Remaining formwork

Abstract

The purpose of this invention is to provide a remaining formwork that allows work to proceed more quickly when attempting to install it before pouring concrete to form a dam or weir, especially when attempting to install it at approximately right angles on the sloping areas at the left and right ends of the dam or weir. [Solution] The problem was solved by the remaining formwork (1), which is a formwork used when pouring concrete and is left in place after the concrete has hardened, and which comprises a concrete slab (2) with a polygonal outer shape, a plurality of rod-shaped or column-shaped pieces of wood (3) of approximately the same shape arranged in parallel on one side of the concrete slab (2), and fastening devices (4) for fastening each of the plurality of pieces of wood (3) to the concrete slab (2), with the same end side of the plurality of pieces of wood (3) protruding beyond one side of the concrete slab (2).

Description

[Technical Field]

[0001] This invention relates to formwork used in constructing concrete structures, which is left as part of the structure without being removed after the concrete is poured. [Background technology]

[0002] In typical concrete construction, the formwork is dismantled and removed after the concrete has hardened, but with residual formwork, this process is not necessary. As a result, residual formwork shortens construction time, reduces labor costs and labor, and reduces construction waste. In addition, because it can be manufactured in advance as a precast product in a factory, the quality is consistent and stable, and by adding design elements, it can also be used as decorative formwork to achieve a beautiful finish.

[0003] For example, Patent Document 1 discloses a continuous sheet of wood in the form of a plank, in which a number of square timbers or drums of approximately the same dimensions made from undried wood are arranged in parallel in the longitudinal direction in the same direction, with the opposing longitudinal cut surfaces of the different pieces of wood being attached together with a predetermined pressing force; dowels embedded in the cut surfaces of the square timbers or drums on one side of the continuous sheet of wood at approximately equal intervals in the longitudinal direction at a predetermined density; and a remaining formwork which is cast into the one side of the continuous sheet of wood and which becomes one with the continuous sheet of wood by the dowels when hardened. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-177046 Summary of the Invention [Problem to be solved by the invention]

[0005] In the examples of the remaining formwork of Patent Document 1, a continuous wooden board and a concrete slab cast on one side of the continuous wooden board, both of which are 1 m wide and aligned on both the left and right sides, allow for the installation of multiple remaining formwork pieces so that they are approximately parallel to a slope such as a hillside. However, when constructing a dam or weir in a river or valley, the soft ground of the river or valley is excavated to expose the solid bedrock supporting the dam or weir, and the remaining formwork is installed before pouring the concrete for the dam or weir. Especially when installing the remaining formwork at the left and right ends of the dam or weir, the remaining formwork must be positioned approximately perpendicular to the inclined bedrock. However, excavating the bedrock to fit the shape of the remaining formwork of Patent Document 1 and cutting the continuous wooden board and concrete slab of the remaining formwork of Patent Document 1 to fit the shape of the bedrock is a laborious task that can delay the construction period.

[0006] Therefore, the purpose of this invention is to provide a remaining formwork that allows work to proceed more quickly when attempting to install it before pouring the concrete that will become a dam or weir, especially when attempting to install it at approximately right angles on the sloping areas at the left and right ends of a dam or weir. [Means for solving the problem]

[0007] [1] That is, the remaining formwork disclosed in the present application is a remaining formwork (1) that remains after the concrete has hardened, among the formwork used when pouring concrete, and is characterized in that it comprises a concrete slab (2) having a polygonal outer shape, a plurality of rod-shaped or column-shaped wooden pieces (3) of approximately the same shape arranged in parallel on one side of the concrete slab (2), and fastening devices (4) that fasten each of the plurality of wooden pieces (3) to the concrete slab (2), and the same one end side of the plurality of wooden pieces (3) protrudes beyond one side of the concrete slab (2).

[0008] [2] The remaining formwork (1) according to [1] is characterized in that the concrete plate (2) is approximately rectangular or approximately square.

[0009] [3] The remaining formwork (1) described in [2] is characterized in that the longitudinal length of the wooden piece (3) is 1.2 to 3 times the width of the concrete plate (2), which is in the same direction as the longitudinal direction of the wooden piece.

[0010] [4] The remaining formwork (1) described in either [1] or [2] is characterized in that the concrete plate (2) has a plurality of reinforcing bars arranged in a lattice pattern inside it.

[0011] [5] The remaining formwork (1) described in either [1] or [2] is characterized in that the concrete slab (2) has connecting bars (5) erected on the other side opposite to the side on which the plurality of wooden pieces (3) are arranged, to connect with the concrete to be poured. [Effects of the Invention]

[0012] The remaining formwork of this invention allows work to proceed more quickly when installing it before pouring the concrete that will become a dam or weir, especially when installing it at approximately right angles on the slopes at both ends of the dam or weir. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view showing a remaining formwork according to a first embodiment of the present invention; FIG. [Figure 2] FIG. 2 is another perspective view of the remaining formwork according to the first embodiment of the present invention; [Figure 3] This is a cross section taken along line AA in FIG. [Figure 4] 1 is a perspective view showing the state in which the remaining formwork according to the first embodiment of the present invention is used for a dam. FIG. [Figure 5] FIG. 5 is an enlarged view of the circular portion in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] The remaining formwork according to the embodiment of the present invention will be described in detail below with reference to the drawings. The embodiment described below is a preferred example for carrying out the present invention, and therefore various technical limitations are imposed. However, the present invention is not limited to this embodiment unless otherwise specified in the following description. Furthermore, the up-down and left-right directions in the description refer to the up-down and left-right directions in Figures 1, 2, and 4. Furthermore, ranges indicated using the symbol "~" include the upper and lower limits.

[0015] Below, a remaining formwork according to an embodiment of the present invention will be described with reference to Figures 1 to 5. Figure 1 is one perspective view showing a remaining formwork according to a first embodiment of the present invention. Figure 2 is another perspective view showing a remaining formwork according to the first embodiment of the present invention. Figure 3 is a cross section taken along line AA in Figure 1. Figure 4 is a perspective view showing the remaining formwork according to the first embodiment of the present invention in use when used for a dam. Figure 5 is an enlarged view of the circular portion in Figure 4.

[0016] 1 to 5, the remaining formwork 1 of this embodiment includes a concrete slab 2, a plurality of wooden pieces 3, and fastening devices 4. The remaining formwork 1 is formed by fastening the concrete slab 2 and the plurality of wooden pieces 3 together with the fastening devices 4.

[0017] The concrete slab 2 is a component made of concrete and has a polygonal outer shape. Because concrete has excellent durability and strength, the concrete slab 2 functions as a formwork in conjunction with multiple pieces of wood 3 when pouring the fluid fresh concrete that will become a dam or weir. Since multiple concrete slabs 2 are arranged lengthwise and widthwise to be used as a formwork, it is preferable that the concrete slabs 2 have a polygonal shape that can fill a plane when multiple pieces are laid out in a flat pattern. Specific polygonal shapes that can fill a plane when multiple pieces are laid out in a flat pattern are preferably approximately equilateral triangles, approximately rectangles, approximately squares, approximately parallelograms, approximately rhombus, approximately regular hexagons, etc., and more preferably approximately rectangular, approximately squares, approximately parallelograms, or approximately rhombus-shaped quadrilaterals in terms of ease of manufacturing, transportation, and installation. Furthermore, the concrete plate 2 does not necessarily have to be a polygonal shape that can be laid out flat when multiple concrete plates 2 are laid out flat, and even if some gaps occur when multiple concrete plates 2 are laid out flat, the gaps can be filled with one end of multiple pieces of wood 3 that protrude beyond one side of the concrete plate 2.

[0018] The dimensions of the concrete slab 2 can vary, but from the standpoint of ease of manufacture, transportation, and installation, a rectangular shape with a width of 500 to 2000 mm and a height of 500 to 2000 mm is preferred. Specifically, for example, a roughly rectangular shape with a width of approximately 2000 mm and a height of approximately 1000 mm is preferred, or a roughly square shape with a width of approximately 1000 mm and a height of approximately 1000 mm is preferred.

[0019] The concrete used to make the concrete slab 2 is made from cement, water, aggregates such as sand and gravel, and admixtures mixed as needed, and is not particularly limited in terms of its specific quality or amount as long as it has the required durability and strength as a formwork.

[0020] It is preferable that the concrete slab 2 has a plurality of reinforcing bars arranged in a lattice pattern inside it. Concrete has excellent compressive strength but is weak against tensile and bending forces, so by having a plurality of reinforcing bars that are strong against tensile and bending forces, it is possible to create a structure that is strong not only against compression but also against tension and bending. For example, the plurality of reinforcing bars are arranged in a lattice pattern at intervals of 100 to 200 mm inside the concrete slab 2. Therefore, for example, if the concrete slab 2 is approximately square, with both width and height lengths of approximately 1000 mm, then 6 to 11 reinforcing bars will be arranged in each of the left and right directions and the up and down directions.

[0021] The wooden pieces 3 are rod- or column-shaped members arranged on one surface of the concrete slab 2. A plurality of the wooden pieces 3 having approximately the same shape are arranged in parallel. The same end of each of the wooden pieces 3 protrudes beyond one side of the concrete slab 2. Because the wooden pieces 3 have this configuration, and in particular because the same end of each of the wooden pieces 3 protrudes beyond one side of the concrete slab 2, when the wooden pieces 3 are to be installed before pouring the concrete that will become a dam or weir, particularly when the wooden pieces are to be installed at approximately right angles at sloping locations on the left and right ends of a dam or weir, they can be quickly processed to fit the sloping location by cutting only the wooden pieces 3 without cutting the concrete slab 2.

[0022] 1 to 5, in this embodiment, each piece of wood 3 is a rectangular prism-shaped piece of lumber, but in other embodiments, cylindrical logs, or pieces of wood made by cutting off two sides of a log, etc., may also be used. In this invention, if the pieces of wood 3 are square lumber cut to the same dimensions, as in this embodiment, they will have the same shape. However, if the pieces of wood 3 are made by removing branches and leaves from the trunks or thick branches of felled trees and peeling or leaving the bark intact, while maintaining their round shape, they will not necessarily have exactly the same shape, and so shapes that can be considered to be roughly the same are also included.

[0023] Each piece of wood 3 is provided with a through-hole 31 that penetrates the thickness of the wood, which is the front-to-back direction in Figures 1 and 2. As will be described later, a part of a fastening device 4 is inserted into the through-hole 31 to fasten each piece of wood 3 to the concrete slab 2. In this embodiment, eight through-holes 31 are drilled along the length of each piece of wood 3, but the number is of course not limited to this.

[0024] The type of wood 3 is preferably cedar, cypress, red pine, Japanese cypress, zelkova, etc. Furthermore, thinned wood obtained by thinning out some of the trees in a forest can be effectively used as the wood 3.

[0025] As shown in Figures 1 and 2, in this embodiment, eleven pieces of wood 3 are arranged in parallel so that their longitudinal directions are approximately parallel, but of course, in other embodiments, the number of pieces of wood 3 can be changed.

[0026] The length of the wooden piece 3 in the longitudinal direction is preferably 1.2 to 3 times, and more preferably 1.5 to 2.5 times, the length of the concrete slab 2 in the width direction, which is the same direction as the longitudinal direction of the wooden piece 3. When the ratio is within this range, it is possible to cut only the wooden piece 3 without cutting the concrete slab 2 according to the inclination angle of the sloped portions at the left and right ends of the dam or weir, thereby enabling quick processing and ultimately shortening the overall construction period. As shown in Figures 1 and 2, in this embodiment, the length of the wooden piece 3 in the longitudinal direction, which is the left-right direction, is twice the length of the concrete slab 2 in the width direction, which is the same direction as the longitudinal direction of the wooden piece 3.

[0027] Furthermore, since the plurality of wooden pieces 3 are arranged in parallel, the sum of the widthwise lengths of each wooden piece 3 (i.e., the vertical length of the plurality of wooden pieces 3 shown in FIGS. 1 and 2 ) is preferably approximately the same as the height of the concrete slab 2. Since the vertical lengths of the plurality of wooden pieces 3 and the height of the concrete slab 2 are approximately the same, as shown in FIG. 4 , the plurality of remaining formwork 1 can be used as formwork by being laid out closely together with almost no gaps when arranged vertically. As shown in FIGS. 4 and 5 , the remaining formwork arranged at the sloping locations on the left and right ends of the dam or weir is the remaining formwork 1 of the present invention. However, the remaining formwork arranged at locations other than the left and right ends of the dam or weir, such as the center of the dam or weir, does not necessarily have to be the remaining formwork 1 of the present invention. Other remaining formwork B, in which the widthwise length of the concrete slab 2 (i.e., the horizontal length) and the longitudinal length of the plurality of wooden pieces 3 are approximately the same, can be used.

[0028] The fastening devices 4 are components that fasten the plurality of wooden pieces 3 to the concrete slab 2. The fastening devices 4 can secure the plurality of wooden pieces 3 to the concrete slab 2 so that they cannot be separated when pouring concrete to form a dam or weir. As shown in FIG. 3 , in this embodiment, the fastening devices 4 are bolts 41 that are inserted into the through-holes 31 and have one end embedded in the concrete slab 2, and nuts 42 that are screwed into the other end of the Volvo 1 through the through-holes 31. However, in other embodiments, screws, pins, dowels, etc. can also be used as long as they can secure the plurality of wooden pieces 3 to the concrete slab 2 so that they cannot be separated.

[0029] The connecting bars 5 are erected on the other side of the concrete slab 2 opposite the side on which the wooden pieces 3 are placed, and are connected to the poured concrete. The connecting bars 5 connect the concrete slab 2 to a dam or weir formed from the poured concrete, preventing the concrete slab 2 from peeling off from the dam or weir. As shown in Figures 2 and 3, in this embodiment, the connecting bars 5 are hook-shaped or J-shaped, and four connecting bars 5 are erected near the four corners of the other side of the concrete slab 2. However, in other embodiments, the connecting bars 5 may be I-shaped, L-shaped, or T-shaped, or may be one, two, three, or more. The connecting bars 5 are preferably made of a metal such as iron or stainless steel.

[0030] The remaining formwork 1 of the present invention is used as follows.

[0031] First, the soft ground of the river or valley is excavated to expose the solid bedrock that will support the dam D. Before pouring the concrete that will become the dam D, the remaining formwork 1 of the present invention and another remaining formwork B, whose length in the width direction (left and right) of the concrete slab 2 is approximately the same as the length in the longitudinal direction of the multiple timber pieces 3, are installed to form the formwork. At this time, the remaining formwork B is installed near the center of the dam D, and since the bedrock is inclined at the left and right ends of the dam D, one end of the multiple timber pieces 3 that protrude beyond one side of the concrete slab 2 in the remaining formwork 1 is cut to follow the angle of inclination of the inclined portion and installed at approximately right angles to the inclined portion. In this way, since only one end of the multiple timber pieces 3 needs to be cut, the remaining formwork 1 allows the work to proceed quickly.

[0032] Then, after a pair of formworks is formed using the multiple remaining formworks B and the remaining formworks 1, concrete that will become dam D is poured between the formworks. After the concrete hardens, some of the formwork is removed, leaving behind the multiple remaining formworks B and 1, as shown in Figures 4 and 5. Note that even if one end of the multiple wooden pieces 3 that protrude from one side of the concrete slab 2 in the remaining formwork 1 is cut off as shown in Figure 5, if a gap occurs between the sloping part of the bedrock and the multiple wooden pieces 3, the cut pieces can be reused and fixed to fill the gap. [Explanation of symbols]

[0033] 1. Remaining formwork 2. Concrete plate 3...wood 31...Through hole 4. Locking device 41 volts 42 Nut 5. Splice D···Dam B. Other remaining formwork

Claims

1. A remaining formwork that remains after the concrete has hardened among the formwork used when pouring concrete, A concrete plate with a polygonal shape, A plurality of rod-shaped or column-shaped wooden pieces having substantially the same shape and arranged in parallel on one surface of the concrete plate; a fastening device for fastening each of the plurality of wooden pieces to the concrete plate; The same end of each of the plurality of wooden pieces protrudes from one side of the concrete plate. Remaining formwork characterized by:

2. 2. The remaining formwork according to claim 1, wherein the concrete slab is approximately rectangular or approximately square.

3. The remaining formwork described in claim 2, characterized in that the longitudinal length of the wooden piece is 1.2 to 3 times the width of the concrete plate, which is in the same direction as the longitudinal direction of the wooden piece.

4. 3. The remaining formwork according to claim 1, wherein the concrete slab has a plurality of reinforcing bars arranged in a lattice pattern inside the slab.

5. The remaining formwork described in either claim 1 or claim 2, characterized in that on the other side of the concrete slab opposite the side on which the plurality of wooden pieces are arranged, connecting reinforcement bars are erected to connect with the concrete to be poured.

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