JP2006183334A - Coating block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating block capable of not only securing sufficient stability to wave power but also easily securing structural strength, while being superior in economic efficiency. <P>SOLUTION: This coating block has a concrete block body and a plurality of opening parts penetrating in its thickness direction through this block body. The block body has a frame body part for constituting its outer peripheral edge part, and a grating beam part for forming at least four or more of opening parts by partitioning a space surrounded by this frame body part by beams while mutually crossing. Its whole contour shape is formed in a grating shape. The opening area ratio (Ao/Ac) of the sum (the total opening area : Ao) of the planar area of the plurality of opening parts to a coating area (Ac) of the block body, is set in a range of 0.3≤Ao/Ac≤0.6. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a covering block used to cover the surface of a mound portion of a composite levee, an artificial reef, an inclined revetment, etc., and preferably on the foundation material layer on which a foundation material such as rubble is laid The present invention relates to a covering block that is spread in many directions and ensures the stability of a base material layer.

  Conventionally, this type of covering block has, for example, a flat rectangular block main body having a predetermined thickness and a protrusion projecting upward on the upper surface of the block main body. A concrete revetment block with a front meshing part and a rear meshing part formed on the rear surface part, and a semi-curved curved surface with an inward semicircular shape on the front and rear surfaces of the projection part (patented) No. 2,519,173), and the planar shape is rectangular, and has a concave portion for engagement at the center of the front and rear end surfaces, a stepped portion is provided in the middle portion in the front-rear direction of the upper surface, and a through hole penetrating vertically is further provided. A gentle slope revetment block (Japanese Patent Laid-Open No. 2004-27,539) in which the protrusions formed at both ends of the front and rear end surfaces are engaged with each other by the above-mentioned recess when laid and laid, a lower base part, and an intermediate base part And the top surface is from the front edge to the rear edge The upper board part having a low inclination toward the upper board part is integrally formed, and the gap between the left and right ends of the lower board part and the upper board part is used as a flow path of the drawing wave, and the intermediate base part is at least two. A revetment concrete block (Japanese Patent Laid-Open No. 2004-324,219) and the like in which an intermediate flow path is formed between the left and right sides has been proposed.

  And in these conventional covering blocks, in order to ensure the stability and structural strength against the waves of the covering block layer in structures such as revetments constructed using this, the entire outline shape of the block body is usually flat. It is formed in a lump shape whose vertical height (thickness dimension) is relatively large with respect to the size, whereby each covering block has mainly each covering block with respect to the force (wave force) received from the wave. It has a structure that competes with its own weight.

  That is, regarding the wave force acting on each covering block in the covering block layer, as shown in FIG. 7, each covering block 61 laid on the foundation material layer 62 has a foundation material 62a of the foundation material layer 62. Since the vertical vertical wave force (lifting pressure) 63 acting through the gap and the horizontal horizontal wave force 64 act (see FIG. 7A), the covering block layer 65 of the wave lifting pressure 63 is affected. As shown in FIG. 7B, the breakdown depends on the size of the pressure receiving surface 61a on the plane (bottom surface) of each covering block 61, and the destruction of the covering block layer 65 due to the horizontal wave force of the wave is illustrated in FIG. 7 (c), it depends on the size of the pressure-receiving surface 61b of the front end face of each covering block 61. However, in the conventional covering block, the entire contour shape of the block main body is generally a mass. The weight of the block body against the pressure-receiving surface is relatively large It is designed this way so that it can counteract the wave forces acting on each coating block.

  However, in such a conventional covering block, the volume required per covering area is increased in order to gain its weight, and a large lifting pressure acts, so that stability is high at construction sites where waves are severe. In order to ensure that it has a larger mass, especially in order to be able to cope with the extremely large wave force assumed when a typhoon strikes, it is necessary to use a larger weight, which is extremely uneconomical. There is also a problem.

Japanese Patent No. 2,519,173 JP 2004-27,539 A JP 2004-324,219 JP

  Therefore, in view of the problems in the above-described conventional coating block, the present inventors can not only ensure sufficient stability against wave power, but also have excellent economic efficiency and can easily ensure structural strength. As a result of intensive studies, the concrete block main body has an overall contour shape having a frame body portion of the outer peripheral edge portion and a lattice beam portion surrounded by the frame body portion to form at least four openings. By forming the lattice shape and setting the ratio (Ao / Ac) of the total opening area (Ao) to the covering area (Ac) within a predetermined range, the wave acting on each covering block while ensuring the structural strength. The present inventors have found that the lifting pressure can be reduced as much as possible, and sufficient stability against wave power can be secured economically, thereby completing the present invention.

  Accordingly, an object of the present invention is to provide a covering block that can not only ensure sufficient stability against wave force, but also has excellent economic efficiency and can easily ensure structural strength.

  That is, the present invention comprises a block body made of concrete and a plurality of openings penetrating in the thickness direction in the block body, and the block body constitutes a frame body portion constituting an outer peripheral edge portion thereof, The space surrounded by the frame body part is partitioned while crossing each other with beams, and has lattice beam parts that form at least four or more openings, and the entire contour shape is formed in a lattice shape The ratio of the opening area (Ao / Ac) of the sum of the planar areas of the plurality of openings to the covering area (Ac) of the block body (total opening area: Ao) is 0.3 ≦ Ao / Ac ≦ 0.6 It is a covering block characterized by being a range.

  In the present invention, the shape of the block main body is not particularly limited as long as it has a frame body portion and a lattice beam portion, and the overall outline shape is a lattice shape. For example, the planar shape is a triangle, square, rectangle, etc. The shape may be rectangular, hexagonal, pentagonal, or other polygonal, circular, elliptical, oval, or other irregular shapes such as approximately L-shaped, approximately U-shaped, etc., and it is particularly easy to form a plurality of openings. And it is good for the shape which is easy to lay on the basic material layer of a construction site, for example, shapes, such as a rectangular shape.

  Also, the shape of the opening that penetrates in the thickness direction provided in the block main body may be any one that can form a plurality of openings while ensuring the desired shape and structural strength of the block main body. As with the overall contour shape of the block main body, for example, the planar shape thereof is a triangle, a rectangle such as a square or a rectangle, a polygon such as a hexagon or a pentagon, a circle, an ellipse, an oval, or another approximately L-shape, approximately Examples of the shape include irregular shapes such as a U-shape.

  And about the several opening part formed in this block main body, the opening area ratio (Ao / Ac) of the total opening area (Ao) with respect to the covering area (Ac) of a block main body is 0.3 <= Ao / Ac <= 0. .6, preferably 0.3 ≦ Ao / Ac ≦ 0.5. If the opening area ratio (Ao / Ac) is smaller than 0.3, the area of the pressure receiving surface with respect to the lifting pressure of the block main body having a flat shape cannot be reduced to a desired level, and is constructed as a result. On the other hand, when the opening area ratio (Ao / Ac) is larger than 0.6, the desired structure for the block body (ie, the covering block) is reduced. It is difficult to ensure the structural strength of the.

  In the present invention, in order to achieve a desired opening area ratio (Ao / Ac) while ensuring a desired structural strength of the covering block (block body), the block body is a frame that forms the outer peripheral edge of the block body. And a lattice beam part that partitions the space surrounded by the frame part while intersecting each other with a horizontal beam and a vertical beam to form at least four openings, and the overall contour shape is a lattice shape In particular, it is preferable that the overall contour shape is formed in a rectangular lattice shape, and the plurality of openings are formed in a planar rectangular shape. As described above, the outer peripheral edge portion is a frame body portion for ensuring structural strength, and the portion surrounded by the frame body portion and the lattice beam portion are regions for forming a plurality of openings. In particular, the structural strength of the block body and the opening area ratio (Ao / Ac) of the plurality of openings can be achieved. Here, the number of horizontal beams and vertical beams constituting the lattice beam portion can be appropriately determined according to the number and arrangement of a plurality of openings to be formed.

By the way, for the design procedure when building a structure such as a revetment using a specific covering block, the following Hudson equation is generally used for the design wave height.
W = γr · H ³ / {Ns ³ (Sr−1) ³ }
(W: Required weight, γr: Air unit volume weight of the block, H: Wave height used for design calculation, Sr: Specific gravity of the block with respect to sea water, Ns: Stability number: Block shape, damage rate, inclination angle of the covering slope Experimentally obtained based on such factors)
Is used to calculate the weight required for each coating block forming the coating block layer from this wave height, to produce a coating block of the required required weight (W), and to provide a base material under the coating block layer The weight (size) of the base material such as rubble constituting the layer is generally 1/5 to 1/100 W, usually 1/5 based on the required weight (W) of the covering block. Selection of a weight of about 20 to 1/50 W has been performed.

Therefore, it is necessary to design the shape and size of the opening formed in the block body in consideration of the weight (size) of the base material used for construction of a structure such as a seawall. Preferably, the largest one (Db-max.) Of the minimum width dimensions (Db) of each opening is the value of the cube root (V ¹ ) of the block body volume (V). ^{/ 3} ) in the range of 0.15V ^1/3 ≦ Db-max. ≦ 0.5V ^1/3 , more preferably in the range of 0.2V ^1/3 ≦ Db-max. ≦ 0.4V ^1/3 It is good to be. Db-max. Value of the plurality of openings is difficult to achieve 0.15V ^1/3 smaller than a desired opening area ratio (Ao / Ac), on the opposite, 0.5V ^1/3 If it is larger, there is less room for selecting a base material that can be used.

  In consideration of the weight (size) of the base material, in order to achieve a necessary opening area ratio (Ao / Ac), the plurality of openings formed in the block body preferably have the same shape and The length ratio (Da / Db) between the maximum width dimension (Da) and the minimum width dimension (Db) of each opening formed is 1.5 ≦ Da / Db ≦ 10.0. More preferably, the range is 2.0 ≦ Da / Db ≦ 6.0. If the length ratio (Da / Db) is smaller than 1.5, the required opening area ratio (Ao / Ac) is set. It becomes difficult to achieve, and conversely, if it exceeds 10.0, it becomes difficult to maintain the structural strength.

Further, the thickness (Fb) of the block main body in its overall contour shape varies depending on the required weight (W) required for the block main body. to ensure better stability, 0.15V ^1/3 ≦ Fb ≦ 0.4V ^1/3 against preferably the cube root of the block body volume (V) value (V ^1/3) range, and more preferably in the range of 0.2V ^1/3 ≦ Fb ≦ 0.35V ^1/3. Although the lifting force that acts on structures such as revetments constructed when the thickness (Fb) of the overall contour of the block body is less than 0.15V ^1/3 is reduced, the required weight (W) of the block body is reduced. On the other hand, when it becomes larger than 0.4V ^1/3 , the weight per covering area increases as a result, and the economical efficiency is impaired.

Furthermore, in the covering block of the present invention, in order to ensure the installation stability of the block main body, it preferably protrudes downward from the overall contour shape at at least three locations on the lower surface side of the outer peripheral edge of the entire contour shape. Legs are provided.
In addition, in the covering block of the present invention, reinforcing reinforcement may be applied to the block body as necessary, thereby further ensuring structural strength.

  In addition, about the covering block of this invention used when constructing the covering block layer of structures, such as a certain revetment, the shape and magnitude | size do not necessarily have to be the same, Various shapes and magnitude | sizes are not necessarily required. Of course, the coating block layer may be constructed using a plurality of types of coating blocks, and may be used in combination with a coating block having a shape other than the present invention if necessary.

  The covering block of the present invention can not only ensure sufficient stability against wave power, but also has excellent economic efficiency and can easily ensure structural strength.

  Hereinafter, preferred embodiments of the present invention will be specifically described based on examples shown in the accompanying drawings.

  In FIG. 1, a covering block B according to an embodiment of the present invention is shown, and the covering block B has twelve portions penetrating in a thickness direction in a concrete block body 1 having a generally flat outline shape. The opening 2 is provided. The block main body 1 is divided into a plane square-shaped frame body 3 constituting the outer peripheral edge of the block body 1 and a space surrounded by the frame body 3 while intersecting each other by a horizontal beam 4a and a vertical beam 4b. It has lattice beam portions 4 that form twelve planar rectangular openings 2 of the same shape and size, and the overall contour shape is formed in a rectangular lattice shape.

In the covering block B of this embodiment, the volume of the block body 1 is V (m ³ ), the size of one side of the block body 1 having a planar square shape is L (mm), and the thickness is Fb ( mm), the long side dimension (maximum width dimension) of each opening is Da, the short side dimension (minimum width dimension) is Db, the width dimension of the frame 3 is Fa, and its height. The dimension is Fb, and the width dimension of the horizontal beam 4a and the vertical beam 4b constituting the lattice beam portion 4 is Ga, and the height dimension is Gb.
In this embodiment, the width beam Ga and the height beam Gb of the horizontal beam 4a and the vertical beam 4b constituting the lattice beam portion 4 are both designed to be the same size, but differ depending on the horizontal beam 4a and the vertical beam 4b. Of course, the size may be designed.

  Further, the block main body 1 is provided with leg portions 5 projecting downward from the entire contour shape at the four corners thereof, so that the installation stability when laying on the foundation material layer formed at the construction site can be ensured. It is like that.

[Examination example 1]
In the covering block having the shape of the above embodiment, in order to design the shape and size of each opening, the long side dimension (maximum width) with respect to the cube root value (V ^1/3 ) of the volume V of the block body 1 Forming openings with different dimensions (Da) and short side dimensions (minimum width dimension) Db, and considering the stability of the base material, assuming that the size of the base material forming the base material layer is 0.4V ^1/3 did.

  The result will be described with reference to FIG. 2. When the short side dimension Db is 1.0 times or less of the size of the base material 6, it is stable regardless of the size of the long side dimension Da (see FIG. 2 (a)). In addition, if the short side dimension Db exceeds 1.6 times the size of the base material 6, it is unstable regardless of the size of the long side dimension Da (see FIG. 2 (b)), and Even when the short side dimension Db is 1.0 to 1.2 times the size of the base material 6, the short side dimension Db is stable regardless of the size of the long side dimension Da (see FIG. 2C). From this, when the short side dimension Db is 1.0 to 1.2 times the size of the base material 6, the movement of the adjacent base material 6b while being in contact with the focused base material 6a is hindered, Due to the frictional force between these adjacent base materials 6b, the target base material 6a does not flow out of the opening 2 of the block main body 1 or moves in the opening 2 and this attention is paid. It was found that the stability of the base material 6a was ensured.

  From the above results, in order to achieve the required opening area ratio (Ao / Ac), the length ratio (Da / Db) between the maximum width dimension (Da) and the minimum width dimension (Db) of each opening. ) Should be large, but in order to achieve a desired opening area ratio (Ao / Ac) while maintaining structural strength, the length ratio (Da / Db) is usually 1.5 ≦ It has been found that Da / Db ≦ 10.0, preferably 2.0 ≦ Da / Db ≦ 6.0.

[Examination example 2]
The block body has a total weight W equivalent to that of a conventional X-type block (trade name: X-block manufactured by Tetra Co., Ltd.) and has an opening area ratio Ao / Ac = 0.34, Da / Db = 3.4, Db− Create a reduced model assuming max = 0.23V ^1/3 and thickness Fb = 0.27V ^1/3 , and conduct a hydraulic model experiment (stability experiment) to determine the stable number Ns and damage rate (%). Sought the relationship.

The result is as shown in FIG. 3, and the stable number Ns at the damage rate of 1% is about 4.2 in the case of the conventional X-type block, whereas the stable number of the coated block in this examination example 2 Ns is 5.2, and the total weight W of the covering block of the present study example 2 required for forming a covering block layer having the same stability as that of the conventional X-type block with respect to the same wave height is the Hudson equation. 1 / 1.9 [= (4.2 / 5.2) ³ ] = 0.53 times the weight, and as a result, the construction cost ratio of the X-type block is 0.78, and the stable number of coated blocks It has been found that Ns is greatly improved and the economic efficiency is remarkably improved.

Construction Example FIG. 4 shows a structure such as a revetment constructed using the covering block B of the above embodiment, that is, the mound part M1 of the hybrid bank, and FIG. 5 also uses the covering block B of the above embodiment. FIG. 6 shows a structure such as a revetment constructed by using the covering block B of the above embodiment, that is, an inclined revetment M3.

  The coated block of the present invention is extremely useful industrially because it can not only ensure sufficient stability against wave power, it is also economical, and it can easily ensure structural strength.

FIG. 1 is an explanatory perspective view of a covering block according to an embodiment of the present invention. FIG. 2 is an explanatory view showing the relationship between the long side dimension and the short side dimension of the opening in the covering block of the present invention and the rubble constituting the base material layer.

FIG. 3 is a graph showing the relationship between the stable number Ns and the damage rate (%) obtained in the hydraulic model experiment of Study Example 2 of the present invention. Drawing 4 is an explanatory view showing the mound part (structure such as a seawall) of the hybrid bank constructed using covering block B concerning the example of the present invention.

FIG. 5 is an explanatory view showing an artificial reef (structure such as a seawall) constructed using the covering block B according to the embodiment of the present invention. FIG. 6 is an explanatory diagram showing an inclined revetment (structure such as a revetment) constructed using the covering block B according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram for explaining wave forces (horizontal wave force and lifting pressure) acting on the covering block.

Explanation of symbols

  B ... Covering block, 1 ... Block body, 2 ... Opening, 3 ... Frame body part, 4 ... Grid beam part, 4a ... Cross beam, 4b ... Vertical beam, 5 ... Leg part, 6 ... Base material, 6a ... Foundation material, 6b ... Foundation material adjacent to the foundation material 6a while in contact.

Claims (5)

It is equipped with a block body made of concrete and a plurality of openings that penetrate the block body in its thickness direction,
The block main body includes a frame body portion constituting an outer peripheral edge portion thereof, and a lattice beam portion that partitions at least four openings by partitioning a space surrounded by the frame body portion while crossing each other with a beam. And the entire contour shape is formed in a lattice shape,
The ratio of the opening area ratio (Ao / Ac) of the sum of the planar areas of the plurality of openings (total opening area: Ao) to the covering area (Ac) of the block body is in the range of 0.3 ≦ Ao / Ac ≦ 0.6. The covering block characterized by being. Among the plurality of openings formed in the block body, the largest one (Db-max.) Of the minimum width dimensions (Db) of each opening is the value of the cube root of the block body volume (V). The coated block according to claim 1, wherein the coated block has a range of 0.15V ^1/3 ≤ Db-max. ≤ 0.5V ^1/3 with respect to (V ^1/3 ).   The plurality of openings formed in the block body are formed in the same shape and size as each other, and the length ratio (Da / Db) between the maximum width dimension (Da) and the minimum width dimension (Db) of each opening. ) Is in the range of 1.5 ≦ Da / Db ≦ 10.0. The block body has a thickness (Fb) in the overall contour shape of 0.15 V ^1/3 ≦ Fb ≦ 0.4 V ^{1 with} respect to the cube root value (V ^1/3 ) of the block body volume (V). The covering block according to any one of claims 1 to 3, which is in a range of ³ .   The covering block according to any one of claims 1 to 4, wherein the block main body is provided with leg portions projecting downward from the overall contour shape at at least three locations on the lower surface side of the outer peripheral edge in the overall contour shape.