JP2020148678A - Drying shrinkage strain estimation method - Google Patents
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- 238000001035 drying Methods 0.000 title claims abstract description 91
- 238000000034 method Methods 0.000 title claims abstract description 45
- 238000006073 displacement reaction Methods 0.000 claims abstract description 49
- 239000004568 cement Substances 0.000 claims abstract description 19
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- 230000001678 irradiating effect Effects 0.000 claims description 2
- 238000012360 testing method Methods 0.000 abstract description 9
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- 238000005259 measurement Methods 0.000 description 15
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- FOGYNLXERPKEGN-UHFFFAOYSA-N 3-(2-hydroxy-3-methoxyphenyl)-2-[2-methoxy-4-(3-sulfopropyl)phenoxy]propane-1-sulfonic acid Chemical compound COC1=CC=CC(CC(CS(O)(=O)=O)OC=2C(=CC(CCCS(O)(=O)=O)=CC=2)OC)=C1O FOGYNLXERPKEGN-UHFFFAOYSA-N 0.000 description 1
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- 239000011372 high-strength concrete Substances 0.000 description 1
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- Length Measuring Devices By Optical Means (AREA)
Abstract
Description
本発明は、セメントペースト硬化体、コンクリート、およびモルタル（以下「セメント質硬化体」という。）の、ＪＩＳ Ａ １１２９−１、ＪＩＳ Ａ １１２９−２、またはＪＩＳ Ａ １１２９−３（以下「ＪＩＳ Ａ １１２９−１〜３」という。）に準拠して測定した、乾燥期間が６か月における乾燥収縮ひずみの値を早期に推定する、乾燥収縮ひずみの推定方法に関する。 The present invention relates to a hardened cement paste, concrete, and mortar (hereinafter referred to as "hardened cementum"), JIS A 1129-1, JIS A 1129-2, or JIS A 1129-3 (hereinafter "JIS A 1129"). It relates to a method for estimating dry shrinkage strain, which estimates the value of dry shrinkage strain at an early stage when the drying period is 6 months, which is measured according to (-1 to 3).
従来、セメント質硬化体の乾燥収縮ひずみを測定する方法は、ＪＩＳ Ａ １１２９−１に規定するコンパレータを用いる方法、ＪＩＳ Ａ １１２９−２に規定するコンタクトゲージを用いる方法、およびＪＩＳ Ａ １１２９−３に規定するダイヤルゲージを用いる方法がある。しかし、これらの方法はいずれも、乾燥期間が６か月における乾燥収縮ひずみの値を得るのに、６か月もの長期間を要するほか、所定の期間毎に、１０ｃｍ×１０ｃｍ×４０ｃｍの供試体（セメント質硬化体）の長さを測定しなければならず、測定作業に手間がかかった。 Conventionally, the method of measuring the drying shrinkage strain of a cementum hardened product is a method using a comparator specified in JIS A 1129-1, a method using a contact gauge specified in JIS A 1129-2, and a method using JIS A 1129-3. There is a method using a specified dial gauge. However, in each of these methods, it takes a long period of 6 months to obtain the value of the drying shrinkage strain when the drying period is 6 months, and the specimen of 10 cm × 10 cm × 40 cm is obtained every predetermined period. The length of the (cementum hardened body) had to be measured, which took time and effort.
そこで、特許文献１では、コンクリートの乾燥収縮ひずみを、早期に評価する方法が提案されている。該方法は、温度８０℃における乾燥期間２８日目の乾燥収縮ひずみの実測値と、温度２０℃における最終乾燥収縮ひずみ値との関係式、または、温度８０℃における最終乾燥収縮ひずみ値と、温度２０℃における最終乾燥収縮ひずみ値との関係を、それぞれ一次式で近似した関係式を用いて、任意の長期材齢におけるコンクリートの乾燥収縮ひずみを早期に評価する方法である。しかし、この方法では、関係式を得るのに手間がかかるほか、温度８０℃における最終乾燥収縮ひずみ値と、温度２０℃における最終乾燥収縮ひずみ値との関係が線形でない場合は、評価の精度が低下する。 Therefore, Patent Document 1 proposes a method for early evaluation of the drying shrinkage strain of concrete. The method is a relational expression between the measured value of the drying shrinkage strain at a temperature of 80 ° C. on the 28th day of the drying period and the final drying shrinkage strain value at a temperature of 20 ° C., or the final drying shrinkage strain value at a temperature of 80 ° C. and the temperature. This is a method for early evaluation of the dry shrinkage strain of concrete at an arbitrary long-term age by using relational expressions that approximate the relationship with the final dry shrinkage strain value at 20 ° C. by linear equations. However, with this method, it takes time to obtain the relational expression, and if the relationship between the final drying shrinkage strain value at a temperature of 80 ° C. and the final drying shrinkage strain value at a temperature of 20 ° C. is not linear, the evaluation accuracy is high. descend.
そこで、本発明は、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した、乾燥期間６か月における乾燥収縮ひずみの値を早期に推定する、乾燥収縮ひずみの推定方法を提供することを目的とする。 Therefore, an object of the present invention is to provide a method for estimating dry shrinkage strain, which is measured according to JIS A 1129-1 to 3 and which estimates the value of dry shrinkage strain at a drying period of 6 months at an early stage. To do.
本発明者は、前記目的にかなう乾燥収縮ひずみの推定方法を鋭意検討した結果、特定の乾燥収縮ひずみ測定装置を用いて測定した乾燥収縮ひずみの終局値に特定の係数を乗ずれば、前記目的を達成できることを見出し、本発明を完成させた。
すなわち、本発明は、以下の構成を有する乾燥収縮ひずみの推定方法である。
As a result of diligently studying a method for estimating dry shrinkage strain that meets the above object, the present inventor obtains the above object by multiplying the final value of dry shrinkage strain measured using a specific dry shrinkage strain measuring device by a specific coefficient. The present invention was completed by finding that the above can be achieved.
That is, the present invention is a method for estimating dry shrinkage strain having the following constitution.
［１］下記（Ａ）および（Ｂ）の工程を経て取得した乾燥収縮ひずみの終局値に、表１に記載のセメントの種類に応じて選択した係数を乗じて得た値を、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した、乾燥期間６か月における乾燥収縮ひずみの値として推定する、乾燥収縮ひずみの推定方法。
（Ａ）２個以上のレーザー変位計、乾燥収縮ひずみ測定用の供試体を支持するための正三角形の３つの頂点または正方形の４つの頂点を形成するように配置してなる支持部材、および、該支持部材の一部を埋設してなる台座、を少なくとも含む、乾燥収縮ひずみ測定装置の前記支持部材上に、円板状または四角板状の供試体の中心が、前記支持部材が形成する正三角形または正方形の中心と一致するように載置する、供試体の載置工程
（Ｂ）該供試体の周囲の側面に、レーザー変位計からレーザーを照射して、レーザー変位計と供試体の周囲の側面の間の距離を測定し、該距離が一定に達した時点の供試体の乾燥収縮ひずみを、該供試体の乾燥収縮ひずみの終局値として取得する、乾燥収縮ひずみの終局値の取得工程
［表１］
［２］２〜４個の前記レーザー変位計を、前記支持部材が形成する正三角形または正方形の中心から等間隔の位置に、レーザー照射面を該中心に向けて配置してなる、前記［１］に記載の乾燥収縮ひずみの推定方法。
［３］２〜６個の前記レーザー変位計を、該レーザー変位計から照射されたレーザーが６０〜３００°の角度で交差するように配置してなる、前記［１］または［２］に記載の乾燥収縮ひずみの推定方法。
［４］前記供試体の厚さが５〜２０ｍｍである、前記［１］〜［３］のいずれかに記載の乾燥収縮ひずみの推定方法。
［５］前記支持部材上に前記供試体を載置したままの状態で、前記供試体を乾燥する、前記［１］〜［４］のいずれかに記載の乾燥収縮ひずみの推定方法。
[1] JIS A 1129 is a value obtained by multiplying the final value of the drying shrinkage strain obtained through the steps (A) and (B) below by a coefficient selected according to the type of cement shown in Table 1. A method for estimating dry shrinkage strain, which is estimated as a value of dry shrinkage strain in a drying period of 6 months, measured according to -1 to 3.
(A) Two or more laser displacement meters, a support member arranged so as to form three equilateral triangle vertices or four square vertices for supporting a specimen for measuring dry shrinkage strain, and On the support member of the drying shrinkage strain measuring device including at least a pedestal formed by burying a part of the support member, the center of the disk-shaped or square plate-shaped specimen is formed by the support member. Placement step of specimen to be placed so as to coincide with the center of a triangle or square (B) Around the laser displacement meter and specimen by irradiating the side surface around the specimen with a laser from a laser displacement meter. The step of acquiring the ultimate value of the drying shrinkage strain, which measures the distance between the side surfaces of the specimen and acquires the drying shrinkage strain of the specimen when the distance reaches a certain value as the ultimate value of the drying shrinkage strain of the specimen. [Table 1]
[2] The laser irradiation surface is arranged toward the center of the equilateral triangle or square formed by the support member at equal intervals from the center of the two to four laser displacement gauges [1]. ]. The method for estimating dry shrinkage strain.
[3] The above-mentioned [1] or [2], wherein the two to six laser displacement gauges are arranged so that the lasers emitted from the laser displacement gauges intersect at an angle of 60 to 300 °. How to estimate the drying shrinkage strain of.
[4] The method for estimating dry shrinkage strain according to any one of [1] to [3] above, wherein the specimen has a thickness of 5 to 20 mm.
[5] The method for estimating dry shrinkage strain according to any one of [1] to [4], wherein the specimen is dried while the specimen is still placed on the support member.
本発明の乾燥収縮ひずみの推定方法は、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した、セメント質硬化体の乾燥期間６か月における乾燥収縮のひずみを、早期に精度よく推定できる。また、本発明で用いる供試体は、ＪＩＳ Ａ １１２９−１〜３で用いる供試体に比べ小さく、供試体を動かすなどの作業が容易なため、乾燥収縮ひずみの測定作業の労力を大幅に軽減できる。 The method for estimating the drying shrinkage strain of the present invention can accurately estimate the drying shrinkage strain of a cementum-hardened product at a drying period of 6 months, which is measured according to JIS A 1129-1 to 3. Further, the specimen used in the present invention is smaller than the specimen used in JIS A 1129-1 to 3, and the work such as moving the specimen is easy, so that the labor for measuring the drying shrinkage strain can be significantly reduced. ..
本発明は、前記（Ａ）および（Ｂ）の工程を経て取得した乾燥収縮ひずみの終局値に、表１に記載のセメントの種類に応じて選択した係数を乗じて得た値を、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した、乾燥期間６か月における乾燥収縮ひずみの値として推定する、乾燥収縮ひずみの推定方法である。
以下、本発明について、乾燥収縮ひずみ測定装置、乾燥収縮ひずみの測定と乾燥収縮ひずみの終局値の取得、および、乾燥収縮ひずみの推定方法に分けて詳細に説明する。
In the present invention, JIS A is obtained by multiplying the final value of the drying shrinkage strain obtained through the steps (A) and (B) by a coefficient selected according to the type of cement shown in Table 1. This is a method for estimating dry shrinkage strain, which is estimated as a value of dry shrinkage strain in a drying period of 6 months, measured according to 1129-1 to 3.
Hereinafter, the present invention will be described in detail separately for a drying shrinkage strain measuring device, a drying shrinkage strain measurement, an acquisition of a final value of the dry shrinkage strain, and a method for estimating the dry shrinkage strain.
１．乾燥収縮ひずみ測定装置
該装置は、図１〜４に例示するように、（Ａ）２個以上のレーザー変位計、（Ｂ）乾燥収縮ひずみ測定用の供試体を支持するための正三角形の３つの頂点または正方形の４つの頂点を形成するように配置してなる支持部材、および、（Ｃ）該支持部材の一部を埋設してなる台座を、少なくとも含む装置である。
1. 1. Dry shrinkage strain measuring device As illustrated in FIGS. 1 to 4, the device is an equilateral triangle 3 for supporting (A) two or more laser displacement meters and (B) a specimen for measuring dry shrinkage strain. It is a device including at least a support member arranged so as to form one vertex or four vertices of a square, and (C) a pedestal formed by embedding a part of the support member.
（Ａ）レーザー変位計
本発明で用いるレーザー変位計は、特に制限されず、反射型や透過型等の市販のレーザー変位計が挙げられる。ちなみに、図４に示す４個のレーザー変位計４は、反射型である。
本発明では、乾燥収縮ひずみの測定精度が向上するため、レーザー変位計を２個以上設置する。レーザー変位計が１個では、乾燥収縮ひずみの測定精度が低下するおそれがある。また、レーザー変位計を増やせばデータ数が増え、その分、さらに測定精度が向上するが、装置はコスト高になる。したがって、本発明において、レーザー変位計は、好ましくは２〜６個、より好ましくは２〜４個設置する。
レーザー変位計は、乾燥収縮ひずみの測定精度が向上し、また、供試体の載置が容易なため、好ましくは、支持部材が形成する正三角形または正方形の中心から等間隔の位置に、レーザー照射面を該中心に向けて設置する。また、乾燥収縮ひずみの測定精度がさらに向上するため、より好ましくは、２〜６個の前記レーザー変位計を、該レーザー変位計から照射されたレーザーが６０〜３００°の角度で交差するように配置する。
レーザー変位計を設置する態様は、レーザー変位計を２個設置する場合、例えば、図１に示すように、レーザー変位計を対向して設置するか、図２に示すように、レーザーが９０°の角度で交差するように設置し、また、レーザー変位計を４個設置する場合、図３に示すように、２組のレーザー変位計を対向して設置する。
(A) Laser Displacement Meter The laser displacement meter used in the present invention is not particularly limited, and examples thereof include commercially available laser displacement meters such as a reflection type and a transmission type. By the way, the four laser displacement meters 4 shown in FIG. 4 are of the reflection type.
In the present invention, two or more laser displacement meters are installed in order to improve the measurement accuracy of drying shrinkage strain. With one laser displacement meter, the measurement accuracy of drying shrinkage strain may decrease. Further, if the number of laser displacement meters is increased, the number of data is increased, and the measurement accuracy is further improved by that amount, but the cost of the device is increased. Therefore, in the present invention, preferably 2 to 6 laser displacement meters, more preferably 2 to 4 laser displacement meters are installed.
Since the laser displacement meter improves the measurement accuracy of drying shrinkage strain and makes it easy to place the specimen, it is preferable to irradiate the laser at positions equilaterally spaced from the center of the equilateral triangle or square formed by the support member. Install with the surface facing the center. Further, in order to further improve the measurement accuracy of the drying shrinkage strain, more preferably, 2 to 6 of the laser displacement meters are crossed so that the lasers emitted from the laser displacement meters intersect at an angle of 60 to 300 °. Deploy.
In the mode of installing the laser displacement meter, when two laser displacement meters are installed, for example, the laser displacement meters are installed facing each other as shown in FIG. 1, or the laser is 90 ° as shown in FIG. When four laser displacement meters are installed so as to intersect at the angle of the above, two sets of laser displacement meters are installed facing each other as shown in FIG.
（Ｂ）支持部材
支持部材は、供試体を台座から離して、供試体と台座の間に空間を設けるために用いる。この空間を設けることにより、供試体は均質かつ早期に乾燥するため、乾燥収縮ひずみの終局値を早期に測定できる。支持部材の形状は、特に制限されず、図１等に示す球状や柱状等が挙げられる。なお、支持部材が柱状の場合、供試体と点で接触するように、好ましくは、供試体に接する支持部材の面を半球状にする。
また、支持部材の数は、３点以上あれば供試体を安定して載置できるが、支持部材が多すぎると、装置の製造に手間がかかるため、支持部材の数は、好ましくは３〜４個である。また、前記支持部材は、供試体を安定して載置するためには、好ましくは正三角形または正方形を形成するように設置する。図１〜３は、支持部材５が正方形を形成するように、支持部材を設置した例である。なお、前記支持部材は、熱や衝撃による変形を防ぐため、好ましくはインバー鋼材を用いて製造する。
(B) Support member The support member is used to separate the specimen from the pedestal and provide a space between the specimen and the pedestal. By providing this space, the specimen dries homogeneously and early, so that the ultimate value of the drying shrinkage strain can be measured early. The shape of the support member is not particularly limited, and examples thereof include a spherical shape and a columnar shape shown in FIG. When the support member is columnar, the surface of the support member in contact with the specimen is preferably hemispherical so as to make point contact with the specimen.
Further, if the number of support members is 3 or more, the specimen can be stably placed, but if there are too many support members, it takes time to manufacture the device. Therefore, the number of support members is preferably 3 to 3. There are four. In addition, the support member is preferably installed so as to form an equilateral triangle or a square in order to stably place the specimen. FIGS. 1 to 3 show an example in which the support member is installed so that the support member 5 forms a square. The support member is preferably manufactured using Invar steel in order to prevent deformation due to heat or impact.
(Ｃ)台座
台座は、支持部材の一部（下部）を埋設して固定してなるものである。ちなみに、図１〜３に示す台座２は正方形の板状である。また、測定精度を向上させるため、台座は水平に保たれていることが好ましい。なお、前記台座は、熱や衝撃による変形を防ぐため、好ましくはインバー鋼材を用いて製造する。
(C) Pedestal The pedestal is formed by burying and fixing a part (lower part) of the support member. By the way, the pedestal 2 shown in FIGS. 1 to 3 has a square plate shape. Further, in order to improve the measurement accuracy, it is preferable that the pedestal is kept horizontal. The pedestal is preferably manufactured using Invar steel in order to prevent deformation due to heat or impact.
(Ｄ)供試体載置補助治具
本発明で用いる乾燥収縮ひずみ測定装置では、支持部材上への供試体の載置を容易にするため、供試体載置補助治具を用いてもよい。該供試体載置補助治具は、図４に示すような、台座の外側に設置された２本のピンが挙げられる。図４の乾燥収縮ひずみ測定装置の支持部材上に、例えば、直径１０ｃｍの円板状の供試体を載置する場合、前記２本のピンと接触するように前記供試体を支持部材上に載置すれば、供試体の中心と支持部材が形成する正方形の中心が一致するように供試体を載置できる。
なお、供試体載置補助治具は、台座上に設置しても良いし、図４に示すように台座の外側に設置しても良い。また、供試体載置補助治具は、熱や衝撃による変形を防ぐため、好ましくはインバー鋼材を用いて製造する。
(D) Specimen Placement Auxiliary Jig In the drying shrinkage strain measuring device used in the present invention, a specimen mounting auxiliary jig may be used in order to facilitate the mounting of the specimen on the support member. Examples of the specimen mounting auxiliary jig include two pins installed on the outside of the pedestal as shown in FIG. When, for example, a disk-shaped specimen having a diameter of 10 cm is placed on the support member of the drying shrinkage strain measuring device of FIG. 4, the specimen is placed on the support member so as to come into contact with the two pins. Then, the specimen can be placed so that the center of the specimen and the center of the square formed by the support member coincide with each other.
The specimen mounting auxiliary jig may be installed on the pedestal or may be installed outside the pedestal as shown in FIG. Further, the specimen mounting auxiliary jig is preferably manufactured using Invar steel material in order to prevent deformation due to heat or impact.
本発明で用いる乾燥収縮ひずみ測定装置は、図１〜４に示すように、２個以上のレーザー変位計、台座、および、供試体の載置を容易にするために必要に応じて供試体載置補助治具を、一体化して構成することが好ましい。この場合、レーザー変位計と台座を設置するための基盤は、熱や衝撃による変形を防ぐため、好ましくはインバー鋼材を用いて製造する。 As shown in FIGS. 1 to 4, the drying shrinkage strain measuring device used in the present invention mounts two or more laser displacement meters, a pedestal, and a specimen as necessary to facilitate mounting of the specimen. It is preferable that the placement auxiliary jig is integrally configured. In this case, the base for installing the laser displacement meter and the pedestal is preferably manufactured using Invar steel material in order to prevent deformation due to heat or impact.
２．乾燥収縮ひずみの測定と乾燥収縮ひずみの終局値の取得
本発明において乾燥収縮ひずみの測定は、まず、前記乾燥収縮ひずみ測定装置の台座上に、円板状または四角板状の供試体を載置する（供試体の載置工程）。
本発明では、（１）別の場所で乾燥している供試体を、所定の乾燥期間毎に台座上に載置して、乾燥収縮ひずみを測る方法と、（２）台座上に供試体を載置したままの状態で、供試体を乾燥して、所定の乾燥期間毎に、乾燥収縮ひずみを測る方法、のいずれも可能であるが、多数の供試体の乾燥収縮ひずみを並行して測定できるため、前記（１）の方法が好ましい。
本発明において、供試体が円板状の場合、供試体の直径は、１０〜３０ｃｍであれば、供試体の製造は容易で、また供試体の乾燥が速くなり好ましい。なお、供試体の直径は、より好ましくは１０〜２０ｃｍである。また、供試体の厚さは、５〜２０ｍｍであれば供試体は割れ難く、また供試体の乾燥がさらに速くなるため好ましい。なお、供試体の厚さは、より好ましくは６〜１８ｍｍ、さらに好ましくは７〜１５ｍｍ、特に好ましくは８〜１２ｍｍである。
また、供試体が四角板状の場合、四角板の１辺の長さは、好ましくは１０〜３０ｃｍ、より好ましくは１０〜２０ｃｍであり、さらに好ましくは、１辺の長さが１０〜３０ｃｍの正方形、特に好ましくは、１辺の長さが１０〜２０ｃｍの正方形である。１辺の長さが１０〜３０ｃｍであれば、供試体の製造は容易で、また供試体の乾燥が速くなる。また、四角板状の供試体の厚さは、好ましくは５〜２０ｍｍ、より好ましくは６〜１８ｍｍ、さらに好ましくは７〜１５ｍｍ、特に好ましくは８〜１２ｍｍである。供試体の厚さが５〜２０ｍｍであれば、供試体は割れ難く、また供試体の乾燥はさらに速くなる。
2. 2. Measurement of Dry Shrink Strain and Acquisition of Ultimate Value of Dry Shrink Strain In the present invention, in the measurement of dry shrink strain, first, a disk-shaped or square plate-shaped specimen is placed on the pedestal of the dry shrink strain measuring device. (Placement process of specimen).
In the present invention, (1) a method of placing a specimen dried in another place on a pedestal at a predetermined drying period and measuring the drying shrinkage strain, and (2) placing the specimen on the pedestal. It is possible to measure the drying shrinkage strain of a large number of specimens in parallel by drying the specimen while it is still placed and measuring the drying shrinkage strain at predetermined drying periods. Therefore, the method (1) described above is preferable.
In the present invention, when the specimen is in the shape of a disk and the diameter of the specimen is 10 to 30 cm, it is preferable that the specimen is easy to manufacture and the specimen dries quickly. The diameter of the specimen is more preferably 10 to 20 cm. Further, if the thickness of the specimen is 5 to 20 mm, the specimen is not easily cracked and the specimen dries even faster, which is preferable. The thickness of the specimen is more preferably 6 to 18 mm, further preferably 7 to 15 mm, and particularly preferably 8 to 12 mm.
When the specimen is in the shape of a square plate, the length of one side of the square plate is preferably 10 to 30 cm, more preferably 10 to 20 cm, and even more preferably 10 to 30 cm on one side. A square, particularly preferably a square with a side length of 10 to 20 cm. If the length of one side is 10 to 30 cm, the specimen can be easily manufactured and the specimen can be dried quickly. The thickness of the square plate-shaped specimen is preferably 5 to 20 mm, more preferably 6 to 18 mm, still more preferably 7 to 15 mm, and particularly preferably 8 to 12 mm. If the thickness of the specimen is 5 to 20 mm, the specimen is hard to crack and the specimen dries even faster.
本発明における乾燥収縮ひずみの測定では、レーザー変位計を用いて供試体の周囲の側面にレーザーを照射して、レーザー変位計と供試体の周囲の側面の間の距離を測定することにより、供試体の乾燥収縮ひずみを測る。そして、レーザー変位計と供試体の周囲の側面の間の距離が一定に達した時点の供試体の乾燥収縮ひずみを、該供試体の乾燥収縮ひずみの終局値として取得する（乾燥収縮ひずみの終局値の取得工程）。ここで、レーザー変位計と供試体の周囲の側面の間の距離が一定に達した時点とは、7日間での当該距離の変化量が０．００１ｍｍ以下になった時点を意味する。
なお、本発明における乾燥収縮ひずみの測定では、乾燥収縮ひずみの測定間隔は任意であるが、乾燥収縮ひずみの終局値を早期に得るためや、測定の手間を軽減するため、好ましくは乾燥期間１〜１０日毎、より好ましくは乾燥期間１〜７日毎である。
In the measurement of drying shrinkage strain in the present invention, a laser displacement meter is used to irradiate the peripheral side surface of the specimen with a laser, and the distance between the laser displacement meter and the peripheral side surface of the specimen is measured. Measure the drying shrinkage strain of the specimen. Then, the drying shrinkage strain of the specimen at the time when the distance between the laser displacement meter and the side surface around the specimen reaches a certain value is acquired as the ultimate value of the drying shrinkage strain of the specimen (the ultimate drying shrinkage strain). Value acquisition process). Here, the time when the distance between the laser displacement meter and the side surface around the specimen reaches a constant means the time when the amount of change in the distance in 7 days becomes 0.001 mm or less.
In the measurement of the drying shrinkage strain in the present invention, the measurement interval of the drying shrinkage strain is arbitrary, but in order to obtain the final value of the drying shrinkage strain at an early stage and to reduce the labor of measurement, the drying period 1 is preferable. Every 10 to 10 days, more preferably every 1 to 7 days of drying period.
３．乾燥収縮ひずみの推定方法
本発明の乾燥収縮ひずみの推定方法は、前記（Ａ）および（Ｂ）の工程を経て取得した乾燥収縮ひずみの終局値に、表１に記載のセメントの種類に応じて選択した係数を乗じて得た値を、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した、乾燥期間６か月における乾燥収縮ひずみの値として推定する方法である。
本発明の推定方法によれば、図５に示すとおり、ＪＩＳ Ａ １１２９−１〜３に準拠して測定した乾燥期間６か月におけるセメント質硬化体の乾燥収縮ひずみの値、特に、圧縮強度が１８Ｎ／ｍｍ２以上のセメント質硬化体の乾燥収縮ひずみの値を、１００日以内という短期間で精度よく推定できる。
また、本発明の乾燥収縮ひずみの推定方法が適用できるセメント質硬化体の種類は、特に限定されず、普通コンクリートのほか、収縮低減剤または膨張材を含むコンクリート（図５参照）、速硬型コンクリート、軽量コンクリート、および高強度コンクリート等のセメント質硬化体にも適用できる。
また、コンクリートが収縮低減剤を含む場合、収縮低減剤の単位量は、好ましくは１２ｋｇ／ｍ３以下、より好ましくは９ｋｇ／ｍ３以下、さらに好ましく６ｋｇ／ｍ３以下であり、また、コンクリートが膨張材を含む場合、膨張材の単位量は、好ましくは３０ｋｇ／ｍ３以下、より好ましくは２５ｋｇ／ｍ３以下、さらに好ましく２０ｋｇ／ｍ３以下である。
また、セメントが高炉セメントである場合、該セメントは、好ましくは高炉セメントＡ種またはＢ種である。セメントがシリカフュームを含む場合、セメント中のシリカフュームの含有率は、好ましくは２０質量％以下である。
3. 3. Method for estimating dry shrinkage strain In the method for estimating dry shrinkage strain of the present invention, the final value of the dry shrinkage strain obtained through the steps (A) and (B) is set according to the type of cement shown in Table 1. This is a method of estimating the value obtained by multiplying the selected coefficient as the value of the drying shrinkage strain at a drying period of 6 months, which is measured according to JIS A 1129-1 to 3.
According to the estimation method of the present invention, as shown in FIG. 5, the value of the drying shrinkage strain of the cementum-hardened product during the drying period of 6 months measured in accordance with JIS A 1129-1 to 3, especially the compressive strength. The value of the drying shrinkage strain of a cementum hardened product of 18 N / mm 2 or more can be accurately estimated within a short period of 100 days or less.
The type of cemented hardened material to which the method for estimating dry shrinkage strain of the present invention can be applied is not particularly limited, and in addition to ordinary concrete, concrete containing a shrinkage reducing agent or an expanding material (see FIG. 5), and quick-hardening type. It can also be applied to hardened cement materials such as concrete, lightweight concrete, and high-strength concrete.
When the concrete contains a shrinkage reducing agent, the unit amount of the shrinkage reducing agent is preferably 12 kg / m 3 or less, more preferably 9 kg / m 3 or less, still more preferably 6 kg / m 3 or less, and the concrete When the expanding material is included, the unit amount of the expanding material is preferably 30 kg / m 3 or less, more preferably 25 kg / m 3 or less, and further preferably 20 kg / m 3 or less.
When the cement is a blast furnace cement, the cement is preferably a blast furnace cement type A or type B. When the cement contains silica fume, the content of silica fume in the cement is preferably 20% by mass or less.
以下、本発明を実施例により説明するが、本発明はこれらの実施例に限定されない。
１．使用材料
（１）セメント（太平洋セメント社製）
(i)普通ポルトランドセメント（略号：ＮＣ）
(ii)高炉セメントＢ種（略号：ＢＢ）
(iii)中庸熱ポルトランドセメント（略号：ＭＣ）
(iv)低熱ポルトランドセメント（略号：ＬＣ）
(v)フライアッシュセメントＣ種（略号：ＦＡ)
ブレーン比表面積は３３００ｃｍ２／ｇ、フライアッシュの含有率は３０質量％である。
（２）細骨材（略号：Ｓ）
山砂（表乾密度２．５６ｇ／ｃｍ３）
（３）粗骨材（略号：Ｇ）
砂岩砕石（表乾密度２．６１ｇ／ｃｍ３）
（４）水（略号：Ｗ）
水道水
（５）ＡＥ減水剤（略号：ＬＳ）
リグニンスルホン酸系ＡＥ減水剤、商品名 ポゾリスＮｏ．７０［登録商標］（ＢＡＳＦ社製）
（６）ＡＥ剤
商品名 マスターエア４０４［登録商標］（ＢＡＳＦ社製）
（７）収縮低減剤（略号：ＳＲ）
商品名 テトラガードＡＳ２１（太平洋マテリアル社製）
（８）膨張材（略号：ＥＸ）
太平洋ハイパーエクスパン（太平洋マテリアル社製）
Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to these Examples.
1. 1. Materials used (1) Cement (manufactured by Taiheiyo Cement)
(i) Ordinary Portland cement (abbreviation: NC)
(ii) Blast furnace cement type B (abbreviation: BB)
(iii) Moderate heat Portland cement (abbreviation: MC)
(iv) Low heat Portland cement (abbreviation: LC)
(v) Fly ash cement type C (abbreviation: FA)
The specific surface area of the brain is 3300 cm 2 / g, and the content of fly ash is 30% by mass.
(2) Fine aggregate (abbreviation: S)
Mountain sand (surface dry density 2.56 g / cm 3 )
(3) Coarse aggregate (abbreviation: G)
Sandstone crushed stone (surface dry density 2.61 g / cm 3 )
(4) Water (abbreviation: W)
Tap water (5) AE water reducing agent (abbreviation: LS)
Ligno sulfonic acid-based AE water reducing agent, trade name Pozoris No. 70 [Registered Trademark] (manufactured by BASF)
(6) Air Entrainment Product Name Master Air 404 [Registered Trademark] (manufactured by BASF)
(7) Shrinkage reducing agent (abbreviation: SR)
Product name Tetra Guard AS21 (manufactured by Pacific Materials)
(8) Expansion material (abbreviation: EX)
Pacific Hyper Expand (manufactured by Pacific Materials)
２．乾燥収縮ひずみ測定用の供試体の作製
表２に示す配合に従い、前記の各材料を容量５０リッターのパン型ミキサに一括して投入し、２分間混練した後、混練物を内径１０ｃｍ、高さ２０ｃｍの型枠に打設し成形してコンクリートを得た。次に、該コンクリートを２０℃で１日間湿空養生した後に脱型し、さらに２０℃で７日間水中養生した。水中養生した後、コンクリートの高さ方向の中央部付近を切断して、直径１０ｃｍ、厚さ１０ｍｍの乾燥収縮ひずみ測定用の供試体を各３個作製した。
なお、ＪＩＳ Ａ １１０８「コンクリートの圧縮強度試験」に準拠して測定したコンクリートＡ、Ｄ、およびＦの材齢２８日の圧縮強度は、それぞれ４７Ｎ／ｍｍ２、４０Ｎ／ｍｍ２、および４６Ｎ／ｍｍ２であった。
2. 2. Preparation of Specimen for Dry Shrink Strain Measurement According to the formulation shown in Table 2, each of the above materials was put into a pan-type mixer having a capacity of 50 liters, kneaded for 2 minutes, and then the kneaded product had an inner diameter of 10 cm and a height of 10 cm. Concrete was obtained by casting and molding into a 20 cm mold. Next, the concrete was moist-air-cured at 20 ° C. for 1 day, then demolded, and further water-cured at 20 ° C. for 7 days. After curing in water, the vicinity of the central portion in the height direction of the concrete was cut to prepare three specimens for measuring dry shrinkage strain having a diameter of 10 cm and a thickness of 10 mm.
The compression strength of JIS A 1108 concrete was measured according to "the concrete compressive strength test" A, D, and F age of 28 days, respectively 47N / mm 2, 40N / mm 2, and 46N / mm It was 2 .
３．供試体の乾燥収縮ひずみの測定
乾燥収縮ひずみ測定用の供試体を、図１に示す乾燥収縮ひずみ測定装置の台座に固定した支持部材に、該供試体の中心と支持部材が形成する正方形の中心が一致するように載置したまま、室温２０±２℃、相対湿度６０±５％の条件で乾燥した。そして、乾燥期間７日毎に、対向する２組のレーザー変位計を用いて、レーザー変位計と供試体の周囲の側面の間の距離を測定して平均値を求め、この平均値と乾燥開始直前におけるレーザー変位計と供試体の周囲の側面の間の距離との差を、乾燥開始直前における供試体の直径で除した値を当該供試体の乾燥収縮ひずみとして算出し、さらに、この３個の供試体の乾燥収縮ひずみ（平均値）を平均して、全体の乾燥収縮ひずみを算出した。その結果を表３と図４に示す。
ただし、表３中の数値の意味は以下のとおりである。
(i）「ひずみの終局値 本発明」欄内の数値は、図１の乾燥収縮ひずみ測定装置を用いて測定した乾燥収縮ひずみの終局値を示す。
(ii）「ひずみの終局値 ＪＩＳ法」欄内の数値は、ＪＩＳ Ａ １１２９-２「モルタル及びコンクリートの長さ変化測定方法 第２部：コンタクトゲージ方法」（以下「ＪＩＳ法」という。）に準拠して測定した、乾燥収縮ひずみの終局値を示す。
(iii）「乾燥期間６か月のひずみの実測値」欄内の数値は、前記ＪＩＳ法に準拠して測定した、乾燥期間６か月における乾燥収縮ひずみの値（実測値）を示す（比較例）。
(iv）「乾燥期間６か月のひずみの推定値」欄内の数値は、実施例として、乾燥収縮ひずみの終局値に、表１から供試体中のセメントの種類に応じて選択した係数を乗じて得た値（推定値）を示す（実施例）。
3. 3. Measurement of Dry Shrink Strain of Specimen The center of the specimen and the center of the square formed by the support member on the support member fixed to the pedestal of the dry shrinkage strain measuring device shown in FIG. It was dried under the conditions of room temperature of 20 ± 2 ° C. and relative humidity of 60 ± 5% while being placed so as to match. Then, every 7 days of the drying period, the distance between the laser displacement meter and the side surface around the specimen is measured using two sets of opposing laser displacement meters to obtain an average value, and this average value and immediately before the start of drying are obtained. The difference between the distance between the laser displacement meter and the side surface around the specimen in 1) was divided by the diameter of the specimen immediately before the start of drying, and the value was calculated as the drying shrinkage strain of the specimen. The overall drying shrinkage strain was calculated by averaging the drying shrinkage strains (average values) of the specimens. The results are shown in Table 3 and FIG.
However, the meanings of the numerical values in Table 3 are as follows.
(i) Ultimate value of strain The numerical value in the column of "the present invention" indicates the ultimate value of dry shrinkage strain measured by using the dry shrinkage strain measuring device of FIG.
(ii) The numerical value in the "Ultimate value of strain JIS method" column is described in JIS A 1129-2 "Mortar and concrete length change measurement method Part 2: Contact gauge method" (hereinafter referred to as "JIS method"). The final value of the drying shrinkage strain measured according to the above is shown.
(iii) The numerical value in the "measured value of strain with a drying period of 6 months" indicates the value (measured value) of the drying shrinkage strain with a drying period of 6 months measured in accordance with the JIS method (comparison). Example).
(iv) For the numerical value in the "Estimated value of strain with a drying period of 6 months" column, as an example, the coefficient selected from Table 1 according to the type of cement in the specimen is used as the final value of the drying shrinkage strain. The value (estimated value) obtained by multiplying is shown (Example).
表３に示すように、本発明によれば、乾燥収縮ひずみの終局値に、供試体中のセメントの種類に応じて係数を乗じるだけで、ＪＩＳ法に準拠して測定した乾燥期間６か月の乾燥収縮ひずみの値を、誤差が３．１％以内という高い精度で、労せず早期に推定できる。また、本発明の高い推定精度はセメントの種類に依らないため、汎用性が高い。 As shown in Table 3, according to the present invention, the drying period is 6 months, which is measured in accordance with the JIS method by simply multiplying the final value of the drying shrinkage strain by a coefficient according to the type of cement in the specimen. The value of the drying shrinkage strain can be estimated at an early stage without any effort with high accuracy with an error of 3.1% or less. Moreover, since the high estimation accuracy of the present invention does not depend on the type of cement, it is highly versatile.
１ 供試体
２ 台座
４ レーザー変位計（ただし、黒色の矢印はレーザーを示す。）
５ 支持部材
1 Specimen 2 Pedestal 4 Laser displacement meter (However, the black arrow indicates the laser)
5 Support member
Claims (5)
（Ａ）２個以上のレーザー変位計、乾燥収縮ひずみ測定用の供試体を支持するための正三角形の３つの頂点または正方形の４つの頂点を形成するように配置してなる支持部材、および、該支持部材の一部を埋設してなる台座、を少なくとも含む、乾燥収縮ひずみ測定装置の前記支持部材上に、円板状または四角板状の供試体の中心が、前記支持部材が形成する正三角形または正方形の中心と一致するように載置する、供試体の載置工程
（Ｂ）該供試体の周囲の側面に、レーザー変位計からレーザーを照射して、レーザー変位計と供試体の周囲の側面の間の距離を測定し、該距離が一定に達した時点の供試体の乾燥収縮ひずみを、該供試体の乾燥収縮ひずみの終局値として取得する、乾燥収縮ひずみの終局値の取得工程
［表１］
JIS A 1129-1, a value obtained by multiplying the final value of the drying shrinkage strain obtained through the steps (A) and (B) below by a coefficient selected according to the type of cement shown in Table 1. A method for estimating dry shrinkage strain, which is estimated as a value of dry shrinkage strain at a drying period of 6 months, measured according to JIS A 1129-2 or JIS A 1129-3.
(A) Two or more laser displacement meters, a support member arranged so as to form three equilateral triangle vertices or four square vertices for supporting a specimen for measuring dry shrinkage strain, and On the support member of the drying shrinkage strain measuring device including at least a pedestal formed by burying a part of the support member, the center of the disk-shaped or square plate-shaped specimen is formed by the support member. Placement step of specimen to be placed so as to coincide with the center of a triangle or square (B) Around the laser displacement meter and specimen by irradiating the side surface around the specimen with a laser from a laser displacement meter. The step of acquiring the ultimate value of the drying shrinkage strain, which measures the distance between the side surfaces of the specimen and acquires the drying shrinkage strain of the specimen when the distance reaches a certain value as the ultimate value of the drying shrinkage strain of the specimen. [Table 1]
The method for estimating dry shrinkage strain according to any one of claims 1 to 4, wherein the specimen is dried while the specimen is still placed on the support member.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012107994A (en) * | 2010-11-17 | 2012-06-07 | Taiheiyo Cement Corp | Estimation method of drying shrinkage strain of concrete to which shrinkage suppressing material is added |
| JP2014020866A (en) * | 2012-07-17 | 2014-02-03 | Sumitomo Osaka Cement Co Ltd | Method for early estimating concrete drying shrinkage strain |
| JP2018173400A (en) * | 2017-01-16 | 2018-11-08 | 太平洋セメント株式会社 | Drying shrinkage strain measuring device, drying shrinkage measuring method, and drying shrinkage estimation method |
| JP2018200293A (en) * | 2017-05-26 | 2018-12-20 | 太平洋セメント株式会社 | Dry shrinkage distortion measurement device, dry shrinkage distortion measurement method, and dry shrinkage distortion estimation method |
| JP2019020306A (en) * | 2017-07-19 | 2019-02-07 | 太平洋セメント株式会社 | Method for predicting final value of drying shrinkage deformation of concrete |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012107994A (en) * | 2010-11-17 | 2012-06-07 | Taiheiyo Cement Corp | Estimation method of drying shrinkage strain of concrete to which shrinkage suppressing material is added |
| JP2014020866A (en) * | 2012-07-17 | 2014-02-03 | Sumitomo Osaka Cement Co Ltd | Method for early estimating concrete drying shrinkage strain |
| JP2018173400A (en) * | 2017-01-16 | 2018-11-08 | 太平洋セメント株式会社 | Drying shrinkage strain measuring device, drying shrinkage measuring method, and drying shrinkage estimation method |
| JP2018200293A (en) * | 2017-05-26 | 2018-12-20 | 太平洋セメント株式会社 | Dry shrinkage distortion measurement device, dry shrinkage distortion measurement method, and dry shrinkage distortion estimation method |
| JP2019020306A (en) * | 2017-07-19 | 2019-02-07 | 太平洋セメント株式会社 | Method for predicting final value of drying shrinkage deformation of concrete |
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