JPS6363858A - Water and air permeable sheet like article for concrete panel and method for casting concrete using the same - Google Patents

Abstract

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

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a water-permeable material that is attached to the inside of a concrete panel for constructing concrete structures for architecture, civil engineering, etc.
This invention relates to an air-permeable sheet material and a method for placing concrete using the same.

(Prior Art) Concrete structures for architecture, civil engineering, etc. are constructed by framing wooden or metal concrete panels, pouring cement concrete into the frame, and curing and hardening the concrete. In recent years, buildings have become increasingly high-rise, and from the perspective of streamlining and promoting work, the ratio of water to cement has been increased to give fluidity to cement concrete and increase slump), and the above-mentioned improvements have been made by pumping up, pipe transportation, etc. Cement concrete was poured.

(Problems to be Solved by the Invention) However, although workability is improved by using cement concrete with a high water ratio as described above, the shrinkage of the concrete is large when excess moisture is dried after concrete is poured. As a result, cracks may occur, and the strength of the concrete cannot be demonstrated to its full potential, and many jumpers and joints are exposed. Furthermore, many voids are formed in the concrete structure, and water and air permeate through the voids, neutralizing the concrete and rusting the reinforcing steel, resulting in a significant decrease in the strength of the concrete structure. As is well known, the above-mentioned problems arose.

In particular, due to the recent modernization of construction, mortar finishing work on poured concrete surfaces has been omitted, and the acid concentration in the air tends to increase (especially noticeable in urban areas). If there are many voids in a concrete structure, problems such as salt damage and alkaline aggregate will become more and more important.

For this reason, a so-called water reducing agent has been developed and used, which can reduce the water ratio without reducing workability, that is, the slump of cement concrete. Among these water reducing agents, high-performance water reducing agents (plasticizers) can reduce water by nearly 20%, but the water reducing effect of such water reducing agents decreases over time (the water reducing effect is reached within 20 to 30 minutes after being added). As a result, considerable skill and careful attention were required when constructing high-rise buildings.

In addition, even if the water reducing agent mentioned above is used, the air bubbles contained in the cement concrete cannot be completely removed during or after pouring the concrete, resulting in small pinholes or holes in the concrete structure. a They remain as rough cavities or, in extreme cases, as junkers. If such pinholes or cavities exist in a concrete structure, they will cause a significant decrease in the strength of the concrete structure as described above.For this reason, the above concrete panels are made of double iron plates and holes are drilled in them to prevent air and moisture. Measures have been taken to absorb moisture and air from the cement concrete by placing a cloth over the surface of the perforated iron panels to absorb and release moisture and air from the cement concrete. Furthermore, a method has also been implemented in which a nonwoven fabric is impregnated with a water-absorbing gel and applied to the surface of a concrete panel to absorb excess water in the concrete.

However, among these methods, the method using a double iron plate requires a large-scale suction device, and the method of stretching a cloth over a perforated iron plate may cause the cloth to expand and block the holes, or cause mament paste to form. The drawback is that the air and water absorption and drainage functions are quickly diminished if the pores are blocked. also,
If a cloth made of densely woven vertical and horizontal twisted threads made of non-water-absorbing ultra-fine threads is used as the above-mentioned cloth, the releasability from concrete will be improved, but water at the interface will be rapidly removed, resulting in dry As a result, the concrete loses its fluidity, creating many voids, and the concrete surface is not finished beautifully.Furthermore, in order to make both functions more effective, it is necessary to provide as many holes as possible in the steel plate. but,
There was also a point that the processing cost required for drilling the holes was high. On the other hand, with the method of impregnating and carrying water-absorbing gel on non-woven fabric, etc., the cement absorbs water immediately after concrete is placed, so the cement does not dry out, and the non-woven fabric impregnated with water-absorbing gel sticks firmly to the concrete, so it hardens. Later peeling was extremely difficult, and like the above-mentioned iron plate covered with cloth, degassing was incomplete, and air bubbles were often left on the concrete surface.

The present invention has been developed in view of the above, and is capable of efficiently discharging moisture and air in uncured concrete without drying out, and when pouring cement concrete with a high water ratio and high slump. New water permeability and air permeability for concrete panels that do not cause a decrease in the strength of the concrete structure, and can provide a concrete body with a uniform color (property) on the concrete surface and internal layer after hardening. The object of the present invention is to provide a sheet-like material and a method for placing concrete using the same.

(Means for Solving the Problems) The structure of the present invention for achieving the above object will be explained in detail based on the accompanying drawings. 1 to 7 are partial vertical sectional views showing various aspects of the sheet-like product of the present invention, and FIG. 8 is a perspective view showing an example of an assembled state of a concrete panel used in the method of the present invention. That is, the first invention (specific invention) of the present invention provides a surface layer I that has good mold releasability from poured concrete and has many water passage/ventilation pores in the thickness direction, and a For concrete panels consisting of a base layer (1) for maintaining gaps, which has a large number of water passage/ventilation gaps in the thickness direction that communicate with the pores shown in Table 91, and which does not buckle or unbalance under the heavy pressure of poured concrete. The second invention relates to a water-permeable and air-permeable sheet material, and the second invention is a surface layer on one side of the concrete panel P that has good mold releasability from poured concrete and has a large number of water-permeable and ventilation pores in the thickness direction. I and this surface layer I
A water passage provided on the back side of the WI and communicating with the pores of the front WI.
Adding a sheet-like material S consisting of a base layer (1) for maintaining gaps that has a large number of ventilation voids in the thickness direction and that does not buckle or unbalance under the heavy pressure of the poured concrete, and concrete with this sheet-like material S inside. This concrete placing method comprises assembling a panel frame A and placing cement concrete inside the frame A.

The layer thickness of the base layer (2) here is suitably 0.1 to 10 rm (preferably 2 to 5 m), and the layer thickness of this base layer (2) is O',1
If it is less than ++m, the cement particles will fill up, resulting in insufficient water flow/ventilation capacity, and if it exceeds Low, there is a high risk of buckling or pressure deviation due to the heavy pressure of the concrete. In addition, when the sheet-like material of the present invention is used to pour concrete, excess moisture and air in the concrete are gradually dehydrated and degassed within 3 to 30 minutes after pouring. If the concrete is dehydrated and degassed for less than 3 minutes, a surface dryout phenomenon will occur, causing the concrete to lose its fluidity and tend to form a large number of voids, while if it is left in this manner for more than 30 minutes, the intended purpose will not be achieved.

The material used for the surface layer 1 must not be a material that is hydrophilic and easily adheres to cement, such as cotton or fiber.
Non-polar nylon, polyethylene, polyester, vinyl chloride, vinylidene chloride, ethylene vinyl acetate, various synthetic rubbers, etc. are desirable in terms of releasability and good appearance of the concrete surface after peeling.

Figure 1 shows a large number of pores 11...
・Drilling (hole diameter, 0.1-3I, interval, 11-5ai)
The above-mentioned sheet-like product is a plastic molded product 1 having a large number of support legs 12 formed on the back surface thereof. The molded product 1 is used by fixing the lower ends of the legs 12 to the concrete panel P, and in this state, the upper surface is the surface layer I, and the part partitioned by the upper surface and the concrete panel P is The base layer is
... correspond to the pores in the surface layer (2), and the air space partitioned by the panel P and the plastic molded product 1 corresponds to the voids in the base layer H, respectively.

FIG. 2 shows a thread (made by cutting a porous film or a plastic film cut into long pieces) attached to the back surface of the plastic molded body 1.
50 to 2000 denier) plain-woven Herashan cloth style sheet (hereinafter referred to as Herashan cloth for convenience)
2 are attached together, and the sheet 2 is used by being fixed to a concrete panel with the attached side facing up. In this case, the sheet 2 is used as the surface layer I, and the plastic molded product 1 itself is used as the base layer (2), and a large number of pores in the sheet 2 are partitioned into the pores of the surface layer I by the panel P and the plastic molded product 1. The air spaces that are filled correspond to the air gaps of the base layer (1).

In FIG. 3, a sheet 2 similar to that shown in FIG. 2 is integrally attached to the surface of a plastic molded article 3 formed into a corrugated shape using the same plastic material as described above. In this case, sheet 2 is also the surface layer! , the plastic molded product 3 itself is the base layer (2), the many small pores of the sheet 2 correspond to the pores of the surface layer I, and the voids formed by the peaks and valleys of the plastic molded product 3 correspond to the voids of the base layer H. do.

In FIG. 4, a thick mat 4 such as a needle punch carpet or felt is used as a base layer (2), and a sheet 2 similar to the above is attached as a surface layer (1) to the surface thereof.

In this case, the interfiber voids in the mat 4 correspond to the voids in the base layer (2), while the large number of small pores in the sheet 2 correspond to the pores in the surface layer (2), as described above.

Figure 5 shows a structure in which a base layer is an open foam 5 made of synthetic resin, synthetic rubber, or natural rubber such as urethane, polyethylene, styrene, and rubber, and a sheet 2 similar to the above is attached as a surface layer (2) to the surface of the open foam 5. be. In this case, the open cells in the foam 5 correspond to the voids in the base layer (2), while the same applies to the sheet 2 as described above.

In FIG. 6, a base layer I is made of pulp matsuro made by compressing a large number of pulp chips, and a sheet 2 similar to the above is integrally attached to the surface of this base layer I. As shown in FIG. In this case, the inter-chip voids in the pulp maturo correspond to the voids in the base layer H, while the sheet 2
Regarding this, it is the same as above.

In FIG. 7, the surface of a needle punch carpet 7 is partially fused, the fused surface is used as a surface layer I, and the layer below the fused surface is used as a base layer 2. In this case, the non-fused portions of the fused surface correspond to the pores of the surface layer I, and the voids between the fibers contained within the thickness of the needle punch carpet 7 correspond to the voids of the base layer H.

The above shows various embodiments of the sheet-like product of the present invention, but other materials such as rock wool punching, perforated asbestos plates, wood wool cement plates, etc. can also be used as the base layer H. In the case of wood wool cement boards, they can also be used as concrete panels because they have great strength.

The method for placing concrete according to the second invention is to fix the sheet-like material S to the surface of the concrete panel P using an adhesive or suitable fasteners, or to separately prepare the surface layer I and the base layer When fixing it to the surface of P, it is simultaneously stacked and integrated, and this panel P is framed into an appropriate shape to form a concrete panel frame A. High slump cement concrete is poured into the frame A, and further After curing, this frame A is removed to obtain a concrete body.

When fixing the sheet S to the panel P, the surface layer I
If the surface layer I is made larger than the base layer II, and the sides of this surface layer I are made to overlap at the joint between sheet materials, there will be virtually no gap at this joint, and the finished appearance of the concrete body surface will be improved. do. In addition, the sheet-like material S is connected to the panel P.
It is also effective to bend the water around the outer edge of the pipe and drain water and exhaust air from this part as well.

(Function) When the concrete panel P to which the sheet material S of the present invention having the above structure is attached is framed to form a frame A, and cement concrete with a high water ratio is poured into this, a large amount of The contained moisture and air pass through the many pores in the top and bottom layers and reach the voids in the base layer (2), where they are either stored or discharged to the outside of the panel along the inner surface of the panel. Therefore, the concrete body after curing and hardening has no cracks or rust on the reinforcing bars due to water drying, and is extremely strong as a whole without pinholes or cavities (compressive strength is 25 to 50% higher than before). ) becomes a structure.

In addition, the above-mentioned surplus water and air are gradually discharged within 3 to 30 minutes after pouring, so the surplus water and air that have naturally flowed from within the concrete body are naturally discharged, and the water-absorbing gel and Unlike the conventional method of rapidly absorbing water using a water-absorbing woven fabric, dry-out of cement does not occur at the interface, so the movement of water and air inside the concrete does not stop, and the surface of the concrete after peeling is extremely Beautifully finished.

Furthermore, since the surface layer I has good releasability from concrete, it can be easily peeled off from concrete without using a mold release agent or the like. In particular, in the case of woven or non-woven fabrics made of twisted threads, the cement paste wraps around the back side of the twisted threads, creating a high resistance when peeled off and making the skin of the peeled surface irregular, degrading the aesthetic appearance. When Vera Shan Cloth, a thin strip of plastic, is used as the surface layer ■, the cement paste does not get around to the back side, making it extremely easy to peel off, and the peeled surface has a regular and glossy appearance, giving it a good finish even as it is. It can be a face.

Furthermore, the color of the surface layer and the inner layer is the same cement color (dark gray), no chalking is observed, and the whole has uniform properties. This is because when the concrete hardens, excess moisture and air inside the concrete are discharged at a moderate rate than the sheet material S, and therefore alkali is not unevenly distributed on the surface (referred to as the eflo phenomenon).

(Example) Next, examples will be described.

(Example-1) Small holes with a hole diameter of 2 m were drilled at an interval of 0.8 mm and a thickness of 1.5 ~
1.Mold an 8-inch vinyl chloride sheet into the shape shown in Figure 1, and attach this molded product to one side of a 0.9m x 1.8m concrete panel, so that the molded products are on the inside of each other. A panel body A for concrete pouring as shown in Fig. 8 was framed with an interval of ].

Fluid cement concrete made by adding water to a mixture of cement: fine aggregate: coarse aggregate = 1:2:4 to form a slump 20a1 was placed on the panel body A while applying vibration.

After 7 days, panel body A was released from the mold. Release from the mold is extremely easy, and the surface has a glossy finish similar to that of plastic. Moreover, the surface color is the same cement color as the inner layer (
This can be understood to mean that no shift of alkaline content to the surface occurred due to the behavior of moisture or air during curing and curing. In addition, 2.4Q of water was collected on both sides of the excess water tray A-yu attached to the lower part of the panel body A.

This corresponds to a water reduction rate of 10% or more, and it is understood that water is being removed extremely efficiently from the concrete at the time of pouring. In addition, the concrete body that had been sufficiently cured and hardened in the panel body A had some pinholes in the positions corresponding to the small holes in the molded body, but it was extremely strong with almost no cracks or cavities. Ta. Incidentally, when the compressive strength was measured after 28 days of curing, it was 226 kg/J, which was a 29.1% increase in strength compared to the conventional method (175 kg/ai).

(Example-2) On the back side of the plastic molded product of Example 1, a thickness of 0.05
800 denier vinyl chloride sheet was attached, and the panel body A shown in FIG. 8 was framed with this berashan cloth as the concrete pouring side. When cement concrete similar to the above was poured into this panel body A, the water supplied to the tray A1 after one day was 2°8Q. Furthermore, the mold was released very easily, and the surface had a gloss similar to that of a plastic surface, and there were almost no pinholes. In this case, the compressive strength similar to Example 1 is 252 kg/CXl, which is 44%.
The strength increase rate was .

(Example-3) On a semi-rigid urethane continuous foam with a thickness of 5 m,
1m, 150o denier Heshan cloth was partially adhered with an adhesive, and the panel body A was framed with this Heshan cloth on the concrete pouring side in the same manner as described above. When cement concrete similar to the above was poured into this panel body A, water did not accumulate in the tray A1, but a comparable amount of water was absorbed into the foam. Moreover, the mold release was easy, and the mold release surface had the same gloss as Heshan cloth, and there were almost no pinholes. When the compressive strength was measured in the same manner as in Example 1, it was 256 kg/cJ, which corresponds to an increase of 46.2% compared to the conventional method. A similar Hesshan cloth was partially adhered with an adhesive, and the panel body A was framed with the Hesshan cloth placed on the concrete panel side in the same manner as described above. When cement concrete similar to the above was poured into this panel body A, substantially the same results as in Example 3 were obtained. In this case, the above compressive strength is 4
It increased by 5%.

(Experiment example) ■ A sheet made of porous rayon nonwoven fabric impregnated with water-absorbing gel, and ■ A sheet made of 1000-denier hesochan cloth stretched over 1000-denier urethane foam.
These sheets ■ and ■ are respectively pasted on the inner surfaces of opposing panels P and P of frame A shown in Fig. 8, and cement: fine aggregate: coarse aggregate: = 1:2 is placed inside this frame A. :4 (parts by weight) and cement concrete mixed with a water ratio of 65% was poured.

Progress observation〉 In the part marked with ■, it absorbs water in about 10 seconds and is 1 to 1.5 times thicker than the wall.
In the c++ area, the concrete dried out and lost fluidity.

In the part (■), the fluidity was not lost, and after 3 to 5 minutes, saucer A1
water began to accumulate. When vibrations were applied to the inside of the concrete, the flow of water increased rapidly. After about 40 minutes, the water stopped flowing and the collected water was completely clear.

When frame A was released from the mold after curing for 7 days, ■ was easily released from the mold together with panel P, but ■ was firmly adhered to the concrete and was not easy to release, and if you tried to forcefully remove it, it would not work. Some nonwoven fabric remained on the concrete surface.

<R inspection of the finished surface> Part (2): The surface was uneven and lacked luster, with traces of air bubbles being seen here and there, and the color was chalky gray.

Part (■): A glossy pattern similar to Hesochan cloth remained on the surface, and the surface and interior were the same black-gray color. Although some pinholes were observed, there were no large cavities.

In addition, the paint finish properties of the finished surfaces of both were investigated, and in the case of (■) a good appearance could not be obtained unless at least two coats were applied, but in the case of (2), one coat was sufficient.

The above comparison results are summarized in the table below.

However, x indicates adhesiveness due to finishing materials such as mortar.

It goes without saying that the present invention is not limited to the above embodiments, and that other changes can be made without departing from the scope of the present invention.

(Effects of the Invention) As shown in the above, the water-permeable and air-permeable sheet material for concrete panels of the present invention has extremely good mold releasability from poured concrete and has a surface layer with many water-permeable and ventilation pores. and a base layer for retaining gaps, which is provided on the back side of this surface layer and has a large number of water passage/ventilation voids in the thickness direction that communicate with the pores of the surface layer, and does not buckle or unbalance under the heavy pressure of the poured concrete. Therefore, when this is added to the inner surface of a concrete panel and cement concrete is poured, the moisture and air in the cement concrete will be discharged at an appropriate rate without drying out, making it possible to use cement concrete with a high water ratio. Even after demolding, the occurrence of cracks and voids, rusting of reinforcing bars, pinholes, etc. are significantly reduced, making it possible to construct an extremely robust concrete structure, and therefore workability is improved. It will be maintained in the same way as the simplest conventional construction method, and will also solve the problems of concrete neutralization, sea sand salt damage, alkaline aggregate, etc., which have become problems in recent years. In addition, it is extremely easy to release the mold from the concrete, and the appearance of the mold release surface is also very good.The color of the surface layer and internal layer is dark gray and the properties are uniform, which is completely unimaginable with conventional concrete structures. The result is a high-quality finish that would be impossible to achieve even with other products, and it changes that image.

[Brief explanation of the drawing]

1 to 7 are partial vertical cross-sectional views showing various aspects of the sheet-like product of the present invention, and FIG. 8 is a perspective view showing an example of an assembled state of a concrete panel used in the method of the present invention. (Explanation of symbols) I...surface layer, ■...base layer, A...concrete panel frame, P...concrete panel, S
...Sheet-like material. One or more applicants Central Engineering Co., Ltd. Agent Patent Attorney (6235) Hidehiko Matsuno Figure 1 Figure 2, Figure I3 Figure 4 Figure 5 and Figure 6 Figure 7 Procedure person n (voluntary) November 27, 1986

Claims (1)

[Claims] 1. Good mold releasability and water permeability for poured concrete.
It has a surface layer with a large number of ventilation pores, and a large number of water passage/ventilation voids in the thickness direction that are provided on the back side of this surface layer and communicate with the pores in the surface layer, so that it does not buckle or unbalance under the heavy pressure of poured concrete. A water-permeable and air-permeable sheet material for concrete panels, consisting of a base layer for maintaining gaps. 2. The sheet-like article according to claim 1, wherein the surface layer is made of a plastic plate. 3. The sheet-like article according to claim 1, wherein the surface layer is a plain-woven sheet made of threads obtained by cutting a plastic film into thin strips. 4. On one side of the concrete panel, there is a surface layer that has good mold releasability from the poured concrete and has many water passage/ventilation pores in the thickness direction, and on the back side of this surface layer, there is a A sheet-like material consisting of a base layer for maintaining gaps that has many communicating water passage/ventilation voids in the thickness direction and does not buckle or pressure bias under the heavy pressure of poured concrete is added, and this sheet-like material is placed inside. A method for placing concrete, in which a concrete panel frame is assembled, cement concrete is poured into the frame, and water and air are gradually dehydrated within 3 to 30 minutes after placement. 5. The casting method according to claim 4, wherein the surface layer is made of a plastic plate. 6. The casting method according to claim 4, wherein the surface layer is a plain-woven sheet made of threads obtained by cutting a plastic film into thin strips.