JPS6233861Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a joint cutting material that is buried in a concrete placement surface such as a roof or wall of a building, a road surface, a parking lot, etc., and divides the concrete surface into small parts.

As is well known, the surface on which concrete is poured expands and contracts due to changes in the temperature of the outside air, so if concrete is poured continuously, countless cracks may occur. Joint cutting material is used to prevent the occurrence of cracks. For example, concrete is poured into each square of joint cutting material arranged in a grid pattern, dividing the concrete into small area sections, and preventing the occurrence of cracks. The cut parts absorb the expansion and contraction of the concrete.

Even if the expansion and contraction of the concrete is absorbed by the joint cutting material, when the concrete actually shrinks, a small gap is created between the side of the joint cutting material and the concrete, and rainwater may flow in through this gap and cause water leakage. There is. For this reason, in the past, an adhesive layer made of butyl rubber or unvulcanized rubber was placed on the side of the front frame, which is the main component of the joint cutting material, to prevent the formation of gaps and prevent water leakage, such as rainwater. .

However, butyl rubber and non-vulcanized rubber are expensive and are not practical as adhesive layers for joint cutting materials. Also, if exposed to the outside air for a long period of time, it will deteriorate and lose its sealing effect.

This proposal was proposed in view of the above, and by providing a sealing layer on the outer surface of the front frame that expands when it contains water and closes the gap, even if the concrete surface gets wet with water, the joint cutting material and the concrete will remain intact. The object of the present invention is to provide a joint cutting material that can be sealed to prevent water from flowing in from the boundary portion of the joint, thereby preventing troubles such as water leakage.

The configuration of the present invention will be explained below based on the embodiments shown in the drawings.

The joint cutting material 1 consists of a long base frame 2 and a similarly long front frame 3 attached to the base frame 2. Base frame 2
is preferably molded from a synthetic resin material, and its cross-sectional shape is trapezoidal with good stability. A pair of cut grooves 4, 4 are formed perpendicularly from the top surface of the base frame 2 at symmetrical positions in the longitudinal direction. Note that the cut grooves 4, 4 can be formed by simply making cuts in the base frame 2. Further, a known adhesive 5 is attached to the bottom surface of the base frame 2, and this adhesive 5 is always covered with a release paper 6.

On the other hand, the front frame 3 is molded from a hard or semi-hard synthetic resin material, and has a pair of side plates 7 located on both sides in the longitudinal direction and insertable into the cut grooves 4, 4 of the base frame 2. , 7, and an exposed plate portion 8 that connects the upper ends of both side plates 7, 7, and is formed in a downward elongated U-shape in cross section. The cut grooves 4 can hold the side plates 7, 7 inserted therein at an arbitrary height position by frictional force. The side plates 7, 7 have horizontally long locking groove members 9, 9 with an open upper surface projecting from the outer surfaces of the intermediate portions in the height direction, and the outer surfaces of the side plates 7, 7. a sealing layer 10,
10 are provided in the longitudinal direction.

The sealing layer 10 is made of a material that expands in volume when it contains water, such as a polyolefin-vinyl resin copolymer having a hydrophilic group such as a polyethylene vinyl acetate copolymer, and has an appropriate thickness (e.g. 1~2m/m). To provide such a seal layer 10 on the outer surface of the front frame 3,
For example, a polyethylene vinyl acetate copolymer emulsion liquid may be applied to the outer surface and dried to form a film, or a film formed in advance may be pasted.

For example, when constructing the rooftop of a building, the main joint cut material 1 having the above structure is placed on the upper surface of the waterproof layer b applied on the concrete slab a, in a square shape, parallel shape, etc., as appropriate. Then, the release paper 6 on the bottom surface of the base frame 2 is peeled off to expose the adhesive 5, and the base frame 2 is fixed on the waterproof layer b using this adhesive layer.

After fixing the base frame 2 on the waterproof layer b in this way, the height is adjusted by raising and lowering the front frame 3,
Adhesive 11 is dropped onto the upper ends of the cut grooves 4, 4 to integrally fix the front frame 3 and the base frame 2.

Then, if concrete is poured up to the height position c of the exposed plate part 8 of the front frame 3, the work of burying the grain cut material 1 is completed.

When the concrete poured in this way hardens, the front frame 3 shrinks during curing and due to changes in ambient temperature, as shown in Figure 3.
A slight gap 12 may occur at the boundary between the concrete and the concrete. However, when a small amount of water enters this gap 12, the seal layer 10 absorbs the intruding water and expands, closing and sealing the gap 12 as shown in FIG. Therefore, even if the surface of the concrete is covered with water, since the gap 12 is closed, water will not flow into the boundary between the joint cutting material 1 and the concrete.

In addition, in FIGS. 1 and 2, 6' is the exposed plate part 8.
A release paper that protects the top surface of the product from being scratched and is removed after installation.

The joint material 1 of this invention can also be used as a wall joint material, as shown in FIG. According to the embodiment shown in FIG. 5, the joint cutting material 1 has locking members 13 having a T-shaped cross section protruding from the upper and lower surfaces of the front frame 3 having a substantially U-shaped cross section, and A sealing layer 10 is provided between the base end of the stopper member 13 and the end of the front frame 3. When the concrete wall surface d gets wet, the seal layer 10 absorbs water and expands, closing the gap created at the boundary between the joint cutting material 1 and the concrete. Therefore, even if the wall surface d gets wet during rain, water will not flow in from the boundary between the concrete and the joint cutting material 1. In Fig. 5, 14 indicates a formwork for pouring concrete, and 15 indicates a concrete pouring surface.

As explained above, according to the present invention, a sealing layer that expands when it contains water is provided on the outer surface of the front frame, so when the surface of the concrete gets wet with water, the expanded sealing layer will not touch the concrete. Close and seal the gap with the joint cutting material. Therefore, even if the concrete surface is flooded, water will not flow into the concrete from the boundary between the concrete and the joint cutting material, preventing problems such as water leakage and water freezing in the gaps and destroying the concrete. This can be prevented.

In addition, since the sealing layer can be constructed using relatively inexpensive and easily available materials, the manufacturing cost is low. Since it can be used over a wide range of areas such as road surfaces, it has high practical value.

Although two types of configuration examples have been shown as joint cutting materials, the present invention can be used for any type of joint cutting materials.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a sectional view, FIG. 2 is a perspective view showing the state at the time of construction, and FIG. 3 is a partially cutaway sectional view of the top frame in a dry state. FIG. 4 is a partially cutaway sectional view of the front frame in a state where the seal layer is expanded, and FIG. 5 is a sectional view of another embodiment used as a wall joint material. 1... Joint cutting material, 3... Front frame, 10... Seal layer.

Claims (1)

[Scope of utility model registration request] A joint cutting material that divides the concrete surface by embedding a long front frame in the concrete pouring surface,
A joint cutting material for concrete characterized by having a sealing layer provided on the outer surface of the front frame that expands when it contains water.