JPH02204573A - Form and method for placing concrete - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a formwork used for concrete pouring and a concrete pouring method.

(Prior technology) When pouring concrete, a formwork with a porous material such as non-woven fabric or synthetic resin net attached to the formwork plate is used to release air bubbles in the concrete and improve drainage of excess water. This method is known from, for example, Japanese Patent Laid-Open No. 60-43528 and Japanese Patent Laid-Open No. 61-137923.

(The problem to be solved by the invention) When these non-woven fabrics or synthetic resin nets are attached to a form board and used, simply attaching the non-woven fabric will result in poor attachment strength and may cause clogging. However, those with synthetic resin nets have large pores and are difficult to obtain a filtering effect.

In addition to these, in the former method disclosed in JP-A No. 60-43528, it is recommended to use a formwork board with many through holes because the outflow path for air bubbles and excess water becomes long. , the latter proposed in JP-A No. 61-137923, the present inventors have found that air bubbles in concrete are quickly removed and excess water is also filtered and discharged. It is a formwork that can be finished with a beautiful surface with almost no drainage holes or bubble holes on the finished surface, and it has been used traditionally as a formwork plate without having many through holes. We conducted research and experimented with the aim of being able to sufficiently remove air bubbles and filter and drain excess water even when using non-porous formwork plates, and furthermore, to enable easy concrete pouring at work sites. layered.

(Means for Solving the Problems) In order to achieve the above-mentioned object, this invention has a diameter of 0.05 m.
A filtration membrane in which a plastic film with micropores of m to 0.2 mm evenly distributed at intervals of 0.5 to 1.5 mm is laminated to the surface of a dense layer of nonwoven fabric consisting of two layers, coarse and dense. , the coarse layer of the non-woven fabric is fixed to a formwork board to form a concrete pouring form, and the diameter is 0.05 mm to 0.05 mm.
A filtration membrane in which a plastic film with 0.2 mm micropores evenly distributed at intervals of 0.5 mm to 1.5 mm is laminated to the surface of a dense layer of nonwoven fabric consisting of two layers, a coarse and a dense layer, is installed at the work site. By using a concrete pouring method in which concrete is poured while forming a formwork by fixing it to a formwork plate, the object can be well achieved, and the present invention has been achieved.

(Function) According to the formwork according to the present invention, air bubbles and excess moisture in the poured concrete pass through the fine pores of the plastic film that is in direct contact with the concrete, and then pass through the dense layer of nonwoven fabric that follows. Excess water is discharged from the two layers of the non-woven fabric, the dense fake layer and the original layer, and air bubbles are mainly released to the outside in the coarse layer of the non-woven fabric. Furthermore, when using the casting method of the present invention, the filtration membrane and the formwork plate are not fixed together in advance, but are formed and transported separately.
It has become possible to adopt a construction method in which concrete is poured while the filtration membrane is attached to the formwork plate at the work site to form the formwork.

(Example) An example of the implementation of this invention will be explained below with reference to the attached drawings. 1 is a form plate, which is a tree root or a steel plate used for concrete pouring, and has a predetermined shape. It is made in size and thickness. 2 is this formwork 12i
It is a filtration membrane fixed to i1, and this filtration 11M2 is made of a plastic film 3 and a nonwoven fabric 4 pasted together. This plastic film 3 has micropores 5 perforated, and the diameter of the micropores 5 is 0.05 mm to
It is within the range of 0.2 mm, and the interval between the micro holes 5 is 0.5 m.
The holes are uniformly distributed within a range of m=1.5 mm. Various means can be used to form the micropores 5 in the plastic film 3, but the most preferred method is laser processing. In addition, the nonwoven fabric 4 is composed of two layers, a coarse layer 4A and a dense layer 4B, and in order to have a two-layer structure of both layers 4A and 4B, the coarse layer 4A and the dense layer 4B are required. It is optional, such as thermal pasting or pasting with adhesive. In order to bond the plastic film 3 to the nonwoven fabric 4, the dense layer 4B of the nonwoven fabric 4 and the plastic film 3 must be bonded together.

In this way, the plastic film 3 and the nonwoven fabric 4 are laminated together in the dense layer 4B to form the filtration membrane 2. The formwork 6 is obtained by fixing this filtration membrane 2 to the formwork plate 1, but as described above, the basic layer 4A of the nonwoven fabric 4 of the filtration 1lU2 is fixed to the formwork plate l. . Filter it on the form board l!
In order to fix the filtration MM 2, it is normal that the filtration MM 2 is fixed to the size of the formwork plate 1, but as shown in FIG. In some cases, a filtration membrane 2 having a length longer than that is fixedly attached and used. At this time, the filtration membrane 2 is superimposed on the formwork plate 1 so as to protrude from the upper and lower side edges 7 of the formwork 1'1iil, and the upper and lower ends of the protruding filtration membrane 12 are folded into the periphery of the formwork plate. , the molds 6 are stacked in multiple stages.

The plastic films used in this invention, for example, polypropylene films, which harden easily in the winter, and nylon films, which are sensitive to alkalis, are not very preferable, but the type of other films does not matter; for example, Polyethylene film and the like can be said to be an example of a preferable film. Further, the thickness of the film may be as thin as possible so long as it does not break during concrete pouring, and for example, in the case of the polyethylene film, it is preferably 50 μm or more. Further, the film may be a single-layer film or a multi-layer film, but a multi-layer film is preferred since the film must be laminated with a nonwoven fabric.

The size of the micropores 5 formed in the film 3 is selected within the range of 0.05 mm to 0.2 mm in diameter, which is necessary to effectively prevent cement particles from flowing out and not to damage the nonwoven fabric. In order to satisfy both of these requirements, the diameter of the film micropores is determined by the diameter of the cement particles, and the diameter of the film micropores is determined by the diameter of the cement particles.
．． It will be 2mm. It is preferable to use laser machining to obtain the micro holes 5, but this is due to the uniformity of the diameter and
This is because the uniformity of the intervals can be obtained most accurately and the defective rate can be lowered.

Alternatively, a film in which micropores have been perforated in advance and a nonwoven fabric may be laminated together, but this cannot be said to be preferable because the micropores may be closed during lamination. It is preferable to perforate the film, and the aperture ratio per unit area is determined by the interval between the micropores,
Effective opening ratio can be selected by cement water ratio and concrete placement height.

In the nonwoven fabric used in this invention, a dense layer refers to a porosity in the range of 30% to 50%, and a coarse layer refers to a porosity in the range of 160 to 90%. In this case, the form board may be a non-perforated board made of wood, steel, etc., but a perforated board may also be used.

(Effects of the invention) When concrete is poured using the formwork according to the present invention, there are almost no bubble holes or drainage holes, which conventionally occur in many finished surfaces, and the concrete is beautiful and easy to pour even without using concrete finishing materials. The surface becomes smooth and beautiful enough to use, and the amount of finishing materials used is significantly reduced.

In addition, since the plastic film is in contact with the poured concrete, this plastic film plays the role of a release agent, allowing it to be removed as in the case of conventional formwork with only plates or non-woven fabric. I no longer need drugs.

Furthermore, since excess water in the concrete is smoothly drained, the moisture contained on the concrete surface is only the moisture necessary for hardening, and the initial strength is increased by lowering the water-cement ratio, making it possible to remove the formwork at an early stage. As a result, the implementation period can be shortened, and the curing period can also be significantly shortened.

First of all, the drainage rate of excess water is determined by the diameter and spacing of the micropores on the film surface, and at the same time, only the water passes through without passing through the concrete particles, and the water transfers to the nonwoven fabric layer. Even a small amount of concrete particles mixed in the mold will be captured by the dense layer of non-woven fabric, and the moisture discharged by the coarse layer of non-woven fabric will flow out of the formwork. Along with this moisture, air bubbles in the concrete will also be discharged out of the formwork through the same route.

In addition to these, the abrasion resistance of the concrete pouring surface is improved and the occurrence of cracks due to a decrease in the amount of curing shrinkage is prevented.

Furthermore, in the winter, the filtration membrane acts as a heat insulating material and has a heat retaining effect, and in the summer, the filtration membrane acts as a heat insulating material and a heat insulating material, significantly improving the curing effect. When the filtration membrane is created using the method of the present invention, it can be packaged in a roll and easily transported to the work site, and then fixed to any form board to form a form on site. Since the concrete can be placed while the concrete is being placed, it has made a significant contribution to simplifying the construction method and reducing costs.

[Brief explanation of the drawing]

The accompanying drawings are for explaining the present invention, and FIG. 1 is a longitudinal sectional side view showing an example of the implementation of the present invention. FIG. 2 is a side view schematically illustrating a state in which the formworks, each of which has an III film pasted thereon which is longer than the length of the upper and lower sides thereof, are stacked and used. l・Form plate 2: Filtration membrane 3. plastic film
4; Nonwoven fabric 4A: Coarse layer of nonwoven fabric 4B = Dense layer of nonwoven fabric 5. Micro holes 6: Formwork 7: Upper and lower ends of formwork plate Patent applicant Nippon Matai Co., Ltd. and 1 other name Engraving of drawings (no changes in content) 6'! Crushing procedure manual (method) % formula % Name of the invention Relationship between concrete pouring formwork and the case of a person amending the concrete pouring method

Claims (4)

[Claims] (1) Micropores with a diameter of 0.05 mm to 0.2 mm are 0.
．． A filtration membrane is made by laminating a plastic film uniformly distributed at intervals of 5 mm to 1.5 mm on the surface of a dense layer of non-woven fabric consisting of two layers, a coarse layer and a dense layer. Formwork for concrete pouring fixed to a board (2) The formwork for concrete pouring according to claim 1, wherein the formwork plate is non-perforated. (3) The formwork for concrete casting according to claim 1, wherein the filtration membrane is fixed to protrude from both the upper and lower ends of the formwork board. (4) Micropores with a diameter of 0.05 mm to 0.2 mm are 0.
．． A filtration membrane, which is made by laminating plastic films uniformly distributed at intervals of 5 mm to 1.5 mm on the surface of a dense layer of nonwoven fabric consisting of two layers, coarse and dense, is fixed to a form board at the work site. Concrete pouring method in which concrete is poured while forming formwork