JPS62138346A - Manufacture of fiber reinforced lath 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 [Industrial Field of Application] The present invention is reinforced with mx*. This invention relates to a method for producing lath mortar that does not cause cracks during the hardening process.

[Prior Art] Currently, lath mortar is being applied to improve the fire resistance of wooden buildings. This lath mortar is made by spreading asphalt paper on top of the base, attaching a metal mesh such as metal lath, wire lath, or riblas to the asphalt paper to improve the adhesion of the mortar coating, and then applying mortar on top of it with a trowel. There is.

[Problems to be Solved by the Invention] However, in the curing process of this lath mortar, the tensile stress acting on it exceeds the tensile strength of the mortar, and the mortar is usually divided and cracks occur.

Cracks occur during the hardening process of this mortar.

Needless to say, this is due to cracks in the cement paste in the mortar. This cracking is thought to be due to the cement paste drying and shrinking before it develops sufficient strength, and the tensile strength of the cement paste being unable to withstand the shrinkage force. Mortar cracked due to cracks in the cement paste does not form an integral structure, and rainwater and moisture infiltrate through the cracks, corroding the metal mesh such as metal lath and the base plate, and as the erosion progresses, the mortar There was a problem that it caused damage such as peeling off.

The purpose of the present invention is to prevent the occurrence of cracks during the hardening of cement paste, which is the main cause of cracks during the hardening process of mortar, so that cracks do not occur in the mortar during the hardening process, and metal mesh such as metal lath and the base An object of the present invention is to provide a method for producing fiber-reinforced lath mortar that does not cause corrosion.

[Means for Solving the Problems] The present invention involves preparing ultra-fine ultra-short lpA fibers by finely cutting non-metallic alkali-resistant fibers with a thickness of 1 to 30 l into powder form, and Short fibers are mixed with Portland cement, aggregate and water are added to this mixture and kneaded, and the kneaded mixture is troweled onto a metal mesh such as metal lath attached to the base via asphalt paper. This is a method for producing fiber-reinforced lath mortar that is cured.

Here, it is preferable that the mixing amount of the ultrafine ultrashort fibers is 0.5 to 10 parts by weight based on 100 parts by weight of cement.

[Function] By making the reinforcing fibers into ultra-fine and ultra-short fibers, the reinforcing fibers can be easily and uniformly dispersed and mixed into cement in a short time, and can also be mixed into cement, such as metal lath of mortar, which is a kneaded product. It becomes more familiar to the net.

The mortar of the present invention has increased tensile strength and does not crack during the curing process. This is thought to be because the uniformly dispersed fibers are bonded to each other by the cement paste to form a crosslinked structure, which uniformly increases the tensile strength of the cement paste.

The reinforcing fibers used in the present invention are non-metallic, alkali-resistant, ultra-fine, ultra-short JA fibers. Examples of HA fibers include general polyamide, polyvinyl alcohol, and polyolefin fibers, as well as synthetic fibers with heat resistance and high tensile strength, carbon fibers, and inorganic fibers such as silicate fibers.
a#I is mentioned.

However, this inorganic fiber does not contain metal fibers that cause rust.The reinforcing fiber of the present invention has a diameter of 1 to 30 mm.
It is an ultra-short llU fiber obtained by finely cutting gm tam into powdered pieces with a length of about 1 mm. The amount of reinforcing fiber mixed with cement is 0.5 to 1 per 100 parts by weight of cement.
It is selected within the range of 0 parts by weight.

A mortar is prepared by mixing cement with reinforcing powder, and adding aggregate and water to the mixture and kneading it.

The mixing amounts of aggregate and water to cement are the same as in conventional manufacturing methods. Fine aggregate sand is used as the aggregate. Here, since the reinforcing fibers are ultra-fine, ultra-short fibers, they are uniformly dispersed in the cement by short-time stirring, and do not form fiber poles like conventional warped reinforcing fibers.

The mortar kneaded in the above weight ratio is spread over asphalt paper on a base, and troweled onto a metal mesh such as metal lath, wire lath, riblas, etc. attached to the asphalt paper. Since the reinforcing fibers of mortar applied with a trowel are in a form that is easy to flow, it can be easily applied onto metal mesh such as metal lath, and even if this mortar is hardened without special curing,
Reinforcing fibers bond to each other in the cement paste to increase tensile strength and prevent cracking.

[Effects of the Invention] As described above, according to the present invention, by making the reinforcing fibers extremely thin and short, mortar is created in which the reinforcing fibers are extremely uniformly dispersed in the cement, which makes it difficult to spread the reinforcing fibers into the metal mesh such as metal lath. Easy to apply with a trowel.

In addition, in the mortar of the present invention, the reinforcing w & fibers are uniformly dispersed in the mortar and are bonded to each other using cement paste as a binding material, so even if one mortar suffers coagulation shrinkage or drying shrinkage, it is absorbed by the reinforcing fibers, and the special Even without curing, it is possible to completely prevent cracking during the curing process, which is a fatal defect of conventional lath mortar. Furthermore, since the reinforcing fibers are alkali-resistant, they do not deteriorate easily in the mortar, and since they are not metal fibers, they do not corrode due to rust, and the texture of the mortar surface is fine.

From these facts, the lath mortar manufactured according to the present invention has excellent effects such as no corrosion of the metal mesh such as metal lath or base plate caused by cracks, and no loss of beauty of the mortar surface. be.

[Example] 100 parts by weight of ordinary Portland cement, 1 m in length
1.5 parts by weight of vinylon fiber with a thickness of 18 g rrr (1.8 denier) were mixed uniformly, 200 parts by weight of river sand with a maximum particle size of 1 hm was added to this mixture, and the water-cement ratio (W/C ) 81% and thoroughly kneaded to prepare mortar.

9mm thick on a block wall installed outdoors.
A 92 cm x 180 cm lauan plywood board was pasted as a base board, asphalt paper was pasted, and metal lath was attached on top of it.

The mortar was troweled onto this metal lath to form a mortar layer with a thickness of 10 m+w.

[Comparative example] Without using the vinylon fiber of the example, 200 parts by weight of river sand with a maximum particle size of 10 mm was added to 100 parts by weight of ordinary Portland cement, and the water-cement ratio (W/C) was 50%.
A mortar was prepared by thoroughly kneading the mixture.

The above mortar was applied with a trowel onto the base plate, asphalt paper, and metal lath constructed in the same manner as in the example, to a thickness of 10 m.
A mortar layer of m was formed.

[Test results] Several long cracks appeared on the surface of the mortar layer in the mortar of the comparative example within a few days, whereas the mortar of the example did not show any cracks even after 28 days. , did not occur.

Claims (1)

[Claims] 1) Finely cut non-metallic alkali-resistant fibers with a thickness of 1 to 30 μm into powder to prepare ultra-fine ultra-short fibers, and mix the ultra-fine ultra-short fibers with Portland cement; A method for producing fiber-reinforced lath mortar, in which aggregate and water are added to this mixture and kneaded, the kneaded mixture is troweled onto lath attached to a base via asphalt paper, and then cured. 2) The method for producing fiber-reinforced lath mortar according to claim 1, wherein the amount of ultra-fine ultra-short fibers mixed is 0.5 to 10 parts by weight per 100 parts by weight of cement.