JP7850061B2 - Exterior structure - Google Patents

Description

This invention relates to exterior structure materials.

In recent years, various exterior structural materials have been proposed. These exterior structural materials often utilize cement-based base materials (see, for example, Patent Document 1 below).

Japanese Patent Publication No. 2001-107536

Cement-based substrates have a problem where efflorescence occurs on the surface due to aging and deterioration, causing the surface of the exterior structure to become cloudy and deteriorating its appearance. Furthermore, if tiles or other materials are fixed to the surface of the exterior structure, efflorescence can penetrate between the substrate and the tiles, potentially leading to tile detachment.

This invention was devised in view of the above-described circumstances, and its primary objective is to provide an exterior structure that can suppress the deterioration of appearance due to efflorescence over a long period of time.

The present invention relates to an exterior structure comprising a concrete base portion, partly buried and fixed in the ground, with the upper end of the remaining portion located higher than the ground level; a concrete wall base portion, positioned on the base portion and extending vertically; and a decorative portion, including a plurality of tiles fixed to the surface of the wall base portion, wherein a joining material is provided between the upper end of the base portion and the wall base portion to join them, and the joining material has a water permeability of 500 g/ ^m² or less.

By adopting the above configuration, the exterior structure of the present invention can suppress the deterioration of appearance due to efflorescence over a long period of time.

This is a front view of the exterior structure of this embodiment. This is a side view of the exterior structure of this embodiment. This is an exploded perspective view showing a portion of the exterior structure of this embodiment in a broken section. This is a partial cross-sectional view of Figure 2.

The following describes one embodiment of the present invention based on the drawings. It should be understood that the drawings contain exaggerations and representations that differ from the actual structural dimensional ratios, in order to aid in understanding the content of the invention. Furthermore, the same or common elements are denoted by the same reference numerals throughout each embodiment, and redundant explanations are omitted. Moreover, the specific configurations shown in the embodiments and drawings are for the purpose of understanding the content of the present invention, and the present invention is not limited to the specific configurations shown in the illustrations.

[Structure of the exterior structure]
Figure 1 is a front view of the exterior structure of this embodiment. Figure 2 is a side view of the exterior structure of this embodiment. As shown in Figures 1 and 2, the exterior structure 1 of this embodiment is configured, for example, as the exterior of a building. While a residential building is given as an example, it may also be a building such as a skyscraper. Furthermore, although the exterior structure 1 of this embodiment is configured as a fence surrounding a building, it is not limited to this and may also be configured as a gate or the like.

Figure 3 is an exploded perspective view showing a section of the exterior structure of this embodiment. As shown in Figures 2 and 3, the exterior structure 1 of this embodiment has an L-shaped side and its lower part is embedded in the ground. Also, as shown in Figures 1 and 2, the height H and width W of the exterior structure 1 of this embodiment are set in the same way as the exterior structures of a typical house. The height H can be set as appropriate, for example, to 2.2 m or less. The width W can be set as appropriate according to the height H, for example, to 10 cm or more.

As shown in Figure 3, the exterior structure 1 of this embodiment includes a base portion 2, a wall base portion 3, and a decorative portion 4.

The base portion 2 of this embodiment constitutes the foundation of the exterior structure 1. The base portion 2 includes a first portion 5 and a second portion 6. The first portion 5 extends approximately horizontally through the ground. The second portion 6, on the other hand, extends upward (approximately vertically) from one end of the first portion 5, with a portion of it protruding from the ground level (GL). Such a base portion 2 constitutes an L-shaped foundation. Preferably, the bottom surface 7 of the first portion 5 in this embodiment is provided with a crushed stone layer (not shown), for example, a layer of crushed stone. Such a crushed stone layer prevents the base portion 2 from settling.

The base portion 2 is made of concrete. Therefore, the base portion 2 contains cement-based materials. This base portion 2 stably supports the wall substrate portion 3 and the decorative portion 4. In this embodiment, the base portion 2 is, for example, a reinforced concrete (RC) structure with reinforcing bars (not shown) inside. This effectively maintains the strength of the base portion 2 in this embodiment, increasing its durability. However, the base portion 2 is not limited to RC construction; for example, it may be constructed as a strip foundation made of formwork concrete blocks.

As shown in Figures 1 and 2, the base portion 2 of this embodiment is divided into a part 8 and a remaining portion 9. Part 8 is the portion buried and fixed in the ground. Part 8 of this embodiment consists of a first portion 5 and a portion of the second portion 6. On the other hand, the remaining portion 9 is the base portion 2 excluding part 8, and its upper end E is located higher than the ground level (GL). The remaining portion 9 of this embodiment is the part of the second portion 6 that protrudes approximately vertically from the ground level (GL), and its appearance can be visually observed.

As shown in Figures 1 to 3, the wall base portion 3 of this embodiment is positioned on the base portion 2 and extends vertically. The wall base portion 3, like the remaining portion 9 of the base portion 2, is installed in a position approximately perpendicular to the ground level (GL). The width of the wall base portion 3 in this embodiment is set to be approximately the same as, for example, the width of the remaining portion of the base portion 2. As a result, in a side view of the exterior structure 1, the base portion 2 and the wall base portion 3 appear as a single integrated unit.

The wall base 3 in this embodiment is made of concrete. Therefore, the wall base 3 contains cement-based materials. For example, the wall base 3 in this embodiment is an RC (reinforced concrete) structure with reinforcing bars inside. This effectively maintains the strength of the wall base 3 in this embodiment, increasing its durability. However, it is not limited to RC construction; for example, it may be formed by stacking concrete blocks (not shown) made of cement-based materials. For example, basic-type blocks from the hollow blocks specified in JIS A 5406 may be used. It is preferable to insert reinforcing bars into the cavities of such concrete blocks and the cavities formed between adjacent concrete blocks, and then fill them with mortar. This improves the strength of the wall base 3 and ensures structural safety.

The decorative section 4 in this embodiment is for adding decorative appearance to the wall base section 3. The decorative section 4 is composed of a plurality of tiles 10 fixed to the surface of the wall base section 3.

As shown in Figures 1 and 2, the multiple tiles 10 of this embodiment are fixed to the front and side surfaces of the wall substrate 3. As shown in Figure 3, the multiple tiles 10 are fixed to the wall substrate 3 by an adhesive (cured adhesive) 11. While conventional adhesives can be used for the adhesive 11, a silicone-based adhesive 11 is preferred. The silicone-based adhesive in this embodiment includes both silicone-based adhesives and modified silicone-based adhesives. Such a silicone-based adhesive 11 prevents moisture, such as rainwater, from penetrating the wall substrate 3 through cracks or thinning caused by aging or other factors.

The silicone-based adhesive in this embodiment is preferably a modified silicone-based adhesive. This effectively enhances the adhesive strength between the tile 10 and the wall substrate 3. Furthermore, the modified silicone-based adhesive in this embodiment more preferably contains acrylic resin as the skeletal resin. This further enhances the adhesive strength between the tile 10 and the wall substrate 3. To effectively achieve these effects, the acrylic resin is preferably contained in an amount of 10 parts by weight or more per 100 parts by weight of the adhesive.

The adhesion between the tile 10 and the wall substrate 3 is not limited to such adhesives; for example, as in the above-mentioned Patent Document 1, it may also be adhered using a substrate preparation material (not shown) and mortar. For example, polymer cement mortar is preferred. Such polymer cement mortar can suppress the penetration of moisture, such as rainwater, into the wall substrate 3 through cracks or thinning caused by aging.

Incidentally, in conventional exterior structures, when the base portion 2 and the wall substrate portion 3, both made of cement-based material, are directly joined, moisture such as rainwater seeping into the ground penetrates from the base portion 2 into the interior of the wall substrate portion 3. This causes the alkaline components (calcium hydroxide) present in the cement-based material to leach out within the wall substrate portion 3. The leached alkaline components, along with the moisture, move to the surface of the exterior structure 1 and precipitate upon evaporation. Subsequently, the alkaline components react with carbon dioxide in the air to form efflorescence (calcium carbonate). Thus, in conventional exterior structures, efflorescence is prone to occurring on the surface of the structure. Efflorescence causes the surface of the exterior structure to become cloudy white, resulting in a deterioration of its appearance.

Furthermore, in conventional exterior structures, when tiles or similar materials are fixed to the surface of the structure, alkaline components (free alkali) leached from within the wall substrate 3 act as a deterioration factor for the adhesive 11. This can lead to tile detachment. The following explains how these problems are resolved.

[Effects and benefits of exterior structures]
Figure 4 is a partial cross-sectional view of Figure 2. As shown in Figure 4, a joining material 13 is placed between the upper end E of the base portion 2 and the wall substrate portion 3 of this embodiment to join them together. The joining material 13 of this embodiment has a water permeability of 500 g/ ^m² or less.

In this embodiment, the "water permeability" is determined based on a procedure that modifies some of the test conditions, although a water permeability test apparatus with a substrate formed from the bonding material 13 is used, similar to the water permeability test method A in JIS A 6909. In water permeability test method A, tap water is filled into the cylinder of the water permeability test apparatus up to the 200 mm mark, and the water permeability is determined from the difference between the water head height at that time and the water head height after 60 minutes. In contrast, in this embodiment, tap water is filled into the cylinder up to the 20 mm mark, and the water permeability is determined from the difference between the water head height at that time and the water head height after 24 hours. This is because, as a result of the inventors' diligent research, they found that even with some modifications to the test conditions, results equivalent to those of water permeability test method A can be obtained. The substrate is made of the same material as the bonding material 13 and is formed to a thickness of 4 mm and dimensions of 390 x 190 mm, according to the provisions of JIS A 5430.

In this embodiment, the exterior structure 1, with its connecting material 13 whose water permeability is set within the above range, makes it difficult for moisture Wa that has penetrated the base portion 2 underground to penetrate the connecting material 13 (it becomes difficult for it to seep through). This suppresses the penetration of moisture Wa into the wall substrate portion 3, and reduces the leaching of alkaline components within the wall substrate portion 3. Therefore, deterioration of appearance due to efflorescence is suppressed over a long period, and the exterior structure 1 maintains its beautiful appearance for an extended time.

Furthermore, by suppressing the elution of alkaline components within the wall substrate 3, the deterioration of the adhesive 11 is inhibited. This can potentially prevent the tiles 10 from peeling off.

To effectively exert the effects described above, it is more preferable that the bonding material 13 has a water permeability of 250 g/ ^m² or less. If the water permeability is 250 g/ ^m² or less, the penetration of moisture Wa from the base portion 2 through the bonding material 13 to the wall substrate portion 3 is more effectively suppressed, and the occurrence of efflorescence is further suppressed. On the other hand, if the water permeability is too low, the workability may decrease. From this viewpoint, it is preferable that the bonding material 13 has a water permeability of 100 g/ ^m² or more.

The bonding material 13 in this embodiment is preferably composed of mortar or resin mortar. When the bonding material 13 is composed of mortar, the permeability coefficient of the bonding material 13 can be easily controlled by adjusting the amount of water during mixing. By controlling this permeability coefficient to, for example, 1 × ^10⁻⁵ cm/s or less, the amount of water permeation of the bonding material 13 can be set to the above range. The permeability coefficient referred to here is the value obtained when mortar is used as the test specimen in the variable water level permeability test in JIS A 1218. On the other hand, when the bonding material 13 is composed of resin mortar, the permeability coefficient of the bonding material 13 can be easily controlled by adjusting the amount of resin mixed in as a binder in the mortar. Such resin fills the capillary voids that occur in the mortar, making it difficult for water to pass through the mortar. Therefore, by increasing the amount of resin mixed in, the permeability coefficient of the bonding material 13 can be reduced (to the above range), and consequently, the amount of water permeation can be set to the above range.

Moisture Wa, such as rainwater, seeping into the ground penetrates the base portion 2 and is absorbed up to the upper part of the exterior structure 1. Therefore, the lower part of the exterior structure 1 is more likely to absorb ground moisture Wa than the upper part. For this reason, the height HB (shown in Figures 1 and 2) of the upper end E of the base portion 2 from the ground level (GL) is preferably 20 cm or more. Thus, a height HB of 20 cm or more reduces the amount of moisture Wa at the upper end E. This more effectively suppresses the penetration of moisture Wa that has entered the base portion 2 through the joint material 13 into the wall substrate portion 3, thereby reducing the amount of alkaline components leaching inside the wall substrate portion 3 and further suppressing efflorescence.

The thickness HC of the jointing material 13 is preferably 2 to 20 mm. If the thickness HC of the jointing material 13 is 2 mm or more, the penetration of moisture Wa into the base portion 2 underground into the wall substrate portion 3 is suppressed, and deterioration of the appearance due to efflorescence can be suppressed over a long period of time. Furthermore, if the thickness of the jointing material 13 is 20 mm or less, construction costs can be reduced and workability can be improved.

The remaining portion 9 of the base section 2 is located below the wall substrate section 3 and is the closest to the ground level (GL) among the exterior structure 1. Therefore, moisture Wa absorbed by part 8 of the base section 2 migrates to the remaining portion 9, and alkaline components dissolve within it, making it prone to efflorescence deposition. For this reason, it is preferable that the decorative section 4 is not placed on the remaining portion 9 of the base section 2. This suppresses deterioration of the appearance of the decorative section 4 due to efflorescence.

As shown in Figures 1 to 3, it is preferable that the exterior structure 1 further includes a coping 14 provided on the upper part of the wall base 3. Such a coping 14 can suppress corrosion of the exterior structure 1 caused by rainfall.

The coping 14 may be made of, for example, marble or ceramic. The shape of the coping 14 can be set as appropriate; for example, as shown in Figures 2 and 3, it is preferable that it is shaped like a gable roof and covers the entire upper end of the wall base 3.

It is more preferable to provide a metal coping flashing plate (not shown) between the coping 14 and the wall base 3. Such a coping flashing plate can prevent rainwater from entering the wall base 3 through the coping joints. The coping 14 and the wall base 3, and the coping flashing plate and the wall base 3, may be fixed together with a silicone-based adhesive (not shown). This suppresses rainwater intrusion from the top of the wall base 3, thereby suppressing the leaching of alkaline components within the wall base 3. Therefore, the deposition of efflorescence on the surface of the exterior structure 1 is effectively suppressed.

[Note]
The present invention includes the following embodiments.

[Invention 1]
It is an exterior structure,
A concrete base portion is partially buried and fixed in the ground, with the upper end of the remaining portion positioned higher than the ground level.
A concrete wall base portion is placed on the aforementioned base portion and extends vertically,
The decorative part includes a plurality of tiles fixed to the surface of the wall base,
A joining material is provided between the upper end of the base portion and the wall base portion to join them together.
The aforementioned bonding material has a water permeability of 500 g/ ^m² or less.
Exterior structure.
[Invention 2]
The exterior structure according to the present invention 1, wherein the bonding material is mortar or resin mortar.
[3 of the present invention]
The exterior structure according to the present invention 1 or 2, wherein the height of the upper end of the base portion from the ground is 20 cm or more.
[4th Invention]
The exterior structure according to any one of inventions 1 to 3, wherein the tile is fixed to the wall substrate with a silicone-based adhesive.
[5th Invention]
The exterior structure according to any one of inventions 1 to 4, wherein the decorative part is not arranged on the remaining part of the base part.

1. Exterior structure 2. Base part 3. Wall base part 4. Decorative part 9. Remaining part of base part 10. Tiles 13. Joining material GL. Ground E. Upper end

Claims (4)

It is an exterior structure,
A concrete base portion is partially buried and fixed in the ground, with the upper end of the remaining portion positioned higher than the ground level.
A concrete wall base portion is placed on the aforementioned base portion and extends vertically,
The decorative part includes a plurality of tiles fixed to the surface of the wall base,
A joining material is provided between the upper end of the base portion and the wall base portion to join them together.
The aforementioned bonding material has a water permeability of 500 g/ ^m² or less .
The aforementioned tiles are fixed to the wall substrate with a silicone-based adhesive.
The width of the wall base portion is set to be the same as the width of the remaining portion of the base portion .
Exterior structure. The exterior structure according to claim 1, wherein the bonding material is mortar or resin mortar. The exterior structure according to claim 1 or 2, wherein the height of the upper end of the base portion from the ground is 20 cm or more. The exterior structure according to claim 1 or 2 , wherein the decorative part is not arranged on the remaining part of the base part .