JP7271185B2 - Construction method of members - Google Patents

Description

The present invention relates to a member construction method. More particularly, the present invention relates to a construction method for members that can be used in construction of buildings and civil engineering structures.

Concrete, whose shape can be freely designed and whose durability is high, is an indispensable material in the fields of civil engineering and construction, and is widely used as a material for various structures.
For concrete structures, there are demands for further strength improvement, methods of repairing the surface layer cross-section, which is called the cover, which is the most susceptible to deterioration, and methods of strengthening the cover, among concrete structures that have been built for many years. There is a demand for , and various methods have been studied. As a conventional method for increasing the tensile strength of the cover portion of a concrete structure, a method of reinforcing the surface of an existing concrete structure with carbon fiber or a reinforcing bar of a predetermined diameter (see Patent Documents 1 and 2), High-strength fiber-reinforced concrete containing concrete is known (see Patent Documents 3 and 4). In addition, as a method of repairing concrete structures, there is a method of repairing concrete structures with polymer cement mortar using a polymer with a predetermined glass transition temperature, and a method of removing the surface concrete of an irrigation canal whose surface layer has deteriorated by chipping and then using a specific polymer. A method of applying cement mortar to form a repair material layer, a method of repairing the surface of a concrete structure with a cross-section repair material containing a special non-hydraulic compound, and a method of carbonating the surface after the cross-section repair material has hardened, etc. are known (see Patent Documents 5 to 7).

Among such concrete structures, agricultural waterways and dams are one of concrete structures that particularly require strength of the covering portion as a countermeasure against physical deterioration (countermeasure against reduction in cross section). Agricultural waterways are not only hit by water, but also sand, driftwood, etc., so abrasion resistance and strength are required. In addition, the dam is provided with a discharge facility for discharging surplus water, and in particular, a spillway is provided for the purpose of ensuring the safety of the dam during floods. Since the energy of the water discharged from the dam during flooding is extremely large, the spillway is equipped with a force-dissipating structure to control the water flow. This large amount of water energy is added to the energy dissipating structure, and driftwood and boulders that are washed away by the muddy current may collide with the energy dissipating structure. The reinforced concrete is damaged, and the cross section decreases with the passage of time. For this reason, the surface of the concrete forming the energy absorber is required to be made of a material with high abrasion resistance, and conventionally, the surface of the energy absorber is covered with a steel plate or the like. For dams, as a method of improving the wear resistance of the dam body, a method of laying reinforcing rails with detachably connected legs on the sloped water tapping section and pouring high-strength concrete is known ( Patent document 8).

JP-A-2001-32532 JP-A-2003-35041 JP 2017-110399 A JP 2018-91063 A JP 2006-124232 A JP 2011-148695 A Japanese Unexamined Patent Application Publication No. 2007-22878 JP-A-2002-69981

According to the Agricultural Civil Engineering Association, the concrete applied to agricultural waterways has the following characteristics when compared with a standard test specimen made by JIS mortar in terms of the depth of wear specified in the water-sand jet wear test after 10 hours: 1. 5 or less is set as a condition. Existing ultra-high-strength fiber-reinforced concrete is 0.32 when JIS mortar is used as a standard. As a result of Okuda's wear test devised by the Central Research Institute of Electric Power Industry after 4 hours, the wear coefficient of ultra-high-strength fiber-reinforced concrete is about 250 mm ³ /cm ² .
When a concrete structure is used for such a part that particularly requires abrasion resistance, ultra-high strength fiber reinforced concrete described in Patent Documents 3 and 4 and carbonation curing described in Patent Document 7 are applied. Applications such as long-life concrete made by densifying hardened surface concrete cement can be considered. However, ultra-high-strength fiber-reinforced concrete requires special fiber materials and concrete formulations, and long-life concrete requires the use of special admixture γ-C ₂ S and special equipment for carbonation curing. As a result, it is disadvantageous not only in terms of construction work but also in terms of cost, and it is difficult to adopt it. Therefore, there is a demand for a method that is superior to these in terms of workability and cost and that can construct a concrete structure that is superior in abrasion resistance.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a construction method capable of constructing a concrete structure excellent in workability, cost, and abrasion resistance.

The present inventor has studied a construction method that can construct a concrete structure that is excellent in terms of workability and cost and has excellent abrasion resistance, constructs reinforcing bars that are placed inside the member, and at least part of the surface of the member. After placing concrete in the area except for the surface layer, polymer cement mortar or polymer cement concrete is placed in the surface layer where concrete was not placed in the concrete placing process, and then the member is used for polymer cement. When the member is constructed by a process of heating at a temperature above the glass transition temperature of the polymer and at a temperature of 40 to 100 ° C., abrasion resistance and freeze-thaw resistance can be achieved while reducing the amount of polymer concrete that is more expensive than ordinary concrete. It was found that a concrete structure with excellent resistance can be constructed. Further, the present inventors have added a step of placing and heating polymer cement concrete, and a step of constructing reinforcing bars to be placed inside the member and placing concrete on at least a part of the surface of the member except for the surface layer. It was found that a method in which the order of the above is changed and a method using an embedded formwork can similarly construct a concrete structure that is excellent in both wear resistance and freeze-thaw resistance, and arrived at the present invention. be.

That is, the present invention is a method for constructing a member in which a part of the member is constructed from a material made of polymer cement, comprising a reinforcing bar assembling step for constructing a reinforcing bar to be placed inside the member, and a surface layer portion of at least a part of the surface of the member. and a polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete on the surface layer where concrete was not placed in the concrete placing step. and a heating step of heating the member after placing the polymer cement mortar or polymer cement concrete at a temperature higher than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C. It is a construction method of a member characterized by

The present invention also relates to a method of constructing a member in which a part of the member is constructed of a material made of polymer cement, wherein polymer cement mortar or polymer cement concrete is placed on at least a part of the surface of the member. / Concrete placing step, and heating to heat the surface layer portion on which the polymer cement mortar or polymer cement concrete is placed at a temperature equal to or higher than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C. a reinforcing bar assembling step for constructing reinforcing bars to be placed inside the member; and a concrete placing step for placing concrete in an area excluding the surface layer portion.

The invention further relates to a method of constructing a component in which a part of the component is constructed of a material consisting of polymer cement, the embedded form being arranged with an embedded formwork having a layer of polymer cement mortar or polymer cement concrete on at least part of the outside. a frame setting step; a reinforcing bar assembling step of constructing reinforcing bars inside the embedded form; and a concrete casting step of placing concrete inside the embedded form, wherein the embedded form is polymer cement mortar or Construction of a member characterized in that it is constructed through a heating step of heating a cement concrete layer at a temperature higher than the glass transition temperature of the polymer used in the polymer cement and at a temperature of 40 to 100 ° C. It is also a construction method.

The heating step is preferably performed at a temperature of 50 to 100°C.

The polymer used in the polymer cement preferably has a glass transition temperature of 35 to 100°C.

The member construction method of the present invention is a construction method that can construct a concrete structure excellent in abrasion resistance while suppressing the cost, so that it can be used for constructing various concrete structures. Among others, it can be suitably used for constructing the surfaces of agricultural waterways and dam spillway energy absorbers that require abrasion resistance, and the surface layers of the outer shell of gravity-type concrete dam bodies.

It is the figure which showed an example of embodiment of the 1st construction method of this invention. It is the figure which showed an example of embodiment of the 1st construction method of this invention. It is the figure which showed an example of embodiment of the 1st construction method of this invention. It is the figure which showed an example of embodiment of the 1st construction method of this invention. It is the figure which showed an example of embodiment of the 2nd construction method of this invention. It is the figure which showed an example of embodiment of the 2nd construction method of this invention. It is the figure which showed an example of embodiment of the 3rd construction method of this invention. It is the figure which showed an example of embodiment of the 3rd construction method of this invention. It is the figure which showed an example of embodiment of the 3rd construction method of this invention. It is the figure which showed an example of embodiment of the 3rd construction method of this invention. FIG. 10 shows the results of abrasion resistance evaluation of Example 7, Comparative Examples 5 and 7, and Reference Examples 1 and 2.

The present invention will be described in detail below.
A combination of two or more of the individual preferred embodiments of the invention described below is also a preferred embodiment of the invention.

One of the features of the construction method of the members of the present invention is the use of polymer cement mortar/concrete. Polymer cement mortar/concrete does not require special curing, can be cast on site, and does not require special equipment. In terms of cost, there is also the advantage that concrete having abrasion resistance equivalent to that of the above-described ultra-high-strength fiber-reinforced concrete and long-life concrete can be provided at a lower cost. Furthermore, in the construction method of the member of the present invention, the surface layer of the member, which requires high abrasion resistance, is formed with polymer cement mortar/concrete, and the inside of the other member is formed with ordinary concrete, thereby further reducing the cost. Realized.
Further, the construction method of the members of the present invention is also applied to the surface layers of structures applied to cold regions. For example, it is the outer shell of a concrete gravity dam built in a cold region such as a mountainous area. Such areas require high freeze-thaw resistance, and according to JIS A 1148 "Concrete freeze-thaw test method", conditions are set for a relative dynamic modulus of elasticity of 60% or more in a freeze-thaw test of 300 cycles. ing.
Structural members/structures having a polymer cement mortar/concrete layer on the surface layer constructed by the construction method of the present invention have high abrasion resistance as well as high freeze-thaw resistance. In other words, it has the performance that satisfies the above-mentioned technical standards for the freeze-thaw resistance of concrete structures.
The application of polymer cement mortar/concrete to concrete surface structures requiring such high abrasion resistance and high freeze-thaw resistance has hitherto been unprecedented.
The inventors of the present invention focused on such high durability performance of polymer cement mortar/concrete and proceeded with earnest research and development, and the performance that can solve the problems of the present invention is guaranteed by experiments etc. assuming actual application described later. We are confirming that.

There are the following three construction methods for the member construction method of the present invention.
(1) A reinforcing bar assembly process for constructing reinforcing bars to be placed inside the member, and a concrete placing process for placing concrete in an area excluding at least a part of the surface of the member, and A method in which polymer cement mortar or polymer cement concrete is placed on the surface layer where is not placed and heated at a predetermined temperature (hereinafter referred to as the first method of the present invention).
(2) A step of casting polymer cement mortar or polymer cement concrete on at least a part of the surface layer of the surface of the member, and a step of heating the surface layer on which the polymer cement mortar or polymer cement concrete is cast at a predetermined temperature. , a reinforcing bar assembly step, and a concrete placing step of placing concrete in an area excluding the surface layer where the polymer cement mortar or polymer cement concrete is placed (hereinafter referred to as the second method of the present invention). description)
(3) An embedded type in which an embedded form having a polymer cement mortar or polymer cement concrete layer constructed through a heating process of heating the polymer cement mortar or polymer cement concrete layer at a predetermined temperature is arranged at least partly outside. A method of performing a frame setting process, a reinforcing bar assembling process of constructing reinforcing bars inside the embedded form, and a concrete placing process of placing concrete inside the embedded form (hereinafter referred to as the third method of the present invention).
In the following, these three construction methods will be described in order, and then materials such as polymer cement mortar or polymer cement concrete used in the construction method of the members of the present invention will be described.

1. First construction method of the present invention In the first construction method of the present invention, concrete is first placed in areas other than the surface layer where the polymer cement mortar or polymer cement concrete is to be placed, and then at least a part of the surface layer is coated with polymer. This is a construction method in which cement mortar or polymer cement concrete is placed and heated to a predetermined temperature, and the inside is placed first.
1 and 2 are diagrams showing one embodiment of constructing floor slabs, water conduits, etc. in cold districts by the first construction method of the present invention. The first construction method will be described with reference to these drawings.
In the first construction method of the present invention, first, a reinforcing bar assembling step of constructing the reinforcing bars 1 inside the member and a concrete placing step of placing concrete 2 in at least a part of the surface of the member except for the surface layer are performed. will be In FIG. 1, a reinforcing bar 1 to be placed inside a member is assembled, and concrete 2 is placed leaving a part of the upper part of the reinforcing bar. In the concrete placing process, ordinary concrete is placed.

In the first construction method of the present invention, before the above-mentioned concrete placing step, a partition member is installed to separate the surface layer where the polymer cement mortar or polymer cement concrete is placed and the area excluding the surface layer. It is preferred to carry out the steps. By performing the partition member installation process, the surface layer where polymer cement mortar/concrete is to be placed and the other parts can be clearly separated, and the surface layer where polymer cement mortar or polymer cement concrete will be placed later. can be secured.

Next, a polymer cement mortar/concrete placing step is performed to place polymer cement mortar or polymer cement concrete 3 on the surface layer where concrete 2 has not been placed. and a heating step of heating at a temperature of 40 to 100°C. After heating, it is desirable to subject the member to air or dry curing. Here, air curing is a curing method in which the material is exposed to the air without adding moisture, and dry curing is a method of actively drying by giving a temperature history etc. among air curing. Curing method including process.
In FIG. 2, polymer cement mortar or polymer cement concrete 3 is placed on the surface layer including the upper portion of the reinforcing bar 1 where the ordinary concrete 2 was not placed. The reinforcing bars of the surface layer may be constructed integrally with the reinforcing bars of the lower reinforced concrete, or may be the reinforcing bars connected to the reinforcing bars protruding upward from the lower reinforced concrete.

In the polymer cement mortar/concrete placing step, it is preferable to perform vibration compaction using a vibrator in order to achieve integration with previously placed ordinary concrete. By this operation, the plain concrete 2 and the polymer cement mortar/concrete 3 are fully integrated.
After such a polymer cement mortar/concrete placing step, it is not possible to include a compaction integration step of compacting and integrating the concrete placing portion and the polymer cement mortar/concrete placing portion by vibration with a vibrator. , is a preferred embodiment of the first construction method of the present invention.
In the case of FIG. 2, by inserting the vibrator 4 to the depth of the lower ordinary concrete layer and performing vibration compaction, the lower ordinary concrete 2 and the upper polymer cement mortar/concrete 3 are sufficiently integrated.

In the first construction method of the present invention, the polymer cement mortar/concrete kneading step is carried out before the polymer cement mortar/concrete placing step, in which the polymer is post-added to the agitator wheel to knead the polymer cement mortar/concrete. is preferred. By doing so, it is possible to manufacture polymer cement mortar/concrete without installing special equipment in the plant.

After the above-mentioned polymer cement mortar/concrete placing step, it is preferable to carry out the surface compaction and finishing step before the heating step. This step can be performed by a tamper, a leveling machine for trowel finishing, or the like.
Moreover, it is preferable to carry out a wet curing step after the polymer cement mortar/concrete placing step and before the heating step. As a result, the hydration reaction of cement in the concrete is promoted, resulting in highly durable concrete. Wet curing can be carried out by flooding curing or sheet curing, and the wet curing period is preferably 3 days or more. More preferably, it is 3 to 7 days.

In the heating step, the heating method is not particularly limited as long as it is heated at a temperature higher than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C. For example, the surface layer portion It can be carried out by arranging a heater such as a jet heater or a film heater to heat the surface layer. If the area to be heated is small, the heat may be supplied by an eye lamp.
The heating in the heating step may be performed at a temperature above the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C. However, by giving a higher temperature history, the polymer cement mortar / concrete Since the effect of improving the strength is exhibited, it is preferable to heat at a temperature as high as possible, preferably at 50 to 100°C. More preferably, it is 60°C to 100°C. After heating, it is desirable to subject the member to air or dry curing.

As another embodiment of the first construction method of the present invention, a case of constructing a wall of a channel or the like is shown in FIGS.
In this embodiment, first, a formwork 5 is arranged, and a reinforcing bar assembling process is performed in which the reinforcing bars 1 are assembled within the formwork. At that time, a partition member 6 is arranged at the boundary between the wall portion serving as the end portion and the region on the central portion side. As the partition member, a lath net, an air tube, a comb for fixing joints of concrete, etc., which are embedded in the formwork, can be used. A reinforcing bar 1 (horizontal reinforcing bar in the drawing) is passed through the partition member 6 and fixed to the reinforcing bar 1 . In this state, a concrete placing step is performed to place ordinary concrete 2 on the center side (Fig. 3).

Next, a polymer cement mortar/concrete placing step is performed to place polymer cement mortar/concrete 3 on the wall portion that will be the end portion (Fig. 4). After the polymer cement mortar/concrete placing step, it is preferable to carry out the above-described compaction and integration step using a vibrator in order to integrate the polymer cement mortar/concrete with the previously placed ordinary concrete 2 .

After the concrete develops a predetermined demolding strength (approximately 5 N/mm ² ) by hydration reaction, a demolding step of demolding the formwork is carried out. The period until the demolding step is performed is not particularly limited, and it may be after the predetermined demolding strength is developed. .

A wet curing step is preferably performed between the polymer cement mortar/concrete placing step and the demolding step. As a result, the hydration reaction of cement in the concrete is promoted, resulting in highly durable concrete. The wet curing period is preferably 3 days or longer. More preferably, it is 3 to 7 days.
After that, a heating process is performed. The heating step can be performed in the same manner as described above.

2. Second construction method of the present invention In the second construction method of the present invention, polymer cement mortar or polymer cement concrete is placed on at least a part of the surface layer of the member, and after heating to a predetermined temperature, This is a construction method in which the outside is placed first, with concrete being placed in the part of the
5 and 6 are diagrams showing one embodiment of constructing a member by the second construction method of the present invention. This embodiment is for pre-casting polymer cement mortar or polymer cement concrete only on the outer surface of a wall member or plate (slab) member. The second construction method will be explained using these figures.
In this embodiment, first the formwork 5 is placed and the reinforcing bars 1 are assembled in the formwork. At this time, a partition member 6 is arranged at the boundary between the outer surface of the wall (on the left side in FIG. 5) and the area on the central side. As the partition member, a lath net, an air tube, a comb for fixing joints of concrete, etc., which are embedded in the formwork, can be used. The partition member 6 is fixed to the force distributing bar (reinforcing bar perpendicular to the plane of FIG. 5).

First, the step of placing the polymer cement mortar/concrete 3 on the outer surface of the wall (left side in FIG. 5) and the lower surface of the slab (lower side in FIG. 5) is performed.
In the second construction method of the present invention, as described above, before the step of placing the polymer cement mortar/concrete, a partition member is arranged to separate the surface layer portion where the polymer cement mortar/concrete is placed from the other portion. It is preferable to perform a partition member installation step. As a result, it is possible to ensure the division between the surface layer portion where the polymer cement mortar/concrete is placed and the other portion.

The second construction method of the present invention also includes a polymer cement mortar/concrete kneading step of kneading the polymer cement mortar/concrete by post-adding the polymer to the agitator wheel before the polymer cement mortar/concrete placing step. is preferred. By doing so, it is possible to manufacture polymer cement mortar/concrete without installing special equipment in the plant.

After that, the process of placing ordinary concrete on the wall center side and the slab upper side is performed (Fig. 6).
At this time, in order to integrate the polymer cement concrete or polymer cement mortar on the outer surface with the ordinary concrete on the inner side, it is preferable to perform vibration compaction by inserting a vibrator into the boundary. Vibratory compaction can be performed in the manner described above.
That is, in the second construction method of the present invention as well, after the normal concrete placing step, the compacting and integration step of integrating the polymer cement mortar/concrete placing portion and the concrete placing portion by vibration with a vibrator is performed. is the preferred embodiment.

Thereafter, after the concrete develops a predetermined demolding strength (approximately 5 N/mm ² ) through a hydration reaction, a demolding step of demolding the formwork is performed. The period until the demolding step is performed is not particularly limited, and it may be after the predetermined demolding strength is developed. .

A wet curing step is preferably performed between the polymer cement mortar/concrete placing step and the demolding step. As a result, the hydration reaction of cement in the concrete is promoted, resulting in highly durable concrete. The wet curing period is preferably 3 days or more. More preferably, it is 3 to 7 days.
After that, a heating process is performed. The heating step can be performed in the same manner as described above.

3. Third construction method of the present invention In the third construction method of the present invention, an embedded form having a polymer cement mortar or polymer cement concrete layer heated to a predetermined temperature on at least a part of the outside is placed, and the inner side of the embedded form is placed. This is a construction method in which concrete is placed in the
7 and 8 are diagrams showing one embodiment of constructing a member by the third construction method of the present invention. This embodiment is an embodiment in which polymer cement mortar/polymer cement concrete is arranged as an embedded formwork only on the outer surface of gutter-like members, culverts, and plate (slab) members that form water channels. The third construction method will be described using these figures.
In the third construction method, an embedded formwork 7 having a layer of polymer cement mortar or polymer cement concrete heated to a predetermined temperature on at least a part of the outside is used.

The embedded formwork is prepared by casting polymer cement mortar or polymer cement concrete in advance in part or all of the formwork for creating the embedded formwork, and the temperature is higher than the glass transition temperature of the polymer used for the polymer cement, and It can be produced by heating at a temperature of 40 to 100° C. and then demolding. The embedded formwork, in which only a part of the formwork is formed by a layer of polymer cement mortar or polymer cement concrete, is partitioned by arranging a partition member in the formwork for creating the embedded formwork. It can be prepared by placing polymer cement mortar or polymer cement concrete in a part of the formwork and placing ordinary concrete in the other part.
The embedded formwork is preferably subjected to steam curing at a precast factory that creates the embedded formwork. At that time, since the effect of improving the strength is exhibited by giving a higher temperature history, it is preferable to cure at the highest possible temperature in the steam curing tank of the precast factory. After steam curing, it is desirable to subject the member to air or dry curing. When making an embedded formwork, it is possible to produce polymer cement mortar/concrete in the same process as ordinary concrete production by putting the polymer emulsion in the admixture tank of the plant.

In the embodiment of Figure 7, an embedded formwork 7 having at least part of the outside a layer of polymer cement mortar/concrete heated at a predetermined temperature is placed and the reinforcing bars 1 are assembled in the formwork. After that, the formwork 5 is placed and ordinary concrete is placed between the embedded formwork 7 and the formwork 5 (Fig. 8).

Thereafter, after the concrete develops a predetermined demolding strength (approximately 5 N/mm ² ) through a hydration reaction, a demolding step of demolding the formwork is performed. The period until the demolding step is performed is not particularly limited, and it may be after the predetermined demolding strength is developed. .

9 and 10 are diagrams showing another embodiment of constructing members by the third construction method of the present invention. FIGS. 9 and 10 show an embodiment for constructing an embedded form made of polymer cement mortar/concrete so as to form the floor slab surface layer of a highway or the like.
In the embodiment of FIG. 9, the embedded formwork 7 and the formwork 5 with the polymer cement mortar/concrete layer on at least part of the outside are placed facing downwards and the reinforcing bars 1 are assembled on the inside . After that, ordinary concrete 2 is placed inside the formwork, and after the concrete develops a predetermined demolding strength (approximately 5 N/mm ² ) due to hydration reaction, it is turned over (Fig. 10) and the formwork is demolded. .

4. Materials Used in the Member Construction Method of the Present Invention Next, materials used in the member construction method of the present invention will be described.
<Polymer>
The polymer cement mortar and polymer cement concrete used in the present invention are obtained by adding a polymer to the cement mortar and cement concrete materials and kneading them. By using such polymer cement mortar and polymer cement concrete, the structure constructed by the member construction method of the present invention has excellent wear resistance and strength. .
The polymer preferably has a glass transition temperature (Tg) of 35 to 100°C. When a polymer having such a Tg is used, the strength of polymer cement mortar and polymer cement concrete becomes higher and the abrasion resistance is also excellent. The Tg of the polymer is more preferably 35-90°C, more preferably 35-70°C, particularly preferably 35-60°C, most preferably 35-50°C.
Note that the glass transition temperature (Tg) of the polymer can be controlled by the type and usage ratio of the monomer components that are the raw materials of the polymer. Calorimeter) or DTA (differential thermal analysis).

In the formula, Tg' is the Tg (absolute temperature) of the copolymer emulsion particles. W1', W2', . . . Wn' are the mass fractions of each monomer relative to the total monomer components. Tg1, Tg2, . . . Tgn are glass transition temperatures (absolute temperatures) of homopolymers (single polymers) composed of respective monomer components. For the glass transition temperature of the homopolymer used in the above calculation, the value described in the literature can be used, for example, "POLYMER HANDBOOK 3rd Edition" (published by John Wiley & Sons, Inc.), etc. .

The above polymer preferably has an acid value of 5-100. When the acid value is 100 or less, the polymer has an appropriate viscosity and is easy to produce. The acid value of the polymer is more preferably 5-50, still more preferably 5-25, and particularly preferably 10-20.

The above polymer is preferably in the form of an emulsion. The polymer emulsion may contain one type of polymer or may contain two or more types. The polymer emulsion also preferably contains a polymer having monomeric units with carboxylic acid (salt) groups. The carboxylic acid (salt) group means a carboxylic acid group and/or a carboxylic acid group.
As the salt of the carboxylic acid base, metal salts, ammonium salts, organic amine salts and the like are preferred. Examples of metal atoms forming metal salts include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; divalent metal atoms such as calcium and magnesium; trivalent metal atoms such as aluminum and iron. Atoms are more preferred. As the organic amine salt, alkanolamine salts such as ethanolamine salts, diethanolamine salts and triethanolamine salts, and alkylamine salts such as triethylamine salts are more preferable.

As the monomer having a carboxylic acid (salt) group, a (meth)acrylic acid (salt)-based monomer is preferable. The (meth)acrylic acid (salt)-based monomer has at least one acryloyl group or methacryloyl group, or a group in which the hydrogen atom in these groups is replaced with another atom or atomic group, and A monomer having a carboxylic acid group (--COOH group), a salt thereof, or an acid anhydride group (--C(=O)--OC(=O)-- group) comprising a carbonyl group in the group is.
Examples of the salt of the (meth)acrylic acid-based monomer (acid group-containing monomer) include those similar to the salt of the carboxylic acid base.
The (meth)acrylic acid (salt)-based monomer is preferably (meth)acrylic acid or a salt thereof.

The polymer emulsion preferably contains a (meth)acrylic polymer. The (meth)acrylic polymer preferably contains structural units derived from (meth)acrylic monomers other than (meth)acrylic acid (salt) monomers. A (meth)acrylic monomer other than a (meth)acrylic acid (salt) monomer refers to a monomer having a structure in which the carboxylic acid group of (meth)acrylic acid is an ester, or a derivative of such a monomer. The ester may have an alkyl group (alkyl ester portion), and the alkyl ester portion may contain a functional group (hydroxyl group, amino group, glycidyl group, etc.). The (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer may contain one or more acryloyl groups or methacryloyl groups.

The monomer component for obtaining the (meth)acrylic polymer includes a (meth)acrylic acid (salt)-based monomer and a (meth)acrylic monomer other than the (meth)acrylic acid (salt)-based monomer. may contain other copolymerizable unsaturated bond-containing monomers. Therefore, the (meth)acrylic polymer includes structural units derived from (meth)acrylic acid (salt) monomers and structural units derived from (meth)acrylic monomers other than (meth)acrylic acid (salt) monomers. In addition, it may contain structural units derived from other copolymerizable unsaturated bond-containing monomers.
By including a (meth)acrylic acid (salt) monomer in the monomer component for obtaining the (meth)acrylic polymer, the cement dispersibility of the resulting polymer emulsion is improved. In addition, by including (meth) acrylic monomers other than (meth) acrylic acid (salt) monomers and other copolymerizable unsaturated bond-containing monomers, the acid value and glass transition temperature (Tg) of the polymer etc., can be easily adjusted. The unsaturated bond of the unsaturated bond-containing monomer is preferably a carbon-carbon double bond.

The (meth)acrylic polymer includes, for example, 0.6 to 12% by mass of (meth)acrylic acid (salt)-based monomers, and (meth)acrylic acid (salt)-based monomers other than (meth)acrylic monomers and It is preferably obtained by copolymerizing a monomer component composed of 88 to 99.4% by mass of other copolymerizable unsaturated bond-containing monomers. In the monomer component, the (meth)acrylic acid (salt)-based monomer is 0.8% by mass or more, and the (meth)acrylic acid (salt)-based monomer other than the (meth)acrylic acid (salt)-based monomer and other copolymerizable It is more preferable that the unsaturated bond-containing monomer is 99.2% by mass or less, the (meth)acrylic acid (salt) monomer is 1.0% by mass or more, and the (meth)acrylic acid (salt) monomer is other than The (meth)acrylic monomer and other copolymerizable unsaturated bond-containing monomers are more preferably 99.0% by mass or less, and the (meth)acrylic acid (salt) monomer is 1.2% by mass or more. and (meth) acrylic monomers other than (meth) acrylic acid (salt) monomers and other copolymerizable unsaturated bond-containing monomers are particularly preferably 98.8% by mass or less. In addition, in the monomer component, the (meth)acrylic acid (salt)-based monomer is 6% by mass or less, and (meth)acrylic acid (salt)-based monomers other than (meth)acrylic acid (salt)-based monomers and other copolymerizable It is more preferable that the unsaturated bond-containing monomer is 94% by mass or more, the (meth)acrylic acid (salt) monomer is 3% by mass or less, and the (meth)acrylic acid (salt) monomer other than the (meth) More preferably, the content of acrylic monomers and other copolymerizable unsaturated bond-containing monomers is 97% by mass or more. By setting it within such a range, the monomer component is stably copolymerized.

Examples of (meth)acrylic monomers other than the (meth)acrylic acid (salt) monomers include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, and butyl acrylate. , butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, pentyl acrylate, pentyl methacrylate, isoamyl acrylate, isoamyl methacrylate, hexyl acrylate, hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, octyl acrylate, octyl methacrylate, isooctyl acrylate, isooctyl methacrylate, nonyl acrylate, nonyl methacrylate, isononyl acrylate, isononyl methacrylate, decyl acrylate, decyl methacrylate, dodecyl acrylate, dodecyl methacrylate, tridecyl acrylate, tridecyl methacrylate, hexadecyl acrylate, hexadecyl methacrylate, C4-C30 (meth)acrylic acid alkyl esters such as octadecyl acrylate, octadecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate; 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2 - C4-C30 (meth)acrylic acid hydroxyalkyl esters such as hydroxypropyl methacrylate; ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1 ,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, polyfunctional (meth)acrylates such as glycidyl (meth)acrylate, etc., and one or two of these It is preferred to use the above.

The (meth)acrylic acid (salt)-based monomers other than the (meth)acrylic acid (salt)-based monomers are used as the raw material for the (meth)acrylic-based polymer, and the amount of the (meth)acrylic-based monomers is 20% by mass or more based on 100% by mass of the total monomer components. It is preferably contained, more preferably 40% by mass or more, and even more preferably 60% by mass or more. Further, the (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer preferably contains 99.9% by mass or less with respect to 100% by mass of the total monomer components, and 99.5% by mass. It is more preferable to contain the following.

The (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer contained in the above monomer component preferably contains a (meth)acrylic acid alkyl ester having 4 to 30 carbon atoms as a main component. More preferably, it contains 50% by mass or more of a (meth)acrylic acid alkyl ester having 4 to 30 carbon atoms with respect to 100% by mass of all monomer components that are raw materials for the (meth)acrylic polymer, and even more preferably , 70% by mass or more.

Other copolymerizable unsaturated bond-containing monomers other than the above (meth)acrylic acid (salt)-based monomers and (meth)acrylic acid (salt)-based monomers other than (meth)acrylic acid (salt)-based monomers include aromatic Examples thereof include monomers containing rings and copolymerizable unsaturated bonds.

Examples of the monomer containing an aromatic ring and a copolymerizable unsaturated bond include divinylbenzene, styrene, α-methylstyrene, vinyltoluene, ethylvinylbenzene, and the like, preferably styrene. Thus, other copolymerizable unsaturated bond-containing monomers other than (meth)acrylic acid (salt)-based monomers and (meth)acrylic acid (salt)-based monomers By appropriately selecting and using the type and blending amount, it becomes possible to control the polymer properties relatively easily.

When the monomer component that is the raw material for the (meth)acrylic polymer contains the monomer containing the aromatic ring and the copolymerizable unsaturated bond, it may contain 1% by mass or more in 100% by mass of the total monomer component. Preferably, it is contained in an amount of 5% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, and particularly preferably 40% by mass or more. In addition, the monomer component preferably contains 80% by mass or less, more preferably 70% by mass or less, of the monomer containing the aromatic ring and the copolymerizable unsaturated bond in 100% by mass of the total monomer component. , 60% by mass or less. It is to be noted that a monomer containing an aromatic ring and a copolymerizable unsaturated bond may not be used as the raw material of the (meth)acrylic polymer.

Other copolymerizable unsaturated bond-containing monomers other than the above include crotonic acid, tiglic acid, 3-methylcrotonic acid, 2-methyl-2-pentenoic acid, maleic acid, itaconic acid, mesaconic acid, citraconic acid, acid (salt)-based monomers other than (meth)acrylic acid (salt)-based monomers such as fumaric acid and salts thereof; fatty acid vinyl esters having 3 to 10 carbon atoms such as vinyl formate, vinyl acetate and vinyl propionate; diallyl phthalate, polyfunctional compounds such as triallyl cyanurate, acrylonitrile, trimethylolpropane diallyl ether; nitrogen atom-containing monomers such as methacrylonitrile, (meth)acrylamide, diacetone acrylamide; can be used.

When the monomer component that is the raw material for the (meth)acrylic polymer contains an acid (salt) monomer other than the (meth)acrylic acid (salt) monomer, 0.1 in 100% by mass of the total monomer component It is preferable to contain up to 5% by mass. It is more preferably contained in an amount of 0.3 to 4% by mass, and still more preferably in an amount of 0.5 to 3% by mass.
The monomer component that is the raw material for the (meth)acrylic polymer contains other copolymerizable unsaturated bonds other than acid (salt) monomers other than (meth)acrylic acid (salt) monomers. When a monomer is contained, it is preferably contained in an amount of 1.1 to 12% by mass based on 100% by mass of all monomer components. It is more preferably contained in an amount of 1.3 to 10% by mass, and still more preferably in an amount of 1.5 to 8.0% by mass.

The polymer emulsion preferably contains an aqueous solvent as a solvent for forming the emulsion. The aqueous solvent may contain other organic solvents as long as it contains water, but preferably contains only water as a solvent.

The amount of the aqueous solvent contained in the polymer emulsion is preferably 40 to 80% by mass with respect to 100% by mass of the polymer emulsion as a whole. More preferably 45 to 72% by mass, still more preferably 50 to 71% by mass.

The polymer contained in the polymer emulsion preferably has a weight average molecular weight of 10,000 to 500,000. With such a weight average molecular weight, water resistance can be imparted. The weight average molecular weight is more preferably 20,000 to 250,000, still more preferably 30,000 to 200,000.
The weight average molecular weight of the polymer can be measured using GPC under the following conditions.
Measuring instrument: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Molecular weight column: TSK-GEL GMHXL-L and TSK-GELG5000HXL (both manufactured by Tosoh Corporation) connected in series Eluent: Tetrahydrofuran (THF)
Standard material for calibration curve: Polystyrene (manufactured by Tosoh Corporation)
Measurement method: The object to be measured is dissolved in THF so that the solid content becomes about 0.2% by mass, filtered through a filter, and the molecular weight is measured as a measurement sample.

Although the pH of the polymer emulsion is not particularly limited, it is preferably 2-10. When the pH is within such a range, the resin can stably exist in the emulsion. The pH is more preferably 3-9.5, even more preferably 7-9. The pH of the emulsion can be adjusted by adding aqueous ammonia, water-soluble amines, an aqueous alkali hydroxide solution, or the like to the resin.

Although the viscosity of the polymer emulsion is not particularly limited, it is preferably 1 to 10000 mPa·s. When the viscosity of the resin emulsion is in such a range, it becomes possible to mix easily when actually preparing the polymer cement. The viscosity is more preferably 5 to 4000 mPa·s, still more preferably 10 to 2000 mPa·s.
The viscosity of the polymer emulsion can be measured with a Brookfield viscometer.

The polymer emulsion preferably has emulsion particles with an average particle size of 10 to 5000 nm. It is more preferably 50 to 500 nm, still more preferably 80 to 200 nm.
The average particle size of emulsion particles of the polymer emulsion can be measured by dynamic light scattering measurement.

The polymer emulsion can be produced by emulsion polymerization of monomer components as raw materials. The form of emulsion polymerization is not particularly limited, and for example, it can be carried out by appropriately adding a monomer component, a polymerization initiator and an emulsifier to an aqueous medium and then polymerizing. A polymerization chain transfer agent or the like may also be used for molecular weight control.

The water-based solvent is not particularly limited, and examples thereof include water, a mixed solvent of one or more solvents miscible with water, and a mixed solvent in which such a solvent is mixed so that water is the main component. etc. Among these, water is preferred.

As the emulsifier, polymerization initiator, and polymerization chain transfer agent, for example, those described in WO2007/023819 can be appropriately selected and used.

The above polymerization may be carried out in the presence of a chelating agent such as sodium ethylenediaminetetraacetate, a dispersant such as sodium polyacrylate, an inorganic salt, or the like, if necessary. Moreover, as a method of adding the monomer component, the polymerization initiator, etc., for example, a batch addition method, a continuous addition method, a multistage addition method, or the like can be applied. Also, these addition methods may be combined as appropriate.

Regarding the polymerization conditions in the above production method, the polymerization temperature is not particularly limited, and for example, it is preferably 0 to 100°C, more preferably 40 to 95°C. The polymerization time is also not particularly limited, and for example, it is preferably 1 to 15 hours, more preferably 2 to 10 hours.
The method of adding the monomer component, the polymerization initiator, etc. is not particularly limited, and for example, a batch addition method, a continuous addition method, a multistage addition method, or the like can be applied. Also, these addition methods may be combined as appropriate.

In the method for producing the polymer emulsion, it is preferable to neutralize the emulsion with a neutralizing agent after producing the emulsion by emulsion polymerization. This will stabilize the emulsion.
The neutralizing agent is not particularly limited, and for example, tertiary amines such as triethanolamine, dimethylethanolamine, diethylethanolamine and morpholine; diglycolamine, aqueous ammonia; sodium hydroxide and the like can be used. These may be used alone or in combination of two or more.

In the polymer cement mortar and polymer cement concrete used in the present invention, the blending ratio of the polymer emulsion is 0.25 to 25% by mass in terms of solid content with respect to 100% by mass of the total amount of the polymer cement mortar and polymer cement concrete. It is preferable to set More preferably 0.5 to 20 mass %, still more preferably 1.0 to 15 mass %. In addition, solid content can be measured as follows in this specification.
[Solid content measurement method]
1. Accurately weigh the aluminum dish.
2. Accurately weigh the solid content on the aluminum dish that was accurately weighed in 1.
3. The solid content measured accurately weighed in 2 is placed in a dryer controlled at 130° C. under a nitrogen atmosphere for 1.5 hours.
4. After 1 hour, remove from the dryer and allow to cool in a desiccator at room temperature for 15 minutes.
5. After 15 minutes, remove from the desiccator and accurately weigh the aluminum dish and the object to be measured.
The solid content is measured by subtracting the mass of the aluminum dish obtained in 1 from the mass obtained in 6.5 and dividing by the mass of the solid content measurement product obtained in 2.

<Cement, aggregate>
The cement used for the polymer cement mortar and polymer cement concrete is not particularly limited as long as it has hydraulic or latent hydraulic properties. Portland cement, silica cement, fly ash cement, blast furnace cement, alumina cement, belite-rich cement, various mixed cements; cements such as tricalcium silicate, dicalcium silicate, tricalcium aluminate, iron tetracalcium aluminate components; latent hydraulic fly ash, silica fume, slag, fine lime powder, and the like. These may be used alone or in combination of two or more. Among these, ordinary Portland cement is commonly used and can be suitably applied.

Aggregates used in the above polymer cement mortar and polymer cement concrete include sand, gravel, crushed stone, granulated slag, recycled aggregate, silica stone, clay, zircon, high alumina, silicon carbide, and graphite. Refractory aggregates such as iron, chromium, chromium, and magnesia can be used, and one or more of these can be used.

<Other additives>
The polymer cement mortar and polymer cement concrete used in the present invention may contain additives other than the (meth)acrylic polymer emulsion.
Other additives as used herein mean components other than the cement, water, aggregate, and the (meth)acrylic polymer emulsion contained in the polymer cement mortar and polymer cement concrete.

Other additives include commonly used cement dispersants and water reducing agents, water-soluble polymer substances, retarders, quick-setting agents, early strengthening agents/accelerators, mineral oil-based defoaming agents, oil-based defoaming agents, Fatty acid antifoaming agents, fatty acid ester antifoaming agents, oxyalkylene antifoaming agents, alcohol antifoaming agents, amide antifoaming agents, phosphate ester antifoaming agents, metal soap antifoaming agents, silicone antifoaming agents Foaming agents, AE agents, surfactants, waterproof agents, rust inhibitors, preservatives, crack reducing agents, expansive agents, cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers , self-leveling agents, coloring agents, anti-mold agents, blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, colloidal silica, fibers, gypsum, and other cement additives (materials). be done.

The cement dispersant (water reducing agent) is not particularly limited, and examples thereof include (i) polyalkylarylsulfonate-based dispersants such as naphthalenesulfonic acid formaldehyde condensates; melamine formalin resins such as melamine sulfonic acid formaldehyde condensates; Acid acid dispersant; aromatic aminosulfonate dispersant such as aminoarylsulfonic acid-phenol-formaldehyde condensate; ligninsulfonate dispersant such as ligninsulfonate and modified ligninsulfonate; polystyrene sulfone various sulfonic acid dispersants (water reducing agents) having a sulfonic acid group in the molecule, such as acid salt dispersants; Polyalkylene glycol mono (meth) acrylic acid ester monomers, (meth) acrylic acid monomers, and copolymers obtained from monomers copolymerizable with these monomers; JP-A-10- 236858, JP 2001-220417, JP 2002-121055, as described in JP 2002-121056, unsaturated (poly) alkylene glycol ether-based monomers, maleic acid-based monomers (iii) various polycarboxylic acid-based dispersants (water-reducing agents) having a (poly)oxyalkylene group and a carboxyl group in the molecule; As described in JP-A-2006-52381, (alkoxy) polyalkylene glycol mono (meth) acrylate, phosphoric acid monoester-based monomers, and copolymers obtained from phosphoric acid diester-based monomers, A copolymer having a (poly)oxyalkylene group and a phosphate ester group in the molecule; as described in JP-T-2008-517080, a (poly)oxyalkylene group and an aromatic and/or heterocyclic group A monomer having an aromatic group, a monomer having a phosphate (salt) group and/or a phosphate ester group and an aromatic ring group and/or a heterocyclic aromatic group, and a polymer consisting of an aldehyde compound Condensation products; dispersants having aromatic triazine structural units, polyalkylene glycol structural units, and phosphate ester structural units as described in JP-A-2015-508384; ) and the like.
Among these, polymer cement mortar and polymer cement concrete preferably further contain a water reducing agent. This further improves the adhesiveness of the paste to the aggregate.

The quick-setting agent is not particularly limited as long as it is a known quick-setting agent. The quick-setting agent to be used may be a powder quick-setting agent, a liquid quick-setting agent, or a slurry type quick-setting agent. Liquid quick-setting agents include, for example, aluminum sulfate, fluorine, alkali metals, and those containing these and alkanolamine, and one or more of these can be used. A known water-soluble hydration accelerator can be used as the liquid quick-setting agent used in the present invention. Examples of hydration accelerators include organic hydration accelerators such as formic acid or its salts, acetic acid or its salts, and lactic acid or its salts, water glass, nitrates, nitrites, thiosulfates, and thiocyanates. Inorganic hydration aids such as salts can be used. Examples of powder quick-setting agents include those containing calcium aluminates, sulfates, alkali metal aluminates, alkali metal carbonates, and oxycarboxylic acids, and one or two of these. The above can be used.

The antifoaming agent is not particularly limited as long as it is a known antifoaming agent. For example, mineral oil defoaming agents such as kerosene and liquid paraffin; oil defoaming agents such as animal and vegetable oils, sesame oil, castor oil and alkylene oxide adducts thereof; fatty acids such as oleic acid, stearic acid and alkylene oxide adducts thereof. antifoaming agents; diethylene glycol monolaurate, glycerin monoricinoleate, alkenylsuccinic acid derivatives, sorbitol monolaurate, sorbitol trioleate, polyoxyethylene monolaurate, polyoxyethylene sorbitol monolaurate, fatty acid esters such as natural waxes alcohol-based defoaming agents such as octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols and polyoxyalkylene glycol; amide-based defoaming agents such as polyoxyalkyleneamides and acrylate polyamines; tributyl phosphate, sodium Phosphate ester antifoaming agents such as octyl phosphate; metal soap antifoaming agents such as aluminum stearate and calcium oleate; foaming agents; oxyalkylene-based defoaming agents such as polyoxyethylene-polyoxypropylene adducts; and the like, and one or more of these can be used.

Among the antifoaming agents exemplified above, oxyalkylene antifoaming agents are most preferred. When the copolymer for cement admixture of the present invention and an oxyalkylene antifoaming agent are used in combination, the amount of the antifoaming agent used can be reduced, and the compatibility between the antifoaming agent and the copolymer is excellent. is. The oxyalkylene antifoaming agent is not particularly limited as long as it is a compound having an oxyalkylene group in the molecule and an action of reducing air bubbles in an aqueous liquid. Certain oxyalkylene antifoam agents are preferred.
R ¹ {-T-(R ² O) tR ³ }n (2)
In the above formula (2), R ¹ and R ³ are the same or different and are a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, an alkenyl group having 1 to 22 carbon atoms, an alkynyl group having 1 to 22 carbon atoms, a phenyl or an alkylphenyl group (the alkyl group in the alkylphenyl group has 1 to 22 carbon atoms). R ² O represents one type or a mixture of two or more types of oxyalkylene groups having 2 to 4 carbon atoms, and when two or more types are used, they may be added blockwise or randomly. t is the average number of added moles of the oxyalkylene group and represents a number from 0 to 300; When t is 0, R ¹ and R ³ are not hydrogen atoms at the same time, and T represents a group of -O-, -CO ₂ -, -SO ₄ -, -PO ₄ - or -NH-. n represents an integer of 1 or 2, and n is 1 when ^R1 is a hydrogen atom.

Examples of the oxyalkylene antifoaming agent represented by the above formula (2) include polyoxyalkylenes such as (poly)oxyethylene (poly)oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, poly Oxypropylene butyl ether, polyoxyethylene polyoxypropylene-2-ethylhexyl ether, (poly)oxyalkylene alkyl ethers such as oxyethyleneoxypropylene adducts to higher alcohols having 12 to 14 carbon atoms; polyoxypropylene phenyl ether, poly (Poly)oxyalkylene (alkyl)aryl ethers such as oxyethylene nonylphenyl ether; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne- Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as 2,5-diol and 3-methyl-1-butyn-3-ol; (Poly)oxyalkylene fatty acid esters; (poly)oxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan trioleate; polyoxypropylene methyl ether sodium sulfate, polyoxyethylene dodecylphenol (Poly) oxyalkylene alkyl (aryl) ether sulfates such as sodium ether sulfate; (poly) oxyalkylene alkyl phosphates such as (poly) oxyethylene stearyl phosphate; (poly) such as polyoxyethylene laurylamine ) oxyalkylenealkylamines; and the like, and one or more of these can be used.

In the polymer cement mortar and polymer cement concrete, the blending ratio of the water reducing agent is 0.01 to 1% by mass in terms of solid content with respect to 100% by mass of the total amount of the polymer cement mortar and polymer cement concrete. is preferred. It is more preferably 0.05 to 0.5% by mass, still more preferably 0.07 to 0.3% by mass.

In the polymer cement mortar and polymer cement concrete, the blending ratio of the antifoaming agent in terms of solid content is 0.01 to 1% by mass with respect to 100% by mass of the total amount of the polymer cement mortar and polymer cement concrete. is preferred. It is more preferably 0.05 to 0.5% by mass, still more preferably 0.07 to 0.3% by mass.

In the above polymer cement mortar and polymer cement concrete, the unit water amount per 1 m ³ , the amount of cement used, and the water/cement ratio are not particularly limited ^. /m ³ and a water/cement ratio (weight ratio) of 0.35 to 0.6. More preferably, the unit water amount is 140-240 kg/m ³ , the cement amount used is 350-480 kg/m ³ , and the water/cement ratio (weight ratio) is 0.4-0.5.

The aggregate/cement ratio (weight ratio) in the polymer cement mortar and polymer cement concrete is preferably 1 to 6 for polymer cement mortar. More preferably, it is 1-4. It is preferably between 1 and 10 for polymer cement concrete. More preferably, it is 2-8.

Concrete other than the polymer cement mortar and polymer cement concrete used in the member construction method of the present invention can be ordinary concrete, and is the same as the cement and aggregate used as raw materials for the polymer cement mortar and polymer cement concrete described above. The water/cement ratio and aggregate/cement ratio are the same as those of polymer cement mortar and polymer cement concrete.
Reinforcing bars generally used in the fields of civil engineering and construction can also be used for the reinforcing bars used in the member construction method of the present invention.

The construction method of the member of the present invention is a construction method that can construct a concrete structure excellent in wear resistance and durability while suppressing the cost, and is a construction method that can be constructed with good workability. However, the application is not limited to this, and can be similarly applied to dam discharge pipes and water intake pipes (especially where the cross section shrinks and the water pressure increases), and in addition to dams, agricultural waterways and other places where abrasion resistance is required. For example, it can be applied to bridge floor slabs, shield segments, steel shell blocks, building floor members, and the like.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited only to these examples. Unless otherwise specified, "part" means "part by weight" and "%" means "% by mass".

The Tg values of the homopolymers used for calculating the glass transition temperature (Tg) of the monomer components constituting the polymer, including those of the present examples, are shown below.
Methyl methacrylate: 105°C
Ethyl acrylate: -22°C
Acrylic acid: 95°C
Hydroxyethyl methacrylate: 55°C

<Average particle size>
The average particle size of the emulsion particles was measured using a particle size distribution analyzer (Otsuka Electronics Co., Ltd. FPAR-1000) based on the dynamic light scattering method.
<Solid content (N.V.)>
About 1 g of the obtained emulsion was weighed, dried in a hot air dryer at 150° C. for 1 hour, and the remaining amount after drying was defined as non-volatile matter, and the ratio to the weight before drying was expressed in mass %.

Synthesis example 1
1066 parts by weight of water, 14 parts by weight of polyoxyethylene nonylphenyl sulfate sodium salt, 1.5 parts by weight of an initiator, and the raw materials shown in Synthesis Example 1 in Table 1 were mixed in each weight part, and the mixture was heated at 75°C under a nitrogen atmosphere. Emulsion polymerization was carried out for 5 hours. After completion of the emulsion polymerization, 25% aqueous ammonia was added to adjust the pH to 9.8, and filtered through a 100-mesh wire mesh to obtain resin emulsion 1 for cement additives. Table 2 shows the glass transition temperature, polymer particle size, acid value and solid content of emulsion 1 obtained.

Synthesis Examples 2-5
Cement additive resin emulsions 2 to 5 were synthesized in the same manner as in Synthesis Example 1, except that the monomer ratio was changed to the following ratio. Table 2 shows the glass transition temperature, polymer particle size, acid value and solid content of emulsions 2 to 5 obtained.

Examples 1 to 5, Comparative Example 1
1. Preparation of Polymer Cement Mortar Using the cement additive resin emulsions 1 to 5 synthesized in Synthesis Examples 1 to 5, and blending as in Formulation Example 1, mortars of Test Examples 1 to 5 were prepared. The amount of emulsion added was adjusted so that the emulsion solid content was 20% by weight relative to the cement, and the amount of water added was adjusted so that the amount of water in the emulsion was 30% by weight relative to the cement. Also, as a blank, a mortar of Comparative Test Example 1 without addition of emulsion was prepared as in Formulation Example 2.
The operation for preparing the mortar was carried out according to the following method for preparing polymer cement mortar.
[Mortar Formulation Example 1]
C/S/W/P/defoaming agent 1/defoaming agent 2=780g/858g/234g/156g/3.1g/2.3g (W/C=0.3, S/C=1.1, P / C = 0.2, total antifoam / C = 0.007)
C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S: Silica Sand No. 7 (manufactured by Toyo Materan Co., Ltd.)
W: Total amount of pure water added and water contained in polymer emulsions synthesized in Synthesis Examples 1 to 5 P: Solid content of emulsion Antifoaming agent 1: MA-404 (manufactured by BASF Japan), for cement Defoamer 2: Nopco 8034L (manufactured by San Nopco), 0.3% by mass added to cement [Mortar Mixing Example 2]
C/S/W/Water reducer/Antifoamer = 780g/858g/234g/0.8g/3.1g
C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S: Silica Sand No. 7 (manufactured by Toyo Materan Co., Ltd.)
W: Added pure water amount water reducing agent: 0.1 mass% addition of polycarboxylic acid water reducing agent (manufactured by Nippon Shokubai) to cement Antifoaming agent: MA-404 (manufactured by BASF Japan Co., Ltd.) to cement 0 .4% by mass addition <Method for making polymer cement mortar>
In an environment where the temperature is 20°C ± 1°C and the relative humidity is 60% ± 10%, a stainless steel beater (stirring blade) is attached to a Hobart type mortar mixer (model number N-50; manufactured by Hobart), and C and S are added. It was put in and kneaded for 120 seconds at 1st speed. Next, ingredients other than C and S were added, and after kneading at 1st speed for 60 seconds, the mixer was stopped, the mortar was scraped off for 30 seconds, and kneading was further performed at 1st speed for 120 seconds to prepare mortar. .

2. Evaluation of Polymer Cement Mortar The polymer cement mortars of Test Examples 1 to 5 and Comparative Test Example 1 were evaluated as follows. Table 3 shows the results of 15-stroke flow value measurement and mortar air content measurement, and Table 4 shows the results of bending strength measurement.
<15 stroke flow value measurement>
Transfer the mortar from the kneading container to a polyethylene 1 L container, stir with a spatula 20 times, then immediately fill the flow cone (described in JIS R 5201-2015) placed on the flow measurement plate (30 cm × 30 cm) and fill it with half and 15 times. The flow cone was poked with a stick, and the mortar was filled up to the level of the flow cone. Immediately after that, the flow cone was lifted vertically and given 15 falling motions in 15 seconds, and then the 15-stroke flow of the mortar was measured, and this was taken as the 15-stroke flow value. Flow measurement was performed according to JIS R 5201-2015. It should be noted that the larger the flow value, the higher the dispersibility.
<Measurement of mortar air volume>
The mortar air content (initial air content) was measured by the method of JIS-A-1128 (revised in 2014). About 200 mL of the mortar was put into a 500 mL glass graduated cylinder, pierced with a round bar with a diameter of 8 mm, and gently vibrated by hand to remove coarse air bubbles. Further, about 200 mL of mortar was added and air bubbles were removed in the same manner, and then the volume and mass of the mortar were measured, and the amount of air was calculated from the density of each material.
<Bending strength measurement>
(1) Creation of bending strength test piece The test piece (4 × 4 × 16 cm) used for bending strength is prepared according to the above-mentioned <Method for making polymer cement mortar>, using kneaded mortar, conforming to JIS A 1171-2016. It was carried out according to the described method.
In other words, the prepared polymer cement mortar is packed in two layers in a mold of 4×4×16 cm and molded. The polymer cement was filled to about half of the height of the mold, and the entire surface was poked with a ram. Next, the polymer cement was filled up to the upper end of the mold, and the whole surface was poked with a ram. Finally, after flattening the surface, the container was sealed and stored at 20° C. for initial curing (sealed curing). After one day, the mold was removed and then cured to prepare a bending strength test piece. Curing was carried out at 20°C for 28 days in the case of room temperature curing, and in the case of steam curing, curing was carried out at 90°C for 48 hours and then at 20°C for 25 days. In the case of dry curing, after curing at 90°C for 48 hours, curing at 100°C for 24 hours, and then curing at 20°C for 24 days.
(2) Measurement of flexural strength Using the flexural strength specimen prepared in (1) above, flexural strength was measured according to the method described in JIS R 5201-2015. The strength tester used was a fully automatic pressure resistance tester (TYPE: ACA-50S-B2, manufactured by Mayekawa Test Instruments Co., Ltd.), and the test was conducted with a dedicated bending strength jig installed.

Example 6, Comparative Examples 2-4
1. Preparation of Polymer Cement Concrete Concrete of Test Example 6 was prepared by blending as in Formulation Example 1 using Resin Emulsion 2 for cement additives synthesized in Synthesis Example 2. The added amount of emulsion was adjusted so that the emulsion solid content was 20% by weight relative to the cement, and the amount of water added was adjusted so that the amount of water in the emulsion was 55% by weight relative to the cement. In addition, as a blank, concrete of Comparative Test Example 2 to which no emulsion was added was prepared as in Formulation Example 2.
[Concrete Formulation Example 1]
W/C/S coarse/S fine/G large/G small/admixture/P/admixture 1/admixture 2=
2.306kg/9.00kg/21.55kg/4.70kg/16.51kg/11.95kg/0.51kg/4.444kg/4.5g/18.0g
(W / C = 0.55, P / C = 0.2, total antifoam / C = 0.005)
W: Total amount of pure water added and water contained in the polymer emulsion synthesized in Synthesis Example 2 C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S Coarse: Crushed sand from Miyama, Hachioji S Fine: Mountain sand from Yoshino, Kimitsu City, Chiba Prefecture
G-large: Coarse aggregate from Ome, Tokyo G-small: Coarse aggregate from Ome, Tokyo Admixture: Sepiolite (manufactured by Tomoe Kogyo Co., Ltd.)
P: Solid content of emulsion Admixture 1: Antifoaming agent, alcohol-based antifoaming agent (manufactured by Frolic)
Admixture 2: AE agent, AE-4 (manufactured by Flolic)
[Concrete Formulation Example 2]
W/C/S Coarse/S Fine/G Large/G Small/Admixture 2/Admixture 3=
4.950kg/9.00kg/21.55kg/4.70kg/16.51kg/11.95kg/23.4g/85.5g
(W / C = 0.55, total antifoam / C = 0.005)
W: Amount of pure water added C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S Coarse: Crushed sand, Miyama, Hachioji S Fine: Mountain sand, Yoshino, Kimitsu City, Chiba Prefecture G Large: Coarse Aggregate, Ome, Tokyo G Small: Coarse Aggregate, Ome, Tokyo Admixture 2: AE agent, AE -4 (manufactured by Floric)
Admixture 3: AE water reducing agent, SV10 (manufactured by Flolic)
<Method for making polymer cement concrete>
A 50-liter forced twin-screw mixer was used, and the kneading amount was 30 liters. First, materials other than W, P, and admixtures 1 and 2 were added and kneaded for 30 seconds. Next, all materials were put in and mixed for 30 seconds, then the mixer was stopped, the concrete was scraped off for 30 seconds, and then mixed for another 60 seconds to prepare concrete.

2. Concrete Strength Test Using the polymer cement concrete of Test Example 6 and Comparative Test Example 2, the following strength tests were carried out.
(1) Preparation of strength test specimens Polymer cement concrete was placed in a summit mold of φ100 x 200 mm and a formwork of □ 100 x 100 x 400 mm. One was subjected to normal temperature curing as described below, and the other was subjected to dry curing.
Normal temperature curing: Curing for 28 days at 20°C and 80% humidity.
Dry curing: After curing for 2 days at 20° C. and 80% humidity, curing is performed for 2 days at 90° C. and 80% humidity, and further drying curing is performed at 100° C. for 3 days.
(2) Compressive strength test The compressive strength of the specimen after curing was measured according to JIS A 1108. Table 5 shows the results.
(3) Splitting tensile strength test After curing, the splitting tensile strength was measured according to JIS A 1113. Table 5 shows the results.
(4) Bending strength test The bending strength of the specimen after curing was measured according to JIS A 1106. Table 5 shows the results.

Example 7, Comparative Examples 5-7, Reference Examples 1-2
1. Preparation of Polymer Cement Concrete Concrete of Test Example 7 was prepared by mixing Resin Emulsion 2 for Cement Additive Synthesized in Synthesis Example 2 as described in Formulation Example 3. The added amount of emulsion was adjusted so that the emulsion solid content was 49% by weight relative to the cement, and the amount of water added was adjusted so that the amount of water in the emulsion was 26% by weight relative to the cement. In addition, as a blank, a concrete of Comparative Test Example 3 without addition of emulsion was prepared as in Formulation Example 4.
[Concrete Formulation Example 3]
W/C/S coarse/S fine/G large/G small/admixture/P/admixture 1/admixture 2=
2.306kg/9.00kg/21.55kg/4.70kg/16.51kg/11.95kg/0.51kg/4.444kg/4.5g/18.0g
(W/C=0.26, P/C=0.49, Defoamer/C=0.0005)
W: Total amount of tap water added and water contained in the polymer emulsion synthesized in Synthesis Example 2 C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S Coarse: Crushed sand, Miyama, Hachioji S Fine: Mountain sand, Yoshino, Kimitsu City, Chiba G Large: Coarse Aggregate, Ome, Tokyo G Small: Coarse Aggregate, Ome, Tokyo Admixture: Sepiolite (Tomoe Kogyo Co., Ltd.) made)
P: Resin emulsion 2 for cement additives synthesized in Synthesis Example 2
Admixture 1: antifoaming agent, alcohol-based antifoaming agent (manufactured by Flolic)
Admixture 2: AE agent, AE-4 (manufactured by Flolic)
[Concrete Formulation Example 4]
W/C/S Coarse/S Fine/G Large/G Small/Admixture 2/Admixture 3=
4.950kg/9.00kg/21.55kg/4.70kg/16.51kg/11.95kg/23.4g/85.5g
(W / C = 0.55, total antifoam / C = 0.005)
W: Amount of pure water added C: Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.)
S Coarse: Crushed sand, Miyama, Hachioji S Fine: Mountain sand, Yoshino, Kimitsu City, Chiba Prefecture G Large: Coarse Aggregate, Ome, Tokyo G Small: Coarse Aggregate, Ome, Tokyo Admixture 2: AE agent, AE -4 (manufactured by Floric)
Admixture 3: AE water reducing agent, SV10 (manufactured by Floric)
<Method for making polymer cement concrete>
A 50-liter forced twin-screw mixer was used, and the kneading amount was 30 liters. First, materials other than W, P, and admixtures 1 and 2 were added and kneaded for 30 seconds. Next, all materials were put in and mixed for 30 seconds, then the mixer was stopped, the concrete was scraped off for 30 seconds, and then mixed for another 60 seconds to prepare concrete.

2. Abrasion resistance strength test The polymer cement concrete of Test Example 7 and Comparative Test Example 3 were subjected to the following abrasion resistance evaluation.
(1) Abrasion resistance test Specimen preparation A steel box having an inner surface width of 143 mm, a length of 297 mm, and a thickness of 32.5 mm was filled with polymer cement concrete, allowed to stand at 20°C for 24 hours, and demolded. Two specimens were prepared, one of which was subjected to normal temperature curing and the other of which was subjected to dry curing.
Normal temperature curing: Curing for 28 days at 20°C and 80% humidity.
Dry curing: Raise the temperature to 90°C at 15°C/hour, cure for 48 hours at 90°C and 80% humidity, lower the temperature at 5°C/hour to 20°C, and then dry in a drying oven at 100°C for 24 hours. Take care of yourself.
(2) Abrasion resistance test Okuda's abrasion resistance test, which was devised as a prototype at the Central Research Institute of Electric Power Industry, was adopted to confirm the presence or absence of polymers and differences in curing methods. The test method is to set the specimen prepared as described above in a rotating drum in which a carbon steel Silpep is inserted, and shower about 5 L / min of water from the pipe in the center of the test machine. The test was performed by rotating the rotary drum at a rotation speed of , and the abrasion coefficient was calculated 4 hours after the start of the test. For reference, the abrasion test was performed using the long-life concrete (registered trademark: EIEN, the formulation is described in JP-A-2006-182583) described in Patent Document 7 above, and accelerated neutralization of 5% CO ₂ Using a specimen left still in a tank (20 ° C., humidity 60%) until the age of 28 days, and ultra-high strength fiber reinforced concrete (registered trademark: Succem) described in Patent Document 3, 85 ° C., humidity 80% It was also carried out on a specimen prepared by steam curing for 24 hours at . The results are shown in Table 6 and FIG. A smaller abrasion coefficient means better resistance to abrasion.

From the results shown in Tables 2 to 6 and FIG. 11, the polymer cement mortar and polymer cement concrete used in the present invention have high strength and abrasion resistance equivalent to EIEN and Succem. was also confirmed to be excellent. Therefore, by using these on the member surface, a structural member having excellent strength and abrasion resistance can be constructed.
Although EIEN and SUQCEM are also excellent in abrasion resistance, they are more expensive than the polymer cement mortar and polymer cement concrete used in the present invention, and require special curing and special materials. Therefore, the versatility of the present invention, which can be produced with the same composition as ordinary concrete, is high.

1: Rebar 2: Ordinary concrete 3: Polymer cement mortar/concrete 4: Vibrator
5: formwork 6: partition member 7: embedded formwork

Claims (5)

A method of constructing a member, wherein a portion of the member is constructed from a material comprising polymer cement, comprising:
a reinforcing bar assembly process for constructing reinforcing bars to be placed inside the member;
a concrete placing step of placing concrete in an area excluding at least a part of the surface layer of the member surface;
a polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete in the surface layer where no concrete was placed in the concrete placing step;
and a heating step of heating the member after placing the polymer cement mortar or polymer cement concrete at a temperature higher than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C. The construction method of the member to be. A method of constructing a member, wherein a portion of the member is constructed from a material comprising polymer cement, comprising:
a polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete on at least a partial surface layer of the surface of the member;
a heating step of heating the surface layer portion on which the polymer cement mortar or polymer cement concrete is placed at a temperature higher than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100 ° C.;
a reinforcing bar assembly process for constructing reinforcing bars to be placed inside the member;
A method of constructing a member, comprising: a step of placing concrete in a region other than the surface layer portion. A method of constructing a member, wherein a portion of the member is constructed from a material comprising polymer cement, comprising:
an embedded formwork installation step of arranging an embedded formwork having a layer of polymer cement mortar or polymer cement concrete on at least part of the outside;
a reinforcing bar assembling step of constructing reinforcing bars inside the embedded formwork;
and a concrete placing step of placing concrete inside the embedded formwork,
The embedded formwork is constructed through a heating step of heating a polymer cement mortar or polymer cement concrete layer at a temperature higher than the glass transition temperature of the polymer used in the polymer cement and at a temperature of 40 to 100 ° C. A construction method for a member, characterized in that it is a material. The member construction method according to any one of claims 1 to 3, wherein the heating step is performed at a temperature of 50 to 100°C. 5. The member construction method according to claim 1, wherein the polymer used for the polymer cement has a glass transition temperature of 35 to 100.degree.

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