硝酸銀溶液噴霧による硬化コンクリートの塩化物イオン浸透深さ試験方法に関する研究

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The Bulletin of Institute of Technologists, No. 8

Article

A Study on Test Method for Penetration Depth of Chloride Ions

into Hardened Concrete by Spraying AgNO

Solution

Kokoro TOBE

_{, Takehiro SAWAMOTO}

_{, Kazumasa MORIHAMA}

_,

Yusuke AOKI

_{, and Koji KAWAMATA}

*1

_{Undergraduate,}

_{Dept. of Building Technologists, Institute of Technologists}

_{Dept. of Building Technologists, Institute of Technologists}

_{Dept. of Civil and Environmental Eng.,N.I.T.Kisarazu College}

*4

_{Chuken Consultant Co.,Ltd}

Abstract The test method for penetration depth of chloride ions into hardened concrete by spraying AgNO3

solution has been applied since 1970. This test method makes use of discolored boundary between AgCl and Ag2O by spraying AgNO3 solution. However, this method has some problems. In this study,

some problems of this test method were resolved. The main conclusions are as follows. (1) The movement of discolored boundary ends passage of an hour after spraying AgNO3 solution. (2) The

content of total chloride ions at the discolored boundary is about from 2kg/m3 _{to 4kg/m}3_{. (3) Spraying}

NaOH solution before spraying AgNO3 solution is effective when the specimen is carbonated.

Key Words : Concrete, AgNO

solution, Content of chloride ion, Penetration depth, Discolored Boundary

10

Fig. 1

A

B

B

Fig. 2

Table 1

100 200mm

NaCl

10%

1

0.1mol/L

Photo. 2

15mm

10

20

Fig. 1 Conditions of concrete specimens

Atmosphere

Tide mark

Under the sea

Salt water

H.W.L

L.W.L

Photo. 1 Spray AgNO3 Solution to concrete core

Fig. 2 Test flow of this study

Chloride test Carbonation test

Split specimen

Spray distilled water Spray NaOH solution

Spray AgNO3solution

Leave specimen for 60 minutes Dry specimen with hair drier

Measurement for depth of chloride ions Measurement for depth of carbonation Spray C20OH14O4 solution

Wet condition Air-dry condition

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The Bulletin of Institute of Technologists, No. 8

Table 2

1

A

4

B

15

30

1

2

4

Photo. 2 Spray AgNO3 Solution

Photo. 5 Radiate ultraviolet rays Photo. 3 Spray distilled water

Photo. 4 SprayNaOH solution

12

4

Photo. 3

1

4

3.2

(

)

NDIS 3433

Photo. 4

1mol/L

2mol/L

6%

Photo. 5

Fig.

3

Fig. 4

Photo. 6

60

Fig. 3

Fig. 4

60

10mm

Fig. 3

1

Fig. 4

4

N-Fc60

30

Fig. 4

Fig. 3

Fig. 4

Fig. 5

Fig. 5

N-Fc60

15

Photo.

7

Fig. 4

Fig. 5

Fig. 6

Photo. 8

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The Bulletin of Institute of Technologists, No. 8

Fig. 3 Specimens dried for a week after taking out from salt 0 10 20 30 40 50 0 30 60 90 120 150 180 210 240 Passage of time min.

N-Fc60 N-Fc36 BB-Fc27 BB-Fc27 (40mm) -14 -12 -10 -8 -6 -4 -2 0 2 4 0 30 60 90 120 150 180 210 240

passage of time min. N-Fc60 N-Fc36 BB-FC27 BB-FC27 (40mm)

Fig. 4 Specimens dried for 4 months after taking out from salt water 0 10 20 30 40 50 0 30 60 90 120 150 180 210 240 Passage of time (min.)

N-Fc60 N-Fc36 BB-Fc27 BB-Fc27(40mm) -14 -12 -10 -8 -6 -4 -2 0 2 4 0 30 60 90 120 150 180 210 240

14

15

Fig. 7

Fig. 7

Fig. 5 Specimens dried for 4 months after taking out from salt water Spray distilled water in advance 0 10 20 30 40 50 0 30 60 90 120 150 180 210 240 Passage of time (min.)

N-Fc60 N-Fc36 BB-Fc27 BB-Fc27(40mm) -14 -12 -10 -8 -6 -4 -2 0 2 4 0 30 60 90 120 150 180 210 240

Passage of time (min.) N-Fc60 N-Fc36 BB-FC27 BB-FC27 (40mm)

Fig. 6 Effect of drying specimen with hair drier

0 2 4 6 8 10 12 0 15 30 45 60

Passage of time min.

Natural dry Dry with hair drier

Fig. 7 Relation between content of total chloride ions and distance from concrete surface

Spray AgNO3 solution

Photo. 7 Effect of spraying distilled water in advance N Fc60 Spray distilled water in advance

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The Bulletin of Institute of Technologists, No. 8

Table 3

60

2kg/m

_B

3kg/m

Table 3 Content of total chloride ions at discolored boundary

Photo. 10 Spray NaOH solution to carbonated specimen N Fc18

Spray AgNO3 solution Spray NaOH solution

Photo. 9 Spray AgNO3 solution and C20H14O4 solution to

carbonated specimen N Fc18

Spray C20H14O4 solution Spray AgNO3 solution

Spray distilled water in advance

Photo. 11 Effect of spraying NaOH solution in advance BB Fc36 Spray 1mol/L NaOH solution

in advance

Spray distilled water in advance

16

60

2kg/m

60

Photo. 9

Photo.

10

Fig. 8

Photo. 11

1mol/L

2mol/L

Photo. 12

Photo. 13

Photo. 12

10

Photo. 12 Before radiation ultraviolet rays by sunshine Discolored boundary by carbonation

Photo. 14 Radiate ultraviolet rays by black light Photo. 13 After radiation ultraviolet rays by sunshine Discolored boundary

by chloride ions

Discolored boundary by carbonation

Distilled water

+ AgNO3 solution 1mol/L NaOH solution + AgNO3 solution Distilled water + AgNO3 solution 2mol/L NaOH solution + AgNO3 solution

Fig. 8 Effect of spraying NaOH solution in advance BB Fc36 0

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The Bulletin of Institute of Technologists, No. 8

Photo.

14

10

(1)

60

(2)

60

(3)

2 4kg/m

(4)

(5)

1) Nobuaki Otsuki, Shigeyoshi Nagataki, Kenji Nakashita: Evaluation of AgNO3 _{Solution Spray Method for}

Measurement of Chloride Penetration into Hardened Cementitious Matrix Materials, ACI Material Journal / November-December, Title no.89-M64, pp.587-592, 1992 2)

No.42 pp.11-18 1990.12

3) Fuqiang He, Caijun Shi, Qiang Yuan, Changping Chen, Keren Zheng : AgNO3_{-based colorimetric methods for}

measurement of chloride penetration in concrete Construction and Building Materials, Volume 26, Issue 1, January,pp.1-8, 2012.1

4) M. Collepardi : Quick method to determine free and bound chlorides in concrete, RILEM International Workshop on Chloride penetration into concrete, Saint Remy-les-Chevreuse, pp. 10-16, 15-18 October ,1995 5) 35 No.1 pp.1843-1848 2013.7 6) 34 No.1 pp.832-837 2012.7 7) NDIS 3433 2018 8) Vol.32, No.1, pp.785-790, 2010 9) 28 pp.129-132, 2016