JPH0470467A - Water permeable formwork - Google Patents

Abstract

PURPOSE:To improve the workability by pasting a drain mat of synthetic resin sheet on a concrete cast surface side of a formwork base board, in which many air caps are arranged, and pasting together a permeable nonwoven fabric on an upper surface of the drain mat. CONSTITUTION:A drain mat 2, in which many air caps 2a are arranged, is pasted in zigzag shape on a concrete cast surface side of a formwork base board 1, formed of non-permeable synthetic resin, to uniformly receive a side pressure at the time of casting concrete. An underground wall is formed by casting concrete 4 facing a permeable nonwoven fabric 3 toward the concrete cast surface side. Surplus water is absorbed to flow downward. That is, the water is drained to flow down with a space part by the air cap 2a of the drain mat 2 serving as a water flow path. The permeable formwork is built in partly as its underground wall and left as not removed. In this way, the construction period can be shortened by improving the workability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a Hunkreet formwork material for underground walls, etc., and particularly to a formwork having a water permeability function.

[Prior Art] Conventionally, for example, formwork materials for concrete basement walls are composed of weir plates such as plywood or steel plates and shoring, and must be dismantled and removed after concrete is poured.

In addition, because concrete underground walls that have been poured have a slight permeability, groundwater may infiltrate and seep into the inner surface of the wall.As a waterproofing measure, for example,
As shown in the figure, concrete block walls are formed at appropriate intervals inside the concrete underground wall a, and this gap is used as a conduit C to allow the infiltrated water to flow down from the bottom of the underground wall to the bottom of the slab d. A method is adopted for draining water by providing a drainage hole e through which it passes.

[Problem to be solved by the invention] As mentioned above, in the process of placing concrete underground walls,
After assembling and pouring the formwork one by one, dismantling and removing the formwork is extremely troublesome and has poor work efficiency, and is one of the causes of impeding the shortening of the construction period, so there is a strong demand for improvement. There is.

In addition, if a concrete block wall is installed on the inside as a measure to drain incoming water, it takes a lot of time to stack the blocks, the structure becomes complicated, and construction costs increase. Due to the heavy wall structure, the indoor side becomes narrow and the effective space is reduced.

The present invention was made in order to solve the conventional problems as described above, and it eliminates the need to dismantle and remove formwork after pouring concrete for underground walls, etc., thereby improving workability and shortening the construction period. The object of the present invention is to provide a water-permeable formwork that can easily drain water that enters from the outside and secure a wide indoor space without the need for a water-permeable formwork.

[Means for Solving the Problems] As a means for technically solving the above-mentioned problems, the present invention provides a drainage mat attached to the concrete casting surface side of the formwork substrate, and a water-permeable material on the upper surface of the drainage mat. The gist is a structure in which nonwoven fabrics are bonded together.

[Function] The permeable formwork can be used as is as part of an underground wall after concrete is poured, so there is no need to dismantle it. and drain the water.

[Example] Hereinafter, as an example of the present invention, an example in which the present permeable formwork is used for an underground wall will be described in detail based on the accompanying drawings.

FIG. 1 shows an embodiment of the present invention, in which numeral 1 is a formwork substrate made of water-impermeable synthetic resin, such as hard urethane foam, and the formwork substrate 1 has drainage water on the concrete pouring side. Cloak 2 is attached. The drainage mat 2 is made of polyethylene or the like and has a thickness of about 0.2+iw, and there are many air caps 2a on the concrete pouring surface side.
are arranged side by side. As an example of this air cap 2a, as shown in Fig. 2, when the centers of three adjacent air caps are connected, it becomes an equilateral triangle with one side (L) of 20 cm, and the diameter (D) of each air cap 2a is +2+m is set so that the strength (H) is about 8■. The reason why the air caps 2a are provided in a staggered manner is to evenly receive lateral pressure during concrete pouring. The arrangement state and size of the air caps 2a, the thickness of the drainage mat, etc. are not limited to those described above, and can be appropriately set according to various conditions. Reference numeral 3 denotes a water-permeable nonwoven fabric, which is attached to the air cap 2a side of the drainage mat 2.

The permeable formwork according to the present invention is constructed as described above, and an underground wall can be formed by placing concrete 4 with the permeable nonwoven fabric 3 facing the concrete placing surface side. At this time, the water-permeable non-woven fabric 3 absorbs excess water from the concrete 4 and drains it downward. It can be drained by flowing down as a waterway. After the concrete 4 is placed, the permeable formwork is left behind and incorporated as part of the underground wall, so there is no need to dismantle and remove it.

Therefore, handling of the permeable formwork on site is extremely easy, work efficiency is significantly improved, and construction period can be shortened.

Even if groundwater etc. infiltrates from the outside, that is, from the poured concrete 4 side after the underground wall is formed, the water will be absorbed into the concrete 4.
At the same time, it is absorbed by the permeable nonwoven fabric 3 and flows down, or flows down through the space of the drainage mat 2 as a channel to reach the lower end of the underground wall, and as in the conventional case, it flows from the drainage hole to the lower part of the slab. is drained. The space in the drainage mat 2 functions not only as a water passageway but also as a ventilation passageway, so it is useful for preventing dew condensation on the underground wall. Furthermore, the air cap of the drainage mat can withstand lateral pressure during concrete pouring and can maintain the space.

The form substrate does not corrode, has excellent durability, and has good heat insulation properties, so it is suitable as an interior base material, and it is also convenient because it is possible to directly attach finished interior materials to its surface.

[Effects of the Invention] As explained above, according to the present invention, a water-permeable formwork is formed by pasting a drainage mat on the concrete pouring surface side of the formwork substrate and pasting a water-permeable nonwoven fabric thereon. Therefore, it can be integrated as part of the underground wall after concrete pouring, eliminating the need for dismantling and removing it, significantly improving work efficiency on site and shortening the construction period. I can do it. In addition, groundwater that has entered from the outside of the basement wall can be drained by flowing down through the permeable non-woven fabric and drainage mat, eliminating the need to form an inner wall of concrete blocks as in the past, thereby increasing the effective indoor space. Because it is easy to secure and has a simple structure, it has excellent effects such as reducing construction costs.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a portion of an embodiment of the present invention, FIG. 2 is a rear view of a portion of a drainage mat, and FIG. 3 is an explanatory diagram of a conventional example. 1... Formwork board 2... Drainage mat 2a.
...Air cap 3...Water permeable nonwoven fabric 4...Concrete

Claims (2)

[Claims] (1) A water-permeable formwork characterized in that a drainage mat is attached to the concrete pouring side of the formwork substrate, and a water-permeable nonwoven fabric is attached to the upper surface of this drainage mat. (2) The water-permeable formwork according to claim (1), wherein the drainage mat is formed of a synthetic resin sheet, and a number of air caps are arranged in parallel on the concrete pouring surface side.