Performance deterioration of

hardened cement materials due

to Freeze-Thaw cycles

Hokkaido University

Katsufumi HASHIMOTO1

BackgroundsBackgrounds-Factors and Key words on Durability-

BendingBending

TensionTension

CompressionCompression

ShearShear

LCMLCM

PredictionPrediction

FatigueFatigue

CracksCracks Pore StructurePore Structure

Pore continuityPore continuity

ConstructionConstruction

DefectDefect

ReinforcementReinforcement

CorrosionCorrosion

ScenariosScenarios

LCCLCC

2

ByBy--ProductsProductsFly AshFly Ash

Blast Furnace SlagBlast Furnace Slag

AggregatesAggregates

Pore continuityPore continuity

Threshold Pore SizeThreshold Pore Size

Mercury Intrusion Mercury Intrusion PorosimeterPorosimeter

XX--ray CTray CTChlorideChloride

SulfateSulfate

AcidAcid

Hydration productsHydration products

AntiAnti--Freezing AgentsFreezing Agents

Structural, material and chemical properties

should be comprehensivelycomprehensively considered on

Maintenance system of concrete structure.

BackgroundsBackgrounds-Deterioration due to Freeze-Thaw Cycles-

The deterioration of concrete under the effect

freeze-thaw cycles has been a problem

especially in cold regions.

3

Anti-freezing agents

Air entraining agents

PurposesPurposesof this study

1 Influence of Anti-Freeze Agents on

Freeze-Thaw Cycles

2 Pore structure and permeability change due to

Investigation on hydration products by TG-DTA and XRD

4

2 Pore structure and permeability change due to

Freeze-Thaw Cycles

3 Mechanical Performance Deterioration due to

Freeze-Thaw Cycles

Investigation on Pore structure by X-ray CT and Diffusion coefficient

Investigation on Tensile Softening Behavior

Experimental ProcedureExperimental Procedureof this study

Mix Proportion and CuringMix Proportion and CuringCement: Ordinary Portland Cement

W/C: 0.5 (Mortar and Cement Paste)

S/C: 1.0

Curing: 20oC for 28days

Air entraining agents: 0.4 wt% of cement

Anti-Freezing agents: NaCl, CaCl2, CH3COOK and CMA(Calcium Magnesium

5

2 3

Acetate)

Preparation of the Preparation of the mesomeso--scale specimensscale specimens(Taito Miura and Yasuhiko Sato, 2010)

5mm30mm

70mm

40mm

40mm

160mm

Experimental ProcedureExperimental Procedureof this study

Temperature History (0, 5, 10, 20, 50, 100 cycles)Temperature History (0, 5, 10, 20, 50, 100 cycles)

20℃

-20℃

20℃

-20℃

B. 1/2 of RILEM CIF/CDFA. RILEM CIF/CDF

6

-20℃

1h 5h 8h 12h

-20℃

30min 150min 4h 6h

20℃

-20℃

20min 100min160min 4h

20℃

-20℃

10min 50min 80min 2h

D. 1/6 of RILEM CIF/CDFC. 1/3 of RILEM CIF/CDF

A. RILEM CIF/CDF

Experimental ProcedureExperimental Procedureof this study

Temperature History (0, 5, 10, 20, 50, 100 cycles)Temperature History (0, 5, 10, 20, 50, 100 cycles)

20℃

-20℃

B. 1/2 of RILEM CIF/CDF

20℃

-20℃

E. Cycles in this study

20℃

C. 1/3 of RILEM CIF/CDF

7

D. 1/6 of RILEM CIF/CDF

-20℃

1h 5h 8h 12h

-20℃

30min 150min 4h 6h

20℃

-20℃

20min 100min160min 4h

20℃

-20℃

10min 50min 80min 2h

-20℃

1h 5h 9h 13h

Progresses and Future PlansProgresses and Future Plansof this study

1 Influence of Anti-Freeze Agents on

Freeze-Thaw Cycles

Measurement ItemsMeasurement Items

Ca(OH)2Monosulfate, Ettringite, Friedel’s salt

AFm

AFt

8

Monosulfate, Ettringite, Friedel’s salt

Total chloride, Soluble Chloride

OHCaClOAlCaOOHCaSOOAlCaO22322432

123123 ⋅⋅⋅→⋅⋅⋅

( ) NaOHCaClOHCaNaCl 2222+→+

OHCaClACOHACCaCl223232

1010 ⋅⋅→++

OHCaSOACOHACCaSO243234

323323 ⋅⋅→++

1.Disappearance of Monosulfate and Formation of Friedel’s salt

2.Disappearance of Ca(OH)2

3.Formation of Fridel’s (isolation of C3A and CaSO4 from Monosulfate)

4.Formation of Ettringite

Progresses and Future PlansProgresses and Future Plansof this study

1 Influence of Anti-Freeze Agents on

Freeze-Thaw Cycles

Modeling of Chloride Ion Movement

at the Surface Layer of Hardened Concrete (Maruya, 1998)

Chloride ion binding capacityChloride ion binding capacity

9

at the Surface Layer of Hardened Concrete (Maruya, 1998)Free chloride, Bound chloride, Friedel’s salt, Adsorbed chloride

totfixed CC ⋅=αfixedtotfree CCC −=

( )totCf=α

Cl- : Free

Cl- : Adsorbed

Cl : Solid phaseFixed

Cl- Cl-

Cl-

Cl- Cl-

Cl Cl

Cl

In the case of concrete structure in marine and cold environment,

it is necessary to know the chloride Ion movement and biding

capacity at the surface layer of hardened concrete.

nfreeSol CC ⋅= β

freeC

fixedCTotal totC

SolC : Soluble Chloride

Progresses and Future PlansProgresses and Future Plansof this study

2 Pore structure and permeability change due to

Freeze-Thaw Cycles

Non AE Mortar

(Initial)

AE Mortar

(Initial)

Measurement Items (XMeasurement Items (X--ray CT)ray CT)

Air Void: 3.9%

Air Void Spacing Factor: 272um

Air Void: 8.7%

Air Void Spacing Factor: 159um

(Initial) (Initial)

10

Progresses and Future PlansProgresses and Future Plansof this study

2 Pore structure and permeability change due to

Freeze-Thaw Cycles

Measurement Items (Mercury Intrusion Measurement Items (Mercury Intrusion ProsimeterProsimeter))Evaluation of Continuous Pore Structure and Diffusion Coefficient of

Cementitious Materials (Hashimoto, et al, 2010)

Depressurization

Pore size

Cumulative pore volume

Pressurization

Cumulative pore volumeDepressurization

Low connectivityHigh connectivity

11

Pressurization

Depressurization

Pore size

Progresses and Future PlansProgresses and Future Plansof this study

2 Pore structure and permeability change due to

Freeze-Thaw Cycles

Measurement Items (Chloride ion Diffusivity)Measurement Items (Chloride ion Diffusivity)New Test Methods for Measuring Strength and Chloride Ion Diffusion

Coefficient of Minute Region in Concrete (Otsuki, et al, 2004)

12

NaCl

5 wt%

Ca(OH)2Saturated

5mm

5mm

Epoxy resin

Detecting cellUn-detecting cell5mm

It is still not clear that pore structure change due to

Freeze-Thaw cycles influences on Permeability of Cl-.

Progresses and Future PlansProgresses and Future Plansof this study

3 Mechanical Performance Deterioration due to

Freeze-Thaw Cycles

Measurement Items (Tensile Softening)Measurement Items (Tensile Softening)Evaluation of tensile softening behavior of cement-paste and mortar

deteriorated by NaCl solution (Taito Miura and Yasuhiko Sato, 2010)

13

Tensile SofteningBending Test

σ

1σ

2σ

1w

2w w

：Tensile stress

：Crack width

σw

Size：5×30×70(mm)

1w

2w

1σ

2σ

1σ

2σ

Experimental ProcedureExperimental Procedureof this study

20℃ 20℃

B. 1/2 of RILEM CIF/CDFA. RILEM CIF/CDF

3 Mechanical Performance Deterioration due to

Freeze-Thaw Cycles

14

-20℃

1h 5h 8h 12h

-20℃

30min 150min 4h 6h

20℃

-20℃

20min 100min160min 4h

20℃

-20℃

10min 50min 80min 2h

D. 1/6 of RILEM CIF/CDFC. 1/3 of RILEM CIF/CDF

Progresses and Future PlansProgresses and Future Plansof this study

A. RILEM CIF/CDF B. 1/2 of RILEM CIF/CDF C. 1/3 of RILEM CIF/CDF D. 1/4 of RILEM CIF/CDF

200

300

400

200

300

400

200

300

400

200

300

400

Strain Behavior during 10cyclesStrain Behavior during 10cycles

-500

-400

-300

-200

-100

0

100

-30 -10 10 30

-500

-400

-300

-200

-100

0

100

-30 -10 10 30

-500

-400

-300

-200

-100

0

100

-30 -10 10 30

-500

-400

-300

-200

-100

0

100

-30 -10 10 30

3.5

4

3.5

4

3.5

4

3.5

4

3.5

4

Progresses and Future PlansProgresses and Future Plansof this study

3 Mechanical Performance Deterioration due to

Freeze-Thaw CyclesTensile Softening Behavior after 10cyclesTensile Softening Behavior after 10cycles

A. RILEM CIF/CDF

B. 1/2 of RILEM CIF/CDF

C. 1/3 of RILEM CIF/CDF

D. 1/4 of RILEM CIF/CDFInitial

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1

0

0.5

1

1.5

2

2.5

3

3.5

0 0.05 0.1

Tensile stress (MPa)

Crack width (mm)

Tensile stress (MPa)

Crack width (mm)

Tensile stress (MPa)

Crack width (mm)

Tensile stress (MPa)

Crack width (mm)

Tensile stress (MPa)

Crack width (mm)

Progresses and Future PlansProgresses and Future Plansof this study

1 Influence of Anti-Freeze Agents on Freeze-Thaw Cycles

2 Pore structure and permeability change due to

Freeze-Thaw Cycles

1-1. Chemical deterioration of hardened cement materials due to anti-freezing

agents.

1-2. Influence of Freeze and Thaw cycles on chloride Ion movement and biding

capacity of hardened cement material

17

Freeze-Thaw Cycles

3 Mechanical Performance Deterioration due to Freeze-

Thaw Cycles

3-1. Tensile Softening Behavior of Mortar under Freeze-Thaw Action with Different

Temperature History

3-2. Influence of anti-freezing agents type on Tensile Softening Behavior under

Freeze and Thaw cycles

2-1. Permeability and pore structure change of mortar under Freeze and Thaw cycles

with using X-ray CT.

2-2. Influence of anti-freezing agents type on permeability under Freeze and Thaw

cycles

Thank you for your kind attentionThank you for your kind attention

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