An Experimental Study for Improving the Durability

of Concrete Bridge Decks

2009. 9. 25

Expressway & Transportation Research Institute, Korea Expressway Corporation

Jinwon Suh

Damage in Bridge Decks1

Phase I Study : HPC for Deck 2

Field Application of HPC Deck4

Phase Study : HPC for DeckⅡ3

Conclusions5

Presentation Outline

1 Damage in Bridge Decks

Concrete Bridge Deck

- Exposure to vehicle loads and environmental attacks

- Frequent failure compared with other bridge members

- Bridge deck deterioration is major bridge maintenance problem

Deck Failure

TV Newspaper

Damages in Concrete Bridge Deck

Water & Salt Infiltration

Top PartDamage

Overlay Defi-ciency

Deep Dam-age Failure

Crack

Pothole

Leakage

Efflorescence on Bottom

Efflorescence on Overlay

Scaling under Overlay

Segregation

Damage un-der Rebar

Punching Out

Staying Water

2 Phase I Study : HPC for Deck

Concrete Mix Design

Classifica-tion

Ratio of Binder (%)Note

Cement Fly Ash Silica Fume

Granulated Blast Furnace

SlagOPC 100% - - -

FA 80% 20% - -

FS 76% 20% 4% -

BS 60% - - 40%

CompressiveStrength

Gmax

(mm)Slump(cm)

Air Content(%) Note

27 MPa35 MPa 25 13±2.5 6.5±1.0

Parameter for HPC Mix

Binder Proportions

Classification W/B(%)

S/A(%)

Water(kg/m3)

Binder(kg/m3)

FineAgg.

(kg/m3)

Coarse Agg.

(kg/m3)

SuperPlasticizer

(kg/m3)Cement FlyAsh

SilicaFume

Blast-furnace

Slag

27MPa

OPC 42.2 42.5 154 365 - - - 774 1059 2.19

FA 41.4 42.4 151 292 73 - - 766 1044 2.19

FS 42.2 42.5 152 272 72 14 - 765 1043 2.15

BS 42.3 42.5 150 213 - - 142 777 1060 2.13

35MPa

OPC 35.6 38.9 155 436 - - - 684 1083 2.62

FA 35.1 38.9 153 349 87 - - 674 1067 2.62

FS 35.8 38.9 154 327 86 17 - 672 1064 2.58

BS 34.1 38.7 151 252 - - 168 689 1091 2.52

Concrete Mix Design

Test Items and Methods

Items Standard Age Note

FRESH

Slump KS F 2402 After mixing 　

Air Content KS F 2401 After mixing 　

Cracking Tendency AASHTO DesignationPP. 34-99 28 days O-Ring Test

Length Change KS F 2424 12 weeks

HARDENED

Compressive Strength KS F 2405 3,7,28,56,90 days 　

Freezing-ThawingResistance KS F 2456 Every 30 cycles 300cycles

Type A

Chloride PenetrationResistance

KS F 2711 28, 56, 90 days RCPT

KS F 4930 for 40 days Ponding Test

Scaling Resistance ASTM C 672 50 cycles Visual Inspection

Abrasion Test JIS K 7204 28 days

Air Void of Hardened Con-crete ASTM C 642 After 28 days

Absorption Ratio KS F 2518 After 28 days

Compressive Strength

• The long-term compressive strength of mixes with admixtures were higher than that of OPC

27MPa 35MPa

3days 7days 28days 56days0

10

20

30

40

50

60

OPC FA FS BS

Com

pres

sive

Str

engt

h (M

Pa)

3days 7days 28days 56days0

10

20

30

40

50

60

OPC FA FS BS

Com

pres

sive

Str

engt

h (M

Pa)

Free Shrinkage (Length Change)

• Length changes of 35MPa mixes were larger than those of 27MPa.• FA and FS Mixes with fly ash were less than OPC and BS Mixes.

27MPa 35MPa

1 2 3 4 6 812

weeks

-7

-6

-5

-4

-3

-2

-1

0

OPC FA FS BS

Leng

th C

hang

e ra

tio (×

10-

4)

1 2 3 4 6 8 12 weeks

-7

-6

-5

-4

-3

-2

-1

0

OPC FA FS BSLe

ngth

Cha

nge

ratio

(× 1

0-4)

Crack Resistance (O-Ring Test)

< Cracks occur >

27MPa : BS(10.4day)

35MPa : OPC(17.6day), BS(8.7day)

<No crack until 28day>

27MPa : OPC, FA,FS

35MPa : FA, FS

Freezing-Thawing Resistance

• The higher compressive strength increased the freezing-thawing resistance • The admixture type did not have significant effect on the freezing-thawing resistance

0 30 60 90 120 150 180 210 240 270 300 33075

80

85

90

95

100

OPCFAFSBS

Freezing-thawing cycles

Rel

ativ

e dy

nam

icm

odul

us o

f ela

stic

ity(%

)

0 30 60 90 120 150 180 210 240 270 300 33075

80

85

90

95

100

OPCFAFSBS

Freezing-thawing cyclesR

elat

ive

dyna

mic

mod

ulus

of e

last

icity

(%)

27MPa 35MPa

Scaling Resistance

• The strength of con-

cretes did not have signif-

icant effect on the scaling

resistance .

• Mixes with ground gradu-

ated blast furnace slag

were better than other

mixes.

Classification Survey Result Rating

27

MPa

OPC overall scaling, aggregate exposing III

FA scaling in the center, aggregate exposing II

FS aggregate exposing at the center, partially scaling II

BS partially scaling and exposing aggregate I

35

MPa

OPC overall scaling and exposing aggregate III

FA overall scaling and exposing aggregate III

FS aggregate exposing at the center, partially scaling II

BS partially scaling and exposing aggregate II

Rapid Chloride Permeability Test• Compressive strength did

not have much effect on the

chloride ion penetration re-

sistance.

• Ground graduated blast fur-

nace slag and silica fume

improved the chloride ion

penetration resistance.

• Using admixtures was more

effective than increasing

strength.

28 56 90 days0

500

1,000

1,500

2,000

2,500

3,000OPC FA FS BS

Char

ge P

asse

d (C

)

Low

VeryLow

Negligible

Moderate

28 56 90 days0

500

1,000

1,500

2,000

2,500

3,000OPC FA FS BS

Char

ge P

asse

d (C

)

Low

VeryLow

Negligible

Moderate

27MPa

35MPa

Chloride Ponding Test

OPC-27 8.2mm

FA-275.4mm

FS-274.1mm

BS-273.5mm

OPC-355.1mm

FA- 354.2mm

FS- 354.0mm

BS- 353.2mm

Penetration Depth of Chloride

Summary of Phase I Study

ClassificationCom-

pressive Strength

Length Change

Freeze-Thaw Resis-tance

Chloride Ion

Penetra-tion

Scaling Resis-tance

Penetra-tion

depth

Abra-sion Test

Crack-ing Ten-dency

27Mpa

OPC O △ O △ △ △ O O

FA O O O △ O △ O O

FS O O O O O O O O

BS O △ O O O O O ×

35MPa

OPC O △ O O O △ O ×

FA O △ O O O O O O

FS O △ O O O O O O

BS O △ O O O O O ×

Conclusions of Phase I Study

In order to improve the durability of concrete ,

Increasing compressive strength of concrete

by using the more amount of cement did not

have significant effect

Using admixtures were even more effective

Ground granulated blast furnace slag : improve the chloride ion penetration resistance and scaling

resistance performance reduce the crack resistance performance

Fly ash : increase the crack resistance performance did not much affect the chloride ion penetration resistance

and scaling resistance performance

In order to improve the durability and the crack resistance,

using ternary based binder is desirable.

Conclusions of Phase I Study

3 Phase StudyⅡ3 Phase II Study : HPC for Deck

Description of the Mixes in Phase Ⅱ

In Phase II Study, the following three binder proportion were

tested

OPC : only cement as binder

HPC(KR) : 60% cement, 30% ground granulated blast fur-

nace slag, and 10% fly ash

HPC(NY) : 74% cement, 20% fly ash, and 6% micro silica

fume (similar to concrete deck of NYDOT, USA.)

The compressive strength : 30MPa

Concrete Mix Design

Design Strength(MPa)

Gmax.

(mm) W/B Slump(cm) Air Content(%) Note

30 25 Less than 0.4 13±2.5 6.5±1.0 -

Classifica-tion

Ratio of Binder (%)Note

OPC Fly Ash Silica Fume

Granulated Blast Furnace

SlagOPC 100% - - -

HPC(KR) 60% 10% - 30%

HPC(NY) 74% 20% 6% - NY-DOT

Parameter for HPC

Binder Proportions

Classification W/B(%)

S/A(%)

Water(kg)

Unit Content of Binder(kg/m3)FineAgg.

(kg/m3)

Coarse Agg.

(kg/m3)

SuperPlasticizer

(kg/m3)Cement FlyAsh

Blast-furnace

SlagSilicaFume

30MPa

OPC 40.0 42.6 158 395 - - - 746 1037 2.37

HPC(KR) 38.4 40.4 159 249 41 124 - 691 1051 2.48

HPC(NY) 40.0 40.4 164 301 81 - 24 683 1038 2.44

Concrete Mix Design

Compressive Strength

3 7 28 56 90 days0

10

20

30

40

50

60OPC HPC(KR) HPC(NY)

Com

pres

sive

Stre

ngth

(MPa

)

Crack Resistance

OPC HPC(KR), HPC(NY)

Age 10days -> 1st crack occurred

Age 28days -> Total 8 hair-cracks occurred

No crack until 28days

0 30 60 90 120 150 180 210 240 270 300 330 75

80

85

90

95

100OPC HPC(KR) HPC(NY)

Freezing-thawing cycles

Rel

ativ

e dy

nam

icm

odul

us o

f ela

stic

ity(%

)

Freezing-Thawing Resistance

80

79

76

Scaling Resistance

Rate 2

Rate 1

OPC

50cycles : 0.217kg/m2

100cycles : 0.339kg/m2

HPC(KR)

50cycles Weight Losses : 0.176kg/m2

100cycles Weight Losses : 0.326kg/m2

Rate 2

HPC(NY)

50cycles : 0.273kg/m2

100cycles : 0.367kg/m2

28 56 90 days0

500

1,000

1,500

2,000

2,500

3,000

OPC HPC(KR) HPC(NY)

Cha

rge

Pass

ed (C

)

Rapid Chloride Permeability Testing

Low

VeryLow

Negligible

Moderate

Penetration Depth of Chloride

OPC

7.3mm

3.6mm

HPC(KR)

4.5mm

HPC(NY)

To improve the durability of concrete, The ternary binders(HPC(KR), HPC(NY)) were very effective in

Improving the durability of concrete . The durability performance of HPC(KR) mix was similar to that

of HPC(NY) Micro silica fume is very expensive because it is not produced in

Korea. Ground granulated blast furnace slag and fly ash are not expen-

sive The HPC(KR) was selected the best mixture for bridge deck

Conclusions of the Phase Ⅱ Study

4 Field Application

Field Application

Test Bridge

Lane Name SuperStructure

Length(m) Width(m) Deck

Area(m2) Note

HonamExpressway Pre-flex Girder 30.0 13.0 390 -

Classification W/B(%)

S/A(%)

Water(kg)

Unit Content of Binder(kg/m3)FineAgg.

(kg/m3)

Coarse Agg.

(kg/m3)

SuperPlasticizer

(kg/m3)Cement FlyAsh

Blast-furnace Slag

30MPa

HPC37.7 39.0 154 245 41 123 666 1050 2.6

Concrete Mix Design

Construction Process

Concrete Placement

Waterproof by Sealer

Wet Curing

Follow-up Survey (after 8 months)

Compressive Strength

28days 56days 90days0

10

20

30

40

50

60OPC(lab) HPC(lab) HPC(site)

Com

pres

sive

Stre

ngth

(MPa

)

Crack Resistance

HPC(lab) : No Crack until age 56days

OPC(lab) : 1st Crack age 10days

HPC(site) : No Crack until age 56days

Freezing-thawing Resistance

0 30 60 90 120 150 180 210 240 270 300 330 75.0

80.0

85.0

90.0

95.0

100.0

OPC(lab) HPC(lab) HPC(site)

Freezing-thawing cycles

Rel

ativ

e dy

nam

icm

odul

us o

f ela

stic

ity(%

)

Rapid Chloride Permeability Test

28days 56days 90days0

500

1,000

1,500

2,000

2,500

3,000OPC(lab) HPC(lab) HPC(site)

Cha

rge

Pass

ed (C

)

Low

VeryLow

Negligible

Moderate

Comparison of Test Results

Test Items Standard OPC(lab) HPC(lab) HPC(site) Note

Air Content(%) KS F 2402 5.4 5.9 5 6∼ 　

Compressive Strength(MPa) KS F 2405 34.5/42.0/49.2 35.0/47.9/52.5 42.7/47.1/50.1 Age

28/56/90days

Cracking Tendency ASTM A 501 1st Crack at Age 10 days No Crack No Crack 　 Age 56days

Freeze-Thaw Resistance(%) KS F 2456 78.7 80.4 81 84∼ Type A

300cycles

Scaling Resistance ASTM C 672 1 1 0 1∼ 　

RCPT ASTM C 1202AASHTO T259

Moderate Very Law Very Law Age 28days

Law Very Law Very Law Age 56days

Law Very Law Very Law Age 90days

Air SpacingFactor(mm) ASTM C 642 0.26 0.23 0.29 　

5 Conclusions

Conclusions

In order to improve the durability of concrete ,

Increasing compressive strength of concrete

by using the more amount of cement did not

have significant effect

Using admixtures were even more effective

Ground granulated blast furnace slag : improve the chloride ion penetration resistance and scaling

resistance performance reduce the crack resistance performance

Fly ash : increase the crack resistance performance did not much affect the chloride ion penetration resistance

and scaling resistance performance

In order to improve the durability and the crack resistance,

using ternary based binder is desirable.

Conclusions of Phase I Study

Conclusions

The developed HPC with ternary based binder for bridge deck,

The binder proportion was composed of 60% cement, 30%

ground granulated blast furnace slag, and 10% fly ash.

No problem was found under the experimental field construction

and in follow-up survey until 8 months from the placement of

HPC bridge deck.

The compressive strength and durable characteristics were

equal or better than the laboratory test results.

In other to reduce the Life Cycle Cost, the developed HPC could

be used in Korea.

Thank You!!