedded surface.
From this result, the performance of this comparative example was evaluated as “x”.

As shown in Table 1, it was found that Examples 1 to 5 to which the present invention was applied were all excellent in water permeability and water retention. In Example 5, stones of various colors were mixed, and the design was excellent.
On the other hand, Comparative Examples 1 and 2 that do not include a joint material having a faster water transmission rate than the porous ceramic substrate were inferior in water permeability to Examples 1 to 5.
From these results, it was found that the porous ceramic structure to which the present invention was applied can prevent the heat island phenomenon, desertification and local flooding.

FIG. 5 is a graph showing the transition of the mass reduction rate in the wear test, where the vertical axis shows the mass reduction rate and the horizontal axis shows the number of rotations of the rotor.
As shown in Table 1 and FIG. 5, Examples 1, 3, and 5 in which paddy sand or southern sand was blended into the joint material aggregate were conducted using only the granular porous ceramic sintered body as an aggregate. Compared to Examples 2 and 4, the wear strength increased dramatically. In addition, the joint material of Example 2, 4 was crushed when the rotation speed of the rotor exceeded 100 rotations.
From this result, it was found that the strength of the joint portion can be improved by using sand or pebbles as the aggregate.

(Example 6)
A porous ceramic structure similar to the porous ceramic structure 100 shown in FIG. 3 was obtained. Four porous ceramic substrates were arranged side by side in the horizontal direction and three layers were stacked in the vertical direction per layer. The joint between the porous ceramic substrates adjacent in the horizontal direction was 1 cm wide, and the joint between the porous ceramic substrates adjacent in the vertical direction was 1 cm thick.
About the obtained porous ceramics sintered compact, performance evaluation was performed like Example 1. FIG. As a result, since the same state as in Example 1 was observed, the performance was evaluated as “◯”.

(Example 7)
A porous ceramic structure similar to the porous ceramic structure 200 shown in FIG. 4 was obtained. Four porous ceramic substrates were arranged side by side in the horizontal direction and three layers were stacked in the vertical direction per layer. In this porous ceramic structure, porous ceramic substrates adjacent in the vertical direction are arranged so as to be shifted in the horizontal direction. The joint between the porous ceramic substrates adjacent in the horizontal direction was 1 cm wide, and the joint between the porous ceramic substrates adjacent in the vertical direction was 1 cm thick.
About the obtained porous ceramics sintered compact, performance evaluation was performed like Example 1. FIG. As a result, since the same state as in Example 1 was observed, the performance was evaluated as “◯”.

1, 100, 200 Porous ceramic structure 10 Porous ceramic substrate 20 Joint material

Claims (7)

A porous ceramic structure comprising a plurality of porous ceramic substrates having water permeability and water retention, wherein joint materials are filled in joints between the porous ceramic substrates,
The said joint material has a water-permeation speed faster than the said porous ceramic base, The porous ceramic structure characterized by the above-mentioned.   The joint material has a water transmission rate of 7 mm / sec. It is the above, The porous ceramic structure of Claim 1 characterized by the above-mentioned.   The porous ceramic structure according to claim 1, wherein the joint material includes an epoxy resin and an aggregate.   The porous ceramic structure according to claim 3, wherein the aggregate is a porous ceramic sintered body having a particle diameter of 8 mm or less. A method for producing a porous ceramic structure comprising a plurality of porous ceramic substrates having water permeability and water retention, wherein joint materials are filled in joints between the porous ceramic substrates,
An arranging step of arranging the porous ceramic substrate at an arbitrary position;
A method for producing a porous ceramic structure, comprising: filling a joint between the disposed porous ceramic substrates with a joint material having a faster water permeability than the porous ceramic substrates. The joint material includes an epoxy resin and an aggregate,
The filling step is a blending operation of blending joint materials including the epoxy resin, the aggregate, and water to obtain a blend,
A removal operation to remove the supernatant from the formulation;
A filling operation for filling the joint with the composition from which the supernatant has been removed;
The method for producing a porous ceramic structure according to claim 5, further comprising a curing operation for curing the compound filled in the joint. The method for producing a porous ceramic structure according to claim 6, wherein the joint raw material has a mass ratio represented by the water / the joint raw material of more than 1/11.

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