JP2020111897A - Construction method of component - Google Patents

Abstract

To provide a construction method of a component with excellent abrasion resistance capable of constructing a concrete structure with excellent workability and cost.SOLUTION: Method of constructing a member by constructing a part of the member with polymer cement, includes: a reinforcing bar assembly process to construct reinforcing bar 1 placed inside the member; assembling reinforcing bar; a concrete supplying process of supplying concrete 2 in an area except for at least part of the surface layer of the member surface; a polymer cement mortar/concrete placing process in which polymer cement mortar or polymer cement concrete 3 is placed on the surface layer where concrete 2 is not placed in the concrete placing process; and a heating process in which the member after placing the polymer cement mortar or polymer cement concrete 3 is heated to a temperature above the glass transition temperature of the polymer used in the polymer cement, which is a temperature of 40 to 100°C.SELECTED DRAWING: Figure 2

Description

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

Concrete, whose shape can be freely designed and which has high durability, 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 is a demand for further strength improvement, and of the concrete structures that have passed the age of construction, a method of repairing the most easily deteriorated surface layer cross section called the cover part or a method of strengthening the cover part Therefore, various methods have been studied conventionally. As a conventional method for increasing the tensile strength of the cover of a concrete structure, a method of reinforcing the surface of an existing concrete structure with carbon fibers or reinforcing bars having a predetermined diameter (see Patent Documents 1 and 2) and reinforcing fibers are used. High strength fiber reinforced concrete including concrete is known (see Patent Documents 3 and 4). In addition, as a method of repairing a concrete structure, a method of repairing a concrete structure with a polymer cement mortar using a polymer having a predetermined glass transition temperature, or after removing the surface concrete of an irrigation canal whose surface is deteriorated, 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 restoration material containing a special non-hydraulic compound, and then carbonating the surface after the cross-section restoration material is hardened, etc. Are known (see Patent Documents 5 to 7).

Among these concrete structures, one of the concrete structures that require strength of the cover is as a countermeasure against physical deterioration (countermeasure against cross-section reduction) is an agricultural canal or a dam. Agricultural waterways are required to have abrasion resistance and strength because not only water but also sand and driftwood may collide. Further, the dam is provided with a discharge facility for discharging excess water, and in particular, a spillway is provided for the purpose of ensuring the safety of the dam during a flood. Since the energy of the water discharged from the dam during flooding is very large, the spillway is equipped with a dampener to control the water flow. The energy of this large amount of water is added to the energy-reducing work, and driftwood or boulders flowing from the upstream side may collide with the muddy flow, so if the surface of the energy-reducing work is ordinary concrete, the energy will be reduced during discharge. The barrage is damaged and the cross section decreases over the years. Therefore, a material having high abrasion resistance is required for the surface of the concrete forming the energy-reducing structure, and conventionally, the surface of the energy-reducing structure is covered with a steel plate or the like. As for dams, as a method of increasing the wear resistance of dam dams, a construction method is known in which a reinforcing rail with detachably connected legs is laid on an inclined waterfall and high-strength concrete is poured ( Patent document 8).

JP, 2001-32532, A JP, 2003-35041, A JP, 2017-110399, A JP, 2018-91063, A JP, 2006-124232, A JP, 2011-148695, A JP, 2007-22878, A JP-A-2002-69981

According to the Agricultural Civil Engineering Business Association, the concrete applied to agricultural canals has a wear depth specified in a water sand jet wear test after 10 hours when compared with a standard test body by JIS mortar. It is set as a condition that it is 5 or less. The existing ultra-high strength fiber reinforced concrete is 0.32 when JIS mortar is standard. As a result of the Okuda-type abrasion test after 4 hours devised by the Central Research Institute of Electric Power Industry, the abrasion coefficient of the ultra-high strength fiber reinforced concrete is about 250 mm ³ /cm ² .
In the case where such a portion that is particularly required to have abrasion resistance is to have a concrete structure, by applying the super-high strength fiber reinforced concrete described in Patent Documents 3 and 4 or the carbonation curing described in Patent Document 7, It is conceivable to apply long-life concrete that is made by densifying hardened surface concrete cement. However, ultra-high-strength fiber-reinforced concrete requires special fiber materials and concrete blending, and long-life concrete requires special equipment for carbonation curing in addition to using the special admixture γ-C ₂ S. Therefore, not only the labor of construction but also the cost is disadvantageous, and the adoption thereof is difficult. For this reason, there is a demand for a method capable of constructing a concrete structure that is superior in workability and cost and is excellent in scuff resistance.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a construction method capable of constructing a concrete structure excellent in workability and cost and excellent in abrasion resistance.

The present inventor has studied the construction method which is excellent in workability and cost, and is capable of constructing a concrete structure excellent in abrasion resistance, constructs a reinforcing bar arranged inside a member, and at least a part of the member surface. After placing concrete in the area excluding the surface layer part, the concrete cement mortar or polymer cement concrete is placed on the surface part where concrete was not placed in the concrete placing process, and then that member is used as polymer cement When the member is constructed by the process of heating at a temperature not lower than the glass transition temperature of the polymer and at a temperature of 40 to 100° C., abrasion resistance and freeze-thaw while suppressing the amount of polymer concrete, which is more expensive than ordinary concrete, are suppressed. It has been found that a concrete structure having excellent resistance can be constructed. The present inventor further pour polymer cement concrete, the step of heating, and the step of constructing a reinforcing bar arranged inside the member, and pouring concrete in a region excluding at least a part of the surface layer of the member surface, It was found that it is possible to construct a concrete structure excellent in both abrasion resistance and freeze-thaw resistance in the same manner even in a construction method in which the order of the above is changed or in a construction method using an embedded formwork, and the present invention has been achieved. is there.

That is, the present invention is a method for constructing a member in which a part of the member is constructed of a material made of polymer cement, and a reinforcing bar assembling step for constructing a reinforcing bar arranged inside the member, and at least a part of the surface layer part of the member surface. Concrete placing step of placing concrete in the area excluding the area, and 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 not lower than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100°C. Is a construction method of members.

The present invention also relates to a method of constructing a member in which a part of the member is constructed from a material made of polymer cement, wherein polymer cement mortar or polymer cement mortar is cast on at least a part of the surface layer of the member surface. / Concrete placing step and heating for heating the polymer cement mortar or the surface layer portion on which polymer cement concrete is placed at a temperature not lower than the glass transition temperature of the polymer used for polymer cement and at a temperature of 40 to 100°C The method for constructing a member is also characterized by including a step, a reinforcing bar assembling step of constructing a reinforcing bar arranged inside the member, and a concrete placing step of placing concrete in a region excluding the surface layer portion.

The present invention further relates to a method for constructing a member, wherein a part of the member is constructed of a material made of polymer cement, wherein an embedded mold having a polymer cement mortar or polymer cement concrete layer on at least a part of the outside is disposed. A frame installation step, a rebar assembly step of constructing a reinforcing bar inside the buried formwork, and a concrete placing step of placing concrete inside the buried formwork, wherein the buried formwork is a polymer cement mortar or a polymer. Construction of a member characterized by being constructed through a heating step of heating a cement concrete layer at a temperature not lower than the glass transition temperature of the polymer used for 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 for the polymer cement preferably has a glass transition temperature of 35 to 100°C.

Since the construction method of the member of the present invention is a construction method capable of constructing a concrete structure excellent in scuff resistance with good workability while suppressing cost, it can be used for construction of various concrete structures. Above all, it can be suitably used for construction of a surface of an irrigation canal for dams for spillage of dams for which abrasion resistance is required, a surface layer of the outer shell of a gravity dam dam body, and the like.

It is a figure showing an example of an embodiment of the 1st construction method of the present invention. It is a figure showing an example of an embodiment of the 1st construction method of the present invention. It is a figure showing an example of an embodiment of the 1st construction method of the present invention. It is a figure showing an example of an embodiment of the 1st construction method of the present 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 a figure showing an example of an embodiment of the 3rd construction method of the present invention. It is a figure showing an example of an embodiment of the 3rd construction method of the present invention. It is a figure showing an example of an embodiment of the 3rd construction method of the present invention. It is a figure showing an example of an embodiment of the 3rd construction method of the present invention. It is the figure which showed the result of abrasion resistance evaluation of Example 7, Comparative Examples 5-7, and Reference Examples 1-2.

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

The construction method of the member of the present invention is characterized by using polymer cement mortar/concrete. Polymer cement mortar/concrete does not require special curing, can be placed on site and does not require special equipment. In terms of cost, there is an advantage that it is possible to provide a concrete having the same abrasion resistance at a lower cost than the above-mentioned ultra-high-strength fiber reinforced concrete and extended life concrete. Furthermore, in the construction method of the member of the present invention, the cost is further reduced by forming the surface layer of the member, which is required to have high abrasion resistance, with polymer cement mortar/concrete, and forming the other members inside with normal concrete. Has been realized.
The member construction method of the present invention is also applied to the surface layer of a structure applied to cold regions. For example, it is an outer shell portion of a gravity dam dam body constructed in a cold area such as a mountain area. High freeze-thaw resistance is required in such places, and according to JIS A 1148 "Test method for freeze-thaw of concrete", a condition of relative dynamic elastic modulus of 60% or more is set in a freeze-thaw test of 300 cycles. ing.
The structural member/structure having the polymer cement mortar/concrete layer on the surface layer, which is constructed by the construction method of the present invention, has high freeze-thaw resistance in addition to high abrasion resistance. That is, it has the performance which satisfies the above-mentioned technical standard, which defines the freeze-thaw resistance of the concrete structure.
Application of polymer cement mortar/concrete to the surface layer structure of concrete, which is required to have high abrasion resistance and high freeze-thaw resistance, has not been known in the past.
The inventors of the present invention have focused their attention on such high durability performance of polymer cement mortar/concrete, and have carried out diligent research and development, and the performance capable of solving the problems of the present invention is secured by experiments and the like assuming actual application described later. We are confirming that.

There are the following three construction methods for constructing the member of the present invention.
(1) A concrete reinforcement step is included, including a rebar assembling step for constructing a rebar to be arranged inside the member, and a concrete pouring step for pouring concrete in an area of at least a part of the surface layer of the member surface. A method in which polymer cement mortar or polymer cement concrete is placed on the surface layer in which the cast was not placed and heated at a predetermined temperature (hereinafter referred to as the first method of the present invention)
(2) A step of placing polymer cement mortar or polymer cement concrete on at least a part of the surface layer portion of the member surface, and a step of heating the surface layer portion on which the polymer cement mortar or polymer cement concrete is placed at a predetermined temperature. , A reinforcing rod assembling step, and further performing a concrete placing step of placing concrete in an area excluding a surface layer portion where polymer cement mortar or polymer cement concrete is placed (hereinafter, referred to as a second method of the present invention and (Statement)
(3) An embedded mold in which an embedded formwork having a polymer cement mortar or a polymer cement concrete layer, which is constructed through a heating step of heating the polymer cement mortar or the polymer cement concrete layer at a predetermined temperature, is arranged at least on a part of the outer side. A method of performing a frame installation step, a reinforcing bar assembly step of constructing a reinforcing bar inside the buried formwork, and a concrete placing step of placing concrete inside the buried formwork (hereinafter referred to as the third construction 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 member of the present invention will be described.

1. The first construction method of the present invention is the first construction method of the present invention, in which concrete other than the surface layer portion on which polymer cement mortar or polymer cement concrete is placed is first cast, and then the polymer is applied to at least a part of the surface layer portion. It is a construction method in which cement mortar or polymer cement concrete is placed and heated at a predetermined temperature, and the inside is placed in advance.
1 and 2 are views showing one of the embodiments in the case of constructing a floor slab, a water conduit, etc. in a cold region 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 for constructing a reinforcing bar 1 inside a member and a concrete pouring step for pouring concrete 2 in an area excluding at least a part of the surface layer of the member surface are performed. Be seen. In FIG. 1, a reinforcing bar 1 arranged inside a member is assembled, and concrete 2 is poured while leaving a part of the upper part of the reinforcing bar. In the concrete pouring process, ordinary concrete is poured.

In the first construction method of the present invention, before the concrete pouring step, a partition member is installed by partitioning the surface layer portion into which the polymer cement mortar or polymer cement concrete is placed and the area excluding the surface layer portion by arranging a partition member. It is preferred to perform the steps. By performing the partitioning member installation process, ensure the separation of the surface layer part where polymer cement mortar/concrete is placed and the other part, and ensure the surface part where polymer cement mortar or polymer cement concrete is placed later. Can be secured.

Next, a polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete 3 on the surface layer where concrete 2 is not placed is carried out, and thereafter, the glass transition temperature of the polymer used for the polymer cement or higher. And a heating step of heating at a temperature of 40 to 100°C. After heating, it is desirable to cure the member in air or dry. Here, the aerial curing is a curing method of curing in the state of being exposed to the air without giving moisture, and the dry curing is a process of aerial curing, in which temperature history or the like is given to actively dry. A curing method that includes steps.
In FIG. 2, polymer cement mortar or polymer cement concrete 3 is cast in the surface layer portion including the upper portion of the reinforcing bar 1 where the ordinary concrete 2 was not cast. The reinforcing bar in the surface layer part may be constructed integrally with the reinforcing bar of the lower reinforced concrete, or may be a reinforcing bar connected to a reinforcing bar projecting 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 integrate the ordinary concrete placed earlier. By this operation, the ordinary concrete 2 and the polymer cement mortar/concrete 3 are sufficiently integrated.
After such a polymer cement mortar/concrete casting step, a compaction integration step of compacting and integrating the concrete placing section and the polymer cement mortar/concrete placing section by vibration with a vibrator is included. 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, a polymer cement mortar/concrete kneading step of kneading polymer cement mortar/concrete by post-adding a polymer to an agitator vehicle is performed before the polymer cement mortar/concrete placing step. Is preferred. By doing so, it becomes possible to manufacture polymer cement mortar/concrete without installing special equipment in the plant.

After the polymer cement mortar/concrete placing step and before the heating step, it is preferable to perform a compacting and finishing step for the surface layer portion. This step can be carried out by a tamper or a leveling machine for trowel finishing.
Further, it is preferable to perform a wet curing step after the polymer cement mortar/concrete placing step and before a heating step. As a result, the hydration reaction of the cement in the concrete is promoted, and the concrete becomes highly durable. The wet curing can be performed by flooding curing or sheet curing, and the period of wet curing 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 a temperature not lower than the glass transition temperature of the polymer used for the polymer cement and is heated at a temperature of 40 to 100° C., for example, in the surface layer portion. It can be performed by arranging a heater such as a jet heater or a film heater and heating the surface layer portion. If the area to be heated is small, heat may be supplied by the eye lamp.
The heating in the heating step may be performed 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., but 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 cure the member in air or dry.

As another embodiment of the first construction method of the present invention, a case of constructing a wall portion such as a water channel is shown in FIGS.
In this embodiment, first, the mold 5 is arranged, and a reinforcing bar assembling step of assembling the reinforcing bar 1 in the mold is performed. At that time, the partition member 6 is disposed at the boundary between the wall portion which is the end portion and the region on the central portion side. As the partition member, a lath net, an air tube, a concrete splice stop comb, or the like can be used as the partition member embedded in the mold. The partition member 6 is fixed to the reinforcing bar 1 by inserting the reinforcing bar 1 (the horizontal reinforcing bar in the drawing). In this state, a concrete pouring step is performed in which the ordinary concrete 2 is poured on the central side (FIG. 3).

Next, a polymer cement mortar/concrete placing step is performed in which polymer cement mortar/concrete 3 is placed on the end wall (FIG. 4). After the polymer cement mortar/concrete placing step, it is preferable to carry out the compacting and integrating step using the above-mentioned vibrator in order to integrate the ordinary concrete 2 that has been placed earlier.

After the concrete exhibits a predetermined demolding strength (about 5 N/mm ² ) by a hydration reaction, a demolding step of demolding the mold is performed. The period until the demolding step is performed is not particularly limited as long as it exhibits a predetermined demolding strength, but in the case of ordinary concrete, it can be demolded within 2 to 4 days after pouring, for example. ..

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

2. Second Construction Method of the Present Invention In the second construction method of the present invention, the polymer cement mortar or the polymer cement concrete is first cast into at least a part of the surface layer portion of the member, and then the other is performed after heating at a predetermined temperature. This is a method of placing concrete in the area of, and placing the outside first.
5 and 6 are views showing one of the embodiments in the case of constructing a member by the second construction method of the present invention. This embodiment is an embodiment in which polymer cement mortar or polymer cement concrete is placed in advance only on the outer surface of the wall member or the plate (slab) member. The second construction method will be described with reference to these drawings.
In this embodiment, first, the formwork 5 is arranged, and the reinforcing bars 1 are assembled in the formwork. At that time, the partition member 6 is arranged at the boundary between the outer wall surface portion on the outer side (left side in FIG. 5) and the central region. As the partition member, a lath net, an air tube, a concrete splice stop comb, or the like can be used as the partition member embedded in the mold. The partition member 6 is fixed to the distribution bar (reinforcing bar perpendicular to the plane of FIG. 5).

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

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

After that, a step of placing ordinary concrete on the center side of the wall and the upper side of the slab is performed (FIG. 6).
At this time, in order to integrate the polymer cement concrete or polymer cement mortar on the outer surface portion with the ordinary concrete on the inner side, it is preferable to insert a vibrator at the boundary portion for vibration compaction. The vibration compaction can be performed by the method described above.
That is, also in the second construction method of the present invention, after the ordinary concrete placing step, the compacting and integrating step of integrating the polymer cement mortar/concrete placing section and the concrete placing section by vibration with a vibrator is performed. That is the preferred embodiment.

Then, after the concrete exhibits a predetermined demolding strength (about 5 N/mm ² ) by a hydration reaction, a demolding step of demolding the mold is performed. The period until the demolding step is performed is not particularly limited as long as it exhibits a predetermined demolding strength, but in the case of ordinary concrete, it can be demolded within 2 to 4 days after pouring, for example. ..

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

3. Third Construction Method of the Present Invention A third construction method of the present invention is to arrange an embedded formwork having a polymer cement mortar or polymer cement concrete layer heated at a predetermined temperature in at least a part of the outside, and to arrange the inside of the embedded formwork. It is a construction method of placing concrete in.
7 and 8 are views showing one of the embodiments for constructing a member by the third 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 a gutter-shaped member, a culvert, and a plate (slab) member forming a water channel. The third construction method will be described with reference to these drawings.
In the third construction method, an embedded formwork 7 having a polymer cement mortar or polymer cement concrete layer heated at a predetermined temperature on at least a part of the outside is used.

The embedded formwork is a polymer cement mortar or polymer cement concrete is placed in advance in part or all of the formwork for making the embedded formwork, and the temperature is not less than the glass transition temperature of the polymer used for the polymer cement, and It can be manufactured by heating at a temperature of 40 to 100° C. and then demolding. An embedded formwork in which only a part of the embedded formwork was formed by polymer cement mortar or polymer cement concrete layer was partitioned by placing a partition member in the formwork for making the embedded formwork. It can be made by placing polymer cement mortar or polymer cement concrete in a part of the mold and placing ordinary concrete in the other part.
The buried formwork is preferably steam cured at a precast plant where the buried formwork is made. At that time, since the strength improving effect is exerted by giving a higher temperature history, it is preferable to perform the curing at the highest temperature in the possible range of the steam curing tank of the precast factory. After steam curing, it is desirable that the member be cured in air or dry. When the buried formwork is produced, the polymer emulsion mortar/concrete can be produced in the same process as the ordinary concrete production process by putting the polymer emulsion in the tank of the admixture of the plant.

In the embodiment of FIG. 7, an embedded formwork 7 having a polymer cement mortar/concrete layer heated at a predetermined temperature on at least a part of its outer side is arranged, and the reinforcing bar 1 is assembled in the formwork. After that, the formwork 5 is arranged and ordinary concrete is placed between the buried formwork 7 and the formwork 5 (FIG. 8).

Then, after the concrete exhibits a predetermined demolding strength (about 5 N/mm ² ) by a hydration reaction, a demolding step of demolding the mold is performed. The period until the demolding step is performed is not particularly limited as long as it exhibits a predetermined demolding strength, but in the case of ordinary concrete, it can be demolded within 2 to 4 days after pouring, for example. ..

9 and 10 are views showing another embodiment in the case of constructing a member by the third construction method of the present invention. 9 and 10 show an embodiment in which an embedded formwork made of polymer cement mortar/concrete is constructed so as to serve as a surface layer of a floor slab of a highway or the like.
In the embodiment of FIG. 9, the embedded formwork 7 and the formwork 5 having the polymer cement mortar/concrete layer on at least a part of the outer side are arranged downward, and the rebar 1 is assembled inside. Then, ordinary concrete 2 is placed inside the mold, and after the concrete exhibits a predetermined demolding strength (about 5 N/mm ² ) due to a hydration reaction, it is inverted (FIG. 10) and the mold is demolded. ..

4. Materials Used for Construction Method of Member of the Present Invention Next, materials used for construction method of the member 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 materials of cement mortar and cement concrete and kneading them. By using such polymer cement mortar and polymer cement concrete, the structure constructed by the construction method of the member of the present invention becomes excellent in abrasion resistance and also excellent in strength. ..
The polymer preferably has a glass transition temperature (Tg) of 35 to 100°C. When such a polymer having Tg is used, the polymer cement mortar and the polymer cement concrete have higher strength and excellent abrasion resistance. The Tg of the polymer is more preferably 35 to 90°C, further preferably 35 to 70°C, particularly preferably 35 to 60°C, and most preferably 35 to 50°C.
The glass transition temperature (Tg) of the polymer can be controlled by the kind and the ratio of use of the monomer component as a raw material of the polymer, and can be determined by the following FOX equation (1), and DSC (differential scanning). It can be determined by a calorimeter or DTA (differential thermal analyzer).

In the formula, Tg' is the Tg (absolute temperature) of the copolymer emulsion particles. W1', W2',... Wn' are mass fractions of the respective monomers with respect to the total monomer components. Tgn, Tg2,... Tgn are glass transition temperatures (absolute temperatures) of homopolymers (homopolymers) composed of the respective monomer components. As the glass transition temperature of the homopolymer used in the above calculation, the value described in the literature can be used, and for example, it is described in “POLYMER HANDBOOK 3rd edition” (published by John Wiley & Sons, Inc.). ..

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

The polymer is preferably in the emulsion form. The polymer emulsion may contain one type of polymer or may contain two or more types of polymers. Further, the polymer emulsion preferably contains a polymer having a monomer unit having a carboxylic acid (salt) group. The carboxylic acid (salt) group means a carboxylic acid group and/or a carboxylic acid group.
Preferred examples of the carboxylate group salt include metal salts, ammonium salts, organic amine salts and the like. Examples of the metal atom forming the metal salt include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; divalent metal atoms such as calcium and magnesium; trivalent metals such as aluminum and iron. Atoms are more preferred. Further, as the organic amine salt, an alkanolamine salt such as an ethanolamine salt, a diethanolamine salt and a triethanolamine salt, and an alkylamine salt such as a triethylamine salt are more preferable.

As the monomer having a carboxylic acid (salt) group, a (meth)acrylic acid (salt) type monomer is preferable. The (meth)acrylic acid (salt)-based monomer has at least one group of an acryloyl group or a methacryloyl group, or a group in which a hydrogen atom in these groups is replaced with another atom or an atomic group, and Monomers having a carboxylic acid group (-COOH group) containing a carbonyl group in the group, a salt thereof or an acid anhydride group thereof (-C(=O)-OC(=O)- group). Is.
As the salt of the (meth)acrylic acid-based monomer (acid group-containing monomer), the same salts as the salts of the carboxylic acid group can be mentioned.
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 a structural unit derived from a (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer. The (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer means a monomer having a structure in which a 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 include a functional group (hydroxyl group, amino group, glycidyl group, etc.). One or more acryloyl groups or methacryloyl groups may be contained in the (meth)acrylic-based monomer other than the (meth)acrylic acid (salt)-based monomer.

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, and other than that. In addition, other copolymerizable unsaturated bond-containing monomer may be contained. Therefore, the (meth)acrylic polymer has a structural unit derived from a (meth)acrylic acid (salt) monomer and a structural unit derived from a (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer. Other than that, it may also contain a structural unit derived from another copolymerizable unsaturated bond-containing monomer.
When the monomer component for obtaining the (meth)acrylic polymer contains the (meth)acrylic acid (salt) monomer, the dispersibility of cement in the obtained polymer emulsion is improved. In addition, by including a (meth)acrylic monomer other than the (meth)acrylic acid (salt) monomer and other copolymerizable unsaturated bond-containing monomer, the acid value of the polymer and the glass transition temperature (Tg) It will be easier to adjust etc. The unsaturated bond of the unsaturated bond-containing monomer is preferably a carbon-carbon double bond.

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

Examples of (meth)acrylic monomers other than the (meth)acrylic acid (salt) monomers include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, 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, Octadecyl acrylate, octadecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, and other (meth)acrylic acid alkyl esters having 4 to 30 carbon atoms; 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2 -(Meth)acrylic acid hydroxyalkyl ester having 4 to 30 carbon atoms such as hydroxypropyl methacrylate; ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1 And 6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, polyfunctional (meth)acrylates such as glycidyl (meth)acrylate, and the like. One or two of these It is preferable to use the above.

The monomer component serving as the raw material of the (meth)acrylic polymer is 20% by mass or more of (meth)acrylic monomers other than the (meth)acrylic acid (salt) type monomer, based on 100% by mass of all the monomer components. It is preferably contained, more preferably 40 mass% or more, still more preferably 60 mass% or more. Further, it is preferable that the (meth)acrylic-based monomer other than the (meth)acrylic acid (salt)-based monomer is contained in an amount of 99.9% by mass or less based on 100% by mass of all the monomer components, and 99.5% by mass. It is more preferable to contain the following.

The (meth)acrylic-based monomer other than the (meth)acrylic acid (salt)-based monomer contained in the 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 the monomer components as the raw material of the (meth)acrylic polymer, and further preferably , 70 mass% or more.

As the (meth)acrylic acid (salt)-based monomer and the other copolymerizable unsaturated bond-containing monomer other than the (meth)acrylic-based monomer other than the (meth)acrylic acid (salt)-based monomer, an aromatic Examples thereof include a monomer having a ring and a copolymerizable unsaturated bond.

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

When the monomer component as a raw material of the (meth)acrylic polymer contains a monomer containing the aromatic ring and a copolymerizable unsaturated bond, it may be contained in an amount of 1% by mass or more based on 100% by mass of all the monomer components. The content is preferably 5 mass% or more, more preferably 10 mass% or more, still more preferably 20 mass% or more, and particularly preferably 40 mass% or more. Further, the monomer component preferably contains 80% by mass or less, and 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 components. , 60 mass% or less is more preferable. It is not necessary to use a monomer containing an aromatic ring and a copolymerizable unsaturated bond as a monomer component that is a raw material of the (meth)acrylic polymer.

Other copolymerizable unsaturated bond-containing monomers other than the above, for example, crotonic acid, tiglic acid, 3-methylcrotonic acid, 2-methyl-2-pentenoic acid, maleic acid, itaconic acid, mesaconic acid, citraconic acid, Acid (salt) monomers other than (meth)acrylic acid (salt) monomers such as fumaric acid and its salts; C3-10 fatty acid vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate; diallyl phthalate, Polyfunctional compounds such as triallyl cyanurate, acrylonitrile, and trimethylolpropane diallyl ether; and nitrogen atom-containing monomers such as methacrylonitrile, (meth)acrylamide, and diacetone acrylamide, and one or more of these may be used. Can be used.

When the monomer component as the raw material of the (meth)acrylic polymer contains an acid (salt)-based monomer other than the (meth)acrylic acid (salt)-based monomer, 0.1% of 100% by mass of all the monomer components is used. It is preferable that the content is up to 5 mass %. The content is more preferably 0.3 to 4% by mass, and further preferably 0.5 to 3% by mass.
The monomer component as a raw material of the (meth)acrylic polymer contains an acid (salt)-based monomer other than the (meth)acrylic acid (salt)-based monomer, and contains the above-mentioned other copolymerizable unsaturated bond When a monomer is contained, it is preferably contained in an amount of 1.1 to 12 mass% in 100 mass% of all monomer components. It is more preferably 1.3 to 10% by mass, and even more preferably 1.5 to 8.0% by mass.

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

The amount of the aqueous solvent contained in the polymer emulsion is preferably 40 to 80% by mass based on 100% by mass of the entire polymer emulsion. It is more preferably 45 to 72% by mass, and even 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, and further 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) were connected in series and used Eluent: tetrahydrofuran (THF)
Standard substance for calibration curve: polystyrene (manufactured by Tosoh Corporation)
Measurement method: The object to be measured is dissolved in THF so that the solid content is about 0.2% by mass, and the molecular weight is measured using the product filtered through a filter as a measurement sample.

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

The viscosity of the polymer emulsion is not particularly limited, but is preferably 1 to 10,000 mPa·s. When the viscosity of the resin emulsion is in such a range, it becomes possible to easily mix it when actually preparing the polymer cement. The viscosity is more preferably 5 to 4000 mPa·s, further preferably 10 to 2000 mPa·s.
The viscosity of the polymer emulsion can be measured with a B-type viscometer.

In the polymer emulsion, the average particle size of emulsion particles is preferably 10 to 5000 nm. The thickness is more preferably 50 to 500 nm, further preferably 80 to 200 nm.
The average particle size of emulsion particles of the polymer emulsion can be measured by a dynamic light scattering measurement method.

The polymer emulsion can be produced by emulsion-polymerizing a monomer component as a raw material. The mode of carrying out 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 conducting polymerization. Further, a polymerization chain transfer agent or the like may be used for controlling the molecular weight.

The aqueous solvent is not particularly limited, and examples thereof include water, a mixed solvent of one or more solvents that can be mixed with water, and a mixed solvent obtained by mixing such a solvent so that water is a main component. Etc. Of these, water is preferable.

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-mentioned 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. Further, as a method of adding the monomer component, the polymerization initiator and the like, for example, a batch addition method, a continuous addition method, a multi-step addition method or the like can be applied. Also, these addition methods may be combined appropriately.

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

In the above method for producing a 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 mass% in terms of solid content based on 100 mass% of the total amount of polymer cement mortar and polymer cement concrete. It is preferable to set so that It is more preferably 0.5 to 20% by mass, and even more preferably 1.0 to 15% by mass. In addition, in this specification, solid content can be measured as follows.
[Solid content measurement method]
1. Weigh an aluminum dish precisely.
2. Precisely measure the solid content measurement product in the aluminum dish precisely weighed in 2.1.
3. The solid content measurement product precisely weighed in 2 is put in a drier controlled at 130° C. under a nitrogen atmosphere for 1.5 hours.
4. After 1 hour, remove from the dryer and allow to cool for 15 minutes in a desiccator at room temperature.
5.15 minutes later, take out from the desiccator, and weigh the aluminum dish and the measurement object precisely.
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 polymer cement mortar, the cement used in the polymer cement concrete is not particularly limited as long as it has hydraulic or latent hydraulic properties, for example, ordinary Portland cement, early strength Portland cement, moderate heat Portland cement, low heat Portland cement. Portland cement such as silica cement, fly ash cement, blast furnace cement, alumina cement, belite high content cement, various mixed cements; tricalcium silicate, dicalcium silicate, tricalcium aluminate, tetracalcium iron aluminate, etc. The constituent components of the above are: fly ash, silica fume, slag, lime fine powder, etc., which have latent hydraulic properties. These may be used alone or in combination of two or more. Of these, ordinary Portland cement is usually often used and can be suitably applied.

As the aggregate used for the polymer cement mortar and polymer cement concrete, in addition to sand, gravel, crushed stone, granulated slag, recycled aggregate, etc., silica stone, clay, zircon, high alumina, silicon carbide, graphite Examples of the refractory aggregates include qualitative, chromic, chromic, magnesia, and the like, 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 other additives than the above (meth)acrylic polymer emulsion.
The term "other additives" as used herein means components other than polymer cement mortar, cement contained in polymer cement concrete, water, aggregate, and the above (meth)acrylic polymer emulsion.

Other additives include commonly used cement dispersants and water reducing agents, water-soluble polymeric substances, retarders, quick-setting agents, early-strengthening agents/accelerators, mineral oil-based defoamers, oil-and-fat defoamers, Fatty acid type defoaming agent, fatty acid ester type defoaming agent, oxyalkylene type defoaming agent, alcohol type defoaming agent, amide type defoaming agent, phosphate ester type defoaming agent, metal soap type defoaming agent, silicone type defoaming agent Foaming agent, AE agent, surfactant, waterproofing agent, anticorrosive agent, antiseptic agent, crack reducing agent, expanding agent, cement wetting agent, thickening agent, separation reducing agent, coagulant, drying shrinkage reducing agent, strength enhancing agent. Cement additives (materials) such as self-leveling agents, colorants, fungicides, blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, colloidal silica, fibers, gypsum, etc. To be

The cement dispersant (water reducing agent) is not particularly limited, and examples thereof include (i) polyalkylaryl sulfonate-based dispersants such as naphthalene sulfonic acid formaldehyde condensate; melamine formalin resins such as melamine sulfonic acid formaldehyde condensate and sulfone. Acid salt-based dispersants; Aromatic aminosulfonate-based dispersants such as aminoarylsulfonic acid-phenol-formaldehyde condensates; Ligninsulfonate-modified ligninsulfonate-based ligninsulfonate-based dispersants; Polystyrene sulfone As described in JP-B-59-18338 and JP-A-7-223852, various sulfonic acid-based dispersants (water reducing agents) having a sulfonic acid group in the molecule, such as acid salt-based dispersants; Polyalkylene glycol mono(meth)acrylic acid ester-based monomers, (meth)acrylic acid-based monomers, and copolymers obtained from monomers copolymerizable with these monomers; JP-A-10- Unsaturated (poly)alkylene glycol ether monomer, maleic acid monomer as described in JP-A-236858, JP-A-2001-220417, JP-A-2002-121055, and JP-A-2002-121056. Or a copolymer obtained from a (meth)acrylic acid-based monomer; various polycarboxylic acid-based dispersants (water-reducing agents) having a (poly)oxyalkylene group and a carboxyl group in the molecule, such as (iii) As described in JP-A-2006-52381, (alkoxy)polyalkylene glycol mono(meth)acrylate, a phosphoric acid monoester-based monomer, a copolymer obtained from a phosphoric acid diester-based monomer, and the like, A copolymer having a (poly)oxyalkylene group and a phosphoric acid ester group in the molecule; as described in JP-A-2008-517080, a (poly)oxyalkylene group and an aromatic ring group and/or a heterocyclic group. A monomer having an aromatic group, a monomer having a phosphoric acid (salt) group and/or a phosphoric acid ester group and an aromatic ring group and/or a heterocyclic aromatic group, and an aldehyde compound Condensation products; various phosphoric acid-based dispersants such as aromatic triazine structural units, polyalkylene glycol structural units, and dispersants having a phosphoric acid ester structural unit as described in JP-A-2005-508384; ) And the like.
Among these, it is preferable that the polymer cement mortar and the polymer cement concrete further contain a water reducing agent. This further improves the adhesiveness of the paste component to the aggregate.

The above-mentioned quick-setting agent is not particularly limited as long as it is a known quick-setting agent. The quick-setting agent used may be a powder quick-setting agent, a liquid quick-setting agent, or a slurry type quick-setting agent. Examples of the liquid quick-setting agent include aluminum sulfate, fluorine, alkali metal, and those containing these and alkanolamine, and one or more of these may be used. Further, a known water-soluble hydration accelerator can be used for the liquid quick-setting agent used in the present invention. Examples of the hydration accelerator include organic hydration accelerators such as formic acid or a salt thereof, acetic acid or a salt thereof, and lactic acid or a salt thereof, water glass, nitrate, nitrite, thiosulfate, and thiocyanic acid. It is possible to use an inorganic hydration accelerator such as salt. Examples of the powder quick-setting agent 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 defoaming agent is not particularly limited as long as it is a known defoaming agent. For example, mineral oil-based defoaming agents such as kerosene and liquid paraffin; oil-and-fat defoaming agents such as animal and vegetable oils, sesame oil, castor oil and their alkylene oxide adducts; fatty acids such as oleic acid, stearic acid and their alkylene oxide adducts. Defoaming agents: Diethylene glycol monolaurate, glycerin monoricinolate, alkenyl succinic acid derivatives, sorbitol monolaurate, sorbitol trioleate, polyoxyethylene monolaurate, polyoxyethylene sorbitol monolaurate, fatty acid esters such as natural wax Alcohol defoaming agents such as octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols, polyoxyalkylene glycols; amide defoaming agents such as polyoxyalkylene amides and acrylate polyamines; tributyl phosphate, sodium Phosphate ester defoamer such as octyl phosphate; Metal soap defoamer such as aluminum stearate and calcium oleate; Silicone defoamer such as silicone oil, silicone paste, silicone emulsion, organic modified polysiloxane, fluorosilicone oil 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, the oxyalkylene antifoaming agent is most preferable. When the cement admixture copolymer of the present invention and an oxyalkylene defoaming agent are used in combination, the amount of defoaming agent used is small, and the compatibility between the defoaming agent and the copolymer is also 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 having an action of reducing bubbles in the aqueous liquid, but among them, it is represented by the following general formula (2). Specific oxyalkylene antifoams are preferred.
R ¹ {-T-(R ² O)t-R ³ }n (2)
In the above formula (2), R ¹ and R ³ are the same or different and each is 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, or phenyl. Group or an alkylphenyl group (the alkyl group in the alkylphenyl group has 1 to 22 carbon atoms). R ² O represents one or a mixture of two or more oxyalkylene groups having 2 to 4 carbon atoms, and in the case of two or more, R ² O may be added in a block form or in a random form. t is the average number of moles of oxyalkylene groups added, and represents a number of 0 to 300. When t is 0, R ¹ and R ³ are not hydrogen atoms at the same time, and T represents a —O—, —CO ₂ —, —SO ₄ —, —PO ₄ — or —NH— group. n represents an integer of 1 or 2, and when R ¹ is a hydrogen atom, n is 1.

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 (Poly)oxyalkylene alkyl ethers such as oxypropylene butyl ether, polyoxyethylene polyoxypropylene-2-ethylhexyl ether, and oxyethyleneoxypropylene adducts of 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-polymerizing alkylene oxides to acetylene alcohols such as 2,5-diol and 3-methyl-1-butyn-3-ol; diethylene glycol oleate, diethylene glycol lauryl ester, ethylene glycol distearate, etc. (Poly)oxyalkylene fatty acid esters; (poly)oxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate ester, polyoxyethylene sorbitan trioleate ester; sodium polyoxypropylene methyl ether sulfate, polyoxyethylene dodecyl phenol (Poly)oxyalkylene alkyl (aryl) ether sulfate ester salts such as sodium ether sulfate; (poly)oxyalkylene alkyl phosphate esters such as (poly)oxyethylene stearyl phosphate ester; ) Oxyalkylenealkylamines; and the like, and one or more of these can be used.

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

In the polymer cement mortar and polymer cement concrete, the compounding ratio of the defoaming agent is 0.01 to 1% by mass in terms of solid content based on 100% by mass of the total amount of polymer cement mortar and polymer cement concrete. It is preferable. It is more preferably 0.05 to 0.5% by mass, and further preferably 0.07 to 0.3% by mass.

In the polymer cement mortar and polymer cement concrete, the unit water amount per 1 m ³ , the cement usage amount and the water/cement ratio are not particularly limited, and for example, the unit water content 100 to 300 kg/m ³ , the used cement amount 300 to 500 kg. /M ³ , and water/cement ratio (weight ratio)=0.35 to 0.6. More preferably, the unit water amount is 140 to 240 kg/m ³ , the used cement amount is 350 to 480 kg/m ³ , and the water/cement ratio (weight ratio)=0.4 to 0.5.

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

Polymer cement mortar used in the construction method of the member of the present invention, concrete other than polymer cement concrete can be used normal concrete, the polymer cement mortar described above, cement as a raw material of polymer cement concrete, similar to aggregate The same can be used, and the water/cement ratio and the aggregate/cement ratio are the same as those of polymer cement mortar and polymer cement concrete.
As the reinforcing bar used in the construction method of the member of the present invention, the reinforcing bar generally used in the fields of civil engineering and construction can be used.

The construction method of the member of the present invention is a construction method capable of constructing a concrete structure excellent in abrasion resistance and durability while suppressing the cost with good workability, and the construction of the surface layer portion of the dam damping work described above. However, the application is not limited to this, and it can also be applied to drainage pipes and intake pipes of dams (particularly where the cross section shrinks and the water pressure increases). It can also be applied to places where abrasion resistance is required. For example, it can be applied to bridge floor slabs, shield segments, steel shell blocks, floor members for construction, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. In addition, "part" means "part by weight" and "%" means "% by mass" unless otherwise specified.

Including this example, the Tg of the homopolymer used for calculating the glass transition temperature (Tg) of the monomer components constituting the polymer from the Fox calculation formula is 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 by using a particle size distribution measuring device (Otsuka Electronics Co., Ltd. FPAR-1000) by a dynamic light scattering method.
<Solid content (N.V.)>
About 1 g of the obtained emulsion was weighed and dried in a hot air dryer at 150° C. for 1 hour, and the remaining dry amount was regarded as the non-volatile content, and the ratio with respect to the mass before drying was represented by mass %.

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

Synthesis examples 2-5
Resin emulsions 2 to 5 for cement additives 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 the obtained emulsions 2 to 5.

Examples 1-5, Comparative Example 1
1. Preparation of Polymer Cement Mortar Using the resin emulsions 1 to 5 for cement additives synthesized in Synthesis Examples 1 to 5, compounding was performed as in Formulation Example 1 to prepare mortars of Test Examples 1 to 5. The amount of emulsion added was adjusted so that the emulsion solid content was 20% by weight with respect to the cement, and the amount of water in the emulsion was added so that the amount of water was 30% by weight with respect to the cement, and the additional water content was adjusted. Also, a mortar of Comparative Test Example 1 to which no emulsion was added as a blank was prepared as in Formulation Example 2.
The operation for producing the mortar was performed according to the method for producing the polymer cement mortar described below.
[Mortar formulation example 1]
C/S/W/P/antifoaming agent 1/antifoaming agent 2=780 g/858 g/234 g/156 g/3.1 g/2.3 g (W/C=0.3, S/C=1.1, (P/C=0.2, total defoamer/C=0.007)
C: Ordinary Portland cement (manufactured by Taiheiyo Cement)
S: Silica Sand No. 7 (manufactured by Toyo Materan)
W: Total amount of pure water added and water contained in the polymer emulsions synthesized in Synthesis Examples 1 to 5 P: Solid content of emulsion Defoamer 1: MA-404 (manufactured by BASF Japan), relative to cement 0.4 mass% defoaming agent 2: Nopco 8034L (manufactured by San Nopco), 0.3 mass% added to cement [Mortar formulation example 2]
C/S/W/water reducing agent/antifoaming agent=780 g/858 g/234 g/0.8 g/3.1 g
C: Ordinary Portland cement (manufactured by Taiheiyo Cement)
S: Silica Sand No. 7 (manufactured by Toyo Materan)
W: 0.1% by mass of added pure water amount reducing agent: polycarboxylic acid type water reducing agent (manufactured by Nippon Shokubai) with respect to cement Defoaming agent: MA-404 (manufactured by BASF Japan) with respect to cement Addition of 4% by mass <Method for producing polymer cement mortar>
Under a temperature of 20°C ± 1°C and a relative humidity of 60% ± 10%, a stainless beater (stirring blade) is attached to a Hobart type mortar mixer (model number N-50; manufactured by Hobart), and C and S are attached. It was charged and kneaded at a first speed for 120 seconds. Next, after adding C and S and kneading at 1st speed for 60 seconds, the mixer was stopped, mortar was scraped off for 30 seconds, and then kneading at 1st speed for 120 seconds to prepare a mortar. ..

2. Evaluation of Polymer Cement Mortar The polymer cement mortar of Test Examples 1 to 5 and Comparative Test Example 1 were evaluated as follows. Table 3 shows the results of the 15 shot flow value measurement and mortar air amount measurement, and Table 4 shows the bending strength measurement results.
<15 stroke flow value measurement>
The mortar was transferred from the kneading container to a polyethylene 1 L container, stirred 20 times with a spatula, and immediately filled with a half amount in a flow cone (described in JIS R 5201-2015) placed on a flow measurement plate (30 cm×30 cm) 15 times. I pierced it with a stick, then filled it with mortar to the point where the flow cone was full, and pierced it 15 times with a stick, and finally made up the deficiency and smoothed the surface of the slump cone. Immediately thereafter, the flow cone was pulled up vertically and given 15 times of drop motions for 15 seconds, and then the 15-stroke flow of the mortar was measured, and this was taken as the 15-stroke flow value. The measurement of the flow was performed according to JIS R 5201-2015. The larger the value of the flow, the higher the dispersibility.
<Mortar air volume measurement>
The measurement of the mortar air amount (initial air amount) was performed by the method of JIS-A-1128 (2014 revision). About 200 mL of a mortar was filled in a 500 mL glass graduated cylinder, and was pierced with a round bar having a diameter of 8 mm, and was vibrated lightly by hand to remove coarse bubbles. Furthermore, after adding about 200 mL of mortar and removing air bubbles in the same manner, 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) Preparation of Bending Strength Specimen The specimen (4×4×16 cm) used for bending strength was prepared in accordance with JIS A 1171-2016 using kneaded mortar according to the <Method for producing polymer cement mortar>. It carried out according to the described method.
That is, polymer cement mortar adjusted to a 4×4×16 cm mold is packed into two layers and molded. Polymer cement was filled up to about half the height of the mold, and the whole surface was pierced with a stick rod. Then, vibration was applied to the mold container to remove coarse bubbles. Next, the polymer cement was filled up to the upper end of the mold, and the entire surface was pierced with a stick rod. Then, the mold container was vibrated to remove coarse bubbles. Finally, after acclimating the surface to a flat surface, the container was sealed and stored at 20° C. for initial curing (sealing curing). After one day, the mold was removed, followed by curing to prepare a flexural strength test piece. The curing was carried out at 20° C. for 28 days in the case of room temperature curing, and at 90° C. for 48 hours and then at 20° C. for 25 days in the case of steam curing. In the case of dry curing, it was cured at 90° C. for 48 hours, then at 100° C. for 24 hours, and then at 20° C. for 24 days.
(2) Bending strength measurement Using the bending strength specimen prepared in (1) above, bending strength was measured according to the method described in JIS R 5201-2015. The strength tester used was a full-automatic pressure resistance tester (TYPE: ACA-50S-B2, manufactured by Maekawa Test Machine Co., Ltd.), and a dedicated bending strength jig was installed for the test.

Example 6, Comparative Examples 2-4
1. Preparation of Polymer Cement Concrete The resin emulsion 2 for cement additive synthesized in Synthesis Example 2 was blended as in Blend Example 1 to produce a concrete of Test Example 6. The amount of emulsion added was adjusted so that the emulsion solid content was 20% by weight with respect to the cement, and the amount of water in the emulsion was added so that the amount of water was 55% by weight with respect to the cement to adjust the additional water content. In addition, a concrete of Comparative Test Example 2 as a blank to which the emulsion was not added was prepared as in Mixing Example 2.
[Concrete mix example 1]
W/C/S Coarse/S Fine/G Large/G Small/Admixture/P/Admixture 1/Admixture 2=
2.306 kg/9.00 kg/21.55 kg/4.70 kg/16.51 kg/11.95 kg/0.51 kg/4.444 kg/4.5 g/18.0 g
(W/C=0.55, P/C=0.2, total defoamer/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)
S coarse: crushed sand, from Hachioji Miyama S Fine: mountain sand, from Yoshino, Kimitsu City, Chiba Prefecture
G Large: Coarse aggregate, Ome from Tokyo G Small: Coarse aggregate, Ome admixture from Tokyo: Sepiolite (made by Tomoe Kogyo Co., Ltd.)
P: Emulsion solid content admixture 1: Defoaming agent, alcohol-based defoaming agent (Floric)
Admixture 2: AE agent, AE-4 (manufactured by Floric)
[Concrete mix example 2]
W/C/S Coarse/S Fine/G Large/G Small/Admixture 2/Admixture 3=
4.950 kg/9.00 kg/21.55 kg/4.70 kg/16.51 kg/11.95 kg/23.4 g/85.5 g
(W/C=0.55, total defoamer/C=0.005)
W: amount of pure water added C: ordinary Portland cement (manufactured by Taiheiyo Cement)
S Coarse: Crushed sand, Hachioji Miyama S Fine: Yamasuna, Yoshino from Kimitsu-shi, Chiba G Large: Coarse aggregate, Ome, Tokyo G Small: Coarse aggregate, Ome, Tokyo Admixture 2: AE, AE -4 (made by Floric)
Admixture 3: AE water reducing agent, SV10 (manufactured by Floric)
<Method for producing polymer cement concrete>
A 50-liter forced twin-screw mixer was used, and the mixing amount was 30 liters. First, materials other than W, P, and the admixtures 1 and 2 were charged, and the mixture was kneaded for 30 seconds. Next, after all the materials were charged and kneading was performed for 30 seconds, the mixer was stopped, the concrete was scraped off for 30 seconds, and then the kneading was further performed for 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 test was performed.
(1) Strength Test Preparation of Specimen Polymer cement concrete was put in a φ100×200 mm summit mold and a □100×100×400 mm mold and allowed to stand at 20° C. for 2 days, then two demolded specimens were placed. They were prepared, and one of them was subjected to the following room temperature curing and the other was subjected to dry curing.
Normal temperature curing: curing at 20° C. and 80% humidity for 28 days.
Dry curing: After curing at 20° C. and 80% humidity for 2 days, it is cured at 90° C. and 80% humidity for 2 days, and further at 100° C. for 3 days.
(2) Compressive strength test Regarding the specimen after curing, the compressive strength was measured according to JIS A 1108. The results are shown in Table 5.
(3) Split tensile strength test The split tensile strength of the specimen after curing was measured according to JIS A 1113. The results are shown in Table 5.
(4) Bending strength test Regarding the specimen after curing, the bending strength was measured according to JIS A 1106. The results are shown in Table 5.

Example 7, Comparative Examples 5-7, Reference Examples 1-2
1. Preparation of Polymer Cement Concrete Using the resin additive 2 for cement additive synthesized in Synthesis Example 2, the mixture was blended as in Blend Example 3 to produce the concrete of Test Example 7. The amount of emulsion added was adjusted so that the emulsion solid content was 49% by weight with respect to the cement, and the amount of water in the emulsion was added so that the amount of water was 26% by weight with respect to the cement to adjust the additional water content. Further, a concrete of Comparative Test Example 3 as a blank to which the emulsion was not added was prepared as in Mixing Example 4.
[Concrete mix example 3]
W/C/S Coarse/S Fine/G Large/G Small/Admixture/P/Admixture 1/Admixture 2=
2.306 kg/9.00 kg/21.55 kg/4.70 kg/16.51 kg/11.95 kg/0.51 kg/4.444 kg/4.5 g/18.0 g
(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, Hachioji Miyama S Fine: Yamasuna, Yoshino from Kimitsu City, Chiba G Large: Coarse aggregate, Ome from Tokyo G Small: Coarse aggregate, Ome admixture from Tokyo: Sepiolite Made)
P: Cement additive resin emulsion 2 synthesized in Synthesis Example 2
Admixture 1: Defoaming agent, alcohol-based defoaming agent (Floric)
Admixture 2: AE agent, AE-4 (manufactured by Floric)
[Concrete mix example 4]
W/C/S Coarse/S Fine/G Large/G Small/Admixture 2/Admixture 3=
4.950 kg/9.00 kg/21.55 kg/4.70 kg/16.51 kg/11.95 kg/23.4 g/85.5 g
(W/C=0.55, total defoamer/C=0.005)
W: amount of pure water added C: ordinary Portland cement (manufactured by Taiheiyo Cement)
S Coarse: Crushed sand, Hachioji Miyama S Fine: Yamasuna, Yoshino from Kimitsu-shi, Chiba G Large: Coarse aggregate, Ome, Tokyo G Small: Coarse aggregate, Ome, Tokyo Admixture 2: AE, AE -4 (made by Floric)
Admixture 3: AE water reducing agent, SV10 (manufactured by Floric)
<Method for producing polymer cement concrete>
A 50-liter forced twin-screw mixer was used, and the mixing amount was 30 liters. First, materials other than W, P, and the admixtures 1 and 2 were charged, and the mixture was kneaded for 30 seconds. Next, after all the materials were charged and kneading was performed for 30 seconds, the mixer was stopped, the concrete was scraped off for 30 seconds, and then the kneading was further performed for 60 seconds to prepare concrete.

2. Scratch resistance strength test Regarding the polymer cement concretes of Test Example 7 and Comparative Test Example 3, the following scuff resistance evaluation was performed.
(1) Abrasion resistance test Preparation of test specimen Polymer cement concrete was filled in a steel box having an inner surface width of 143 mm, a length of 297 mm, and a thickness of 32.5 mm, and allowed to stand at 20° C. for 24 hours, and then demolded. Two specimens were prepared, and one of them was subjected to the following room temperature curing and the other was subjected to dry curing.
Normal temperature curing: curing at 20° C. and 80% humidity for 28 days.
Drying curing: heating to 90°C at 15°C/hour, curing at 90°C and 80% humidity for 48 hours, then cooling to 20°C at 5°C/hour, and further drying in a drying oven at 100°C for 24 hours. Carry out.
(2) Scratch resistance test We adopted the Okuda-type scuffing test, which was invented at the Central Research Institute of Electric Power Industry, and confirmed the presence or absence of polymer and the difference in curing method. The test method was as follows: The test specimen prepared as described above was placed in a rotating drum in which carbon steel sylpep was inserted, and about 5 L/min of water was showered from the pipe in the center of the tester, The test was carried out by rotating the rotary drum at the number of revolutions, and the wear coefficient was calculated 4 hours after the start of the test. For reference, the abrasion test uses the long-life concrete (registered trademark: EIEN. The composition is described in JP 2006-182583 A) described in Patent Document 7 described above, and promotes 5% CO ₂ neutralization by neutralization. 85°C, 80% humidity, using a specimen that has been left to stand for 28 days in a tank (20°C, 60% humidity) and the ultra-high-strength fiber-reinforced concrete (registered trademark: Saxem) described in Patent Document 3. It was also conducted on a test piece prepared by steam curing for 24 hours. The results are shown in Table 6 and FIG. The smaller the abrasion coefficient, the better the abrasion resistance.

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 further, abrasion resistance is equivalent to that of EIEN and SAXEM, and is low in abrasion resistance. Was also confirmed to be excellent. Therefore, by using these on the member surface, it is possible to construct a structural member having excellent strength and scuff resistance.
Although EIEN and Saxem are also excellent in abrasion resistance, they are higher in cost than the polymer cement mortar and polymer cement concrete used in the present invention, and require special curing or require a special material. Therefore, the versatility of the present invention, which can be produced with the same composition as ordinary concrete, is high.

1: Reinforcing bar 2: Normal 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 part of the member is constructed of a material made of polymer cement,
A reinforcing bar assembly process for building a reinforcing bar to be placed inside the member,
A concrete pouring step of pouring concrete in an area excluding at least a part of the surface layer portion of the member surface,
A polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete on the surface layer portion where concrete is not placed in the concrete placing step,
A heating step of heating the member after casting the polymer cement mortar or polymer cement concrete at a temperature not lower than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100°C. Construction method of the member to be. A method of constructing a member, wherein a part of the member is constructed of a material made of polymer cement,
Polymer cement mortar/concrete placing step of placing polymer cement mortar or polymer cement concrete on at least part of the surface layer of the member surface,
A heating step of heating the surface layer portion on which the polymer cement mortar or polymer cement concrete is placed at a temperature not lower 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 building a reinforcing bar to be placed inside the member,
And a concrete pouring step of pouring concrete in a region excluding the surface layer portion. A method of constructing a member, wherein a part of the member is constructed of a material made of polymer cement,
An embedded formwork installation step of arranging an embedded formwork having a polymer cement mortar or polymer cement concrete layer on at least a part of the outside,
A reinforcing bar assembling step of building a reinforcing bar inside the buried formwork;
Including a concrete placing step of placing concrete inside the buried form,
The embedded formwork was constructed through a heating step of heating the polymer cement mortar or polymer cement concrete layer at a temperature not lower than the glass transition temperature of the polymer used for the polymer cement and at a temperature of 40 to 100°C. A construction method of a member characterized by being a thing. The said heating process is performed at the temperature of 50-100 degreeC, The construction method of the member in any one of Claims 1-3 characterized by the above-mentioned. The method for constructing a member according to any one of claims 1 to 4, wherein the polymer used for the polymer cement has a glass transition temperature of 35 to 100°C.

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