JP3759014B2 - Method of curing concrete body and curing composition - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a curing method for a concrete structure or a molded article (hereinafter referred to as a concrete body), and more particularly to an improvement technique for a wet curing method for a concrete structure.
[0002]
[Prior art]
The concrete body is required to exhibit predetermined strength and durability after being placed and cured. When concrete is affected by harmful effects such as low temperature, drying, and sudden temperature changes during curing, the strength and durability of the concrete decrease. For this reason, it is necessary to cure the concrete surface before curing to fully exhibit strength and durability.
[0003]
That is, in the curing method of the concrete body, it is desirable to keep the surface of the concrete body in an appropriate wet state so as not to dry, and a method of covering the surface with a curing sheet or the like is adopted. For example, the following techniques are known.
(A) In JP-A-6-212799 (hereinafter referred to as A), a water-absorbing curing sheet is mounted on the surface of a concrete body in a wet state after removing a concrete formwork, and then water is supplied. There is shown a curing method for a concrete body in which the sheet is swollen with water to adhere to the concrete surface and the concrete surface is maintained in a wet state during the curing period, and then the sheet is peeled off.
(B) In Japanese Laid-Open Patent Publication No. 10-61184 (hereinafter referred to as “B”), in the curing method of a cast concrete body, the surface of the concrete body is removed after removing the formwork for forming the concrete body. Discloses a method for curing a concrete body in which a sheet made of an adhesive and a moisture-impermeable synthetic resin film is attached.
(C) Japanese Patent Application Laid-Open No. 6-285832 (hereinafter referred to as C) discloses a heat insulating mat having a heat insulating member and a waterproof sheet member that encloses the periphery of the heat insulating member, and one surface of the heat insulating mat. A concrete curing mat is disclosed that includes a wet mat provided.
[0004]
[Problems to be solved by the invention]
However, the above conventional technique has the following problems.
(1) In the technology for supplying water to the water-absorbing curing sheet mounted on the surface of the concrete body described in the A publication, and causing the sheet to swell with water and adhere to the surface of the concrete body, the water-absorbing curing sheet is attached to the surface of the concrete body. It takes a lot of man-hours to attach to the wall, and it is difficult to cover the surface of the concrete body having an intricate shape without a gap, resulting in lack of workability. Moreover, the part which was not covered deteriorated in intensity | strength, and the subject that the reliability of the intensity | strength of a concrete body was reduced occurred.
(2) Further, there is a problem that the water-absorbing curing sheet is partially peeled during the curing of the sheet, and the surface coating is not reliable, which causes cracks and cracks.
(3) In the curing method for adhering a sheet made of an adhesive and a synthetic resin film described in the bulletin, it is easy to accurately paste a wide sheet with an adhesive on the surface of a concrete body in the field. In addition, the work is cumbersome and lacks workability, the sheet is detached due to adhesion spots, the sheets partially overlap, and air-containing cavities are generated, and the curing condition of the concrete body becomes uneven and the curing is There was a problem that defects were likely to occur.
(4) In the concrete curing mat described in the publication No. C, the mat has a multi-layered structure, so it takes time to manufacture, lacks economic efficiency, and the shape of the mat is limited to a simple shape such as a rectangular shape. There is a problem that it is difficult to apply to a structure of a simple shape and the versatility is poor.
[0005]
The present invention has been made to solve the above-mentioned problems, and provides a curing method for a concrete body having excellent workability that can be applied to a concrete body having a complicated shape with a small number of work steps, and surface coverage after construction. An object of the present invention is to provide a curing composition that is excellent in economy and versatility without causing poor curing such as cracks and cracks.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configuration.
The method for curing a concrete body according to claim 1 includes: a binding agent formed with water and a synthetic adhesive such as polyvinyl acetate, or a natural adhesive such as starch, paper pulp, waste paper, sawdust, cellulose fiber, and protein fiber. , A step of spraying a curing composition containing a fiber component made of a pulverized inorganic fiber onto the surface of a concrete body before curing after removing the formwork, and forming a curing coating layer on the top surface of the uppermost portion of the curing coating layer Spraying water from a water supply tubular body having a large number of water passage holes disposed along the uppermost portion to maintain the curing coating layer in a wet state.
With this configuration, the following effects can be obtained.
(A) A curing coating layer can be easily formed just by spraying a curing composition on the surface of a concrete body, and can be applied to a concrete body with a large-scale and complicated structure to perform continuous construction. Excellent workability.
(B) The curing coating layer can be composed of fibers and binders that are not harmful to the environment, and after curing, the curing coating layer is sprayed with washing water or vacuum suction. It is possible to easily carry out the post-processing to remove the.
(C) Natural binders such as starch and cellulose, which are harmless to the environment, can be applied to the binder and fibers, and they are not decomposed by bacteria in the soil to pollute the environment. Excellent retention.
(D) Since there is a step of constantly maintaining the curing coating layer in a wet state by spraying water from the water passage holes, there is no difference in shrinkage due to drying of the concrete body, which is effective in generating cracks and the like. Can be prevented.
(E) Since the sprayed curing composition has appropriate caking properties and water retention, a curing coating layer can be easily and uniformly formed on the wall or ceiling of a vertically erected concrete body. Can do. The fiber is entangled with minute irregularities on the surface of the concrete body and has excellent retention. In addition, since the binder is a water-soluble polymer, it is compatible with the concrete body and penetrates into the fine pores, and is concentrated by the heat of the concrete body in the deep part of the pores, so that the fiber content can be held by the adhesive strength.
(F) Since the curing coating layer has water-retaining fibers, water that is sprayed from the water supply tubular body can be easily absorbed, and moisture can be concentrated in one place by the capillary tissue formed between the fibers. And can be dispersed over a wide range. As a result, the surface of the concrete body can be maintained in a wet state with a minimum amount of water, and can be cured until predetermined strength and durability necessary for the structure are provided.
(G) Since the curing coating layer is sprayed and applied to the surface of the concrete body without causing cavities and the like, a concrete body free from cracks on the surface having no variation in curing conditions and having no defects in strength can be obtained.
(H) Since the water-absorbing tubular body is flexible, it can be easily placed on the top of the concrete body, etc., and can be automatically supplied with water. Since the surface can be maintained in a proper wet state, it is excellent in economic efficiency.
[0007]
Here, the curing composition is in the form of a caking fluid solution or slurry having a predetermined amount of moisture, caking agent, and fiber, respectively.
As the binder, water-soluble synthetic adhesives and natural adhesives are used alone or in combination. This is because it can be easily washed away after curing. As the synthetic adhesive, polyvinyl acetate and its copolymer, acrylic adhesive, ethylene-vinyl acetate copolymer, nitrile rubber, epoxy resin, chlorinated polypropylene, etc. are used, especially those with excellent water solubility. preferable. As the natural adhesive, starch, dextrin, gum arabic and the like can be applied. In particular, it is preferable to use a polyvinyl acetate adhesive or a natural adhesive as a synthetic adhesive because it is easily decomposed into bacteria.
The binder may be used in combination with one or more different components, and those having a predetermined viscosity required for spraying can be obtained by the mixing ratio thereof, and the rebound loss during spraying and the curing composition can be obtained. The spraying operation can be set to its proper state by adjusting the amount of sag from the vertical wall surface.
In addition, when mixing a synthetic adhesive and a natural adhesive and making it a binder, it is preferable to make the content rate with respect to all the adhesives of a synthetic adhesive into the range of 90 weight% or less.
Examples of the fiber component include those made of synthetic resin such as nylon, polyester, and polyethylene, and natural fibers made from pulverized materials of paper pulp, waste paper, sawdust, cellulose fibers, protein fibers, and inorganic fibers. From the viewpoint of environmental resistance, natural fibers such as paper pulp, waste paper, and sawdust are preferably used. When sawdust is used, the size is 0.05 to 3 mm, water is absorbed and swollen, and a dense coating layer can be formed as a whole. Product name: Gifu Applied Materials Co., Ltd .: seed spray curing materials such as Oyo Fiber can be applied.
[0008]
As the cellulose fibers, seed fibers such as cotton and kapok, bast fibers such as flax, cannabis, jute and ramie, and leaf vein fibers such as manila hemp and zycal hemp are used. As the protein fiber, wool fiber such as wool, cashmere, mohair, alpaca, camel hair, silk fiber, feather fiber and the like can be used.
The thickness of the curing coating layer is 1 to 10 mm, preferably 3 to 6 mm. This depends on environmental conditions such as the thickness of the concrete body, type of cement, temperature and humidity, but as the thickness becomes thinner than 3 mm, the moisture content evaporates through the curing coating layer, so the coating effect decreases and the curing is poor. On the contrary, as the thickness exceeds 6 mm, the material cost increases and the tendency to peel easily appears. Moreover, since these tendency will become more remarkable when it becomes less than 1 mm or more than 10 mm, it is not preferable.
For spraying the curing composition, for example, a mixed solution obtained by dispersing or dissolving a predetermined amount of fiber and binder in water using a kneader such as a mortar mixer is stored in a container having a nozzle at the bottom. And it can carry out using spraying apparatuses, such as a hydro seeder and a spray nozzle which spray in a mist form by blowing compressed air toward a nozzle hole from the secondary nozzle arrange | positioned inside the said nozzle.
[0009]
Although it depends on the area to be sprayed and the type of the binder and fiber, it is desirable to spray each so as to have an appropriate distribution amount. For example, it is preferable to adjust the binder to a range of 1 to 25 parts by weight, a fiber content of 15 to 80 parts by weight, and an added moisture of 200 to 800 parts by weight. When the amount of the binder is less than 1 part by weight, the binding property is insufficient and when the amount exceeds 25 parts by weight, the spraying workability tends to deteriorate. In particular, the binder of 2.5 to 10 parts by weight is preferable because it excels in the anchoring effect on the concrete wall surface and is excellent in fiber retention. If the fiber content is less than 15 parts by weight, water retention and the like are insufficient, and conversely if it exceeds 80 parts by weight, the spraying workability tends to deteriorate due to rebound loss and the like, which is not preferable. A fiber content of 20 to 60 parts by weight is particularly preferable because rebound loss and sagging can be prevented. Further, although depending on the binder used, the type of fiber, and the like, it is not preferable that the added water is less than 200 parts by weight because the dispersibility of the fiber tends to deteriorate, and conversely, the added water is 800 wt. Exceeding the portion is not preferable because the amount of water flowing out to the surrounding environment exceeds the amount of water that can be retained by the curing coating layer. In particular, although there are some fluctuations depending on the binder and the fiber content, when the water content is 250 to 600 parts by weight, the dispersibility of the fiber content is excellent, and the rebound loss and sag are less suitable.
[0010]
The water supply tubular body is composed of a vinyl hose, a rubber hose, a metal pipe, or the like, and seals one end thereof, and water such as tap water is supplied at a predetermined pressure from the other end. The diameter of the water passage holes is about 0.05 to 1 mm, and the water passage holes are arranged in a staggered pattern or in a row at predetermined intervals, for example, 5 to 100 mm.
It should be noted that the water that is dripped or sprinkled from the water passage holes contains a curing accelerator that accelerates the curing of the concrete and the binder, and an antibacterial agent component that suppresses the generation of mold, moss, and the like. It is also possible to adjust the curing environment and conditions of concrete.
[0011]
The method for curing a concrete body according to claim 2 includes a step of covering the surface of the concrete body before curing with a form sheet removed with a mesh sheet, and natural adhesion such as moisture and vinyl acetate resin or starch on the mesh sheet. A step of spraying a caking composition containing an adhesive binder to form a curing coating layer including the mesh sheet, and a plurality of upper layers disposed on the uppermost surface of the curing coating layer along the uppermost portion. And a step of sprinkling water from a water supply tubular body having water passage holes to maintain the curing coating layer in a wet state.
With this configuration, the following effects can be obtained.
(A) A curing coating layer containing a net-like sheet is formed on the surface of the concrete body, the strength of the curing coating layer having water retention can be increased, and the surface of the concrete body can be protected from drying, impact, etc. over a long period of time. .
(B) Since a net-like sheet having fine irregularities and fluffs is arranged, the adhesion when spraying the caking composition is good, and the anchoring effect is good and the rebound loss is reduced, making it economical. Excellent.
(C) Since the net-like sheet becomes resistant to the caking composition flowing down the surface of the concrete body, the caking composition can be fixed in the meantime to form a curing coating layer having a uniform structure.
(D) Since moisture is supplied through the water supply tubular body and the curing coating layer can be maintained in a wet state with a minimum amount of moisture, it is excellent in stability maintenance and economics of curing conditions.
(E) The curing coating layer can be composed of a water-soluble starch-based binder that is less harmful to the environment, can be easily washed away after curing, and the curing coating layer is removed. Excellent environmental preservation.
(F) When removing the curing coating layer, since the net-like sheet is contained as a core material, the entire curing coating layer can be easily peeled off, and the workability is excellent.
(G) Placing a reticulated sheet on the surface of the concrete body, and spraying moisture on it, softens the reticulated sheet with a binder and adheres it to the surface of the concrete body to form a curing coating layer. Therefore, the construction can be performed very easily and the workability is excellent.
(H) Since the curing coating layer including the net-like sheet formed by adhering to the surface of the concrete body can be made uniform, variations in temperature and humidity are suppressed, and the curing conditions can be maintained satisfactorily.
(I) When removing the curing coating layer, the entire curing coating layer can be easily peeled off, and the workability is excellent.
(J) Since water droplets are constantly supplied to the curing coating layer and maintained in a wet state, there is no difference in shrinkage due to drying, and the occurrence of cracks and the like can be effectively prevented.
(K) Since it is only necessary to arrange the water supply tubular body on the upper part of the mesh sheet, the installation is easy, and the surface of the concrete body can be maintained in a proper wet state with a small amount of water, which is excellent in economy.
Here, as the net-like sheet, a net-like body made of a non-woven fabric or a woven fabric made of a long-fiber synthetic fiber such as polyester, nylon, or acrylic or a natural fiber such as cellulose is used.
The spacing between the fibers constituting the mesh sheet (mesh spacing) is set, for example, in the range of 0.01 to 3 mm, preferably 0.1 to 1 mm. As the mesh spacing becomes less than 0.1 mm, the mesh tends to clog too much and the adhesion of the caking composition tends to decrease. Conversely, as the net spacing exceeds 1 mm, the holding power and the overall strength of the caking composition decrease. Since these tendencies become less remarkable when they are smaller than 0.01 mm or larger than 3 mm, they are not preferable. In addition, as an example of such a net-like sheet, for example, Bennett or the like manufactured by Asahi Kasei Kogyo Co., Ltd. for vegetation construction, which is made of 100% cellulose and is a non-binder long-fiber nonwoven fabric by the spun pond method, is suitable. Used.
The operation of spraying the caking composition can be performed using a spraying device such as a hydroseeder or a power sprayer that sprays the caking composition using compressed air.
[0012]
The curing method for a concrete body according to claim 3 is the invention according to claim 1 or 2, wherein the content of the binder in the curing coating layer is 10 to 100 g / m. ² It is comprised so that.
With this configuration, in addition to the operation of the first or second aspect, the following operation can be obtained.
(A) Since the content of the binder in the curing composition is adjusted to a specific range, rebound loss and poor adhesion when spraying the curing composition onto the surface of the concrete body are suppressed, and work during construction Can be improved.
(B) Since the viscosity of the curing composition falls within a predetermined range, a constant amount of the curing composition can be sprayed to the surface of the concrete body at all times, and a curing coating layer having a certain thickness can be formed, and its construction management Can be done easily.
Here, the content of the binder is 10 g / m ² If the amount is less, the curing composition is insufficient in tackiness, rebound loss increases, and the economy is low, conversely 100 g / m ² Exceeding the viscosity is not preferable because the viscosity increases, the power required for spraying increases and the density of the cured coating layer formed varies. In particular, 10-60 g / m ² In this case, it varies somewhat depending on the temperature or the like, but it is suitable with little rebound loss and sagging.
[0013]
The concrete body curing method according to claim 4 is the invention according to claim 2 or 3, wherein the mesh sheet is formed of a natural fiber such as cotton or a long-fiber nonwoven fabric made of a water-absorbing polymer resin. ing.
With this configuration, in addition to the effects of the second or third aspect, the following actions can be obtained.
(A) Since the net-like sheet is made of a long-fiber nonwoven fabric such as natural fiber or water-absorbing polymer resin, the caking composition to be sprayed can be efficiently captured, and the rebound loss is reduced and the economy is excellent. .
(B) Capillary structure excellent in water absorption can be formed in the curing coating layer, and the moisture of the water droplets sprayed in a dotted manner is spread over a wide range to maintain the entire curing coating layer in a uniform wet state. And can be easily maintained.
(C) Since water retention is imparted to the curing coating layer, it is possible to minimize the amount of water spray necessary for maintaining the wet state, thereby suppressing the influence on the environment.
(D) By using a non-woven fabric having a fluffy surface, it is possible to improve the adhesion even to the surface of a concrete body having a smooth surface by using a decorative plywood as a concrete mold material.
Here, as natural fibers of long fibers, fibers such as cellulose having a length of 10 mm or more are preferably used. In addition, the water-absorbing polymer resin includes starch-based starch-polymerized acrylate, cellulose-based carboxycellulose acrylate-grafted, acrylic acid / vinyl alcohol copolymer, acrylic acid polymer. Acrylic acid / acrylamide polymer, a modified polyethylene oxide, or a combination thereof can be used.
[0014]
The concrete body curing method according to claim 5 is the invention according to any one of claims 2 to 4, wherein the water supply tubular body is upper by a partition portion extending in a longitudinal direction of an inner center thereof. The pressurized water supplied to the lower water passing portion is divided into a water passing portion and a lower water passing portion, passes through a distribution hole formed in the partition portion, and flows into the upper water passing portion. Water is sprinkled from the water passage holes provided at predetermined intervals on the upper part.
With this configuration, in addition to the operation of any one of claims 2 to 4, the following operation is obtained.
(A) Since the pressurized water supplied to the lower water flow portion passes through the distribution hole formed in the partition portion and flows into the upper water flow portion, the pressure water is provided at the upper part of the pressure-equalized upper water flow portion. Water can be uniformly discharged toward the outside from the water passage hole, and the curing coating layer over a wide range can be efficiently maintained in a wet state.
(B) Since the water passage holes are provided in the upper part of the upper water passage at predetermined intervals, the water can be retained without causing the binder to flow out from the curing coating layer with a small amount of water continuously discharged. The curing coating layer can be maintained well.
[0015]
The method for curing a concrete body according to claim 6 includes: water, a binder made of a synthetic adhesive such as polyvinyl acetate, or a natural adhesive such as starch, paper pulp, waste paper, sawdust, natural fiber, inorganic fiber. A step of spraying a curing composition containing fibers from the ground material onto the surface of the concrete body before curing removed from the mold to form a curing coating layer, and drying and solidifying the curing coating layer to form a heat insulation layer And maintaining the surface of the concrete body in a heat-retaining state.
With this configuration, the following effects can be obtained.
(A) A curing composition containing moisture, a binder, and fibers is sprayed onto the surface of the concrete body to form a curing coating layer, and the curing coating layer is dried and solidified to form a heat insulation layer, and the surface of the concrete body is Since the insulation temperature is maintained, even if the temperature at the construction site drops below zero degrees, the heat-absorbing curing coating layer effectively suppresses heat dissipation from the hydration heat that accompanies concrete hardening, and defects due to freezing occur in the concrete structure. It can be prevented from occurring in objects.
(B) Since the curing coating layer can be formed from the fiber fixed with the binder, it can be used as a heat insulating layer on the surface of the concrete body excellent in heat insulation.
(C) Since the curing coating layer is fixed with a binder, it can be easily removed by being wetted with water after drying, and is excellent in workability during removal.
[0016]
The curing composition according to claim 7 comprises a binder formed of a natural adhesive such as a synthetic adhesive or starch, and a pulverized product of paper pulp, waste paper, sawdust, cellulose fiber, protein fiber, and inorganic fiber. A curing composition for forming a curing coating layer on a concrete body containing fiber, wherein the binder is 1 to 25 parts by weight, the fiber is 15 to 80 parts by weight, and the added water is 200 to 800 parts by weight. It is comprised so that it may be a part.
With this configuration, the following effects can be obtained.
(A) Since the curing composition can bind the fiber obtained by pulverizing paper pulp, waste paper, etc. through a binder, the water retention necessary for curing and the adhesion and retention on the surface of the concrete body Can be satisfied at the same time.
(B) Since each component is set in a specific range, it is possible to provide a curing composition that is excellent in adhesion at the time of spraying construction and the like and excellent in work efficiency and curing effect.
Here, if the binder and the fiber content are less than 1 part by weight and 15 parts by weight, respectively, the caking property and water retention are insufficient, and conversely, if they exceed 25 parts by weight and 80 parts by weight, the spraying workability deteriorates. This is not preferable. Further, although depending on the binder used, the type of fiber, and the like, it is not preferable that the added water is less than 200 parts by weight because the dispersibility of the fiber tends to deteriorate. Conversely, if the added water exceeds 800 parts by weight, the amount of water flowing out to the surrounding environment exceeding the amount of water that can be retained by the curing coating layer is not preferable. In particular, depending on the environmental temperature, the binder is 2.5 to 10 parts by weight, the fiber content is 20 to 60 parts by weight, the moisture is 250 to 600 parts by weight, there is no rebound loss or sagging, and the fiber This is preferable because of its excellent dispersibility of the minute.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
The concrete body curing method according to Embodiment 1 of the present invention will be described.
1 is an explanatory diagram of a concrete body curing method according to Embodiment 1. FIG. In addition, in order to avoid duplication of description, the curing method will be described using one side of the concrete body.
1 and 2, 10 is a concrete body before curing with the formwork removed, 11 is a surface of the concrete body, 11 a is a curing coating layer formed on the surface of the concrete body 10, and 12 is a surface 11 of the concrete body. Spray nozzles for spraying the curing composition, spray nozzles such as spray nozzles, 13 nozzles of spray machine 12, 14 trucks equipped with spray machine 12, 15 curing coating layer formed by spraying with spray machine 12 11a is a water supply tubular body having a large number of water passage holes arranged along the uppermost portion of the uppermost portion of 11a.
Curing composition consists of (1) natural fiber finely cut from old paper (Oyo fiber), (2) polyvinyl acetate resin (MUK Bond 2020L and Cricoat C-402) as binder, (3) Industrial It is obtained by mixing water. For example, surface area of concrete body 100m ² The amount used per unit is (1) 20 to 40 kg, (2) MUK bond 2020L: 2.5 to 3.8 kg + cricoat: 0.05 to 1.9 kg, and (3) 300 to 450 kg.
The MUK Bond 2020L is a binding agent manufactured by Maruhishi Oil Chemical Co., Ltd., and other binding agents include trade name: Kurikote C-402 (viscosity 34-74 mPa · s) etc. can be applied.
In addition, mixing of the said curing composition can be performed with a mortar mixer etc. using the water adjusted to predetermined temperature, for example, 15-25 degreeC.
Further, as the binder, a binder formed of a synthetic adhesive other than the above or a natural adhesive such as starch can be used. Moreover, the fiber part which consists of a sawdust, a cellulose fiber, a protein fiber, and the ground material of an inorganic fiber can also be used, and a synthetic adhesive and a natural adhesive can also be used in combination.
[0019]
As a test case, a concrete body 10 having a height of 3 to 10 m and a width of 5 to 20 m and having an anchor bolt 10 a and the like embedded therein was used.
The curing coating layer 11a is formed by spraying the curing composition and solidifying it by moving the nozzle 13 of the sprayer 12 along the surface 11 of the concrete body at a predetermined speed while maintaining a predetermined interval. did. At this time, by adjusting the spraying amount and moving speed according to the temperature and weather at the site, the curing composition sprayed on the surface 11 of the concrete body hangs more than specified and does not flow. It is desirable to set such an appropriate range (for example, a thickness of 3 to 6 mm).
[0020]
2 (a) is a front view of the surface of a concrete body on which a curing coating layer is formed, FIG. 2 (b) is a side sectional view thereof, and FIG. 2 (c) is a sectional view of a water supply tubular body. is there. In FIG.2 (c), 15a is the partition part extended in the length direction of the inside center of the water supply tubular body 15, 15b and 15c are the upper water flow part and the lower water flow part each divided by the partition part 15a up and down, respectively. , 15d are distribution holes formed at predetermined intervals in the partition portion 15a, and 15e is a water flow hole provided at a predetermined interval in the upper water flow portion 15c.
As shown in FIG. 2 (c), the water supply tubular body 15 is partitioned into an upper water flow portion 15b and a lower water flow portion 15c by a partition portion 15a extending in the longitudinal direction of the inner center of the tubular portion. The pressurized water supplied to the water portion 15c passes through the distribution hole 15d formed in the partition portion 15a, flows into the upper water passage portion 15b, and passes through the water passage holes 15e provided at predetermined intervals on the upper water passage portion. A small amount so as to wet the entire surface of the concrete body 10 is formed by being connected to a watering source (not shown) so that water is automatically sprinkled during the curing period.
[0021]
The concrete body 10 is maintained by watering the curing coating layer 11a in a wet state by spraying water from the water passage holes 15e of the water supply tubular body 15 disposed along the uppermost portion on the uppermost upper surface of the curing coating layer 11a. The curing was performed.
Thus, the concrete body 10 was cured by holding the concrete body 10, which is a young material on which the curing coating layer 11 a was formed, at a high temperature of 25 to 35 ° C. for about 14 days or more.
After curing, water was applied to the surface 11 of the concrete body 10 using a hose, and the curing coating layer 11a deposited on the surface was washed away and removed. As another method, after drying the curing coating layer 11a, the curing coating layer 11a may be sucked and collected using a vacuum cleaner or the like, and then washed with water.
The curing coating layer 11a is composed of a binder such as polyvinyl acetate resin and starch, cellulose fibers such as paper pulp and waste paper, and protein fibers. It is gentle and does not generate harmful components even when incinerated, so it has excellent environmental preservation.
Thus, according to the curing method of the first embodiment, there is no curing spots and the occurrence rate of defects due to curing can be remarkably reduced as compared with the conventional method using the curing sheet, and the compactness and durability of the concrete can be reduced. Can significantly improve the performance.
Moreover, since the curing coating layer 11a can be rapidly formed after removing the formwork at an early stage, the construction efficiency is improved and the construction cost is reduced. Moreover, automatic watering can be performed simply by preparing a water storage tank containing water for the amount of water sprayed or by attaching a regulating valve to the water supply, which is excellent in labor saving.
The water supply tubular body 15 is held by a temporary material such as a pipe support on the upper part when the concrete body 10 is a wall surface or the like, or on the upper or lower surface when the concrete body 10 is a floor slab or the like.
[0022]
Since the concrete body curing method of Embodiment 1 is configured as described above, it has the following effects.
(1) Since the curing composition containing moisture, binder and fiber is sprayed on the surface 11 of the concrete body, the anchor effect on the surface 11 of the concrete body even when a decorative plywood having a smooth surface is used as a formwork The curing coating layer with excellent water retention can be retained, and the curing efficiency can be effectively increased.
(2) The curing coating layer 11a can be easily formed simply by spraying the curing composition on the surface 11 of the concrete body, and is applied to the concrete body of a large-scale and complicated structure to perform continuous construction. It has excellent workability and workability.
(3) Since the curing composition to be sprayed has appropriate caking fluidity, the curing coating layer 11a can be formed on the wall or ceiling of the structure, and the occurrence of defects such as cracks due to evaporation of moisture is effective. Can be prevented.
(4) Since water droplets are always supplied to the curing coating layer 11a through the water supply tubular body 15 and maintained in a wet state, there is no shrinkage difference due to drying, and the occurrence of cracks and the like is effective. Can be prevented.
(5) Since it is only necessary to arrange the water supply tubular body 15 at a predetermined portion such as the upper part of the concrete body 10, the installation is easy, and the surface 11 of the concrete body can be maintained in a proper wet state with a small amount of water, Excellent economic efficiency.
(6) Moisture evaporated from the surface 11 of the concrete body is blocked by the curing coating layer 11a applied without flowing, and the concrete body 10 is maintained in a wet state for a long period of time. It can be cured until it is durable.
(7) Since the curing coating layer 11a and the surface 11 of the concrete body are uniformly sprayed and formed without generating a cavity or the like, a structure having no defect can be efficiently obtained.
(8) Since the content of the binder in the curing composition is adjusted to a specific range, rebound loss and poor adhesion at the time of spraying are suppressed, and workability at the time of construction can be improved.
(9) The viscosity and the like of the curing composition can be adjusted to a predetermined range, and a constant amount of the curing composition can be sprayed to the surface 11 of the concrete body at all times, and the curing coating layer 11a having a certain thickness can be formed. Construction management can be performed easily.
(10) Since the pressurized water supplied to the lower water flow portion 15c passes through the distribution hole 15d formed in the partition portion 15a and flows into the upper water flow portion 15b, the upper water flow portion that is pressure-equalized thereby Water can be discharged to the outside from the water passage hole 15e provided in 15b, and the curing coating layer 11a over a wide range can be efficiently maintained in a wet state.
(11) Since the water passage holes 15e are provided in the upper portion of the upper water passage portion 15b at a predetermined interval, the water can be retained without causing the binder to flow out from the curing coating layer, and the curing coating The layer can be maintained well.
(12) When removing the curing coating layer 11a after curing, the suction coating layer 11a is pressed against the suction port of a vacuum cleaner or the like, and directly removed by vacuum suction or sprayed with high-pressure water. It can be cleaned and removed, and has excellent removal workability.
(13) Natural binders such as starch and cellulose, which are harmless to the environment, can be applied to the binder and fiber content, and are less likely to be degraded by bacteria in the soil and contaminate the environment. Moreover, since these can be collected and recycled, they are excellent in environmental preservation and economy.
[0023]
(Embodiment 2)
A concrete body curing method according to Embodiment 2 of the present invention will be described.
FIG. 3 is an explanatory diagram of the concrete body curing method according to the second embodiment.
In FIG. 3, reference numeral 20 denotes concrete before curing from which a formwork (not shown) is removed, 21 is the surface of the concrete body, 21 a is concrete whose end is hooked or stuck to an anchor bolt 21 b or the like on the top of the concrete body 20. A net-like sheet disposed so as to cover the surface 21 of the body, 21c is a curing coating layer formed by adhering a caking composition containing moisture and a binder to the net-like sheet 21a, 22 is a surface 21 of the concrete body A sprayer such as a spray nozzle for spraying a caking composition containing water and a binder, 23 is a nozzle of the sprayer 22, and 24 is a truck on which the sprayer 22 and the tank 25 are mounted.
The curing coating layer 21c is provided with a water supply tubular body 15 similar to that of the first embodiment by using a temporary material or the like along the uppermost portion of the uppermost upper surface, and after the curing coating layer 21c is formed. Then, water is supplied to the water supply tubular body 15 at a predetermined water pressure, so that water in the form of mist droplets is sprayed from the water passage holes 15e or drops of water are dropped, and the curing coating layer 21c is in a wet state during the curing period. Arranged so as to be maintained.
The water supply tubular body 15 was attached via a temporary material provided on the concrete body 20 such as an anchor bolt 21b. When a flat hose or the like formed into a tape shape is arranged as a water supply tubular body, it may be fixed to the upper part of the concrete body 20 by an adhesive means using an adhesive or a binding means using a wire or string. Good. The water passage hole 15e is formed so as to penetrate the surface of the water supply tubular body 15, the diameter of the hole is set to 0.01 to 0.3 mm, and water can be supplied to the curing coating layer 21c with a specified water pressure such as tap water without excess or deficiency. To be supplied.
[0024]
The caking composition is obtained by mixing (1) a predetermined amount of moisture with (1) MUK bond 2020L containing caking agent and cricoat C-402. For example, surface area of concrete body 100m ² The amount used per unit is (1) 3 kg (MUK bond 2020L), 0.1 kg (cricoat), and (2) 200 kg, which can be mixed with a mortar mixer or the like.
[0025]
As the test case, a concrete body 20 having a height of 3 to 10 m and a width of 5 to 20 m and having an anchor bolt 21 b and the like embedded therein was used.
The net-like sheet 21a is a sheet-like body made of a nonwoven fabric or a woven fabric made of synthetic fibers such as polyester, nylon, and acrylic, cellulose fibers, and protein fibers. In the present embodiment, the trade name: Bennet made by Asahi Kasei Kogyo Co., Ltd. was used. The upper end portion of the mesh sheet 21 a is suspended by hanging on the anchor bolt 21 b or the like, and the mesh sheet surface is widened with a slack with respect to the surface 21 of the concrete body 20.
The material such as the nonwoven fabric or the woven fabric is reinforced with a metal mesh having a mesh interval of about 1 to 30 mm made of steel or stainless steel, and the workability when the mesh sheet is disposed on the surface 21 of the concrete body, You may make it improve the removal workability | operativity at the time of peeling after curing.
[0026]
In order to form the curing coating layer 21c including the mesh sheet 21a on the surface 21 of the concrete body, first, the nozzle 23 of the sprayer 22 is maintained at a predetermined speed along the surface 21 of the concrete body at a predetermined speed. It can be formed by moving, spraying the caking composition, attaching the reticulated sheet 21a to the surface 21 of the concrete body and attaching it. Thereby, the curing coating layer 21c having the mesh sheet 21a as the core material can be uniformly formed on the surface 21 of the concrete body with a predetermined thickness, for example, 3 to 10 mm.
[0027]
Alternatively, a curing coating layer can be formed by preliminarily attaching and solidifying a water-soluble binder to the mesh sheet, and spraying or spraying water on the mesh sheet. .
That is, the surface of the concrete body before curing is covered with a reticulated sheet containing a solidified binder, and water is sprayed on the reticulated sheet to soften the reticulated sheet to which the binder has adhered. A curing coating layer can be formed on the surface of the film, which makes construction extremely easy and reduces material loss.
[0028]
In this way, the concrete body 20 which is the young material on which the curing coating layer 21c is formed is sprayed with water from the water supply tubular body 15 at a high temperature of 25 to 35 ° C. for about 10 days, so that the concrete body 20 The concrete body 20 was cured while keeping the surface 21 in a wet state.
After performing this curing, the curing coating layer 21c was peeled off together with the mesh sheet 21a and removed.
[0029]
Since the concrete body curing method of the second embodiment is configured as described above, it has the following actions in addition to the actions of the first embodiment.
(1) Since the curing coating layer 21c including the mesh sheet 21a is formed on the surface 21 of the concrete body, the strength of the curing coating layer 21c fixed to the surface 21 of the concrete body is increased, and the surface 21 of the concrete body over a long period of time. Can be protected from drying and impact.
(2) When removing the curing coating layer 21c, since the mesh sheet 21a is contained as a core material, the entire curing coating layer 21c can be easily peeled off, and the workability in the removal work is excellent.
(3) Since the surface of the concrete body 20 can be kept in a wet state for a long period of time, high-quality concrete having excellent strength and durability can be obtained.
(4) When the net-like sheet 21a is reinforced with a metal net or the like, the curing coating layer 21c can be easily peeled off from the surface 21 of the concrete body after curing, and the workability is excellent.
(5) Since the net-like sheet 21a is arranged, the adhesiveness is better and the rebound loss can be reduced compared to the case where the curing composition as in the first embodiment is sprayed directly on the surface 21 of the concrete body.
(6) The net-like sheet becomes resistant to the caking composition flowing down, and the flowing speed can be delayed, and a curing coating layer having a uniform structure can be finally formed.
(7) When a binder is included in the mesh sheet in advance, the mesh sheet 21a is disposed on the surface 21 of the concrete body, and the curing coating layer 21c is applied to the surface 21 of the concrete body simply by spraying moisture on the sheet 21a. It is excellent in workability and economy.
(8) Moreover, since the curing coating layer 21c including the net-like sheet 21a formed by adhering to the surface 21 of the concrete body can be made uniform, variations in temperature and humidity can be suppressed, and the curing conditions can be maintained well.
[0030]
(Embodiment 3)
A concrete body curing method according to Embodiment 3 of the present invention will be described.
The concrete body curing method according to Embodiment 3 is a pre-curing concrete in which a mold is removed from a curing composition containing moisture, a binder such as polyvinyl acetate resin and starch, and fiber components such as paper pulp and waste paper. A curing coating layer having a predetermined thickness, for example, 3 to 6 mm, was formed by spraying on the surface of the body. Next, the curing coating layer was dried and solidified to form a heat insulating layer, and the surface of the concrete body was maintained in a heat insulating state.
[0031]
The curing coating layer is formed on the surface of the concrete body through a spraying means such as a spraying machine in the same manner as in the first or second embodiment.
Since this curing composition contains a binder and a fiber component, a structure excellent in heat insulation can be obtained by holding air in the gap between the fiber components such as paper pulp and waste paper fixed to each other by the binder. It could be formed on the curing coating layer. This effectively prevents heat dissipation from the surface of the concrete body and keeps the concrete surface under curing without freezing even in cold temperatures where the temperature is close to zero degrees. I found out I can get things.
[0032]
Since the concrete body curing method of the third embodiment is configured as described above, it has the following actions in addition to the actions of the first and second embodiments.
(1) A curing composition containing moisture, a binder, and fiber is sprayed onto the surface of the concrete body to form a curing coating layer, and the curing coating layer is dried and solidified to form a heat insulating layer, and the surface of the concrete body is formed. Since it is kept warm, even if the temperature at the construction site is low, near zero degrees, the heat-absorbing curing coating layer effectively suppresses the heat release of hydration heat accompanying the hardening of the concrete, and defects due to freezing. Can be prevented from occurring in concrete structures.
(2) Since the curing coating layer can be formed with the fiber fixed with the binder, it can be used as a heat insulating layer on the surface of the concrete body excellent in heat insulation.
(3) Since the curing coating layer is fixed with a binding agent, it can be easily removed by being wetted with water after drying, and has excellent workability during removal.
[0033]
【The invention's effect】
According to the concrete body curing method of claim 1, the following effects can be obtained.
(A) A curing coating layer can be easily formed just by spraying a curing composition on the surface of a concrete body, and can be applied to a concrete body with a large-scale and complicated structure to perform continuous construction. Excellent workability.
(B) The curing coating layer can be composed of fibers and binders that are not harmful to the environment, and after curing, the curing coating layer is sprayed with washing water or vacuum suction. It is possible to easily carry out the post-processing to remove the.
(C) Natural binders such as starch and cellulose, which are harmless to the environment, can be applied to the binder and fibers, and they are not decomposed by bacteria in the soil to pollute the environment. Excellent retention.
(D) Since there is a step of constantly maintaining the curing coating layer in a wet state by spraying water from the water passage holes, there is no difference in shrinkage due to drying of the concrete body, which is effective in generating cracks and the like. Can be prevented.
(E) Since the sprayed curing composition has appropriate caking properties and water retention, a curing coating layer can be easily and uniformly formed on the wall or ceiling of a vertically erected concrete body. Can do. The fiber is entangled with minute irregularities on the surface of the concrete body and has excellent retention. In addition, since the binder is a water-soluble polymer, it is compatible with the concrete body and penetrates into the fine pores, and is concentrated by the heat of the concrete body in the deep part of the pores, so that the fiber content can be held by the adhesive strength.
(F) Since the curing coating layer has water-retaining fibers, water that is sprayed from the water supply tubular body can be easily absorbed, and moisture can be concentrated in one place by the capillary tissue formed between the fibers. And can be dispersed over a wide range. As a result, the surface of the concrete body can be maintained in a wet state with a minimum amount of water, and can be cured until predetermined strength and durability necessary for the structure are provided.
(G) Since the curing coating layer is sprayed and applied to the surface of the concrete body without causing cavities and the like, a concrete body free from cracks on the surface having no variation in curing conditions and having no defects in strength can be obtained.
(H) Since the water-absorbing tubular body is flexible, it can be easily placed on the top of the concrete body, etc., and can be automatically supplied with water. Since the surface can be maintained in a proper wet state, it is excellent in economic efficiency.
[0034]
According to the concrete body curing method according to claim 2, the following effects can be obtained.
(A) A curing coating layer containing a net-like sheet is formed on the surface of the concrete body, the strength of the curing coating layer having water retention can be increased, and the surface of the concrete body can be protected from drying, impact, etc. over a long period of time. .
(B) Since a net-like sheet having fine irregularities and fluffs is arranged, the adhesion when spraying the caking composition is good, and the anchoring effect is good and the rebound loss is reduced, making it economical. Excellent.
(C) Since the net-like sheet becomes resistant to the caking composition flowing down the surface of the concrete body, the caking composition can be fixed in the meantime to form a curing coating layer having a uniform structure.
(D) Since moisture is supplied through the water supply tubular body and the curing coating layer can be maintained in a wet state with a minimum amount of moisture, it is excellent in stability maintenance and economics of curing conditions.
(E) The curing coating layer can be composed of a water-soluble starch-based binder that is less harmful to the environment, can be easily washed away after curing, and the curing coating layer is removed. Excellent environmental preservation.
(F) When removing the curing coating layer, since the net-like sheet is contained as a core material, the entire curing coating layer can be easily peeled off, and the workability is excellent.
(G) Placing a reticulated sheet on the surface of the concrete body, and spraying moisture on it, softens the reticulated sheet with a binder and adheres it to the surface of the concrete body to form a curing coating layer. Therefore, the construction can be performed very easily and the workability is excellent.
(H) Since the curing coating layer including the net-like sheet formed by adhering to the surface of the concrete body can be made uniform, variations in temperature and humidity are suppressed, and the curing conditions can be maintained satisfactorily.
(I) When removing the curing coating layer, the entire curing coating layer can be easily peeled off, and the workability is excellent.
(J) Since water droplets are constantly supplied to the curing coating layer and maintained in a wet state, there is no difference in shrinkage due to drying, and the occurrence of cracks and the like can be effectively prevented.
(K) Since it is only necessary to arrange the water supply tubular body on the upper part of the mesh sheet, the installation is easy, and the surface of the concrete body can be maintained in a proper wet state with a small amount of water, which is excellent in economy.
[0035]
According to the concrete body curing method according to claim 3, in addition to the effects of claim 1 or 2, the following effects can be obtained.
(A) Since the content of the binder in the curing composition is adjusted to a specific range, rebound loss and poor adhesion when spraying the curing composition onto the surface of the concrete body are suppressed, and work during construction Can be improved.
(B) Since the viscosity of the curing composition falls within a predetermined range, a constant amount of the curing composition can be sprayed to the surface of the concrete body at all times, and a curing coating layer having a certain thickness can be formed, and its construction management Can be done easily.
[0036]
According to the concrete body curing method according to claim 4, in addition to the effects of claim 2 or 3, the following effects can be obtained.
(A) Since the net-like sheet is made of a long-fiber nonwoven fabric such as natural fiber or water-absorbing polymer resin, the caking composition to be sprayed can be efficiently captured, and the rebound loss is reduced and the economy is excellent. .
(B) Capillary structure excellent in water absorption can be formed in the curing coating layer, and the moisture of the water droplets sprayed in a dotted manner is spread over a wide range to maintain the entire curing coating layer in a uniform wet state. And can be easily maintained.
(C) Since water retention is imparted to the curing coating layer, it is possible to minimize the amount of water spray necessary for maintaining the wet state, thereby suppressing the influence on the environment.
(D) By using a non-woven fabric having a fluffy surface, it is possible to improve the adhesion even to the surface of a concrete body having a smooth surface by using a decorative plywood for the formwork material of the concrete body.
[0037]
According to the concrete body curing method according to claim 5, in addition to the effect of any one of claims 2 to 4, the following effects can be obtained.
(A) Since the pressurized water supplied to the lower water flow portion passes through the distribution hole formed in the partition portion and flows into the upper water flow portion, the pressure water is provided at the upper part of the pressure-equalized upper water flow portion. Water can be uniformly discharged toward the outside from the water passage hole, and the curing coating layer over a wide range can be efficiently maintained in a wet state.
(B) Since the water passage holes are provided in the upper part of the upper water passage at predetermined intervals, the water can be retained without causing the binder to flow out from the curing coating layer with a small amount of water continuously discharged. The curing coating layer can be maintained well.
[0038]
According to the concrete body curing method of the sixth aspect, the following effects can be obtained.
(A) A curing composition containing moisture, a binder, and fibers is sprayed onto the surface of the concrete body to form a curing coating layer, and the curing coating layer is dried and solidified to form a heat insulation layer, and the surface of the concrete body is Since the insulation temperature is maintained, even if the temperature at the construction site drops below zero degrees, the heat-absorbing curing coating layer effectively suppresses heat dissipation from the hydration heat that accompanies concrete hardening, and defects due to freezing occur in the concrete structure. It can be prevented from occurring in objects.
(B) Since the curing coating layer can be formed from the fiber fixed with the binder, it can be used as a heat insulating layer on the surface of the concrete body excellent in heat insulation.
(C) Since the curing coating layer is fixed with a binder, it can be easily removed by being wetted with water after drying, and is excellent in workability during removal.
[0039]
According to the curing composition of Claim 7, the following effects are obtained.
(A) Since the curing composition can bind the fiber obtained by pulverizing paper pulp, waste paper, etc. through a binder, the water retention necessary for curing and the adhesion and retention on the surface of the concrete body Can be satisfied at the same time.
(B) Since each component is set in a specific range, it is possible to provide a curing composition that is excellent in adhesion at the time of spraying construction and the like and excellent in work efficiency and curing effect.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a concrete body curing method according to a first embodiment.
Fig. 2 (a) Front view of the surface of a concrete body on which a curing coating layer is formed
(B) Side sectional view
(C) Sectional view of a water supply tubular body
3 is an explanatory diagram of a concrete body curing method according to Embodiment 2. FIG.
[Explanation of symbols]
10 Concrete body
10a Anchor bolt
11 Concrete body surface
11a Curing layer
12 Spraying machine
13 nozzles
14 tracks
15 Tubular body for water supply
15a Partition
15b Upper water passage
15c Lower water passage
15d distribution hole
15e Water vent
20 Concrete body
21 Concrete body surface
21a Mesh sheet
21b Anchor bolt
21c Curing coating layer
22 Sprayer
23 nozzles
24 tracks
25 tanks

Claims (7)

Curing including moisture and binders formed with synthetic adhesives such as polyvinyl acetate and natural adhesives such as starch, pulp and waste paper , sawdust, cellulose fibers, protein fibers, and fibers made of inorganic fibers Spraying the composition onto the surface of the pre-curing concrete body from which the form has been removed to form a curing coating layer; and a number of passages disposed along the uppermost portion on the uppermost surface of the curing coating layer. A method for curing a concrete body, comprising: sprinkling water from a water supply tubular body having water holes to maintain the curing coating layer in a wet state. A step of covering the surface of the concrete body before curing with the formwork removed with a net-like sheet, and a binder formed with a natural adhesive such as moisture and synthetic adhesive such as polyvinyl acetate or starch on the net-like sheet A step of forming a curing coating layer containing the mesh sheet by spraying the caking composition, and water supply having a plurality of water holes arranged along the uppermost portion of the uppermost portion of the curing coating layer A method for curing a concrete body comprising: watering a tubular body for maintaining the curing coating layer in a wet state. Regimen concrete body according to claim 1 or 2, wherein the content of the binder in the curing coating layer is 10~ 100 g / m ^2. The method for curing a concrete body according to claim 2 or 3, wherein the mesh sheet is formed of a natural fiber such as cotton or a long-fiber nonwoven fabric made of a water-absorbing polymer resin. The water supply tubular body is partitioned into an upper water flow portion and a lower water flow portion by a partition portion extending in the longitudinal direction at the center of the inside thereof, and pressurized water supplied to the lower water flow portion is perforated in the partition portion. Any one of claims 2 to 4, wherein the water passes through the distribution hole and flows into the upper water flow portion, and is sprayed from the water flow holes provided at a predetermined interval above the upper water flow portion. The curing method for concrete bodies according to claim 1. Curing including moisture and binders formed with synthetic adhesives such as polyvinyl acetate and natural adhesives such as starch, pulp and waste paper , sawdust, cellulose fibers, protein fibers, and fibers made of inorganic fibers A step of spraying the composition on the surface of the concrete body before curing removed from the formwork to form a curing coating layer, and drying and solidifying the curing coating layer to form a heat insulating layer so that the surface of the concrete body is kept warm. And a step of maintaining the concrete body. And synthetic adhesives and starch binder formed a natural adhesive such as, paper pulp and waste paper, sawdust, cellulose fibers, protein fibers, curing the coating to the concrete body containing a fiber content comprising a pulverized product of the inorganic fibers, the A curing composition for forming a layer, wherein the binder is 1 to 25 parts by weight, the fiber content is 15 to 80 parts by weight, and the added water is 200 to 800 parts by weight. .

Images