JPS5813849A - Reinforcing and repairing of slate roof - 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 utilizes slate, which has deteriorated in physical properties due to age, as a lid frame for a base panel in a Sleet 1111 structure, and removes the top surface of the slate without essentially cleaning the top surface. A slate shop @ 0 strengthening repair method characterized by spraying a synthetic resin emulsion and sun-mixed cement mortar to a thickness of 2 to 6 sm (1) to form a new slate layer.

Today, slate (6 to 12 mm thick), which is made of cement mixed with asbestos and other fibers, is widely used for equipment such as factories, railway platforms, and warehouses.

Generally, this type of slate is said to have a lifespan of F120 years, but in places with harsh climate and atmospheric conditions, such as industrial areas on the coast, cars often notice that their strength steadily declines over 10 years. . Especially in recent years, the generation of sulfur dioxide gas has increased due to the increase in the number of industrial furnaces that use heavy oil and the number of automobiles that use gasoline as fuel. Characteristic 0 deterioration is progressing. Deterioration ← Asbestos slate has a large amount of asbestos powder attached to its surface in an unstable state. Considering that asbestos is designated as a strong carcinogen, measures to prevent its dispersion are required. must be implemented as soon as possible.

One way to deal with this is to replace the slate with a new one, but it requires complete curing with sheet slate to prevent stains inside the building and damage to machinery and equipment. 2) Factories, etc. will have to close for several days for roof replacement and construction work.

8) j1 It is difficult to dispose of a large amount of deteriorated slate waste. 4) Most asbestos is imported, and its price is high, which goes against the national policy of conserving resources. There are a number of problems that are piling up.

Furthermore, as an advanced measure, several methods and materials for repairing and regenerating deteriorated slate have been introduced. Among these methods, one that has been widely used recently is the method of mixing cationic SBR latex with cement. This is done by thoroughly washing the deteriorated slate roof with water, mixing cationic styrene-butadiene rubber-based 2Tex into a mixture of cement and silica, and spraying it onto the slate to create a permeable bond and strengthen it. This method increases the construction thickness from 0.5 to
It is about 2.0 cod. (This has been published as an application by Nippon Gosei Rubber Co., Ltd.) B) The deteriorated surface is washed with high-pressure water using the so-called rift method, and a sodium silicate-based aqueous solution, a lithium hydroxide aqueous solution, or a lithium sulfate solution is used. Another method is to impregnate deteriorated slate with a solution containing an alkali metal component to strengthen the slate. (This was patented by Nyoshi Kagaku Kogyo Co., Ltd. as ``Binding agent'' r coat bonding method'' and ``Method for preventing deterioration of both surfaces of inorganic materials'' and Japanese Patent Publication No. 50-80658 and Japanese Patent Publication No. 50-2162, respectively. (The patent application was published as Japanese Patent Publication No. 15B-19609.) Furthermore, there is a method of combining the above-mentioned cationic latex cement spraying with the rift construction method, but in any method of regenerating deteriorated slate, the penetrating binder is absorbed into the slate. If it penetrates into the slate sufficiently, an increase in the strength of the slate can be expected. However, as described earlier, the cement content in the slate is dissolved and washed away by the sulfite force in the surface layer of the slate.
Because the layer of fine asbestos is laminated in a mesh pattern to a thickness of several centimeters, cement resin paste mixed with synthetic resin separates only the water, making it difficult to bond it to the remaining slate base. Also, since the water is separated, the strength of the resin paste is insufficient. Also, although sodium silicate paste is a material that penetrates well into degraded slate, the strength of the paste is greatly influenced by the quality of washing with water. Therefore, there is a large amount of dust: R-producing factory I! A sufficient improvement in surface strength cannot be expected for slates used for industrial purposes.

In order to completely implement these methods, it is essential to thoroughly clean the surface of the slate to be repaired using high-pressure water, but since slate is not a flat plate but has a corrugated shape, complete cleaning is not easy. In particular, cleaning slate from bauxite smelting plants and steel factories where dust has accumulated is extremely difficult. Also, high-pressure water washing can further damage deteriorated slate, making cleaning work dangerous.

With the synthetic resin emulsion mixed cement mortar of the present invention, deteriorated slate can be used as a new formwork, eliminating it all at once.
This method strengthens and repairs deteriorated slate by simply and reliably forming a new slate based on the deteriorated slate without stopping work at the factory.

More specifically, the unique idea of the present invention is that acrylic copolymer resin emulsion, vinyl acetate copolymer emulsion,
A synthetic resin emulsion such as synthetic rubber latex is mixed with cement and aggregate to strengthen and repair the slate thin layer finish, and the deteriorated slate is used as a formwork for the base panel, and the surface is coated with 2-6-6 Spray coat to the thickness of
The point is to form a new slate layer regardless of its adhesion to the deteriorated slate.

The present invention will be explained based on the drawings. FIG. 1 is a cross-sectional view showing a slate laminated structure formed by a construction method as an embodiment of the present invention, and FIG. FIG. 3 is a cross-sectional view showing a laminated structure of slate.

Regarding the slate roof 1, there is a provision for the permissible limit of a 25'// live load on the steel frame 2 in Article 84 of the Building Standards Act Enforcement Ordinance for fixed loads in structural calculations, and the heaviest large wave asbestos slate is 12.8%, and there is a load margin for using 12.7Vd slate reinforcement repair material between them.Assuming that the specific gravity of cement mortar mixed with synthetic resin is approximately 20, the maximum thickness for construction is It will be approximately 6.8m. Furthermore, the weight has been reduced by the loss of 10Fi, and the safety level has increased accordingly.

The cement used in the present invention is generally widely used bolt cement, white cement, etc. O-acrylic copolymer resins include emulsion polymers of polymethyl methacrylate, polyalkyl methacrylate, polyethyl methacrylate, and methyl methacrylate. -In addition to acrylic copolymers containing copolymers such as styrene, methyl methacrylate and alpha methyl styrene, vinyl acetate,
Vinyl emulsions such as vinyl chloride, Beover, ethylene vinyl acetate copolymer, nuthylene-butadiene,
Synthetic rubber latexes such as chloroprene and NBR are preferably used from the viewpoint of weather resistance and water resistance. In addition to the above-mentioned synthetic resin emulsion and cement, there are aggregates, fibers, and additives that can be mixed as a slate reinforcing and repairing material.

Light aggregates such as No. 8 to 7 borax, perlite, and pumice, as well as fine aggregates such as river sand and crushed stone powder, are used as aggregates, but dry borax of No. 4 to No. 6 is used. Ink.

The fibers are alkali-resistant ceramic and glass fibers.
It is also possible to use fibers with a length of 80 to 50 days, or fibers of nylon, vinylon, or polypropylene. Generally ceramic number glass fiber is 0.8~
A 0.61 length 20-4o denier is easy to use. Furthermore, depending on the situation, water reducing agents, penetrating agents, stabilizers, thickeners, antifoaming agents, etc. may be used in combination as additives, but among these, water reducing agents are the most important. When spraying, it is preferable to use an appropriate amount of a water-reducing agent, such as a gluenins derivative or a water-soluble salt of a betaine or indacillin surfactant, since less moisture causes less shrinkage and less cracking. . This allows the amount of water to be reduced by 40 to 46% by weight compared to cement. If too large a quantity is mixed in, the stability of the synthetic resin emulsion will deteriorate, so care must be taken. When this slate reinforcing repair material is sent to high places with a hose, popal, sodium ginate, Metrose, etc. are used as thickeners to prevent the mixture from separating. There is no need to add it if it is sent to a height that does not cause separation.

The weight ratio of the cement, synthetic resin emulsion, aggregate, and fines to be mixed is 100 parts of cement and acrylic F.
The resin solid content of the resin emulsion is 5 to 40 parts, and the aggregate is 16 parts.
The amount is in the range of 0 to 400 parts, and the fiber is in the range of 0.5 part or less. Acrylate resin emulsion is a cement 1 resin solid component.
If the amount is less than 5 parts per 00 parts, the moisture in the sprayed mortar will evaporate quickly and the strength will deteriorate, and if it exceeds 40 parts, it will be too soft and uneconomical in terms of price.

If the aggregate is less than 1.5 parts by weight of cement, there is too much cement and cracks are likely to occur after drying.
If it exceeds 0 parts, there will be many voids and drying will be too rapid, making it impossible to obtain sufficient strength of the resin mortar. The fiber wire to cement weight ratio used is less than 0.6 parts, and if it exceeds this, the spray will form lumps in the hose during operation and will be difficult to transport. The viscosity of mortar is moderate with slump of 16mg or less up to 82-, and slump of 16c.
If the viscosity exceeds m, the viscosity will be too high and transportation by hose or spraying will be difficult. If it is less than 127182011, the solid content such as aggregate and the liquid valve such as synthetic resin emulsion tend to separate in the hose, and the hose becomes clogged, making it impossible to perform the work.

The gist of the method for repairing a deteriorated slate roof 1 using a reinforcing repair material of 9 slate mixed in an appropriate component ratio and viscosity as described above is to use an old slate roof 10 that is deteriorated and has a 9 surface layer 11 as a base panel. The construction method involves spraying the reinforcing repair material on the upper surface and allowing it to separate from the old slate to form a new slate 20 made of the reinforcing repair material.

The specific steps are l) To prevent the repair worker from falling, take safety measures by stretching a round fishing net or installing footboards in parallel -02) As a ground preparation, the 9th part of the hole should be filled with a large hole (approximately 20 to 801 or more), cut a slate of the same shape into a larger hole, apply an adhesive such as cement paste to the back side, and press it hard to close it. In the case of a small hole, cut cheesecloth, Glasstalos, or punch carpet to an appropriate size, dip or apply the above-mentioned spray reinforcing repair material, and then tighten it over the hole.

8) Inspect the bolts 8 and 4 that hold the old hJ ray) 10 in place, tighten any loose ones appropriately, and replace any that have fallen off with new bolts and nuts.

4) As shown in No. 111, a hole is made at the top for the bolt to pass through, and the good quality bell-shaped cap 6 is filled with spray reinforcement repair material, and the bolt 8 is covered and waterproofed from the top of 4D. conduct. (Jin's work 1 may be applied in the final process as shown in No. 211.) b) Spraying is done by machine, and general solutar spraying is done with a pressure tank; Mix compressed air and liquid reinforced repair material, and perform spraying. Pressure feeding can be done using a piston ring and a 72-diameter pump, and the pressure should be between 60 and 880;
Use at a pressure of 4 or more and 4 to γ vertical pressure. Construction capacity is O
]~1. O1I/Hr 60-200 with average thickness of 6cm
(/Hr is the range that can be applied; if the speed exceeds this speed, it is difficult to spray to a uniform thickness, and it is dangerous when using scaffolding at high places.

The key to spraying is 46mm for the wavy ridges of the slate.
Reciprocating spraying is carried out at an angle of 2° to obtain a predetermined thickness of 2 to 6 cm. Care must be taken in areas where the construction thickness is 1 to 2 mO, as sufficient strength will not be achieved.

The strength of the newly formed synthetic resin emulsion-containing cement:/t%kp reinforced repair material applied according to the above-mentioned construction procedure and method (2012) was as follows.

[Example] Weight mixing ratio Portland cement 10 parts Ethylene-vinyl acetate copolymer emulsion (solid equivalent: 50 inches) 4 #5 silica sand 15 #6 silica sand 151/Cerakix fiber (lam length, 8o denier) 0.05
&Likuninsulfone II/-/
0.1 η water
8. o# Using a cement mortar reinforcement repair material made of the above mixed components, it was applied to the top surface of a deteriorated slate roof using a mortar pump and a 211 compressor at a ratio of about 6 to about 160'4 speed. After drying in the air under sunlight for 28 days, we conducted a 6-point thickness test on the 100-inch medium circundum and found that it was L5m! 1.1sm
, 12 m, 8.5 m, and 8.6 sm. These tensile strengths are within the range of 25 to 80 vertices, and compared to the tensile strength of new asbestos slate lO~12Q/-,
It had more than twice the strength.

By the way, the slate 9) 10 used for repair had been used on the coast of Amagasaki City, Hyogo Prefecture for 18 years, and the tensile strength of this deteriorated slate had decreased to θ~2λ−. The tensile strength of this slate reinforced with cationic styrene-butadiene mortar cement is 8.
The tensile strength of ~10 wheels reinforced with sodium silicate straw material was 6-81.

As described above, according to the method for strengthening and repairing slate roofs of the present invention, there is no need to remove deteriorated slates, and therefore, there is no need to suspend work at the factory, making it possible to easily and economically strengthen and repair slate roofs. If implemented, the effect it will have on the industry will be significant.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the laminated structure of slate formed by a construction method as an embodiment of the present invention, and FIG. FIG. (Explanation of symbols) IO...deteriorated slate), 11...deteriorated slate surface layer, 20...new slate. -That's all-

Claims (1)

[Claims] 1. In slate roof structures, the physical properties of the slate have deteriorated over time, and the slate is used as a cover frame for the base panel, and mK2 is applied over the top surface without essentially cleaning the top surface.
A method for strengthening and repairing slate roofs, which is characterized by spraying cement rutal mixed with a synthetic resin emulsion to a thickness of ~6cm to form a new slate layer.