JP7518650B2 - Dry backfill construction method for drainage systems and drainage pipes - Google Patents

Description

The present invention relates to a drainage system and a dry backfill construction method for drainage pipes.

When a drainage stack passes through a fire compartment of a building, it needs to be fire-resistant to prevent the spread of fire. For this reason, cast iron pipes and fire-resistant double-layer pipes have traditionally been used as drainage stacks. In addition, plastic pipes are sometimes used as drainage stacks because they are light and rust-resistant.
The drainage stand pipe penetrates the slab. In the past, the hole in the slab was generally filled with mortar, which can suppress the spread of flames and smoke in the event of a fire on the floor below (see, for example, Patent Document 1).

JP 2009-024411 A

However, when backfilling with mortar at a construction site, it is necessary to mix cement, aggregate, and water, which makes it difficult to work with. In addition, mortar mixed with water gradually hardens, making it difficult to handle, and there was a demand for a dry construction method in which the through-holes in the slab are backfilled with rock wool or similar. However, simply backfilling with rock wool poses the problem of smoke from inside the furnace passing through to the non-heated side during fire resistance tests. Also, due to issues with the Building Standards Act, drainage systems that use rock wool as a backfilling material are limited to steel pipes such as cast iron pipes, narrowing the range of use.

The present invention was made in consideration of these problems, and aims to provide a drainage system and a dry backfill construction method for drainage pipes that use rock wool as a backfilling material and are easy to install and safe.

In order to solve the above problems, the present invention proposes the following means.
A drainage system according to one embodiment of the present invention is characterized in that it comprises a resin pipe containing thermally expandable graphite placed in a slab penetration hole formed in a slab, rock wool filled between the outer surface of the resin pipe and the inner surface of the slab penetration hole, a backing plate that supports the rock wool from below the slab, and a sealing plate that is fitted into the resin pipe and seals the slab penetration hole from above.

With the above drainage system, in the event of a fire, the resin pipe containing thermally expandable graphite that is installed in the slab penetration hole expands, and the rock wool in the slab and the thermally expanded resin pipe become entangled, forming a large residue. This residue prevents hot air from escaping to upper floors. In addition, the rock wool and residue prevent the temperature of the top surface of the slab from rising significantly, preventing the spread of fire.

In the above drainage system, the sealing plate may have a flange that protrudes into or outside the slab penetration hole and is fixed by caulking.

With the above drainage system, the slab penetration hole filled with rock wool and the plastic pipe can be fixed with a sealing plate. It also prevents smoke from escaping through the rock wool in the event of a fire.

In addition, a method for dry backfilling of drainage pipes according to one aspect of the present invention is characterized by including the steps of placing the plastic pipe in the slab penetration hole, installing the backing plate at the bottom of the slab penetration hole, filling the slab penetration hole with rock wool from the floor above the slab penetration hole, and fitting the sealing plate into the plastic pipe from the floor above the slab penetration hole.

The above-mentioned dry backfill construction method for drainage pipes ensures safety, just like the drainage system described above.

The drainage system and drainage pipe dry backfill construction method of the present invention provide excellent workability and ensure safety.

FIG. 13 is a front view showing the drainage system when the flange of the sealing plate protrudes downward. FIG. 2 is a perspective view of the sealing plate shown in FIG. 1 . FIG. 2 is a top view of the sealing plate shown in FIG. 1 with the upper and lower sides sealed with caulking or tape. FIG. 1 is a front view of the drainage system when the flange of the sealing plate is protruding downward, according to an embodiment of the present invention. FIG. 13 is a front view showing the drainage system when the flange of the sealing plate protrudes upward. FIG. 6 is a perspective view of the sealing plate shown in FIG. 5 . FIG. 1 is a front view of the drainage system when the flange of the sealing plate is protruding upward, according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a drainage system and a dry backfilling construction method for a drainage pipe will be described.
In describing the present invention, the drainage system will first be described.

(Drainage system)
As shown in FIG. 1 , the drainage system 11 includes a resin pipe 1 , a backing plate 4 , and a sealing plate 5 .

(Resin pipe)
The plastic pipe 1 penetrates the slab penetration hole 3 of the slab 2 as a drainage standpipe. The nominal diameter (approximate inner diameter) of the plastic pipe 1 is 40A to 200A as specified by the symbol VP of JIS K6741. The opening diameter of the slab penetration hole 3 is preferably 3 sizes larger than the nominal diameter of the plastic pipe 1, and more preferably 2 sizes larger. Specifically, the nominal diameter of the plastic pipe 1 increases in the order of 40A (40 mm), 50A (51 mm), 65A (67 mm), 75A (77 mm), 100A (100 mm), 125A (125 mm), 150A (146 mm), and 200A (194 mm). Therefore, when the size of the plastic pipe 1 is 75A, the opening diameter of the slab penetration hole 3 is preferably 150A or less, and more preferably 125A or less.
In addition, rock wool 6 is densely packed between the outer surface of the resin pipe 1 and the inner surface of the slab through-hole 3.
A polyvinyl chloride pipe containing thermally expandable graphite is used as the resin pipe 1. The amount of thermally expandable graphite is 1 to 26 parts by mass, preferably 5 to 20 parts by mass, and more preferably 8 to 18 parts by mass, per 100 parts by mass of polyvinyl chloride. This allows the resin pipe 1 to thermally expand quickly in the event of a fire, and to become entangled with the rock wool 6 to form a residue.
The inside of the pipe may have a single-layer structure in which the thermally expandable graphite is present throughout the entirety of the polyvinyl chloride pipe, a two-layer structure in which the thermally expandable graphite is present in the inner and outer layers, or a three-layer structure in which the thermally expandable graphite is present only in the middle layer, but it is preferable that the outermost layer is a polyvinyl chloride resin layer that does not contain thermally expandable graphite. This allows the molten polyvinyl chloride resin to entangle the rock wool 6 when the resin pipe 1 expands, making it easier to form a residue.
The thermally expandable graphite used has a thermal expansion start temperature of 220° C. to 280° C., and preferably 240° C. to 270° C. This makes it easy to manufacture the resin pipe 1 even if it contains a large amount of thermally expandable graphite, and the resin pipe 1 thermally expands quickly in the event of a fire.
In addition, by using resin for the drainage standpipe, it is lighter and easier to install than steel pipes such as cast iron pipes, and it does not rust.

(Backing plate)
The backing plate 4 is installed at the bottom of the slab through-hole 3 so as to support the rock wool 6. The backing plate 4 is a plate with an opening formed in the center in a plan view. The resin pipe 1 is fitted in the opening of the backing plate 4. The outer shape of the backing plate 4 is larger than the outer shape of the slab through-hole 3.
A metal backing plate such as A-Pad (manufactured by Akagi Corporation) is used as the backing plate 4. This prevents the backing plate 4 from burning even in the event of a fire.

(Rock wool)
The rock wool 6 is specified in JIS A 9504. In addition, the rock wool 6 may be replaced with a rock wool heat-insulating tube or a moisture-retaining band.

(Sealing plate)
The sealing plate 5 is installed on the upper part of the slab through-hole 3 so as to cover the rock wool 6. The sealing plate 5 is fixed using caulking, tape, or the like.
The sealing plate 5 may be made of metal, resin, or ceramic, but is preferably made of resin in consideration of cost and ease of installation. As for the resin, it is particularly preferable to use polyvinyl chloride resin in terms of fire resistance.
The sealing plate 5 is formed by dividing a plate having a through hole in the center into a plurality of pieces. In the illustrated example, the sealing plate 5 is formed by dividing the plate into two pieces in the horizontal direction.

2 and 6, the sealing plate 5 is provided with a flange 7. The flange 7 protrudes from the sealing plate 5 in the plate thickness direction of the sealing plate 5. The flange 7 protrudes from the periphery of the slab through hole 3 in the sealing plate 5. The flange 7 has a shape in which a portion along the circumferential direction of a cylinder is removed.
When the sealing plate 5 of Fig. 2 is used, the drainage system 11 will be as shown in Fig. 1 and Fig. 4. When the sealing plate 5 of Fig. 6 is used, the drainage system 11 will be as shown in Fig. 5 and Fig. 7. That is, the flange 7 may protrude into the slab penetration hole 3 as shown in Fig. 1 and Fig. 4, or may protrude out of the slab penetration hole 3 as shown in Fig. 5 and Fig. 7. The sealing plates 5 of Fig. 2 and Fig. 6 have the same shape, but differ in whether the flange 7 protrudes into the slab penetration hole 3 or out of it.

The width of the flange 7 (the length in the axial direction of the resin pipe 1) is preferably 2 mm or more, and more preferably 10 mm or more in order to ensure reliable caulking or taping.
The caulking or taping is performed so as to densely fill the gaps between the resin pipe 1, the slab 2, and the sealing plate 5, as shown as the fixing portion 10 in Figs.
As the caulking material, it is preferable to use silicone caulking or modified silicone caulking.
It is preferable to use an aluminum tape as the tape. The sealing plate 5 may be fixed by only caulking, by only tape, or by a combination of caulking and tape.

(Construction method)
Next, a construction method for the drainage system 11 configured as described above will be described.
First, the plastic pipe 1 is passed through the slab penetration hole 3. Then, a backing plate 4 is provided on the bottom of the slab 2. Rock wool 6 is embedded from the top of the slab penetration hole 3, and a sealing plate 5 is further fitted from above to cover the rock wool 6. Then, the plastic pipe 1, slab 2, and sealing plate 5 are fixed in place by caulking or taping.

(Function of drainage system)
Next, a case where the drainage system 11 configured as described above is used will be described.
As mentioned above, since the resin pipe 1 is a polyvinyl chloride pipe containing thermally expandable graphite, the polyvinyl chloride pipe expands in the event of a fire. At this time, the rock wool 6 in the slab penetration hole 3 and the thermally expanded polyvinyl chloride become entangled with each other, forming a residue. The volume of this residue makes it possible to prevent hot air from leaking to upper floors, even if porous fibers such as rock wool 6 are used as a backfill material.
At this time, the backing plate 4 can prevent the rock wool 6 and residue from leaking downward from the slab 2.
In addition, by using the sealing plate 5, it is possible to prevent smoke from inside the furnace from escaping upwards to the slab 2.
In addition, the rock wool 6 and the residue prevent the temperature of the top surface of the slab 2 from rising significantly, and the spread of flames does not occur.

The drainage system 11 configured as described above is also highly safe, even when rock wool is used as the backfill material. As a result, it can obtain certification from the Minister of Land, Infrastructure, Transport and Tourism and a performance evaluation from the Fire Protection Equipment Safety Center. In addition, because the above-mentioned discharge system uses a plastic pipe as the drainage standpipe, it is possible to expand the locations where the drainage system can be used.

Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. The embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. Examples of the embodiments and their variations include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the scope of equivalents.

Reference Signs List 1: Resin pipe 2: Slab 3: Slab through hole 4: Backing plate 5: Sealing plate 6: Rock wool 7: Flange 10: Fixing part 11: Drainage system

Claims (2)

a resin pipe containing thermally expandable graphite arranged in a slab through-hole formed in the slab;
Rock wool filled between the outer surface of the resin pipe and the inner surface of the slab through hole;
A backing plate that supports the rock wool from below the slab;
a sealing plate that is fitted into the resin pipe and seals the slab through hole from above ;
The sealing plate is
A flange protruding into or out of the slab through hole,
It is fixed by caulking,
A drainage system, characterized in that the caulking is provided between the flange and the plastic pipe and between the sealing plate and the upper surface of the slab. A method for constructing a drainage system according to claim 1 ,
placing the resin pipe in the slab penetration hole;
Installing the backing plate at the bottom of the slab penetration hole;
A step of filling the slab penetration hole with the rock wool from an upper floor of the slab penetration hole;
A dry backfill construction method for a drainage pipe, comprising the step of fitting the sealing plate into the resin pipe from the floor above the slab penetration hole.

Images