JP7430013B1 - Precast aerated mixed lightweight soil - Google Patents

Abstract

[Problem] To provide a precast foamed lightweight soil that can be easily lifted even if it is formed into a block and does not undergo deformation during lifting. [Solution] A block body 2 formed by curing a mixture of cement, aggregate, fiber material, and foaming agent with water in a mold, and a metal reinforcement arranged inside the block body 2. A mesh plate 3 is provided, and a plurality of anchors 4 for lifting tools are embedded in the upper part of the two blocks while being connected to the mesh plate 3 in order to enable the lifting of the block body 2. [Selection diagram] Figure 2

Description

The present invention relates to precast aerated mixed lightweight soil that can be suitably used for road embankments and the like.

BACKGROUND ART Foam mixed lightweight soil (FCB) has been conventionally used as a construction method for constructing road embankments and the like. In the general FCB construction method, cement, aggregate, foaming agent, and water are mixed at the construction site to form a mixture, which is then hardened at the construction site to construct an embankment. However, kneaded aerated lightweight soil is susceptible to water until it hardens, and there is a problem in that it cannot be used in rainy weather or in areas with water. In addition, kneaded air-mixed lightweight soil contains many air bubbles, has lower strength than normal concrete, and has the problem of being susceptible to weathering and deterioration before it hardens at the construction site. Furthermore, on-site manufacturing and construction requires a large number of manpower and skilled workers, and there is a need for on-site labor saving and improved efficiency.

In order to solve these problems, Patent Document 1 discloses a conventional technique in which aerated lightweight soil is formed into blocks at a factory, and the blocks of aerated lightweight soil are stacked at a construction site to form an embankment. There is. With this method, the materials are kneaded, cured, and hardened in the factory, making quality control easy.Since the material is a hardened block, it is not affected by the climate on site, and requires less manpower. This has the advantage of saving labor and simplifying construction.

Japanese Patent Application Publication No. 10-280414

When constructing an embankment using blocks of lightweight soil mixed with air bubbles, it is necessary to move the blocks to the construction site or to the stacking area at the construction site, and the blocks must be lifted for this purpose. To deal with this lifting, in the conventional technique described in Patent Document 1, it is necessary to wrap a long lifting material such as a wire rope or chain around the block body and lift it using a crane or the like.

However, the blocks are large (1000 x 2000 x 500 mm) and heavy as they contain a large amount of cement, making it difficult to wrap wire ropes or chains around them, which poses a major hindrance to lifting operations. Further, when the block body is lifted, the block body may be bent or deformed such as cracks. This is because the strength of the block body is not strong enough to withstand lifting, or the lifting force does not act uniformly on the entire block body.

The present invention has been made in consideration of the above-mentioned problems, and it is possible to easily lift even lightweight clay mixed with air bubbles formed into blocks, and it does not deform during lifting. The purpose is to provide precast aerated mixed lightweight soil.

The precast aerated lightweight soil of the present invention consists of a block body formed by curing a mixture of cement, aggregate, fiber material, and foaming agent in water in a mold, and reinforcement arranged inside the block body. and a plurality of hanging anchors connected to the mesh plate and buried in the upper part of the block body in order to enable the lifting of the block body . The tool anchor is characterized in that it includes an anchor tip plate embedded in the block body in order to increase the pulling resistance from the block body .

The block body has a rectangular parallelepiped shape, and the mesh plate has a rectangular shape similar to one side of the rectangular parallelepiped. It is characterized in that it is connected at a certain point and has a removable hanging device attached to its upper part.
Further, the mesh plate is characterized in that reinforcement is arranged at upper and lower positions inside the block body.
Further, the block body is characterized in that the surface thereof is coated with a resin emulsion for suppressing dry cracking.

According to the precast foam-mixed lightweight soil of the present invention, since it is provided with the lifting tool anchor 4, even if it is formed into a block shape, it can be easily lifted. Furthermore, since the metal mesh plate 3 is provided inside, there is no deformation such as bending, deflection, or cracking even when the device is lifted, and the device can be lifted reliably.

FIG. 1 is a perspective view showing an embodiment of precast aerated mixed lightweight soil. FIG. 2 is a plan view of precast aerated lightweight soil. 3 is a sectional view taken along line CC in FIG. 2. FIG. (A) is a sectional view taken along the line AA in FIG. 2, and (B) is a sectional view taken along the line BB. It is a sectional view showing the arrangement part of the anchor for hanging tools. It is a sectional view showing a state where a hanging tool is connected to an anchor for hanging tools. FIG. 3 is a perspective view showing another embodiment of precast aerated mixed lightweight soil.

1 to 6 show a precast aerated lightweight soil 1 according to an embodiment of the present invention. FIG. 1 is a perspective view of precast aerated lightweight soil 1, FIG. 2 is a plan view of precast aerated lightweight soil 1, FIG. 3 is a sectional view taken along line CC in FIG. 2, and FIG. 4(A) is A-- in FIG. FIG. 5 is a sectional view showing the arrangement of the hanging anchor, and FIG. 6 is a front view showing the usage state of the hanging anchor.

As shown in FIGS. 1 to 4, the precast foam-mixed lightweight soil 1 includes a block body 2, a mesh plate 3, and a hanging anchor 4.

The block body 2 has a rectangular parallelepiped outer shape. The block body 2 having a rectangular parallelepiped shape is formed to have a size of, for example, 1000 x 2000 x 500 mm. The shape of the block body 2 can be formed into a triangular three-dimensional shape, a hexagonal three-dimensional shape, an octagonal three-dimensional shape, or other three-dimensional shapes, and the size can also be changed as appropriate.

As shown in FIGS. 2 to 4, the mesh plate 3 is a metal mesh plate formed by assembling rust-proofed metal wires (for example, stainless steel wires) into a net shape and welding them together. The mesh plate 3 is formed to have a shape similar to the outer shape of the block body 2 and somewhat smaller than the outer shape of the block body 2. In the illustrated example, since the block body 2 is a rectangular parallelepiped, it is formed into a quadrangle similar to one surface of this rectangular parallelepiped. Moreover, the mesh plate 3 is reinforced at the upper and lower sides inside the block body 2, as shown by symbols 3a and 3b.

In this way, the mesh plate 3 is similar to the block body 2, and by arranging mesh plate 3 vertically, it is possible to cope with the bending moment due to the block body 2's own weight that is applied during lifting. Bending can be suppressed. It is preferable that the mesh plate 3 is reinforced at upper and lower positions inside the block body 2, but it may also be reinforced only on the upper side depending on the size and weight of the block body 2.

The suspension anchor 4 is used to enable the block body 2 to be lifted. The hanging anchor 4 is embedded in the upper part of the block body 2 while being connected to the upper mesh plate 3a. The lifting tool anchor 4 is arranged at a position where the load is least applied when lifting the block body 2. Therefore, in this embodiment, four suspender anchors 4 are used, each of which is connected by welding or the like to an intersection of metal wires on the inner side of the upper mesh plate 3a.

The hanging tool anchor 4 is buried in the block body 2, and in this buried state, the hanging tool 13 (see FIG. 6) is removably connected to the hanging tool anchor 4. FIG. 5 shows the hanging tool anchor 4 of this embodiment. The hanging anchor 4 includes an anchor body 8 consisting of a bolt with a male thread formed over its entire length extending in the vertical direction, an anchor tip plate 9 and a positioning nut 10 attached to the lower end in the length direction of the anchor body 8. The entire structure is embedded in the block body 2. Anchor tip plate 9 is a member for increasing the pull-out resistance of hanging tool anchor 4, and positioning nut 10 is a member for fixing anchor body 8 and anchor tip plate 9 in a predetermined position.

In this embodiment, a part (upper end portion) of the hanging tool anchor 4 protrudes from the upper end surface of the block body 2 . That is, as shown in FIG. 5, the upper end portion 8a of the anchor body 8 of the hanging anchor 4 protrudes from the upper end surface of the block body 2 by a predetermined length (for example, 20 to 30 mm). As shown in FIG. 6, a hanging tool 13 is removably connected to the upper end portion 8a that protrudes in this way. The hanging tool 13 is made of an eye nut, and is connected to the upper end 8a of the anchor body 8 via a washer 14 and a spring washer 15. The block body 2 can be lifted by connecting the hanging tools 13 to four hanging tool anchors 4.

As shown in FIGS. 3 and 4, in this embodiment, cover thickness spacers 6 are arranged. The cover thickness spacer 6 is a member for arranging the upper and lower mesh plates 3a, 3b at a predetermined depth (for example, 40 to 60 mm) of the block body 2, and is arranged at equal positions with respect to the upper and lower mesh plates 3a, 3b. Six pieces are placed. By providing the cover thickness spacer 6, the mesh plates 3a, 3b can be arranged on the block body 2 to a depth of, for example, 50 mm. Mortar or the like can be used as the material for the cover spacer.

The block body 2 will be explained.
The block body 2 is produced by kneading cement, aggregate, fiber material, and foaming agent with water. As for the physical properties of the block body 2 to be produced, the compressive strength after curing of the block body 2 is 0.3 to 2 N/mm ² , the unit volume weight is 3 to 1.2 kN/m ³ , and the blending ratio of air is 40 to 2. 70% is good. Table 1 shows an example of the blending amount of the block body 2 to satisfy these physical properties.

As the cement, ordinary Portland cement or blast furnace cement type B can be used, and as the aggregate, river sand, mountain sand, calcium carbonate powder, or glass powder can be used. As water, industrial water or tap water can be used. As the fiber material, synthetic fibers or steel fibers can be used. Among these, as the synthetic fiber, for example, polypropylene resin having the trade name "Balchip" can be used. By mixing the fiber material, the bending strength and tensile strength of the block body 2 can be increased, and corner chipping and cracking due to impacts during transportation can be suppressed. As the foaming agent, surfactant-based foaming agents and protein-based foaming agents can be used. Among these, as the surfactant-based foaming agent, for example, an alkyl sulfate ester surfactant having the trade name "Geoheart" can be used.

"Resin" in the rightmost column of Table 1 is a resin emulsion that is applied to the surface of the block body 2 after the block body 2 is manufactured. can be used. By applying the resin emulsion to the entire surface of the block body 2, durability is imparted to the block body 2, and weathering and deterioration of the block body 2 during storage can be prevented. In addition, the wear resistance of the block body 2 is improved.

Since the precast foam-mixed lightweight soil 1 of this embodiment is provided with a lifting tool anchor 4 to enable lifting, even if it is formed into a block shape, it can be easily lifted. In addition, since the inside is provided with a metal mesh plate 3 to provide strength, there is no deformation such as bending, deflection, or cracking even when it is lifted, and it can be lifted reliably.

Precast aerated mixed lightweight soil 1 is manufactured by kneading cement, aggregate, and water to create a cement slurry, mixing fiber material with this cement slurry, and then foaming it with foaming agent powder and diluent. The foaming agent is mixed and kneaded . On the other hand, a metal mesh plate connected with a hanging anchor is set in a steel formwork. Then, the block body 2 is produced by filling the kneaded material into a mold and curing it. After curing for several days, the block body 2 is removed from the mold and taken out. After that, resin is applied to the surface of the block body 2.

All of the above processes are carried out at the factory, allowing for temperature control and stable quality control. In addition, since it is hardened into a block body in a factory, it can avoid the negative effects of water such as rainwater, unlike construction on site, and can prevent weathering and deterioration. Furthermore, it is possible to improve efficiency and save labor.

FIG. 7 shows another embodiment of a precast aerated mixed lightweight soil 1A. In this precast foam-mixed lightweight soil 1A, the hanging anchor 4 disposed in the block body 2 is buried in the block body 2, and the upper end portion does not protrude from the block body 2. A female thread 16 is formed on the inner surface of the hanging tool anchor 4, and a hanging tool (not shown) is removably connected via the female thread 16. This makes it possible to lift the block body 1A.

An example of the method for constructing the precast aerated lightweight soil of the present invention will be described. First, a hanging tool is connected to the block-shaped precast foam mixed lightweight soil 1 produced in a factory, and the precast foam mixed lightweight soil 1 is lifted up by a crane or the like via the hanging tool and arranged on the site. A mixture of cement, aggregate, fiber material, and foaming agent kneaded with water is filled between adjacent precast foamed lightweight soils 1 and hardened to join the adjacent precast foamed lightweight soils 1. This will form the lower embankment.

Next, after removing the hanging tool from the precast aerated lightweight soil 1, a mixture of cement, aggregate, fiber material, and a foaming agent mixed with water is cast onto the lower embankment. Before the kneaded material starts to harden, the precast aerated lightweight clay 1 connected to the hanger is arranged on top of the kneaded material, and the adjacent precast aerated lightweight clay 1 are joined together. This will form the upper embankment.

Furthermore, by repeating the above-mentioned process for forming the upper embankment, an embankment of the desired height is formed, and a road or the like is formed on the uppermost embankment.

According to such a construction method, it is easy to lift the block-shaped precast foam-mixed lightweight soil, so the embankment can be easily formed.

1, 1A Precast foam mixed lightweight soil 2 Block body 3 Mesh plate 3a Upper mesh plate 3b Lower mesh plate 4 Hanging tool anchor 6 Cover thickness spacer 8 Anchor body 9 Anchor tip plate 10 Positioning nut 13 Hanging tool 14 Washer 16 Female screw

Claims (4)

A block body formed by curing a mixture of cement, aggregate , fiber material, and foaming agent with water in a mold;
a metal mesh plate reinforced inside the block body;
In order to enable the block body to be lifted, a plurality of lifting tool anchors are embedded in the upper part of the block body while being connected to the mesh plate,
The precast foam-mixed lightweight soil is characterized in that the hanging tool anchor is provided with an anchor tip plate embedded in the block body in order to increase resistance to pulling out from the block body . The block body has a rectangular parallelepiped shape, and the mesh plate has a rectangular shape similar to one side of the rectangular parallelepiped. 2. The precast aerated lightweight soil according to claim 1, wherein the precast foam-mixed lightweight soil is connected at a certain point and has a hanging device attached to and detachable from the upper portion thereof. The precast foam-mixed lightweight soil according to claim 1 or 2, wherein the mesh plates are reinforced at upper and lower positions inside the block body. The precast aerated lightweight soil according to claim 1 , wherein a resin emulsion for suppressing dry cracking is applied to the surface of the block body.

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