1 laboratory of engineering for maintenance system m1 mitsuha oda experimental investigation on...
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Laboratory of engineering for maintenance systemM1 Mitsuha Oda
Experimental investigation Experimental investigation on fatigue strength reduction on fatigue strength reduction
mechanism of concrete in mechanism of concrete in waterwater
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TODAY’S TOPICSTODAY’S TOPICS
1.Background2.Experimental overview3.Result4.Additional experiment5.Conclusion6.Next plan
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1. BACKGROUND1. BACKGROUND
0 8040
Surface energy of liquid [dyn/cm]
40
70
55
Com
pres
sive
str
engt
h [N
/mm2
]
65
60
50
45
20 60
air
hexane
cyclohexane
benzyl alcohol diethyl ether
waterethanol
strength in air > in water
Strength becomes lower as surface energy of liquid becomes larger.
Ethanol is not on this line.There is not unified
explanation.
In this experiment,I focus on the inner
behavior of concrete.
Hydrate
Water analysis
水和物
水分分析
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2. EXPERIMENTAL OVERVIEW2. EXPERIMENTAL OVERVIEW
No. situationStrength test
situationS1(％
)
S2(％)
Hydrate水和物
Water analysispH
AS-1 In air Static
○
AS-2 ―
AS-3 ―
AS-4 ―
AF80-1 Fatigue 80 5 ○
AF80-2 80 5 ―
AF80-3 80 5 ―
AF80-4 80 5 ―
WS-1 In water Static
○ ○
WS-2 ― ○
WS-3 ― ○
WS-4 ― ○
WS-5 ― ○
WF80-1 Fatigue 80 5 ○ ○
WF80-2 80 5 ○ ○
WF70-1 70 5 ○ ○
WF70-2 70 5 ○ ○
WF70-3 70 5 ○ ○
In air（ Static・ 80%）In water（ Static・ 80%・ 70%）
Specimen size
φ100mm×200mm
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3-1. RESULT (strength test)3-1. RESULT (strength test)
In air In water
Static strength
18.21 15.15
S1 14.57 12.12 10.61
S2 0.91 0.76 0.76
Fatigue life
Fatiguelife
AF80-1 530 33 WF80-1
AF80-2 0 9 WF80-2
AF80-3 387 1010 WF70-1
AF80-4 82 222 WF70-2
669 WF70-3
Static strengthin air > in water
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3-2. RESULT (hydrate amount test)3-2. RESULT (hydrate amount test)
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
WF80-1
WF80-2
WF70-1
WF70-2
WF70-3
AS-1 AF80-1
WS-1
No.
Con
tent
Rat
e [%
]
Ca(OH)2 content rate
CaCO3 content rate
fatigue test in water
The tendency by the difference of test situation is not seen.
static test in air
fatigue test in air
static test in water
傾向ナシ
水中疲労 気中静的
気中疲労
水中静的
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3-3. RESULT (water analysis)3-3. RESULT (water analysis)
OH載荷割合と総 -流出量
0.0
1000.0
2000.03000.0
4000.0
5000.0
6000.0
7000.08000.0
9000.0
10000.0
0.0 20.0 40.0 60.0 80.0 100.0N/N max
流出
OH
[μg
]
WF80-1(N=33)
WF80-2(N=9)
WF70-1(N=1010)
WF70-3(N=669)
Life Ratio and Total Outflow of OH-
Out
flow
of
OH
- [μg
]
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3-3. RESULT (water analysis)3-3. RESULT (water analysis)
軸方向ひずみとOH-流出量と載荷割合の関係
0
100
200
300
400
500
600
700
800
900
0 10 20 30 40 50 60 70 80 90 100
載荷割合N/N max
軸方向ひずみ
:ε
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
総O
H- 流出量
[mg
]
軸方向ひずみ
Life Ratio
Axi
al S
trai
n
Axial Strain, Outflow of OH- and Life Ratio
Tot
al o
utfl
ow o
f O
H- [
mg]
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3-3. RESULT (water analysis)3-3. RESULT (water analysis)
軸方向ひずみとOH-流出量と載荷割合の関係
0
100
200
300
400
500
600
700
800
900
0 10 20 30 40 50 60 70 80 90 100
載荷割合N/N max
軸方向ひずみ:ε
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
総O
H- 流出量
[mg
]
軸方向ひずみ
総OH流出量
Axial Strain, Outflow of OH- and Life Ratio
Tot
al o
utfl
ow o
f O
H- [
mg]
Axi
al S
trai
n
Life Ratio
Strain increasing
Outflow increasing
1010
4. ADDITIONAL EXPERIMENT4. ADDITIONAL EXPERIMENT
porous concrete
Surface energy is important factor ?
Porous concrete have a large surface area.
Porous concrete is affected more than normal concrete
Specimen sizeφ100mm×200mm Strength test Water analysis
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4. ADDITIONAL EXPERIMENT (strength test)4. ADDITIONAL EXPERIMENT (strength test)
In air In water
Static strength 16.69 17.23
S1 13.35 13.78
S2 0.83 0.86
Fatigue life Fatigue life
PAF80-1 721 12 PWF80-1
PAF80-2 6330 122 PWF80-2
3031 PWF80-3
Static strengthin air < in water
Reduction ratenormal > porous
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4. ADDITIONAL EXPERIMENT (water analysis)4. ADDITIONAL EXPERIMENT (water analysis)
載荷割合と総流出量
0
20
40
60
80
100
120
140
160
180
200
0 0.2 0.4 0.6 0.8 1
載荷割合N/Nmax
流出
OH
- [mg]
PWF80-1(N=12)
PWF80-2(N=122)
PWF80-3(N=3031)
Life Ratio
Out
flow
of
OH
- [μg
]Life Ratio and Total Outflow of OH-
1313
4. ADDITIONAL EXPERIMENT (water analysis)4. ADDITIONAL EXPERIMENT (water analysis)
サンプルNo.
コンクリート粉末量 [g]
pH
0 0.0 6.0
1 1.0 6.5
2 2.0 6.5
3 3.0 6.5
4 4.0 6.5
5 5.0 6.5
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5. CONCLUSION5. CONCLUSION
Strength test In normal concrete, in air > in waterSurface area is not important factor.
Hydrate testDifference is not seen by the test situation.Hydrate is not so important factor.
Water analysisOutflow of OH- is increase near by crash. In short life test, outflow of OH- is not seen.This OH- is not for concrete pieces.
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6. NEXT PLAN6. NEXT PLAN
Another material Strength of metal is reduction in water, too.
Surface energy Why ethanol is distant from this line ?
Learn about previous experiment and surface energy
surface energy pore pressure viscosity, fliction etc… 0 8040
Surface energy of liquid [dyn/cm]
40
70
55
Com
pres
sive
str
engt
h [N
/mm2
]
65
60
50
45
20 60
air
hexanecyclohexane
benzyl alcohol diethyl ether
waterethanol
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Thank you forThank you for your kind attention !your kind attention !