Floor structure and method of manufacturing the same

Abstract

As a technique for smoothing the floor structure, for example, there is a self-leveling method, but in the conventional technique, the construction time of the floor structure cannot be sufficiently shortened. Thus, in the method of constructing a floor structure, the construction time can be shortened.SOLUTION: The method includes a placing step of placing a concrete composition containing water, cement, and aggregate, a coating step of coating the upper surface of the placed concrete composition with a slurry-like coating agent composition containing cement and an acrylic resin while the concrete composition is uncured, and a curing step of curing the coating agent composition after the coating step.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a floor structure and a method for manufacturing the same. [Background technology]

[0002] Concrete slabs are used when smoothness is required for floor structures such as logistics warehouses, complex facilities, sports facilities, factories, etc. The general construction method for concrete slabs is to pour ready-mixed concrete, level it, then apply pressure (trowel finish) to create a smooth surface.

[0003] Concrete is a material that hardens over time. For this reason, pouring and leveling should be done quickly, while the concrete is still fluid. After leveling, the work of removing the concrete and pressing it down is done by people or machines standing on top of the concrete. For this reason, it is necessary to gradually proceed with the work at the appropriate time while monitoring the state of the concrete hardening. The hardening speed of concrete is mainly affected by the temperature during construction, with concrete hardening faster in the summer when the ambient temperature is high and slower in the winter. If the concrete hardens slowly, the start time of the pressing work will be delayed. This means that it is difficult to sufficiently shorten the work time on site. In addition, after the pressing work, water is often sprayed on the concrete slab and a sheet is used to prevent the surface of the concrete slab from drying out. When using sheet curing, the sheet becomes waste after use.

[0004] One example of a technique for smoothing the surface of a concrete slab is the self-leveling method (Patent Document 1). According to the invention of Patent Document 1, powder is applied to the surface of bleeding concrete and mixed in to modify the concrete surface. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 1-208353 Summary of the Invention [Problem to be solved by the invention]

[0006] However, conventional techniques have not been able to sufficiently reduce the construction time for floor structures. The present invention aims to provide a floor structure construction method that can shorten construction time. [Means for solving the problem]

[0007] The present invention has the following aspects. <1> a concrete slab and a covering layer located on an upper surface of the concrete slab; A floor structure, wherein the coating layer is a hardened material containing cement and an acrylic resin. <2> The coating layer contains 50 mL to 75 mL of the acrylic resin per 1 kg of the cement. <1> The floor structure described in <3> The thickness of the coating layer is 1 to 10 mm. <1> or <2> The floor structure described in

[0008] <4> A method for manufacturing a floor structure having a concrete slab and a covering layer located on an upper surface of the concrete slab, comprising: A casting step of casting a concrete composition including water, cement, and aggregate; a coating step of coating a slurry-like coating composition containing cement and an acrylic resin on the top surface of the poured concrete composition while the concrete composition is still in an unhardened state; a curing step of curing the coating composition to form the coating layer after the coating step; A method for manufacturing a floor structure comprising: <5> The application step is carried out so that the penetration resistance of the poured concrete composition is 0.4 N / mm 2 That's it, <4> A method for manufacturing a floor structure according to claim 1. <6> The coating composition contains 50 mL to 75 mL of the acrylic resin per 1 kg of the cement. <4> or <5> A method for manufacturing a floor structure according to claim 1. [Effects of the Invention]

[0009] According to the floor structure construction method of the present invention, construction time can be shortened. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a floor structure according to an embodiment of the present invention. [Figure 2] FIG. 1 is a flow chart showing an example of a construction method for a floor structure of the present invention. [Figure 3] 10 is a graph showing the relationship between the environmental temperature and the elapsed time. [Figure 4] 1 is a photograph illustrating a method for measuring adhesive strength. [Figure 5] 1 is a cross-sectional photograph of the floor structure of Example 1. DETAILED DESCRIPTION OF THE INVENTION

[0011] In this specification and claims, the use of "to" indicating a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0012] (floor structure) The floor structure 1 of the present invention comprises a concrete slab 10 and a covering layer 20 located on the upper surface 11 of the concrete slab 10 .

[0013] <Concrete slab> The concrete slab 10 may be made of reinforced concrete, steel fiber concrete, or the like. The concrete slab 10 is a hardened concrete composition, which will be described later. The thickness of the concrete slab 10 is determined appropriately depending on the strength required for the floor structure.

[0014] <Coating layer> The coating layer 20 is a layer located on the upper surface 11 of the concrete slab 10. The coating layer 20 is a hardened product of a coating composition described below, and contains cement and an acrylic resin.

[0015] The thickness T20 of the covering layer 20 is determined appropriately taking into consideration the strength required for the floor structure 1. The thickness T20 is, for example, preferably 1 to 10 mm, and more preferably 3 to 5 mm.

[0016] <Effects> According to the floor structure of this embodiment, the upper surface of the concrete slab is covered with a coating layer, making the surface smooth. Furthermore, even if the concrete slab is made of steel fiber concrete, there is no need to remove the steel fibers exposed on the surface of the concrete slab.

[0017] (Floor structure manufacturing method) The method for manufacturing a floor structure of the present invention includes a pouring step, an application step, and a curing step. An example of a method for manufacturing a floor structure according to the present invention will be described below with reference to FIG.

[0018] The manufacturing method of the floor structure of this embodiment includes a pouring step S2, a leveling step S3, a roughening step S4, a coating step S5, a hardening step S6, and a curing step S7.

[0019] <Pouring process> The pouring step S2 is a step of pouring a concrete composition into a formwork. A concrete composition includes, for example, cement, aggregates (fine aggregate, coarse aggregate), and water. The amount of each component that constitutes the concrete composition is not particularly limited, and is determined appropriately taking into consideration the strength required for the concrete slab 10, etc. The casting step of this embodiment includes a concrete composition preparation operation and a casting operation. However, if a pre-prepared concrete composition is used, the casting step does not necessarily include the concrete composition preparation operation.

[0020] <Concrete composition preparation procedure> The concrete composition preparation operation is an operation for preparing a concrete composition.

[0021] The water is not particularly limited, and water that complies with JIS A 5308:2019 "Ready-mixed concrete" can be used.

[0022] The cement is not particularly limited as long as it is a powder that hardens by a chemical reaction with water and whose main raw material is limestone, clay, silica stone, iron oxide raw material, etc. Examples of cement include portland cement (JIS R 5210:2009), blast furnace cement (JIS R 5211:2009), silica cement (JIS R 5212:2009), fly ash cement (JIS R 5213:2009), and ecocement (JIS R 5214:2009).

[0023] The fine aggregate is not particularly limited, and may be any fine aggregate for concrete as specified in JIS A 5005:2020 "Crushed stone and crushed sand for concrete" or the like.

[0024] The coarse aggregate is not particularly limited, and may be any coarse aggregate for concrete as specified in JIS A 5005:2020 "Crushed stone and crushed sand for concrete" or the like.

[0025] When the concrete slab 10 is steel fiber concrete, the concrete composition includes steel fibers. The steel fibers may have a diameter of 0.3 to 1 mm and a length of 10 to 60 mm, for example. The shape of the steel fibers may be, for example, hook-shaped, straight-shaped, or wavy. In the case of steel fiber concrete, the amount of steel fiber per 100 parts by mass of cement is determined appropriately taking into consideration the required strength and the type of steel fiber.

[0026] The concrete composition can be prepared by a conventional method known in the art.

[0027] The concrete composition may contain components (other components) other than cement, acrylic resin, and steel fibers, as needed. Other ingredients include short fibers, water reducing agents, setting accelerators, etc. Examples of short fibers include steel fibers or resin fibers having a length of 0.1 to 1 mm. Examples of water-reducing agents include AE ​​water-reducing agents of lignin sulfonates. Examples of setting accelerators include aluminum sulfonates, melamine compounds, hydroxycarboxylates, and the like.

[0028] <Pouring operation> In the casting operation, the prepared concrete composition is poured (filled) into the formwork. The method of casting can be a conventional method for casting a concrete composition.

[0029] <Smoothing process> In the leveling step S3, the surface of the concrete composition poured in the pouring step S2 is leveled. That is, the leveling step S3 is performed on a concrete composition in a highly fluid state, and it is required to level the surface as quickly as possible after pouring.

[0030] For example, a rake, a drill bit, a metal trowel, an electric trowel, etc. are used to level the surface in the leveling step S3. Although the manufacturing method of the floor structure of the present embodiment includes the leveling step S3, the present invention is not limited to this, and the manufacturing method of the floor structure of the present invention does not necessarily have to include the leveling step S3.

[0031] <Amade process> The raking step S4 is a step of rubbing the surface of the poured concrete composition with a rotating disk or the like after the leveling step S3. The time from the end of the pouring step S2 until the start of the topping step S4 is determined appropriately depending on the temperature, humidity, etc. of the working environment. The timing (starting point) of starting the topping-out step S4 is preferably determined based on the hardening state of the poured concrete composition. 2 It is preferable to use a pressure of 0.5N / mm or more. 2 If the penetration resistance of the concrete composition is equal to or greater than the above lower limit, the surface of the concrete composition is less likely to sink when a worker works on the poured concrete composition while wearing mesh clogs or the like. The upper limit of the penetration resistance of the concrete composition at the start of the top-filling step S4 is 0.9 N / mm 2 If the upper limit of the penetration resistance value of the concrete composition is equal to or less than the above upper limit, it is possible to integrate the surface sludge (sludge that rises to the surface of the concrete during hardening) with the concrete while the concrete surface is in a soft state. In the sludge removal step S4, the penetration resistance value of the concrete composition is preferably 0.5 N / mm or less. 2 It is preferable that it is close to .

[0032] The penetration resistance value is a value measured by preparing a sample from the concrete composition, removing solid matter (coarse aggregate, etc.) of 0.5 mm or larger, and measuring this sample with a penetration resistance testing device in accordance with JIS A 1147:2019 Concrete Setting Time Test Method. That is, a sample is prepared separately from the pouring operation, and the penetration resistance value of this sample is measured at the same time as the pouring operation begins, and this is used as the penetration resistance value of the poured concrete composition.

[0033] At the end of the pitting step S4, the penetration resistance of the concrete composition is 0.9 N / mm 2 Less than 0.7N / mm is preferable. 2 Less than 0.6N / mm is more preferable. 2 The following is even more preferred: Components that have risen to the surface of the poured concrete composition before topping out may be removed as appropriate depending on their amount.

[0034] In the present invention, the topping-out step S4 may be omitted. However, from the viewpoint of smoothing the surface of the poured concrete composition and lifting the additives and the like, it is preferable that the manufacturing method of the floor structure of the present invention includes the topping-out step S4.

[0035] <Coating process> The coating step is a step of applying a coating composition to the top surface of the poured unhardened concrete composition. The coating step of this embodiment includes a coating composition preparation operation and a coating operation. However, if a pre-prepared coating composition is used, the coating step does not have to include the coating composition preparation operation.

[0036] <<Coating composition preparation procedure>> The coating composition preparation operation prepares a coating composition.

[0037] The coating composition is a slurry-like composition containing cement and an acrylic resin. The viscosity of the coating composition is not particularly limited, but is preferably 190 mm to 240 mm in terms of flow value. When the viscosity of the coating composition is equal to or higher than the lower limit, the thickness of the coating layer can be more easily adjusted. When the viscosity of the coating composition is equal to or lower than the upper limit, the coating composition can be applied more uniformly. The flow value is measured according to the Architectural Institute of Japan's Standard Specifications for Building Construction and Commentary, JASS 15 "M-103 Quality Standards for Self-Leveling Materials" (revised December 2019).

[0038] The cement in the coating composition is the same as the cement in the cement composition. The cement in the coating composition and the cement in the cement composition may be the same or different. The content of cement in the coating composition is determined appropriately depending on the viscosity and other properties required for the coating composition.

[0039] The acrylic resin in the coating composition is a polymer compound containing a (meth)acrylic acid ester or a derivative thereof as a constituent unit. In this embodiment, known acrylic resins can be used. The term "(meth)acrylic acid" refers to both methacrylic acid and acrylic acid.

[0040] Examples of acrylic resins include polymers containing, as a constituent element, a monomer (acrylic acid monomer) selected from acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, and N,N'-dimethylaminoethyl acrylate; methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl methacrylate, and N,N'-dimethylaminoethyl methacrylate; and (meth)acrylic acid or a derivative thereof, such as an amide acrylate such as (meth)acrylamide. The acrylic resin may contain structural units other than (meth)acrylic acid esters. The acrylic resin may also be a mixture of multiple types of acrylic resins.

[0041] The content of (meth)acrylic acid ester units in the acrylic resin is preferably 50 mol % or more, more preferably 80 mol % or more, and may be 100 mol % of the constituent units of the acrylic resin.

[0042] The water in the coating composition is the same as the water in the cement composition. The water in the coating composition and the water in the cement composition may be the same or different.

[0043] The coating composition can be prepared, for example, by mixing cement (powder), a slurry of an acrylic resin, and water in a predetermined ratio. The amount of cement mixed in the coating composition is, for example, preferably 20 to 30 kg, more preferably 23 to 27 kg, per 6 L of water. The amount of acrylic resin to be added to the coating composition is preferably 50 mL to 75 mL, and more preferably 60 mL to 65 mL, per 1 kg of cement. When the amount of acrylic resin is equal to or greater than the above-mentioned lower limit, the strength of the cured coating layer 20 can be further increased. This makes it possible to perform other work on the coating layer 20 the day after application, even in the cold winter weather, and prevents damage to the surface due to the work. In addition, when the content of acrylic resin is equal to or greater than the above-mentioned lower limit, the adhesive strength of the underlying concrete can be further increased. When the amount of acrylic resin is equal to or less than the above-mentioned upper limit, the viscosity of the coating composition can be reduced, improving application ease and increasing the smoothness of the surface after application, resulting in a better appearance. The content of water in the coating composition is determined appropriately taking into consideration the viscosity required for the coating composition. A part or all of the water in the coating composition may be water carried over from the raw material (for example, acrylic resin slurry).

[0044] The coating composition may contain other components (optional coating components) in addition to water, cement, and acrylic resin. Optional coating components include a curing accelerator, a pigment, and the like.

[0045] The method for preparing the coating composition is not particularly limited, and is appropriately determined depending on the form of the acrylic acid-based resin (powder, slurry, etc.). For example, when powdered cement and a slurry containing an acrylic resin are used as materials, the coating composition can be prepared by mixing these with water or optional coating components as needed using a mixer or the like.

[0046] <Application operation> In the application operation, the coating composition is applied to the top surface of the unhardened concrete composition that has been subjected to the basting process. The timing (starting point) of starting the application operation is preferably determined based on the hardening state of the poured concrete composition. 2 More than 0.9N / mm 2It is more preferable to carry out the application in the following manner. When the penetration resistance value of the concrete composition is equal to or greater than the above-mentioned lower limit, workers can stand on the concrete wearing mesh clogs, and work can be carried out without damaging the smoothness of the concrete surface, such as by causing depressions. In addition, when the penetration resistance value of the concrete composition is equal to or greater than the above-mentioned lower limit, the amount of concrete composition and coating composition mixed can be reduced, more reliably achieving the desired thickness of the coating layer 20 and more firmly adhering the concrete slab 10 and the coating layer 20 (i.e., peeling can be more effectively prevented). The upper limit of the penetration resistance value of the concrete composition in the application operation is 0.9 N / mm 2 Less than 0.7N / mm is preferable. 2 The following is more preferable: When the upper limit of the penetration resistance value of the concrete composition is equal to or less than the above upper limit, the covering layer 20 can adhere more firmly to the concrete slab 10 .

[0047] The method for applying the coating composition (application method) is not particularly limited as long as the coating composition can be spread over the top surface of the poured concrete composition. Examples of application methods include a method in which the coating composition is spread over the top surface of the poured concrete composition using a pump or the like and then left as is. Alternatively, examples include a method in which the coating composition is spread over the top surface of the poured concrete using a pump or the like and then spread using a tongs, rake, trowel, turntable, or the like. Alternatively, examples include a method in which the coating composition is spread over the top surface of the poured concrete using a coater.

[0048] The amount of coating composition to be applied in the coating operation can be determined appropriately taking into consideration the desired thickness of the coating layer 20, the water content in the coating composition, etc. For example, the amount of coating composition to be applied is 25 kg / m to achieve a thickness T20 of 2.5 mm. 2 is preferable, and 50 kg / m 2 is preferred. Therefore, the coating amount of the coating composition is 10 to 100 kg / m 2 is preferable, and 30 to 50 kg / m 2When the coating amount of the coating composition is equal to or greater than the above lower limit, the thickness T20 of the coating layer 20 can be sufficiently ensured. When the coating amount of the coating composition is equal to or less than the above upper limit, the curing time of the coating composition can be shortened, and the coating layer 20 can be formed in a shorter time.

[0049] Prior to the application operation, the surface of the poured concrete composition may be roughened.

[0050] <Curing process> The curing step S6 is a step of curing the applied coating composition to form the coating layer 20. The curing step S6 is carried out, for example, when the penetration resistance of the coating composition is 6 N / mm 2 The point at which this is reached is the end point. The time for the curing step S6 (coating layer curing time) varies depending on the temperature of the construction environment, but is, for example, 5 to 10 hours. If the curing time is equal to or greater than the lower limit, the applied coating composition spreads due to gravity, resulting in a more uniform thickness. If the curing time is equal to or less than the upper limit, the manufacturing time for the floor structure can be further shortened. The curing time can be adjusted by combining the composition of the coating composition, the temperature and humidity of the working environment, etc.

[0051] <Curing process> The curing step S7 promotes hardening of the cast concrete composition. The curing method is not particularly limited, and examples thereof include methods of covering the surface of the coating layer 20 with a sheet or water, such as water spray curing and sheet curing. In addition, the curing method of the curing step S7 of this embodiment may omit the step of covering the surface of the coating layer 20. This eliminates waste from the curing sheet and water for curing, thereby limiting the environmental load. The period of the curing step S7 (curing time) can be appropriately determined taking into consideration the composition of the concrete composition, the thickness of the concrete slab, and the like. After the pouring step S2, the poured concrete composition hardens until it reaches the curing step S7, and becomes the concrete slab 10.

[0052] <Other processes> The method for manufacturing a floor structure of the present invention may include steps other than those described above. For example, the method for manufacturing a floor structure may include a decorative step. The decorative step is a step of decorating the surface of the coating layer 20 after the curing step S6. Examples of the decorative step include polishing the surface of the coating layer 20 and applying a top coat.

[0053] <Effects> As described above, according to the method for manufacturing a floor structure of this embodiment, after the casting step, a coating composition is applied to the top surface of the unhardened concrete composition, and the coating composition is hardened to form a coating layer. The hardening rate of the coating composition is faster than the hardening rate of the concrete composition. In the present invention, the coating composition hardens quickly, so that the floor structure can be manufactured without the conventional pressing. This reduces the manufacturing time of the floor structure.

[0054] FIG. 3 shows an example of the effect of the present invention. FIG. 3 is a graph in which the horizontal axis represents elapsed time (work time) and the vertical axis represents environmental temperature (temperature of the work environment). As shown in Figure 3, the start time of the flaking process (start point of the flaking process) and the start time of the trowel finishing (start point of the press) vary greatly depending on the ambient temperature. For example, at an ambient temperature of 35°C, the time when the concrete starts to pour out (when the penetration resistance of the poured concrete composition is 0.5 N / mm 2 The time until the concrete composition reaches a penetration resistance of 6N / mm was 153 minutes, and then the time to start trowel finishing (the time until the concrete composition reaches a penetration resistance of 6N / mm 2 The time required for the concrete to reach the desired consistency is 69 minutes, and it takes 222 minutes from the pouring process to the start of the finishing touches with the trowel. For example, at an ambient temperature of 5°C, the time when the concrete starts to pour out (the penetration resistance of the poured concrete composition) is 0.5 N / mm 2 The time until the penetration resistance of the cast concrete composition reaches 6N / mm was 392 minutes, and then the time to start trowel finishing (the time until the penetration resistance of the cast concrete composition reaches 6N / mm 2 The time required for the concrete to reach a matt state is 319 minutes, and it takes 709 minutes from the pouring process to the start of the trowel finishing process. According to the present invention, by providing a coating process and a hardening process instead of a trowel finishing process, the time from the end of the basting process to the start of the curing process can be shortened, thereby shortening the manufacturing time of the floor structure.

[0055] According to the present invention, after the coating resin composition is applied, people can stand on the surface in a short time. Therefore, compared with the conventional pressing process, the time that workers are required can be reduced, and the work can be carried out with a minimum number of people. In particular, when carrying out work in winter (when the ambient temperature is low), the work time can be significantly reduced. In addition, unlike conventional slab structures, there is no work to be done the day before construction (tidying up, cleaning, applying primer, etc.), and less material is required (approximately one-third), so the labor required for transportation, mixing, application, etc. can be reduced. Compared to the conventional pressing process, this eliminates the need for watering or sheet curing after protection, saving manpower, water, and sheets. Because pressing work is no longer necessary, it also reduces fuel (gasoline, etc.) consumed by machines, CO2 emissions, and noise during late-night work. Furthermore, compared to the conventional pressing process, there is no need to rely on special skills because there is no need to keep track of the timing of the application.In the summer, when concrete hardens quickly and there is not enough time for construction, there is no need to secure many workers if the application method is mechanized, etc. When the floor structure of the present invention is used as a base for coated flooring or floor covering, the rise of moisture from the concrete is suppressed, which is effective in preventing the occurrence of problems such as swelling and peeling that are unique to coated flooring and floor covering. [Example]

[0056] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

[0057] (Raw materials used) · Concrete composition: a mixture of cement, aggregate and water. · Coating composition: Prepared by mixing 25 kg of cement, 125 mL of acrylic resin, and 6 L of water.

[0058] (Measurement method) <Adhesion strength> The method for measuring the adhesive strength will be explained with reference to FIG. Four incisions 22 were made on the surface (coating layer) of the floor structure 1 of each example, forming a 40 mm square. The square coating layer 24 formed by the four incisions was peeled off using a dedicated tensile strength tester, and the maximum value was measured and used as the adhesive strength. For each example, five measurements were made, and the average value was calculated.

[0059] (Examples 1 to 3) According to the manufacturing conditions in Table 1, the concrete composition is poured, and then a leveling process is carried out. The concrete composition is then poured on the top surface of the poured concrete composition with or without roughening. 2 The coating composition was applied (application step). 30 hours after application of the coating composition (hardening step, curing step), the floor structure of each example was obtained. The resulting floor structure was subjected to an adhesion test, the results of which are shown in the table.

[0060] [Table 1]

[0061] As shown in Table 1, in Examples 1 to 3 to which the present invention was applied, the average adhesive strength was 2.16 to 2.55 N / mm 2 In other words, the coating layer and the concrete slab were adhered with sufficient strength. 5 shows a cross-sectional photograph of the floor structure of Example 1. As shown in FIG. 5, no gap was formed at the interface 12 between the concrete slab 10 and the covering layer 20. [Explanation of symbols]

[0062] 1 floor structure 11 Top side 10 Concrete slab 20 Covering layer S2 pouring process S3 Leveling process S4 Thickening process S5 Coating process S6 Hardening Project S7 Wellness Project

Claims

1. a concrete slab and a covering layer located on an upper surface of the concrete slab; A floor structure, wherein the coating layer is a hardened material containing cement and an acrylic resin.

2. The floor structure according to claim 1, wherein the coating layer contains 50 mL to 75 mL of the acrylic resin per 1 kg of the cement.

3. The floor structure according to claim 1 or 2, wherein the thickness of the covering layer is 1 to 10 mm.

4. A method for manufacturing a floor structure having a concrete slab and a covering layer located on an upper surface of the concrete slab, comprising: A casting step of casting a concrete composition including water, cement, and aggregate; a coating step of coating a slurry-like coating composition containing cement and an acrylic resin on the top surface of the poured concrete composition while the concrete composition is still in an unhardened state; a curing step of curing the coating composition to form the coating layer after the coating step; A method for manufacturing a floor structure comprising:

5. The application step is carried out so that the penetration resistance of the poured concrete composition is 0.4 N / mm ２ The method for manufacturing a floor structure according to claim 4, which is carried out as described above.

6. The method for manufacturing a floor structure according to claim 4 or 5, wherein the coating composition contains 50 mL to 75 mL of the acrylic resin per 1 kg of the cement.

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