JP7142869B1 - Inorganic material construction method - Google Patents

Abstract

An object of the present invention is to propose an inorganic material construction method that enables simple and early construction even if the joint surface is less than saturated. SOLUTION: The inorganic material construction method is a method of constructing an inorganic material in which a fiber-reinforced cement composite material is spliced onto an existing concrete member, and the pavement provided on the surface of the existing concrete member is cut to cut the existing concrete member. A cutting step S11 for exposing the joint surface of the concrete member, a watering step S12 for spraying water on the joint surface so that the joint surface is less than saturated, and a fiber reinforcement without using an adhesive on the sprinkling joint surface. and a placing step S13 of directly placing the cement composite material. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to a method of applying an inorganic material to an existing concrete member.

Ultra High Strength Fiber Reinforced Concrete (UFC) has a low water-to-binder ratio and contains fibers, so construction management is generally difficult. For this reason, ultra-high-strength fiber-reinforced concrete was generally used for factory-produced precast members. is being considered.

Patent Document 1 discloses a construction method in which an epoxy resin-based adhesive is applied to the surface of an existing concrete member, and then a fiber-reinforced cement composite material is placed on the upper surface of the adhesive. However, according to this construction method, when the adhesive is applied or sprayed onto the concrete surface, the concrete surface must be dry. cannot be applied until the surface of the concrete member is dry.
Therefore, conventionally, a construction method as described in Patent Document 2 has been proposed. In this construction method, the joint surface of an existing concrete member is saturated with water, and a fiber-reinforced cement composite material is directly placed.

JP 2015-129393 A Japanese Patent No. 6051497

In the existing method of saturating the pouring surface of concrete members with water, it is necessary to sprinkle water to prevent the pouring surface from drying out, especially in hot seasons. Moreover, when water is sprinkled, the joint surface must be saturated with water, and a large amount of water is required to saturate the joint surface of a large area with water. From such a point of view, further improvement has been demanded.

An object of the present invention is to propose an inorganic material construction method that enables simple and early construction regardless of the amount of water to be sprinkled, even if the joint surface is less than saturated.

The present invention for solving the above-mentioned problems is a method for applying an inorganic material for joining a fiber-reinforced cement composite material to an existing concrete member, wherein the pavement provided on the surface of the existing concrete member is cut and the existing A cutting step of exposing the joint surface of the concrete member, a watering step of spraying water on the joint surface so that the joint surface is less than saturated, and a fiber-reinforced cement composite without using an adhesive on the joint surface that has been sprayed with water. and a casting step of directly casting the material.

Further, the method for applying an inorganic material includes, after the cutting step and before the watering step, an unevenness forming step of forming an unevenness having a plurality of convex portions and concave portions on the joint surface. In the setting step, the fiber-reinforced cement composite material was directly placed on the joint surface on which irregularities were formed and water was sprinkled .

According to this inorganic material construction method, if the joint surface is less than saturated, the fiber-reinforced cement composite material adheres to the joint surface and maintains the adhesive strength regardless of the state of water spraying. be able to do so. This is because the moisture contained in the fiber-reinforced cement composite material is less likely to be absorbed by the existing concrete member, and the moisture contained in the fiber-reinforced cement composite material prevents the surface of the existing concrete member from being hydrated. The reaction is accelerated, resulting in a dense, high-strength cured body, and in turn, a cured body with excellent blocking properties against deterioration factors. In addition, according to the construction method of the inorganic material, it is possible to reliably secure the adhesive strength by forming unevenness on the joint surface that increases the contact area with the fiber reinforced cement composite material to be placed. Furthermore, if the spliced surface is less than saturated, there is no need to judge the moisture state, so it is possible to shorten the construction period and reduce the cost.

In addition, the "fiber reinforced cement composite material" includes, for example, so-called ultra-high strength fiber reinforced concrete ( UFC) or high-strength fiber-reinforced mortar may be used. In addition, the unevenness having a plurality of protrusions and recesses formed on the joint surface is formed by a part of coarse aggregate and fine aggregate in which the protrusions are raised from the cement paste and fine aggregate, and the recesses are raised coarse aggregates. Except aggregate and fine aggregate, it is formed by other coarse aggregate, fine aggregate and cement paste. Further, in the unevenness forming step, the unevenness may be formed by a water jet, and in this case, it is preferable to perform the water jet discharge pressure within a range of 70 MPa or more and 270 MPa or less.

In the placing process, the fiber reinforced cement composite material is poured multiple times from one end side to the other end side of the joint surface to cover the entire joint surface, and then the fiber reinforcement covering the entire joint surface. It is good also as curing a cement composite material. In the placing step, the fiber-reinforced cement composite material is poured into each partitioned area while partitioning the joint surface from one end side to the other end side of the joint surface, and after covering the entire joint surface, You may make it cure the whole joint surface at once.

According to the inorganic material construction method of the present invention, the moisture content or moisture content of the water sprayed on the joint surface may be less than the saturated state, and the fiber reinforced cement composite material can be easily and quickly applied to the existing concrete member. It can be spliced so as to maintain adhesive strength. In particular, by forming unevenness on the joint surface, the contact area with the fiber-reinforced cement composite material increases, regardless of the amount of water sprinkled, even when the water is less than saturated. can be improved more reliably.

It is a flowchart figure which shows the construction method of the inorganic material which concerns on embodiment of this invention. FIG. 4 is a diagram schematically showing the cutting process of the method of applying the same inorganic material, wherein (a) is an explanatory diagram schematically showing the cutting process, and (b) is a partial cross-section schematically showing the state of the cut portion. It is a diagram. It is explanatory drawing which shows typically a watering process by the construction method of the same inorganic material. It is explanatory drawing which shows typically the casting process of the construction method of the same inorganic material. FIG. 3 is a perspective view showing a mixer; FIG. 4 is a schematic enlarged view showing the state of the placing step of the method of applying the same inorganic material, and FIG. , (b) is a partial cross-sectional view partially showing a state in which the poured fiber-reinforced cement composite material is leveled, and (c) is a partial cross-sectional view showing a state in which the placed fiber-reinforced cement composite material is paved. . It is a flowchart figure which shows the construction method of the inorganic material which shows an application example. FIG. 4 is a diagram showing a step of forming unevenness in the method of applying the same inorganic material, wherein (a) is a perspective view schematically showing the step of unevenness, and (b) is a partial cross-sectional view schematically showing a state in which unevenness is formed. . FIG. 4 is an enlarged cross-sectional view schematically showing an enlarged joint surface on which unevenness is formed in the unevenness forming step of the construction method of the same inorganic material. FIG. 4 is a schematic enlarged view showing the state of the placing step of the method of applying the same inorganic material, and FIG. , (b) is a partial cross-sectional view partially showing a state in which the poured fiber-reinforced cement composite material is leveled, and (c) is a partial cross-sectional view showing a state in which the placed fiber-reinforced cement composite material is paved. . It is a flowchart figure which shows the construction method of the inorganic material which concerns on another form. It is a figure showing the unevenness formation process of the construction method of the same inorganic material according to another embodiment, (a) is a perspective view schematically showing the unevenness process, and (b) schematically shows the state in which the unevenness is formed. It is a partial cross-sectional view. (a), (b) is explanatory drawing which shows typically the casting process of the construction method of the inorganic material which shows an application example. FIG. 2 is an explanatory diagram schematically showing a portion of a specimen used in an example according to the present invention for measuring adhesive strength.

In the embodiment of the present invention, in the repair work of an existing concrete floor slab, the surface of the concrete slab is coated with a hardened fiber-reinforced cement composite material (inorganic material), thereby preventing water, air, A case of suppressing permeation of deterioration factors such as salt will be described.
As shown in FIG. 1, the inorganic material construction method of the present embodiment includes a cutting step S11, a watering step S12, and a placing step S13. After the placing step S13, a curing step S14 is performed.

Here, the fiber-reinforced cement composite material used in the present embodiment includes at least a material consisting of cement, limestone filler, and silica fume to which reinforcing fibers, fine aggregate, water reducing agent, shrinkage reducing agent, antifoaming agent, and water are added. Ultra-high-strength fiber-reinforced concrete produced by kneading shall be used. In this embodiment, J-THIFCOM (registered trademark) is used as such ultra-high-strength fiber-reinforced concrete. Materials to be added to the fiber-reinforced cement composite material are not limited to those mentioned above.

In addition to J-THIFCOM (registered trademark), fiber-reinforced cement composite materials include so-called ultra-high-strength fiber-reinforced concrete (UFC) such as Succem (registered trademark), Ductal (registered trademark), and Slimcrete (registered trademark). can be used.
In this embodiment, ultra-high-strength fiber reinforced concrete (UFC) is used as a repair material for repairing existing concrete floor slabs. The repair material has sufficient strength as a floor slab, and is However, the fiber-reinforced cement composite material is not limited as long as it has a denseness that can block degrading factors such as water and air and has a yield strength that does not cause damage such as cracks.

Ordinary Portland cement is used for cement. The cement is not limited to ordinary Portland cement. For example, if early strength development is desired, high early strength Portland cement or ultra high early strength Portland cement can be used. In this embodiment, cement is added in the range of 300 to 450 L, preferably in the range of 330 to 400 L, per 1 m ³ of the mixture (ultra-high strength fiber reinforced concrete 7). If the amount of cement added is less than 300 L per 1 m ³ of the mixture, it may not be possible to ensure sufficient blocking performance against deterioration factors. Moreover, if the amount exceeds 450 L per 1 m ³ of the mixture, there is a possibility that fluidity cannot be ensured.

Limestone powder having a density of about 2.7 to 3.0 g/cm ³ and a CaCo ₃ (calcium carbonate) content of 95% or more is used as the limestone filler. Limestone filler is added in the range of 100 to 200 L, preferably in the range of 120 to 180 L, per ^cubic meter of mixture. Limestone powder has a good shape and is effective in improving the fluidity of the cement paste. If the amount of limestone filler added is less than 100 L per 1 m ³ of the mixture, it may not be possible to ensure adequate fluidity during placement. Further, if the amount of limestone filler added exceeds 200 L per 1 m ³ of the mixture, there is a risk that sufficient blocking performance against deterioration factors cannot be ensured.

As the silica fume, vitreous silica spherical ultrafine particles having a diameter of about 0.1 to 0.2 μm are used. Silica fume contributes to improving the strength and durability of concrete, and is effective in improving concrete construction (during kneading) by controlling the low water-to-powder ratio. Silica fume is added in the range of 30 to 80 L, preferably in the range of 40 to 60 L, per ^cubic meter of mixture. If the amount of silica fume to be added is less than 30 L per 1 m ³ of the mixture, the viscosity and material separation resistance are lowered, and the desired fluidity cannot be secured. Further, if the amount of silica fume added exceeds 80 L per 1 m ³ of the mixture, the balance of the chemical composition and the particle size distribution of the mixture will be lost, and there is a risk that sufficient blocking performance against deterioration factors cannot be ensured.

Fibers having a diameter of 0.15 to 0.3 mm and a length of 6 to 25 mm are used as reinforcing fibers. The fibers in this case may be either metallic or organic fibers, or a combination thereof. Organic fibers include vinylon fibers, polypropylene fibers, and carbon fibers.
The reinforcing fibers are added in the range of 1 to 6% by volume of the mixture. If the volume ratio of the reinforcing fiber is less than 1%, the reinforcing effect of the fiber is reduced, and there is a possibility that sufficient blocking performance against deterioration factors cannot be obtained. On the other hand, if the volume ratio of the reinforcing fibers is more than 6%, the fluidity of the concrete may decrease and the reinforcing fibers may not be evenly distributed. The unit amount of the fiber is preferably 75 to 315 kg/m ³ , more preferably 150 to 240 kg/m ³ per 1 m ³ of the mixture as long as the strain hardening property is not deteriorated.

As the fine aggregate, metal fine aggregate (for example, iron powder) or silica sand having a particle size of 0.05 to 0.3 mm is used. The combination of reinforcing fibers and fine aggregate contributes to improving the dispersion of fibers during mixing and stabilizing the specific gravity of the entire material in the mixer to prevent the generation of fiber balls. The amount of fine aggregate mixed is preferably 75 to 315 kg/m ³ , more preferably 150 to 240 kg/m ³ per 1 m ³ of the mixture as long as the strain hardening property is not lowered. In the case of silica sand, the mixing amount is preferably 25 to 110 kg/m ³ , more preferably 50 to 85 kg/m ³ per 1 m ³ of the mixture.

As water reducing agents, lignin-based, naphthalenesulfonic acid-based, melanin-based, polycarboxylic acid-based, AE water reducing agents, high performance water reducing agents, and high performance AE water reducing agents can be used. The amount of water reducing agent to be blended is preferably 21 to 48 kg/m ³ , more preferably 25 to 40 kg/m ³ of the mixture, in consideration of fluidity, separation resistance, strength and density after hardening of the mortar. ^m3 .

As the shrinkage reducing agent, one containing a compound represented by the chemical formula R ₁ O(A ₁ O)mH as a main component is used. In the chemical formula, R ₁ is hydrogen or a linear or branched alkyl group having 1 to 6 carbon atoms. The amount of the shrinkage reducing agent to be added is 25 to 45 kg/m ³ of the mixture, more preferably 30 to 40 kg/m ³ in consideration of workability of the mortar, separation resistance, strength after curing and crack resistance. ^m3 .

Examples of antipacking agents include phosphate-based, silicone-based, polyalkylene glycol-based, and polyoxyalkylene-based agents. The anti-packing material is added in an amount of preferably 7 to 16 kg/m ³ and more preferably 8 to 12 kg/m ³ per 1 m ³ of the mixture.

The water/binder ratio is preferably from 10 to 20% by mass, more preferably from 13 to 19% by mass, in view of the fluidity and separation resistance of the mortar, and the strength and durability after curing. If the water/binder ratio is less than 10% by mass, kneading may not be possible. On the other hand, if the water/binder ratio exceeds 20% by mass, there is a risk that sufficient blocking performance against deterioration factors cannot be ensured.
To the mixture of this embodiment, an expanding agent/setting accelerator, setting retarder, thickening agent, synthetic resin powder, polymer emulsion, polymer dispersion, etc. may be added, if necessary.

Next, each step of the inorganic material application method will be specifically described as follows.
The cutting step S11 is a step of cutting the surface of the concrete floor slab (existing concrete member) 1, as shown in FIGS. 2(a) and 2(b).
A pavement 2 is laid on the surface of the concrete floor slab 1. - 特許庁In addition, although the pavement 2 of the present embodiment is configured by the surface layer 2a and the base layer 2b, the pavement configuration is not limited to this.

In the cutting step S11, the road surface milling machine RB is used to cut the pavement 2 portion. The road milling machine RB includes, for example, a cutting mechanism for cutting the road surface, a cutting piece delivery mechanism for sending the pavement cutting pieces cut by the cutting mechanism to a transport vehicle TR such as a truck, and a crawler or wheel traveling on the road. and a running mechanism. An existing road milling machine RB can be used.
In the cutting step S11, after most of the pavement 2 is cut by using the road milling machine RB, a part of the pavement 2 that has not been cut by the road milling machine RB is applied to a part of the surface of the concrete floor slab 1. etc. may remain. A part of such remaining pavement 2, waterproofing, tack coat, etc. are preferably removed by chipping or the like.

Following the cutting step S11, the watering step S12 is performed.
As shown in FIG. 3, the water spraying step S12 is a step of spraying water on the joint surface 11 that is cut and exposed. In this watering step S12, water is sprinkled on the joint surface 11 from the water pipe 32 via the pump car 31, for example. The amount of water sprinkled in the water sprinkling step S12 is, for example, such that the existing concrete floor slab 1 is less than saturated. It is not necessary to use a large amount of water by making the water less than saturated in the watering step S12. In other words, in the watering step S12, the amount that is less than the saturated state may be any of the amount that will result in a wet state, the amount that will result in a less than wet state, and the amount that will result in a surface dry state.

By sprinkling water on the joint surface 11, the connection between the joint surface 11 and the ultra-high-strength fiber-reinforced concrete 7 to be placed in the next step can be reliably performed. In other words, by spraying water on the existing concrete floor slab 1, it is possible to suppress the absorption of water in the concrete floor slab 1, and it is possible to sufficiently maintain the moisture contained in the ultra-high-strength fiber-reinforced concrete 7 when placed. Become.

Moreover, in the water spraying step S12, it is preferable that the joint surface 11 is evenly sprayed with water regardless of whether it is in a less than saturated state, a wet state, or a less than wet state. Also, as the moisture content of the splicing surface 11, the saturated state, wet state, and less than wet state are described, for example, in Construction Machine Construction Vol. 65 No. 8 The range indicated by the count value of 137 to 520 or less in the count value indicating the measurement result indicated by the measurement method described in "Development of Moisture Meter Suitable for Moisture Control of Concrete Floor Slab Surface" announced at August 2013. becomes.

When the above measurement results are indicated by count values, the absolute dry state is 10 to 55 counts, the dry state is 60 to 132 counts, the surface dry state is 137 to 230 counts, the wet state is 235 to 520 counts, and the watered state. (saturated state) is 521 to 744 counts (744 or more). Therefore, in this embodiment, when the watering state in the watering step S12 is indicated by a count value, the value is in the range of 137 to 520 counts.

The count value measured here is obtained by using an electric resistance moisture meter as described in the paper mentioned above. The electrical resistance moisture meter used here, as described in the above paper, is a measuring device that is not easily affected by the unevenness of the concrete surface to be measured, and quantitatively measures the moisture content of the concrete surface to be measured. can be grasped. As an example of the electric resistance moisture meter, "Road Bridge Floor Moisture Meter HI-100" manufactured by Kett Chemical Laboratory Co., Ltd. can be used. By the way, the water content in the high-frequency capacitive moisture meter is about 2.7% in the dry surface state and 10.4% or more in the saturated state (watery state). In the wet state, it is 4.7-10.4%.

After the watering step S13, the placing step S13 is performed as shown in FIGS. 4 to 6(a) to (c). In addition, in FIG. 4, in order to make the description easier to understand, a part of each configuration is deformed.
The ultra-high-strength fiber-reinforced concrete to be placed in the placing step S13 is preferably produced on-site according to the timing of placing. In this embodiment, the ultra-high-strength fiber-reinforced concrete 7 is manufactured using a mixer M (see FIG. 5) installed in the work yard of the construction site.
Although the type of mixer M is not limited, it is desirable to use one that has vertical and horizontal axis rotation mechanisms, a rated voltage of 200 to 400 V, and a rotation speed of 45 to 55 ppm/min. As shown in FIG. 5, the mixer M of this embodiment has one side wall blade B1, two floor blades B2, and four bar blades B3. The side wall blades B1, the floor blades B2, and the rod-like blades B3 rotate (revolve) around a vertical axis provided at the center of the mixer M. Further, the four rod-shaped blades B3 rotate (rotate) around a vertical axis provided at the center of the rod-shaped blades B3.

Ultra-high-strength fiber-reinforced concrete is first kneaded for 2 minutes (empty kneading), excluding water, a liquid admixture such as a water reducing agent, and reinforcing fibers. Next, water and a liquid admixture are added and kneaded for 5 to 20 minutes (main kneading). Subsequently, reinforcing fibers are added and kneaded for 2 minutes to produce ultra-high-strength fiber-reinforced concrete. In addition, the method for manufacturing ultra-high strength fiber reinforced concrete (procedure is not limited to this.

The placing step S13 is a step of placing the ultra-high-strength fiber-reinforced concrete 7 on the joint surface 11, as shown in FIGS. 4 and 6(a) to (c).
In the placing step S13, the placing work is carried out regardless of the state of the moisture content, particularly in a state where the splicing surface 11 is sprinkled with water less than the saturated state. Therefore, the placing step S13 is directly performed on the joint surface 11 after watering in a less than saturated state.
The ultra-high-strength fiber-reinforced concrete 7 is cast from one end side of the joint surface 11 toward the other end side. In this embodiment, the ultra-high-strength fiber-reinforced concrete 7 produced by a mixer is transported to the placement site by a construction transport machine S such as a wheel-type tractor shovel, and then poured into one end side of the joint surface (Fig. 4, See FIG. 6(a)).

When the ultra-high-strength fiber-reinforced concrete 7 is poured into one end side of the joint surface 11 , the ultra-high-strength fiber-reinforced concrete 7 flows along the joint surface 11 so as to spread. At this time, the ultra-high-strength fiber-reinforced concrete 7 is poured into the joint surface 11 so that a portion of the joint surface 11 is higher than the placement height. Then, it is flattened to the height set by the finisher F or the like (see FIG. 6(b)). In the placing step S13, the ultra-high-strength fiber-reinforced concrete 7 is conveyed from one end side to the other end side of the joint surface 11 by the construction conveying machine S and poured, and the finisher F is used to level the concrete. In the placing step S<b>13 , the ultra-high-strength fiber-reinforced concrete 7 is placed over the entire joint surface 11 by performing such work. It should be noted that, here, the description has been given assuming that the finisher F is used to cast the ultra-high-strength fiber-reinforced concrete 7, but since the ultra-high-strength fiber-reinforced concrete 7 has fluidity and self-filling properties, By pouring it into the spliced surface 11, it may be placed so that it is evenly spread naturally.

The curing step S14 is a step of curing the ultra-high-strength fiber-reinforced concrete 7 placed on the concrete floor slab 1 .
Curing of the ultra-high-strength fiber-reinforced concrete 7 is performed by so-called normal curing. In addition, in the curing step S14, the surface may be protected by covering it with a sheet depending on the weather, the temperature of the outside air, or the like.
After performing the curing step S14, as shown in FIG. Work to install the pavement 2 such as.

According to the inorganic material construction method of the present embodiment, since water is sprayed on the joint surface 11 at a level below the saturated state, the amount of water sprayed can be small, and the joint surface can be superimposed without using an adhesive. By directly placing the high-strength fiber-reinforced concrete 7, it is possible to secure the bonding strength with the existing concrete floor slab 1 serving as a reference. Since the existing concrete floor slab 1 does not absorb more water than necessary in the ultra-high-strength fiber-reinforced concrete, the adhesive strength of the ultra-high-strength fiber-reinforced concrete can be ensured. Therefore, the ultra-high-strength fiber-reinforced concrete 7 accelerates the hydration reaction and becomes a dense, high-strength hardened body with an air permeability coefficient of 0.001×10 ⁻¹⁶ m ² or less. In addition, since the ultra-high-strength fiber-reinforced concrete 7 forms a dense hardened body, it is not necessary to install a waterproof material, a water-impermeable material, or the like on the surface.

In addition, the ultra-high-strength fiber-reinforced concrete 7 is prevented from cracking due to the cross-linking effect of the reinforcing fibers, and the hardened body has a high density and high strength. Therefore, the hardened body of the ultra-high-strength fiber-reinforced concrete 7 has a chloride ion penetration depth of 0 or less according to the JIS A 1171-2000 test method, and a neutralization depth according to the JIS A 1171-2000 test method. is 0 or less, and so-called salt damage can be suppressed.

In addition, since no adhesive is used, the labor and time required for drying the joint surface 11 can be omitted, so compared to the conventional construction method using an adhesive or the conventional construction method of sprinkling water in a saturated state. It is possible to shorten the construction period and reduce the cost. In addition, construction can be performed continuously from the watering step S12 to the placing step S13, so that the construction period can be shortened.

Since the ultra-high-strength fiber-reinforced concrete 7 is used as the repair material, the strength of the hardened body is higher than that of the conventional repair material, and the thickness can be reduced. Therefore, it is possible to reduce the weight of superstructures such as bridges, and in turn improve the earthquake resistance.
The embodiments according to the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and each of the above-described constituent elements can be modified as appropriate without departing from the scope of the present invention.

In the above-described embodiment, a case has been described in which the super-high-strength fiber-reinforced concrete 7 is poured after cutting a part of the existing structure (cutting process), but the cutting process may be performed as necessary. That is, for example, when pouring over a pre-placed concrete member (new structure), the joint surface may be sprinkled with less than saturated water before pouring the new fiber-reinforced cementitious composite material. The inorganic material construction method of the present invention may also be employed when thickening concrete is placed directly on the surface of an existing concrete member.

In the case of employing the inorganic material construction method of the present invention for repair work, the structure to be repaired is not limited to floor slabs. For example, when repairing a bridge pier, this inorganic material construction method may be adopted. When repairing a pier, repair is not limited to the upper surface of the pier, and repair of the side surface or the like is also possible. In addition, since it has been confirmed that the ultra-high-strength fiber-reinforced concrete 7 of this embodiment is excellent in self-filling properties, even when placing the side or bottom surface of an existing concrete member, It can be made to adhere|attach to a joint surface by filling in.

The fiber-reinforced cement composite material used in the inorganic material construction method according to the present invention is not limited to ultra-high-strength fiber-reinforced concrete. For example, fiber reinforced mortar may be used as a fiber reinforced cementitious composite.
Also, the formulation of the fiber-reinforced cement composite material is not limited to the formulation shown in the above embodiment.

Next, another embodiment of the inorganic material according to the present invention will be described with reference to FIGS. 7 to 10. FIG. In this embodiment of the inorganic material, the unevenness forming step S11A is performed after the cutting step S11 and before the watering step S12. In addition, the same reference numerals are given to the steps already explained, and the explanation thereof will be omitted as appropriate.
In this embodiment, in the cutting step S11, the pavement 2 is cut and removed by the road milling machine RB to expose the surface of the concrete floor slab 1, and then the unevenness 14 is formed on the joint surface in the unevenness forming step S11A.
The unevenness forming step S11A is a step of forming unevenness having a plurality of convex portions and concave portions on the exposed joint surface. In this unevenness forming step S11A, for example, as shown in FIG. be able to. After removing the asphalt, waterproofing, tack coat, etc. remaining on the surface of the existing concrete floor slab 1, all the weak portions of the existing concrete are removed in the unevenness forming step S11A. For this purpose, the chipping machine 3 grinds and cleans the surface using a water jet (cleans the surface while jetting water and chipping off the surface), so that the hammering machine 3 has unevennesses 14 having a plurality of convex portions 12 and concave portions 13 . A joint surface 11 is formed.

Here, as an example, the surface of the concrete floor slab 1 is ground with a water jet, and as shown in FIGS. 14 are formed. It should be noted that the unevenness forming means of the concrete floor slab 1 is not limited to the water jet. The work of forming unevenness by the chipping machine 3 is performed by spraying high-pressure water pressure-fed from a pump car 31 through a water pipe 32 toward the concrete floor 1 from a nozzle. At this time, by moving the chipping machine 3 at any time, high-pressure water is jetted to a predetermined range to form an unevenness 14 having a plurality of convex portions 12 and concave portions 13 on the splicing surface 11 .

Here, in the unevenness forming step S11A, as shown in FIG. 9, the formed protrusions 12 are formed by the coarse aggregates 22 and fine aggregates 23 used in the existing concrete floor slab 1 protruding from the cement paste. It depends on the part formed by the cement paste 21 and the part formed by the cement paste 21 protruding more than the other cement pastes 21 .
More specifically, the projections 12 are formed by protruding the coarse aggregates 22 and the fine aggregates 23 of the existing concrete floor slab 1 directly exposed from the cement paste 21 . In addition, the convex portion 12 is raised from the cement paste 21 in a state in which a part or the entire front portion of the coarse aggregate 22 and the fine aggregate 23 of the existing concrete floor slab 1 is covered with the cement paste 21. It is formed. Furthermore, the convex portion 12 is formed by grinding a part of the cement paste 21 of the existing concrete floor slab and protruding from the remaining cement paste 21 .
The concave portion 13 is formed by excluding the cement paste 21, the coarse aggregate 22 and the fine aggregate 23 in the protruding portion, the surface of the cement paste 21 other than that, and the surface of the coarse aggregate 22 exposed at the bottom surface which is substantially the same as the cement paste 21. and the surface of the fine aggregate 23 .

It is preferable that the unevenness 14 has an average height between the top of the protrusion 12 and the bottom of the recess 13 in the range of 1 mm to 15 mm. That is, the plurality of convex portions 12 and concave portions 13 are composed of the top portions of the convex portions 12 made of the coarse aggregate 22 and the fine aggregate 23 used in existing concrete, and the coarse aggregate 22 and the fine aggregate other than the convex portions 12. It is desirable that the average height of the bottom of the concave portion 13 by 23 and cement paste 21 is 1 mm or more and 15 mm or less. If the average height from the bottom of the concave portion 13 to the top of the convex portion 12 is less than 1 mm, it may be difficult to maintain the adhesive strength between the ultra-high-strength fiber-reinforced concrete 7 to be placed and the existing concrete joint surface 11. There is In addition, when the average height exceeds 15 mm, a configuration may occur in which the coarse aggregate 22 or the fine aggregate 23 is arranged on the cement paste 21 that is slightly raised with a small contact area. , there is a possibility that a weak portion is generated in the joint surface 11 .
Therefore, the lower limit of the average height is 1 mm or more, preferably 2 mm or more, and more preferably 3 mm or more. Moreover, the upper limit of the average height may be 15 mm or less.

The average height of the tops of the projections 12 and the bottoms of the recesses 13 on the splicing surface 11 is the average of the values obtained by measuring the heights of a predetermined number of regions spaced apart at equal intervals on the splicing surface 11. . For example, when the joint surface 11 is 4m×25m and 100m ² , a measurement area of 1m×1m and 1m ² surrounded by a frame is provided at three equidistant points in 25m in the length direction. Then, in the measurement area, measurement is performed by performing "measurement of macro texture depth of pavement surface by volume method" specified in Annex F of JIS D8301, which is an analysis method for road surface roughness. The measurement method specified here is called the sandpatch method. In this method, a large number of fine glass beads or sand are scattered on the road surface. Glass beads or sand are spread over the measurement area surrounded by the frame so as to fill the recesses of the road surface. The diameter and volume of the group of glass beads or sand spread over the measurement area are measured, and the height of the irregularities on the measurement surface is measured based on these measured values. Therefore, the average value of the measured values measured in a predetermined number of measurement regions can be used as the average height between the top of the convex portion 12 and the bottom portion of the concave portion 13 . Here, an area of 3/100 of the splicing surface 11 is measured as a measurement area, and the average height between the top of the convex portion 12 and the bottom of the concave portion 13 is obtained.

Furthermore, the discharge pressure of the water jet used in the chipping machine 3 is preferably in the range of, for example, 70 MPa or more and 270 MPa or less. If the ejection pressure is less than 70 MPa, it may be difficult to form the desired irregularities 14, and it may take a considerable amount of time. Further, if the discharge pressure exceeds 270 MPa, there is a high possibility that the surface of the concrete floor slab 1 will be excessively ground. Therefore, the lower limit of the discharge pressure of the water jet is 70 MPa or higher, preferably 90 MPa or higher, and more preferably 100 MPa or higher. The upper limit of the water jet discharge pressure is 270 MPa or less, preferably 260 MPa or less, and more preferably 250 MPa or less.

The cuttings (scrap) of the pavement 2 or the concrete floor slab 1 and wastewater generated in the unevenness forming step S11A are removed by suction (see FIG. 8(a)). In this embodiment, debris and waste water are collected in the tank of the vacuum vehicle 4 by sucking from the tip of the vacuum pipe 41 extending from the vacuum vehicle 4 .
The surface of the cutting surface (the splicing surface 11) may be cleaned as necessary along with the collection of debris. In addition, the debris may be collected and removed by an operator using a tool such as a broom.

After the unevenness forming step S11A is performed, the sprinkling step S12 is performed on the joint surface 11 having unevenness. This watering step S12 is performed as already explained. Note that when a water jet is used in the unevenness forming step S11A, the same effect as the unevenness forming step S11A and the water sprinkling step S12 are performed. S13 may be performed. Incidentally, when performing the placing step S13, the moisture content or moisture content of the joint surface 11 having the unevenness 14 may be measured (measuring step), and when it is absolutely dry, the watering step S12 may be performed. good.
In the placing step S13, the fiber-reinforced cement composite material is directly placed on the joint surface 11 on which the irregularities 14 are formed without using an adhesive. In the placing step S13, as shown in FIG. 10(a), the ultra-high-strength fiber-reinforced concrete 7 is placed on the joint surface 11 having the unevenness 14 from one end side to the other end side of the joint surface 11. . In this embodiment, the ultra-high-strength fiber-reinforced concrete 7 produced by a mixer is transported to the placement site by a construction transport machine S such as a wheel-type tractor shovel, and then poured into one end side of the joint surface (see FIG. 4). ).

When the ultra-high-strength fiber-reinforced concrete 7 is poured into one end side of the joint surface 11 , the ultra-high-strength fiber-reinforced concrete 7 flows along the joint surface 11 so as to spread. The ultra-high-strength fiber-reinforced concrete 7 is partially poured into the joint surface 11 so as to be higher than the height to be placed, and is evenly distributed to the height set by the finisher F or the like. (See FIG. 10(b)). In the placing step S13, the ultra-high-strength fiber-reinforced concrete 7 is conveyed from one end side to the other end side of the joint surface 11 by the construction conveying machine S, and then poured in, and then leveled by the finisher F, which is repeated. is done in
A curing step S14 is performed after the placing step S13. The curing step S14 is performed in the same manner as the steps already described. Further, after the curing step S14, the new pavement 2 is placed on the repaired ultra-high-strength fiber-reinforced concrete 7 via an adhesive (see FIG. 10(c)).

According to the inorganic material construction method of the present embodiment, the ultra-high strength fiber reinforced concrete 7 is placed through the unevenness 14 provided on the joint surface 11 and adhered to the existing concrete floor slab 1 serving as a reference. Strength can be secured. This is because the contact area is increased by the unevenness 14 of the joint surface 11, so that the bonding strength of the ultra-high-strength fiber-reinforced concrete can be ensured. Therefore, the ultra-high-strength fiber-reinforced concrete 7 accelerates the hydration reaction and becomes a dense, high-strength hardened body with an air permeability coefficient of 0.001×10 ⁻¹⁶ m ² or less. In addition, since the ultra-high-strength fiber-reinforced concrete 7 forms a dense hardened body, it is not necessary to install a waterproof material, a water-impermeable material, or the like on the surface.

In addition, the ultra-high-strength fiber-reinforced concrete 7 is prevented from cracking due to the cross-linking effect of the reinforcing fibers, and the hardened body has a high density and high strength. Therefore, the hardened body of the ultra-high-strength fiber-reinforced concrete 7 has a chloride ion penetration depth of 0 or less according to the JIS A 1171-2000 test method, and a neutralization depth according to the JIS A 1171-2000 test method. is 0 or less, and so-called salt damage can be suppressed.

In addition, it is possible to shorten the construction period and reduce the cost compared to the conventional construction method using an adhesive and the conventional construction method of sprinkling water in a saturated state. In addition, since the step S11A for forming the unevenness can be continuously performed from the step S13 for placing, the construction period can be shortened.
As the repair material, the ultra-high-strength fiber-reinforced concrete 7 is used for the joint surface having unevenness, so the strength of the hardened body is higher than that of the conventional repair material, and the thickness can be reduced. Therefore, it is possible to reduce the weight of superstructures such as bridges, and in turn improve the earthquake resistance.

In the above-described embodiment, a case has been described in which the super-high-strength fiber-reinforced concrete 7 is poured after cutting a part of the existing structure (cutting process), but the cutting process may be performed as necessary. That is, for example, when joining to a previously placed concrete member (newly constructed structure), the new fiber-reinforced cement composite material may be placed in a state in which the joint surface (joint surface) is uneven. good. The inorganic material construction method of the present invention may also be employed when thickening concrete is directly placed on the surface of an existing concrete member without using an adhesive.

In the case of adopting the construction method of the inorganic material of the present invention as a repair work, the structure to be repaired is a floor slab, for example, when repairing a bridge pier, even if this construction method of an inorganic material is adopted. good. When repairing a pier, repair is not limited to the upper surface of the pier, and repair of the side surface or the like is also possible. In addition, since it has been confirmed that the ultra-high-strength fiber-reinforced concrete 7 of this embodiment is excellent in self-filling properties, even when placing the side or bottom surface of an existing concrete member, It can be made to adhere|attach to a joint surface by filling in.

The fiber-reinforced cement composite material used in the inorganic material construction method of the present invention is not limited to ultra-high-strength fiber-reinforced concrete. For example, fiber reinforced mortar may be used as a fiber reinforced cementitious composite. Also, the formulation of the fiber-reinforced cement composite material is not limited to the formulation shown in the above embodiment.

Next, another embodiment of the inorganic material application method will be described with reference to FIGS.
In this inorganic material construction method, the surface of the existing concrete member is cut to expose the joint surface, and a concavo-convex joint surface forming step ( Concavo-convex forming step) S11AB, water sprinkling step S12 in which water is sprinkled on the joint surface 11 on which the concavo-convex pattern is formed in a state below saturation, and pouring a fiber-reinforced cement composite material directly on the joint surface on which the concavo-convex pattern is formed. and a setting step S13.
In the uneven joint surface forming step S11AB, the surface of the pavement 2 and the existing concrete floor slab 1 is cut to expose the joint surface 11 by cutting the surface of the concrete floor slab 1, and the exposed joint surface 11 is provided with a plurality of 12 and 13 are formed. In this step S11AB, the surfaces of the pavement 2 and the concrete floor slab 1 are cut by a road surface milling machine RB to expose the joint surface 11 in a state in which unevenness 14 is formed on the joint surface 11 .

In the concavo-convex joint surface forming step S11AB, for example, preliminary grinding work is performed on a part of the road to be repaired in advance, and the thickness of the pavement 2 is confirmed and the thickness of the existing concrete floor slab 1 to be cut is measured by, for example, the road surface milling machine RB. set to Then, the setting of the thickness of the pavement 2 confirmed by the preliminary grinding work and the setting of the cutting thickness of the existing concrete floor slab 1 are performed in the road surface milling machine RB. By grinding the surface of the pavement 2 to the thickness for grinding the surface of the existing concrete floor 1 with a road surface milling machine RB, a predetermined thickness of the pavement 2 and the existing concrete floor slab 1 is cut and spliced. Surface 11 is exposed. The joint surface 11 is ground by a road surface milling machine RB to form an unevenness 14 having a plurality of convex portions 12 and concave portions 13 . The unevenness 14 includes a plurality of protrusions 12 and recesses 13 . It should be noted that the unevenness 14 includes a plurality of protrusions 12 and recesses 13, and since the configuration is the same as that already described, the description thereof is omitted here.

After performing the uneven joint surface forming step S11AB, it is preferable to perform a removing operation for removing fragments (scrap) of the ground material scattered during grinding (see FIG. 8A). A water jet may be used in the removal work (removal work process). When using a water jet, it is preferable to discharge water with a discharge pressure within a predetermined range, as already explained. In addition, in the removal work, by using a water jet with the chipping machine 3, the unevenness 14 formed on the joint surface 11 with the road milling machine RB is adjusted, and if a soft part remains, the soft part is removed. parts can be deleted. In the removing work, it is preferable to suck and remove the water and debris discharged by the vacuum wheel 4 while using the chipping machine 3 .

After the concavo-convex joint surface forming step S11AB, or the concavo-convex joint surface forming step S11AB and the removing process, the water sprinkling step S12 and the placing step S13 are performed. The water sprinkling step S12 is a step of sprinkling water on the joint surface 11 having the unevenness 14 so that the water is less than saturated. The placing step S13 is a step of placing the ultra-high-strength fiber-reinforced concrete 7 on the joint surface 11 on which the irregularities 14 are formed. Since the watering step S12 and the placing step S13 are the same as the steps already explained, the explanation is omitted here. After the placing step S13 is performed, the curing step S14 is performed. Since this curing step S14 is also the same as the step already explained, the explanation is omitted here. After the curing process is finished, new pavement 2 is installed on top of the repaired ultra-high strength fiber reinforced concrete 7 .

In the above, the construction method of the inorganic material, the construction method of the inorganic material of other forms, and the construction method of the inorganic material showing the application examples have been described. , the formwork 5 may be used to perform the placing step S13. For example, the formwork 5 is installed around the joint surface 11 . At this time, it is desirable to perform filling treatment so as not to form a gap between the contact surfaces of the formwork 5 and the concrete floor slab 1 . In addition, the material used for the formwork 5 is not limited, and for example, a wooden board may be used. Moreover, the range in which the formwork 5 is installed is not limited, and may be set as appropriate. For example, it may be set according to the capacity of the device for manufacturing the repair material to be placed in the placing process (the amount of repair material that can be manufactured).

Next, in the construction method that does not perform the unevenness forming step S11A, water is sprinkled in the formwork 5 in the water sprinkling step S12, and then the placing step S13 of placing the ultra-high strength fiber reinforced concrete 7 is performed. In the construction method already explained (see FIG. 4), the super-high-strength fiber-reinforced concrete 7 produced by a mixer is transported to the placement location by a construction transport machine S such as a wheel-type tractor shovel, and then placed in the formwork 5. Pour in (see FIG. 13(a)).
When the ultra-high-strength fiber-reinforced concrete 7 is poured into the formwork 5 , the ultra-high-strength fiber-reinforced concrete 7 flows within the formwork 5 . Since the ultra-high-strength fiber-reinforced concrete 7 has fluidity and self-filling properties, it is evenly spread in the formwork 5 by pouring it into the formwork 5 .

When the ultra-high-strength fiber-reinforced concrete evenly spread in the formwork 5 has reached a certain degree of retention of its shape, the formwork 5 is moved and as shown in FIG. Formwork 5 is arranged so as to be continuous with placed ultra-high strength fiber reinforced concrete 7 . Then, new ultra-high-strength fiber-reinforced concrete 7 is poured into the formwork 5 so as to be continuous with the ultra-high-strength fiber-reinforced concrete 7 placed previously. The ultra-high strength fiber reinforced concrete 7 may be placed on all the joint surfaces 11 by repeating the placing step using such a formwork 5 . The curing step S14 is preferably performed collectively after placing the ultra-high-strength fiber-reinforced concrete 7 on all the joint surfaces 11 .

In addition, in the construction method in which the unevenness forming step S11A is performed, the unevenness forming step S11A is performed after the cutting step S11 and before placing the formwork 5, the formwork 5 is installed, water is sprinkled inside the formwork 5, and then the water is sprayed. The setting step S13 is performed.

Next, regarding the construction method of the inorganic material, the results of testing the adhesive strength between the existing concrete floor slab and the ultra-high-strength fiber-reinforced concrete using ultra-high-strength fiber-reinforced concrete will be described as an example. It goes without saying that the present invention is not limited to the following examples. First, the test conditions are explained below.
[A1] A plain concrete slab of 300×300×60 mm JIS A5371 Appendix B is prepared.
[A2] Water is sprayed on the prepared ordinary concrete flat plate with a water jet discharge force of 240 MPa, and the uneven surface corresponding to the joint surface is formed by applying unevenness treatment so that the average height of the top of the protrusion and the bottom of the recess is It was formed to be 3 mm. In addition, an ordinary concrete flat plate (corresponding to the specimen (7) in Table 1) was prepared in which the joint surface was flattened so that no unevenness was formed.

[A3] The surface moisture content (surface moisture content) of the uneven surface was defined as four parameters ranging from a wet state to a surface dry state. The value of the surface moisture content differs depending on the spliced surface of the formed specimen (specimens (1) to (4) are uneven surfaces, and specimen (5) is a flat surface to be tested). 10 points in the region were measured, and the average value of the measured values is shown.
[A4] The surface moisture content (surface moisture content) of the joint surface was measured using an electric resistance moisture meter (road bridge deck moisture meter HI-100).
[A5] Ultra-high-strength fiber-reinforced concrete (J-THIFCOM: (registered trademark)) was directly placed on the uneven surface to a thickness of 20 mm.
[A6] Specimens (1) to (5) were formed by curing in a temperature-controlled room for 28 days after casting. The specimens (1) to (5) thus formed were subjected to an adhesion strength test at a material age of 7 days.

[A7] For the specimens (1) to (5) thus formed, an adhesion strength test was conducted in accordance with the Japan Society of Civil Engineers standard JSCE-K561 (jigs of φ5 cm). In the adhesion strength test, a metal jig was attached to the upper surface of the core-shaped portion via an epoxy resin adhesive using a jig of φ5 cm, and the adhesion strength was measured by pulling it up with a predetermined load. did. In addition, the adhesion strength test was conducted at 5 points/sheet of one test piece, and the average value was taken as the adhesion strength of each test piece. As shown in FIG. 14, in the plan view of the test piece, the adhesive strength was tested at the test positions TS at a total of 5 points, ie, the center and four points at the same distance from the center toward the four corners. As long as it is within the surface of the test piece, any position of the test piece may be used, and the average value of the five test positions TS may be used as the measurement value of the adhesion strength.
[A8] As a result of the adhesion test, good values were obtained regardless of the surface moisture content. The results of the adhesion test will be described later.

In Tables 1 to 3, the failure modes are as follows: A: destruction of base material, B: destruction of base material (including some interfaces), C: destruction from adhesive, D: super high strength fiber reinforced concrete surface layer Destruction (peeling). In addition, AB as a fracture mode indicates a fractured state in which the proportion of the interface is smaller than that of B including a part of the interface of B.
The results of the adhesion strength test are shown in Tables 1-3. Although Tables 1 to 3 are shown separately, the tables are separated for ease of viewing due to space limitations, and no particular technical distinction is made.

In Tables 1 to 3, the water content on the concrete surface of specimens (1) to (5) was measured using a road bridge deck moisture meter HI-100, and the value of the high-frequency capacity moisture meter (% of the moisture content) value) and the value of the electric resistance moisture meter (value indicated by count value). That is, the type (1) in the table is wet and has a moisture content of 10.4% or more: the count value is in the range of 235-520. Type (2) in the table has a water content of 5.0%: 250 in count value. Type (3) in the table has a water content of 4.0%: 200 in count value. Type (4) in the table has a water content of 3.1% and a count value of 155. Type (5) in the table had the same water content as (1).

As shown in Tables 1 and 2, in the specimens (1) to (4) in which the surface moisture content (surface moisture content) of the uneven surface is four parameters from the wet state to the surface dry state, the adhesive strength is 3.5. From 07 to 3.45 (N/mm ² ), it can be seen that a sufficient adhesive strength is ensured. In addition, as shown in Table 3, even in the specimen (5) in which the joint surface on which the ultra-high-strength fiber-reinforced concrete is placed has no unevenness, the average has an adhesive strength value of 1.99. As can be seen from the results of this example, when the sprinkling state of the spliced surface of the test piece is less than the saturated state due to the unevenness formed on the spliced surface of the test piece, the wet state or the surface dry state It can be seen that it is possible to secure a high adhesive strength even if the In addition, even when the placing process is performed after the cutting process and the watering process, the average adhesive strength is 1.99 (N/mm ² ), and the standard adhesive strength (1.5 N/mm ² or more ) is found to be higher than The preferred average value of the adhesive strength is 1.90 or more, more preferably 2.70 (N/mm ² ) or more, and more preferably 3.00 (N/mm ² ) or more.

1 Concrete floor slab (existing concrete member)
11 Pour joint surface 12 Convex portion 13 Concave portion 14 Concave and convex portion 21 Cement paste 22 Coarse aggregate 23 Fine aggregate 2 Pavement 3 Chipping machine 4 Vacuum vehicle 5 Formwork 6 Flow plate 7 Ultra high strength fiber reinforced concrete (fiber reinforced cement composite material)
S11 Cutting step S11A Concave-convex forming step S11AB Concave-convex joint surface forming step (concave-convex forming step)
S12 Watering step S13 Placement step S14 Curing step

Claims (7)

An inorganic material construction method for joining a fiber-reinforced cement composite material to an existing concrete member,
A cutting step of cutting the pavement provided on the surface of the existing concrete member to expose the joint surface of the existing concrete member;
a watering step of watering the joint surface with water so that the water is less than saturated;
a placing step of directly placing a fiber reinforced cement composite material on the sprinkling joint surface without using an adhesive ,
an unevenness forming step of forming an unevenness having a plurality of protrusions and recesses on the joint surface after the cutting step and before the watering step;
The placing step is a method of applying an inorganic material in which the fiber-reinforced cement composite material is directly placed on a joint surface on which irregularities are formed and water is sprinkled . In the unevenness forming step, the protrusions are formed on the joint surface by protrusions of cement paste, protrusions of fine aggregate, and protrusions of coarse aggregate. 2. The inorganic material construction method according to claim 1 , wherein the concave portion is formed with coarse aggregate other than fine aggregate, fine aggregate, and cement paste. 3. The method according to claim 2 , wherein the coarse aggregates and the fine aggregates forming the projections include a mixture of those whose surfaces are coated with the cement paste and those whose surfaces are exposed from the cement paste. Construction methods for inorganic materials. The method of applying an inorganic material according to any one of claims 1 to 3 , wherein the unevenness forming step forms the unevenness on the joint surface by water jet. 5. The method of applying an inorganic material according to claim 4 , wherein the unevenness forming step sets the discharge pressure of the water jet to a range of 70 MPa or more and 270 MPa or less. In the placing step, the fiber reinforced cement composite material is poured from one end side to the other end side of the joint surface, and the entire joint surface is covered by pouring the fiber reinforced cement composite material a plurality of times, 6. The method of applying an inorganic material according to any one of claims 1 to 5 , wherein thereafter, the entire joint surface is cured at once. In the placing step, the fiber-reinforced cement composite material is poured into each partitioned area while partitioning the joint surface from one end side to the other end side of the joint surface by the formwork, and a plurality of areas partitioned by the formwork are poured. 7. The inorganic material according to any one of claims 1 to 6 , wherein the pouring of the fiber-reinforced cementitious composite material per layer covers the entire pour joint surface and then the entire pour joint surface is cured at once. construction method.

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