JP3221284U - Concrete block - Google Patents

Abstract

The present invention provides a concrete block which can achieve both weight reduction and strength securing. A concrete block (1) includes a pair of face shells (2) disposed facing each other, and a web (3) connecting opposing faces of the pair of face shells (2). The thickness A at the upper end in the height direction of the face shell 2 is thinner than the thickness B at the lower end, and is 15 to 20 mm. The ratio of the pressing cross-sectional area of the lower surface in the height direction of the concrete block 1 to the pressing cross-sectional area of the upper surface is 100: 95 to 130. [Selected figure] Figure 1

Description

  The present invention relates to a concrete block.

  DESCRIPTION OF RELATED ART Conventionally, in order to build frame bodies, such as a block ridge and a wall of a building, the concrete block for constructions is used widely (for example, refer patent document 1).

Utility model registration No. 3202159 gazette

  By the way, weight reduction of the concrete block for buildings is desired from the reasons, such as construction improvement. As a specific method of weight reduction, use of light weight aggregate and thinning of thickness of face shell can be considered, but due to the weight reduction of these, predetermined strength defined by Japanese Industrial Standard (JIS A 5406) In some cases, compression strength can not be met.

  An object of the present invention is to provide a concrete block which can achieve both weight reduction and strength securing.

  A concrete block according to one aspect of an embodiment of the present invention is a concrete block including a pair of face shells disposed facing each other and a web connecting the facing surfaces of the pair of face shells, the face shell The thickness of the upper end in the height direction of the concrete block is thinner than the thickness of the lower end and is 15 to 20 mm, and the pressure cross-sectional area of the lower surface in the height direction of the concrete block and the pressure cross-sectional area of the upper surface The ratio is 100: 95-130.

  According to the present invention, it is possible to provide a concrete block capable of achieving both weight reduction and securing of strength.

It is a perspective view of the concrete block concerning a 1st embodiment. It is the side view seen from the length direction (x direction) of the concrete block shown in FIG. It is a figure which shows the ratio of the up-and-down pressurization cross section based on a test result, and the relationship of compressive strength. It is a perspective view of the concrete block concerning a 2nd embodiment. It is the side view seen from the length direction (x direction) of the concrete block shown in FIG.

  Hereinafter, embodiments will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same constituent elements in the drawings are denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  In the following description, the x direction, the y direction, and the z direction are directions perpendicular to each other. The x and y directions are horizontal and the z direction is vertical. The x direction is the length direction of the concrete block. The y direction is the thickness direction of the concrete block. The z direction is the height direction of the concrete block, and the z positive direction side is the upper side, and the z negative direction side is the lower side. The length direction, thickness direction and height direction of the concrete block are the directions defined by the Japanese Industrial Standard (JIS A 5406).

First Embodiment
The first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a perspective view of the concrete block 1 according to the first embodiment. FIG. 2 is a side view seen from the length direction (x direction) of the concrete block 1 shown in FIG.

  As shown in FIG. 1, the concrete block 1 of the first embodiment is a basic-shaped cross bar block. Among the hollow blocks, the basic-shaped transverse muscle block is a block having hollows capable of arranging the longitudinal and transverse bars, and filling vertical and horizontal cavities formed by masonry with a filler.

  As shown in FIG. 1 and FIG. 2, the concrete block 1 connects a pair of rectangular plate-like face shells 2 disposed opposite to each other in the y direction with a plurality of opposing faces 2A of the pair of face shells 2 In FIG. 1, four webs 3 are provided.

  The upper surfaces of the plurality of webs 3 are horizontal surfaces at the same height as the upper surface of the face shell 2, and the lower surface of the web 3 is formed to be recessed inwardly with respect to the lower surface of the face shell 2 (z positive direction side) It is a concave surface. A plurality of (three in FIG. 1) longitudinal holes 4, a pair of longitudinal grooves 5, and a lateral groove 6 are formed by the pair of face shells 2 and the plurality of webs 3. The vertical hole 4 is a hollow that opens at the end face of the concrete block 1 in the z direction. The longitudinal groove 5 is a groove provided on the end surface of the concrete block 1 in the x direction and extending in the vertical direction (z direction), and by arranging the longitudinal bars between the concrete block 1 and another concrete block adjacent in the x direction Form a possible cavity.

  The lateral groove 6 is a groove which is provided on the bottom surface (z negative direction side end surface) of the concrete block 1 and extends in the horizontal direction (x direction), and is formed with other concrete blocks adjacent to the z negative direction Form a cavity in which the transverse muscle can be deployed. The concrete block 1 of the present embodiment has the lateral groove 6 only on the bottom side, so the pressing cross-sectional area on the bottom side is substantially equal to the area of the lower surface of the face shell 2.

  The inner side surface (facing surface 2A) of the face shell 2 is tapered such that a difference in thickness between the upper and lower sides of the face shell 2 occurs for the purpose of facilitating release from the mold at the time of manufacture. In particular, in the present embodiment, the thickness A at the upper end in the height direction of the face shell 2 is thinner than the thickness B at the lower end. The thickness A is in the range of 15 to 20 mm, and the thickness B is in the range of 17.5 to 30 mm. More specifically, the thickness A at the upper end in the height direction of the face shell 2 is preferably 14 to 20% thinner than the thickness B at the lower end. Thereby, the thickness of the face shell 2 can be reduced, and the weight of the concrete block 1 can be reduced. If the weight of the concrete block 1 can be reduced, work such as transportation and stacking of the blocks becomes easy, and the workability can be improved. Further, since the diameter of the vertical hole 4 can be increased if the thickness of the face shell 2 can be reduced, the amount of filler such as mortar which can be filled in the vertical hole 4 can be increased at the time of assembly. The durability of the housing can be improved.

In the concrete block 1 of the present embodiment, it is preferable that a lightweight aggregate (for example, mesa light etc.) having a density of 1.0 to 2.0 g / cm ³ be blended in 10 to 50% with respect to the total aggregate volume. Thereby, the weight of the concrete block 1 can be further reduced.

  Furthermore, in the present embodiment, the ratio of the pressure cross-sectional area of the lower surface in the height direction of the concrete block 1 to the pressure cross-sectional area of the upper surface (hereinafter referred to as “pressure cross-sectional area ratio”) is in the range of 100: 95 to 130. Preferably, the shape of the concrete block 1 is formed so as to be 100: 97 to 125. The pressure cross-sectional area is the area of the upper surface and the lower surface of the concrete block 1 in contact with other concrete blocks adjacent to the upper side and the lower side in the height direction at the time of building. With such a pressure cross-sectional ratio, it is possible to satisfy predetermined strength (compression strength) defined by Japanese Industrial Standard (JIS A 5406), and as a result, the concrete block 1 of the first embodiment Is both lightweight and secure in strength.

  In order to realize the pressure cross-sectional area ratio described above, the concrete block 1 of the first embodiment has a chamfered portion 7 provided on the upper surface in the height direction of the face shell 2. The chamfered portion 7 is provided to extend in the x direction at the y positive direction side end portion of the face shell 2 on the y positive direction side among the pair of face shells 2. Further, in the face shell 2 on the y negative direction side, it is provided extending in the x direction at the y negative direction side end. The net thickness of the upper surface of the concrete block 1 can be adjusted by adjusting the chamfering dimension of the chamfered portion 7, whereby the cross-sectional area ratio can be adjusted within the above-described predetermined range. For example, the larger the chamfer dimension, the smaller the net thickness and the smaller the pressure cross-sectional area on the top surface.

  The range of the above-mentioned pressure cross-sectional area ratio is a range which can satisfy the condition of the compressive strength when the following test defined by Japanese Industrial Standard (JIS A 5406) is performed. This test is described.

ここで、ｆ_２は正味断面積圧縮強さ（Ｎ／ｍｍ^２）、Ｐは最大荷重（Ｎ）、Ａ_２は試験体の正味断面積（ｍｍ^２）である。 In JIS A 5406 (Concrete block for building), the compressive strength (f2) for the net cross-sectional area (A2) of the hollow block is determined by the following equation (1) as a method for testing the strength of products. However, the net cross-sectional area (A2) is a nominal cross-sectional area calculated by a design document for block manufacture, and is taken as the larger one of the areas of the upper and lower surfaces at block stacking.

Here, f ₂ is the net cross-sectional area compressive strength (N / mm ² ), P is the maximum load (N), and A ₂ is the net cross-sectional area of the test body (mm ² ).

The compression strength required by JIS A 5406 is shown in Table 1.

From Table 1 above, the net cross-sectional area compressive strength f ₂ needs to be 16 (N / mm ² ) or more. In the compressive strength test for the net cross-sectional area, it is determined by dividing the applied load by the cross-sectional area of the larger applied surface among the upper and lower applied cross-sectional areas. The area compression strength is considered to be disadvantageous because it falls below the standard.

About concrete block 1 of a 1st embodiment, it is considered as composition which used lightweight aggregate 32.3% of aggregate volume, and changed a ratio of up-and-down pressurization cross section, and created a plurality of test bodies. The maximum load P was measured for each of a plurality of specimens were calculated net cross-sectional area compressive strength f ₂ using the above equation (1).

  The relationship between the ratio of the upper and lower pressure cross sections and the compressive strength is shown in FIG. The horizontal axis in FIG. 3 indicates the ratio of the pressing cross-sectional area of the upper surface when the pressing cross-sectional area of the lower surface of the concrete block 1 is 100. The vertical axis in FIG. 3 indicates the compression strength P. In FIG. 3, the test results of the above-mentioned plurality of test specimens are plotted in black circles, and an approximate curve based on the test results is illustrated by a dotted line.

As shown in FIG. 3, when the range of the ratio of the pressure cross-sectional area on the upper surface is 95 to 130, the net cross-sectional area compressive strength f ₂ is 16 (N / mm ² ) or more. It can be seen that the requirements are met. Furthermore, when the ratio of the pressure cross-sectional area on the upper surface is 97 to 125, the net cross-sectional compressive strength f ₂ is 18 (N / mm ² ) or more, and the requirement of JIS A 5406 is made more reliable. It turns out that it is a more appropriate range that can be satisfied.

Second Embodiment
The second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a perspective view of a concrete block 1A according to a second embodiment. FIG. 5 is a side view as seen from the length direction (x direction) of the concrete block 1A shown in FIG. The configuration of FIGS. 4 and 5 is the same as that of FIGS. 1 and 2.

  As shown to FIG. 4, FIG. 5, the concrete block 1A of 2nd Embodiment differs in the structure for implement | achieving a desired pressurization cross-sectional area ratio from 1st Embodiment. Specifically, the concrete block 1A has a recess 8 formed by recessing at least a part of the upper surface of the web 3 in the height direction. The net thickness of the upper surface of the concrete block 1A can be adjusted by adjusting the size of the area of the recess 8 and the pressure cross-sectional area ratio can be adjusted to the above-described predetermined range. For example, as the range in the thickness direction of the recess 8 is increased, the net thickness is reduced, and the pressure cross-sectional area of the upper surface can be reduced.

  In the example shown in FIGS. 4 and 5, the recess 8 is provided on a part of the central portion in the thickness direction of the upper surface of the web 3, but provided on one side of the pair of face shells 2 Alternatively, the entire upper surface of the web 3 may be recessed.

  The present embodiment has been described above with reference to the specific example. However, the present disclosure is not limited to these specific examples. Those appropriately modified in design by those skilled in the art are also included in the scope of the present disclosure as long as the features of the present disclosure are included. The elements included in the above-described specific examples, and the arrangement, conditions, and shapes thereof are not limited to those illustrated, but can be appropriately modified. The elements included in the above-described specific examples can be appropriately changed in combination as long as no technical contradiction arises.

  In the above-described embodiment, although a basic-shaped cross bar block is illustrated as the concrete block 1, any cross bar block may be used as long as it has the lateral groove 6 on the block bottom surface side. Further, a block other than the hollow block such as a mold block may be used.

1 and 1 A concrete block 2 face shell 3 web 7 chamfer 8 chamfer

Claims (6)

A concrete block comprising: a pair of face shells disposed facing each other; and a web connecting the facing surfaces of the pair of face shells,
The thickness of the upper end in the height direction of the face shell is thinner than the thickness of the lower end, and is 15 to 20 mm,
The ratio of the pressing cross-sectional area of the lower surface in the height direction of the concrete block to the pressing cross-sectional area of the upper surface is 100: 95 to 130.
Concrete block. The ratio of the pressing cross-sectional area of the lower surface in the height direction of the concrete block to the pressing cross-sectional area of the upper surface is 100: 97 to 125,
The concrete block according to claim 1. The thickness of the upper end in the height direction of the face shell is 14 to 20% thinner than the thickness of the lower end.
The concrete block according to claim 1 or 2. It has a chamfer provided in the height direction upper surface of the face shell,
The ratio of the pressing cross-sectional area of the lower surface of the concrete block in the height direction to the pressing cross-sectional area of the upper surface is adjusted within a predetermined range by the chamfering dimension of the chamfered portion.
The concrete block according to any one of claims 1 to 3. It has a recess formed by recessing at least a part of the upper surface in the height direction of the web,
The ratio of the pressing cross-sectional area of the lower surface of the concrete block in the height direction to the pressing cross-sectional area of the upper surface is adjusted within a predetermined range according to the size of the area of the recess.
The concrete block according to any one of claims 1 to 4. Lightweight aggregate with a density of 1.0 to 2.0 g / cm ³ is blended at 10 to 50% of the total aggregate volume,
The concrete block according to any one of claims 1 to 5.

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