JPS581078B2 - Curing method for cementitious molded bodies - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a curing method for heating and curing a cementitious material and a curing mold used therein.

Conventionally, cementitious materials take a long time to harden, so they have been heated to accelerate the hardening process, but generally the mold is carried into a heated room for curing and then hardened. It was being done.

However, this always requires a large room for curing, it takes a long time to raise the temperature at the beginning of use, and it is difficult to control the temperature while monitoring the curing status. there were.

In view of this, the present inventor has arrived at the present invention as a result of various studies on methods for easily curing and hardening cementitious molded bodies while preventing such drawbacks.

The present invention consists of a cementitious molded body and a filling layer placed on one side of the cementitious molded body and solidified by reduced pressure. A method for curing a molded body, wherein a mold for curing a cementitious molded body has at least one open surface and a filling adjustment means, and has a filter member for reducing the pressure of the filler and a means for heating the filler on its inner wall and/or inside. It is.

A feature of the present invention is that since the temperature can be controlled for each mold, curing can be performed while determining the curing state, so that the quality of the molded cementitious mold can be made uniform.

Especially in the case of continuous production, the injection time of cementitious material, that is, the curing state, differs depending on the mold, but since the temperature can be controlled for each mold, the optimal curing conditions can be set for each mold. be able to.

Similarly, even when cementitious molded products of various sizes, thicknesses, and raw materials are manufactured at the same time, the temperature can be controlled for each molded body, so optimal curing conditions can be set.

Another feature is that since the filler is used after being solidified by reducing the pressure, it is possible to mold various cementitious molded products with the same mold. By releasing the filling material, the cementitious molded product can be easily demolded by introducing pressurized air into the filling material.

Furthermore, by using a mold body for molding and a mold body for curing,
The cementitious material is hardened in the mold to the extent that it is no longer succulent.

Next, a curing mold having a heating means is placed, a filler is filled, the filler is solidified under reduced pressure to form a curing mold, the mold is detached, and the curing mold is Hold the cementum molded body only with the body.

Then, the cementitious molded body is cured and hardened by heating with a heating means arranged inside the molding body.

By doing so, the molding efficiency of the molding body can be increased, and productivity can be improved.

Cementitious materials for producing the cementitious molded product of the present invention include Boltland cement-slag cement, alumina cement, Roman cement, natural cement, hydraulic lime, magnesia cement, lime, gypsum, calcium silicate, etc. Slurry materials containing inorganic substances that harden in the presence of water, such as mixtures thereof, and the slurry materials together with sand, stones, rocks, other aggregates and/or asbestos, glass fibers, especially chopped strands, glass wool. , fibrous reinforcing materials such as steel fibers, carbon fibers, synthetic fibers, and/or synthetic resin polymers, foaming agents, rubber latex,
Mixtures of other additives can be used, and these slurries are injected into the mold by casting or spraying and allowed to harden.

As the filler of the present invention, granular, powder, pellet, flake, or other filler materials that have air permeability when filled can be used, and specifically, sand, metal, glass, or synthetic resin particles, or powder. Alternatively, there are crushed or hollow objects, wood flour, wood wool, shirasu, shirasu balloons, artificial lightweight aggregate particles, etc., and more than one of these may be mixed or used in layers, and the particle size of the layer closer to the surface is decreased. It is possible to make the filler finer, and by mixing magnetic particles, not only a reduced pressure but also a magnetic field can be applied to solidify the filler more firmly, as long as it is stabilized by the heating temperature.

Alternatively, a back mold may be provided on the back of the filling material through a filter member that has air permeability but does not allow the filling material to pass through, or an exhaust pipe equipped with a filter may be provided in the filling material, or the filter may be simply inserted from the back or side. By evacuating through the mold, the filling material inside the mold is brought into a reduced pressure state.

Furthermore, as another application, it is also possible to reduce the weight of the filler layer by incorporating a member such as a hollow body or a box body into the filler.

Next, the present invention will be explained based on examples.

FIG. 1 shows an embodiment of the curing mold of the present invention, which is hollow inside and has a large number of filter members 1 inside it, and a thousand heating stages 2 inside the mold. The frame body 3 shown in FIG.

This filter member is provided at 10 locations in the figure, but it is sufficient to provide a desired number of one or more locations, and it is not only a flat filter but also a tubular filter that extends across the frame. Also good.

As this heating means, known heating means such as an electric heater, a tubular body through which hot air, steam, or hot water flows can be used.

Also, although five heating means are shown in Figure 1,
The number, shape, etc. may be adjusted so that the filling material filled inside is heated uniformly or with desired non-uniformity.

Further, the frame is usually made of metal, but depending on the heating temperature, plastic, FRP, etc. can also be used, or a concrete tubular body with a lining or other airtight materials can be used.

FIG. 2 is a sectional view taken along the line AA of the frame shown in FIG. 1, showing a frame 3 having a cavity 4 therein, a filter member 1, and a heating means 2. As shown in FIG.

In addition, although the frame shown in Figures 1 and 2 is shown with its upper and lower surfaces completely open, it is necessary that the surface on which the molded body is placed is at least open; Material adjustment means, that is, a filling port for the filler and a mechanism that prevents voids from forming in the filler or deformation of the molded product when the pressure is reduced after filling the filler, such as a film or rubber that can be easily deformed. By providing a part to which something like this is pasted, or by providing a mechanism for immediately replenishing the filler material from the outside into the created void, there is no need to provide another open surface to be used as a filler adjustment means. It can also be made into a box-shaped body.

However, from the viewpoint of workability, it is preferable to provide two open surfaces: one for placing the molded product and another open surface for filling with a filler and providing a plastic film.

Next, a preferred example of implementing the method of the present invention will be described.

Note that the shielding layer used below is as described below.

As the shielding layer of the present invention, materials that form a non-air permeable or air permeable film-like material can be used, and specifically, plastic films, metal films, fine cloth, plastic thin plates, and materials mixed with a binder can be used. Alternatively, there are granular, powdery, flaky materials, thin rubber plates, paper, etc. that are not mixed.

If you want to create a smooth surface or a special patterned surface, you can use a plastic film or a film stamped with rubber, etc. You can also use this plastic film as a decorative film by leaving it on the surface of the molded object and using a slightly removed plastic film. It is also possible to obtain a covered cement panel, and by leaving the plastic film behind during demolding and peeling off the cut plastic film during use or construction, it is possible to transport or work without damaging the smooth surface or its patterned surface. There is also an advantage.

As another application, by using decorative colored sand as a shielding layer, injecting a cementitious material on top of this, and removing it from the mold after hardening, a molded object whose surface is colored with sand can be obtained. It is also possible to easily attach paper or other surface layer to the surface of the molded product and remove it from the mold.

However, if the shielding layer is not left as a surface layer during use, it is preferable to use a plastic film in terms of workability and moldability.

The breathable membrane material may also contain granules such as the colored sand described above, a sticky binder, or asbestos paper, glass cloth, other cloth or paper-like material, or porous material. When molding asbestos slate, glass fiber reinforced cement, etc. using a dehydration method, the cementitious material introduced while maintaining the filler such as sand under reduced pressure It is more effective because the moisture contained therein can be sucked into the sand through the air-permeable pores to promote hardening of the cementitious material.

However, in this case, air flows into the filling material in the mold through the breathable membrane material that is the shielding layer, so the capacity of the exhaust system needs to be sufficiently large. It is preferable to maintain a uniform reduced pressure state.

Figure 3 shows a shielding layer 5 such as a plastic film molded into a desired shape, and a filler 6 such as sand or other granules.
, a cementitious material 10 is introduced into a molding body consisting of a non-breathable membrane material 7 and an outer frame 9 having a filter member 8, in which the filling material is held under reduced pressure and solidified. After that, a frame body 3 equipped with a filter member 1 and a heating means 2 is placed through a sealing member 11 such as rubber, and a filler 12 that is the same as or different from the filler 6 is injected. ing.

After injecting the filler 12, a non-breathable membrane material such as a plastic film is placed on the open side 13 of the frame 3, which is not the side of the molded body, and the pressure inside the frame is reduced to solidify the filler 12. After the cementitious material has hardened to the extent that it does not flow at least, the reduced pressure of the molding body is released, and if necessary, pressurized air is sent to separate the filler material 6 and harden as shown in FIG. The cementitious material 10 is placed only on the mold, and heated to a desired temperature by the heating means 2 to harden the molded material made of the cementitious material.

It is also possible to provide a second shielding layer on the cementitious material 10 before injecting the filler material 12 and then inject the filler material.

The second shielding layer may be made of a film-like material such as a plastic film if it provides smoothness to the surface of the cementitious material like the shielding layer 5, or it may be made of a cloth-like material that is integrated with the cementitious material. You can also do it.

In addition, when hardening is to be accelerated, such as when using a cementitious material with a high water content, it is preferable to use a breathable film-like material, and when a smooth surface is not desired, it is preferable to use a film that adheres closely to the cementitious material. It is preferable to inject the filler without using a second shielding layer, which does not require the step of providing a second shielding layer.

In addition, the molding bodies in this case include wooden molds, metal molds, and FRP.
Various types of molds can be used, such as molds made of aluminum, rubber molds, cementitious material molds, and their shell types, but in particular, fillers such as those described in the above embodiments are used after being solidified under reduced pressure. A molded body is preferred, and the method for manufacturing the molded body will be explained below.

FIG. 5 shows a thermoplastic film 22 placed on a master mold 21 made of wood, metal, plaster, or other material and heated and molded.

At this time, the master mold 21 is provided with a large number of small holes, preferably with an average diameter of 2 mm or less, that reach the surface of the master mold, or a porous master mold having a large number of small holes is used, and the molding is performed while reducing pressure through the small holes. , it is possible to obtain a molded plastic film, ie, a shielding layer, which is closer to the original precision.

Also, of course, not only plastic films can be used for this shielding layer, but also those mentioned above can be used, and even if plastic films are used, plastic may be sprayed or painted and then solidified and molded. Many methods of forming the coating other than those shown can be used.

Further, it is also possible to attach a mold release agent to the master mold 21 to make it easier to release the master mold, or to apply a colorant or a spraying material to be transferred onto the plastic film 22.

Next, FIG. 6 shows that an outer frame 24 with filter members 23 and 23' is provided around the original well covered with the film shown in FIG. 5, and a filler 25 such as sand is injected. Although the filter member 23 does not allow fillers such as sand to pass through, cloth, honeycomb, net, or other filters that allow air to pass through may be used.

Next, as shown in FIG. 7, an air-impermeable membrane such as a plastic film 26 is placed on the filler material, and the filter member 2
The part 3 is passed through an exhaust pump to reduce the pressure of the filling material 25 in the mold, thereby solidifying the filling material.

Although the figure shows exhaust air only from the filter member 23 on the right side, it is natural that exhaust air is also exhausted from the filter member 23' on the left side, or the filter member on the left side is sealed. The same applies to the following description.

Figure 8 shows the mold in the state shown in Figure 7 turned upside down, and then the original 2
1, which can be used in the present invention, is shown. In this state, the filler 25 such as sand may be solidified under reduced pressure, and it is not necessarily necessary to exhaust the filler 25 through the filter member. There's no need to be.

However, in normal cases, there may be imperfections in the adhesion between the film 22, the outer frame 24, and the film 26, or other problems.

Because the filling material inside the mold often returns to normal pressure gradually due to lack of airtightness at the connecting part, it is preferable to exhaust the air to a reduced pressure state.

Furthermore, as mentioned in the explanation of FIG. 5, a large number of small holes are provided in the master mold 21, and the inside of the master mold is kept in a reduced pressure state from the time of molding the film 22 to the time of solidifying the filler under reduced pressure. By doing so, it is possible to maintain the film 22 in exactly the same state as the original mold 21, and in particular, it is possible to prevent the mold from becoming different from the original mold due to the film being attracted to the filling material when the filling material is depressurized. At the same time, when demolding the master mold, it is preferable to introduce pressurized air into the small holes so that the film 22 and the master mold 21 can be easily released from the mold.

In addition, even if a mold release agent is applied on the film 22 before the filler is injected as shown in FIG. 6, and then the filler is introduced, the molded product can be easily released from the mold after 4.

By using such a molding body, mass production can be easily carried out by preparing only the master mold or a predetermined mold corresponding to the master mold, and it is possible to convert molds that are expensive and time-consuming to create in a short time. It can be easily manufactured from a single prototype, and at most only a shielding layer is required for each molding, the filler, outer frame, etc. can be used repeatedly, and the shielding layer It is even possible to reuse thick plastic films that have been evenly molded, which is extremely advantageous industrially.

In addition, the prototype can be manufactured using the materials that make up the prototype, and molded products with different shapes can be molded using the same outer frame. Even in the production of cementitious molded bodies, it is possible to produce cementitious molded bodies with high productivity.

Furthermore, since the filler material can be deformed freely even though it may fall apart, molded products with complex shapes can be molded with precision, and weak parts such as thin parts are extremely unlikely to be damaged when demolding. be.

Also, although Figure 3 shows the filler being injected directly onto the cementitious material, a second shielding layer could also be provided therebetween.

The second shielding layer may be selected to have non-air permeability, air permeability, heat resistance, and other characteristics depending on the moisture content of the cementitious material, desired curing rate, heating temperature, etc.

In this case, for example, if it is desired that the back surface of the cementitious molded body (the top surface in FIG. 3) be a smooth surface, a smooth plastic film may be used.

However, if it is not particularly required, the second shielding layer is generally not provided, and moisture in the cementitious molded body is appropriately absorbed by the reduced pressure of the filler, promoting hardening of the cementitious molded body. be done.

After the cementitious molded body is aged and hardened, the filler used in this manner is recovered by releasing the reduced pressure and is reused.

In this case, when the breathable second shielding layer is used or when the second shielding layer is not used, it is preferable to reuse the recovered filler after passing through a washing step and/or a drying step.

In addition, in the above explanation, an example was shown in which a mold body for molding and a mold body for curing were used together, but the present invention provides a filter member for reducing pressure of the filler material and a means for heating the filler material in the mold body for molding. It can also be cured directly.

FIG. 9 shows another embodiment of the molded body of the present invention.

Flexible tubular filter member 31 and heating stage 3
2 provided in the filler layer 33, an outer frame 35 provided with an adjustment supply port 34 as a filler adjustment means, a sealing member 36, and a molded body 37 of cementitious material having a shielding layer made of a plastic film on the upper surface. A curing mold is shown.

The exhaust ports 38 and 38' are connected to a vacuum pump for depressurization to maintain the filling material in a reduced pressure state through a flexible tubular filter member, and the filling material 33 is heated by a heating stage 32, and the cement The molded material 37 is cured and hardened.

It is preferable to use a flexible tubular filter member because the filling material within the mold can be maintained at a uniform reduced pressure.

Further, instead of the flexible tubular filter member, a bag mold can be used to uniformly solidify the filter member.

Further, both FIG. 3 and FIG. 9 show examples in which the shielding layer is left on a molded body of cementitious material, but this may be left permanently as a decorative material or when used. This is because by peeling it off at the end of construction, etc., it is left behind to protect the transportation pipe and prevent damage during construction, and it can be removed if this is not necessary.

[Brief explanation of the drawing]

Figures 1 to 2, explanatory diagrams showing examples of the mold body of the present invention, Figures 3 to 4, diagrams illustrating implementation of the method of the present invention, Figures 5 to 8, mold body for molding. Explanatory diagram showing one manufacturing method of 9th
FIG. 2 is an explanatory diagram showing another embodiment of the molded body of the present invention. 1: Filter member, 2: Heating means, 3: Outer frame.

Claims (1)

[Claims] 1. A molded body consisting of a cementitious molded body and a filled layer which is placed on one side of the cementitious molded body and solidified by reducing the pressure of the filler part that has air permeability in the mold by exhausting air through a filter. A method for curing a cementitious molded body, which hardens the cementitious molded body by heating the cementitious molded body.