JPS5930744A - Manufacture of glass fiber reinforced mortar - 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 method for producing glass fiber reinforced mortar (hereinafter referred to as GRC) which has excellent short-term strength development and excellent surface finish.

Generally, GRC is used as wall material for buildings because it has superior bending strength, tensile strength, and toughness, as well as long-term stability and crack resistance compared to ordinary mortar plates. has been done.

() In order to manufacture RC, a method has been proposed in which a slurry mainly composed of cement and glass fibers, or a slurry to which cement rapid hardening material is added to shorten the setting time, is sprayed onto molds, etc. There is.

However, the former takes time to harden, and the latter takes more time than necessary to maintain workability and deal with equipment troubles, so it is difficult to achieve the strength required at the time of separation in continuous manufacturing. Without it, there was a drawback. In addition, heating and curing of molded bodies is also practiced, but with hot air curing, the strength decreases over a long period of time due to evaporation of water in the GRC, and with steam curing, craters are formed on the surface of the GRC due to water droplets. It lowered its value as a commercial product. In addition, much time was required since steam curing was performed after condensation.

As a result of various studies aimed at solving these drawbacks, the present inventor added solid powder consisting of calcium aluminate and gypsum, which exhibits good strength at high temperatures, as a cement rapid hardening material, and added it to hot air. We discovered that it is possible to manufacture GRC with excellent physical properties such as strength and productivity by condensing the GRC to an extent that the surface is not eroded by water droplets, and then performing steam curing and replenishing the evaporated water with hot air. , has completed the present invention.

That is, the present invention is a method for producing ORC, characterized in that a glass fiber-reinforced mortar molded body to which inorganic powder of calcium aluminate and gypsum is added is treated with hot air, and then steam-cured.

The present invention will be explained in detail below. FIG. 1 is a detailed process diagram illustrating the present invention.

First, the condensation start time on belt conveyor 1 is 5 to 60 minutes.
Spray the rapid hardening ()RC for 1 minute, preferably 10 to 30 minutes. The figure shows a method of supplying rapid hardening mortar and fiber material by spraying, but it is also possible to supply a mixture of rapid hardening mortar and fiber material by casting. It is also possible to prepare the cement mortar and the cement quick-hardening slurry separately and introduce them to a mixer immediately before spraying, and then spray the quick-hardening cement mortar while mixing, while simultaneously transporting the fiber material from the chopper gun onto a belt conveyor. Rapidly hardens when sprayed on C) RC
may be supplied.

To explain the illustrated method, rapidly hardening mortar slurry prepared in a mortar tank 2 is fed to a spraying machine 5 through a mortar pump 3 and a mortar introduction pipe 4. Normally, the compressed gas 6 is injected from a nozzle toward the belt conveyor 1, but it can also be supplied by pouring.

Simultaneously with the injection of the rapid-hardening mortar, the fiber material is ejected from the chopper gaff 7 toward the belt conveyor 1 and mixed with the rapid-hardening mortar in the air, or is sprayed after the rapid-hardening mortar is poured. To eject the fibrous material, a roving 8 of fibers is introduced into the chopper gaff 7;
It is preferable to blow this out with compressed gas 6 while cutting it into pieces of about 5 to 100 mm.

The belt conveyor 1 has a function as a formwork, and the cross-sectional shape of the belt portion is as shown in Fig. 2. By providing a side wall, rapidly hardening mortar and fibrous material can be blown onto the side wall. This makes it easy to manufacture strong composite boards. Material of belt conveyor 1, Inugisa,
Movement speed etc. can be selected arbitrarily.

Various types of Portland cement and various mixed cements can be used as the cement for preparing the rapid hardening cement mortar slurry, and this and fine aggregate are mixed in any proportion, and then water is added and pumped. Possible slurry concentration. A mixture of calcium aluminate and gypsum as a cement rapid hardening material is essential in the present invention because of the ease of adjusting the setting start time by heating and the development of strength.
A material having a CaO content of 68 to 47% by weight and being amorphous is preferable because it exhibits excellent strength.

The ratio of gypsum to calcium aluminate is 0.5
~2 times the weight, and there are no restrictions on the form of the gypsum, but ■-type anhydrite is preferred. The amount of cement hardening material is 5 to 25 parts by weight, preferably 1 part by weight based on the cement content.
It is 0 to 20% by weight. An example of the composition is 100 parts by weight of cement, 5 to 25 parts by weight of cement rapid hardening material, 50 to 200 parts by weight of fine aggregate, and 60 to 50 parts by weight of water.
This ratio is suitable from the viewpoint of mortar fluidity and strength development. In addition, by using cement water reducer,
It has a considerable effect.

A setter is used to adjust the setting start time, but the type of setter is not particularly limited and all known setters can be used.

Among them, gluconic acid and/or tartaric acid or salts thereof 5 to 20% by weight, citric acid or salts thereof 30 to 10% by weight
A mixture of 5 to 25 parts by weight of alkali carbonate is preferred because it provides a setting initiation time proportional to the amount added. The amount used is usually 0.3 to 1 part by weight based on the total of cement and cement hardening material. If it is less than 0.3%, the effect of using it will be small, and if it exceeds 1 weight strip, it may not start to set due to heating.

Examples of the fiber material include ordinary glass fibers and alkali-resistant glass fibers, but alkali-resistant glass fibers are preferred from the viewpoint of durability. The ratio of this to the cement content of the rapid hardening mortar is about 1 to 7% by weight,
It is not limited to this in any way.

The sprayed rapidly hardening GRc is molded into an arbitrary thickness by adjusting the pressure roller 9 or the vibrator 10 from below.

Next, the rapidly hardening GRC molded body is sent to a hot air tank 11, where it is treated with hot air to start solidification. The processing conditions are:
Preferably, the temperature is 40 to 100°C and the time is 5 to 60 minutes. 4
If the temperature is 0°C for less than 5 minutes, the molded body may not start to set, and if the temperature is 100'C for 60 minutes or more, the moisture in the molded body may evaporate too much. As the hot air treatment method, as shown in the figure, a method in which hot air is uniformly sprayed onto the molded body using a jet heater 12 or the like is preferable, but the method is not limited thereto.

The molded body condensed in the hot air tank 11 is then transferred to the steam tank 13.
The material is sent to a water tank and heated with steam to make it strong enough to be handled. The temperature in the steam tank 13 is 40 to 80°C, and the time is 5
It is preferable to set the heating time to 30 minutes from the viewpoint of strength development and durability. As a method for sending water vapor, a method such as sending ordinary steam through a pipe or the like so that it reaches an appropriate temperature is adopted.

Incidentally, the total curing time of warm air and steam is preferably about 15 to 40 minutes.

The handleable strength in the present invention refers to hardened GR,
It is sufficient to have a bending strength of 20 kgf/Cm2 or more using mortar that does not contain fibers and is strong enough to ensure that the cut surface does not break or remain stiff even when C is cut.

The cured ()RC carried out from the steam tank 13 is cutter 1
4, cut it to an appropriate length, and if necessary, cure it sufficiently to make it into a product.

In the present invention, the most preferable method is continuous production on a belt conveyor, but after spraying the mold surface one by one, the mold itself is placed in a hot air tank or steam tank, or hot air is jetted into the mold. A method of spraying with a heater or the like and then entering a steam tank may also be used.

As explained above, the present invention uses hot air treatment and steam curing to develop the strength of GRC in a short time without reducing its product value, and significantly improves its productivity. The effect is that products with excellent performance can be manufactured.

Next, a more detailed explanation will be given with reference to examples.

Example: 100 parts by weight of ordinary Portland cement, 70 parts by weight of No. 6 silica sand
Weight scale, 62 parts by weight of water, and cement water reducer (Kao Soap■
A cement mortar was prepared by kneading 1.5 parts by weight of the product under the trade name [Mighty 150j] using a mortar mixer.

Separately, 100 parts by weight of a cement hardening material having a CaO content of 4 degrees and a weight ratio of ■-type anhydrite of 1=2, 6 parts by weight of water, and 6 parts by weight of sodium citrate were kneaded. A hardwood slurry was prepared.

These are adjusted so that the cement quick hardening material component is 13% by weight based on the cement component in the cement mortar. 1 by feeding and compressed gas
It was sprayed onto a formwork measuring 1 m x 1 m.

At the same time, a commercially available alkali-resistant glass fiber roving was fed into a chopper gun, cut to a fiber length of 2f:Jmyn, and then sprayed with compressed gas so as to be mixed in the air with a rapidly hardening mortar. The amount of fiber was set at a ratio of 5% by weight to the cement content of the mortar.

In this way, 10 minutes after molding a rapidly hardening RC molded body with a thickness of 10m7n, hot air at 70'C was blown for 10 minutes with a jet hitter, and when condensation started, it was placed in a steam curing room at 70°C for 10 minutes. After curing, the mold was removed after being left indoors for 10 minutes. The amount of water evaporation, 1-hour bending strength, and surface finish before and after curing were observed. The 1-hour bending strength was measured using a specimen that did not contain fibers.

For comparison, similar measurements were performed on test specimens manufactured under the same compounding conditions using various curing methods.

The curing method and results are shown in the table.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing an example of the present invention, and FIG. 2 is a sectional view of a belt portion of a belt conveyor. 1 Belt conveyor 2 Mortar tank 3 Mortar pump 4 Mortar introduction pipe 5 Mortar sprayer 6 Compressed gas 7 Chopper gun 8 Glass fiber 9 Pressure roller 10 Vibration plate 11 Hot air curing tank 12 Noet heater 1
3 Steam tank 14 Cutting machine patent applicant Denki Kagaku Kogyo Co., Ltd.

Claims (1)

[Claims] A method for producing glass fiber reinforced mortar, which comprises treating a glass fiber reinforced mortar molded article with added inorganic powder consisting of calcium aluminate and gypsum with hot air and then curing it with steam.