08-self consolidating concrete

8/3/2019 08-Self Consolidating Concrete

1/22

SELF CONSOLIDATING CONCRETE

Effect of Mix Design on Design and

Performance of Precast/Prestressed Girders

Rigoberto Burgueo, Ph.D.Assistant Professor of Structural Engineering

Department of Civil and Environmental Engineering

Michigan State University

BACKGROUND & MOTIVATION

Self-Consolidating Concrete (SCC): a specially proportioned

concrete that can flow easily into forms and around steel

reinforcement without segregation.

The benefits of SCC in reduced labor needs, increased rate of

production and safety, and lower noise levels have generated

great interest from the precast concrete industry.

Considerable development in SCC technology has been made

through the past decades particularly in Japan, Canada, and

Europe, and its applications have become wide spread.

SCC FRESH PROPERTY BEHAVIOR


2/22


Self-Consolidating Concrete (SCC): a specially proportioned

concrete that can flow easily into forms and around steel

reinforcement without segregation.

The benefits of SCC in reduced labor needs, increased rate of

production and safety, and lower noise levels have generated

great interest from the precast concrete industry.

Considerable development in SCC technology has been made

through the past decades particularly in Japan, Canada, and

Europe, and its applications have become wide spread.

SCC BENEFITS


Use of SCC in the US has been limited because of concerns

about design and construction issues that are perceived to

influence the structural integrity.

In spite of the rapid developments in SCC technology, most of

the work has focused on mix design development, rheology

characterization, mechanical properties, and in-situ verification.

Very limited information exists on issues related to structural

design and performance.


3/22

A. Increase paste deformability

* use of HRWR

* balanced w/c ratio

B. Reduce inter-particle friction

* low coarse aggregate volume

* use cont. graded powder

Fluidity/Deformability

A. Increase paste deformability

* use of HRWR

* balanced w/c ratio

B. Reduce inter-particle friction


* use cont. graded powder

Fluidity/Deformability

A. Reduce solids separation

* limit aggregate content

* reduce max. size aggregate

* increase cohesion & viscosity

- low w/c ratio

- use of VMA

B. Minimize bleeding

* low w/c ratio

* use of high-area powder

* increase VMA

Homogeneity/Stability

A. Reduce solids separation

* limit aggregate content

* reduce max. size aggregate

* increase cohesion & viscosity

- low w/c ratio

- use of VMA

B. Minimize bleeding

* low w/c ratio

* use of high-area powder

* increase VMA

Homogeneity/Stability

A. Enhance cohesiveness

* low w/c ratio

* use of VMA

B. Compatible flow space and

aggregate size


* low max. size aggregate

Easy Flow/Low Blockage

A. Enhance cohesiveness

* low w/c ratio

* use of VMA

B. Compatible flow space and

aggregate size


* low max. size aggregate

Easy Flow/Low Blockage

Viscosity

Deformability

High Viscosity,LowFluidity

LowViscosity,High Fluidity

Fluidity/Stability

Trade-off

Viscosity

Deformability

High Viscosity,LowFluidity

LowViscosity,High Fluidity

Fluidity/Stability

Trade-off

SCC PROPORTIONING & BEHAVIOR

SCC MIX DESIGN DEVELOPMENT

No commonly accepted procedure to proportion SCC.

Methods are bounded by two approaches:

1) High w/c ratios (e.g., 0.45) and use of HRWR and VMA.

2) Lower w/c ratios (e.g. 0.33), high use of HRWR and no VMA

Approach:Develop characteristic bounding SCC mix designs.

Mix Design w/c HRWR VMA CAC S/Pt EA

SCC-1 0.35 + less more +

SCC-2 0.40 + +/ +

SCC-3 0.45 + + +

NCC 0.40 + more less +

PCI Daniel P. Jenny Research Fellowship on Structural

Performance of PC/PS Girder Bridges using SCC

Objective:

To investigate the transfer and flexural bond length

performance of prestressing strands in pc/ps bridge girders

built using SCC to provide guidance on the construction and

design of these elements with SCC.

MSU SCC RESEARCH Part 1


4/22

MIX DESIGNS PCI Project

Constituents (lbs)

666.6906.14DELVO StabilizerSet Retardant

0913.940Rheomac VMA 358VMA

2878.496.29Glenium 3200 HESHRWR

19.080.50.210.5MB-AETM 90Air Entraining

Admixtures (oz/cwt)

0.40.450.40.40.35w/c Ratio

6%6%6%6%6%(design)Air

280315280280245Water

158014351380138013806 AAGravel

121612751426142615192 NSSand

700700700700700Type-IIICement

NCCBSCC3SCC2BSCC2ASCC1Type

Inverted Slump Flow and VSI Test

127"SCC3

0*24.5"SCC2b

0.525"SCC2a

027"SCC1

Visual

Stability

Index

Slump

Spread

Flow

* Concrete had very low flowability

FRESH PROPERTIES PCI Project


41.28SCC3

naSCC2b

23.81SCC2a

1.59SCC1

J-Ring

Value

J-Ring Test


5/22

2, 9*0.69*SCC3

na0.76SCC2b

1, 20.86SCC2a

1, 20.80SCC1

t1, t2

(sec.)

Blocking

Ratio

* Test was done too late


L-Box Test

CONSTITUTIVE PROPERTIES fc

Age Of Concrete (days)0 20 40 60 80 100 120 140

CompressiveStrength(psi)

4500

5000

5500

6000

6500

7000

7500

8000

8500

9000

9500

10000

CompressiveStrength(MPa)

30

33

36

39

42

45

48

51

54

57

60

63

66

NCCB

SCC1

SCC2A

SCC2B

SCC3

CONSTITUTIVE PROPERTIES fct

Age Of Concrete (days)

0 20 40 60 80 100 120 140

SplitTensileStr

ength(psi)

400

450

500

550

600

650

700

SplitTensileStrength(MPa)

3.00

3.25

3.50

3.75

4.00

4.25

4.50

4.75

NCCB

SCC1

SCC2A

SCC2B

SCC3


6/22

CONSTITUTIVE PROPERTIES Ec

Concrete Age (days)

0 5 10 15 20 25 30

ElasticModulus(psi)

2.6e+6

2.8e+6

3.0e+6

3.2e+6

3.4e+6

3.6e+6

3.8e+6

4.0e+6

4.2e+6

4.4e+6

4.6e+6

ElasticModulus(GPa)

18

20

22

24

26

28

30

SCC1

SCC2a

SCC2b

SCC3

NCCb

TRANSFER AND DEVELOPMENT

LENGTH OF PRESTRESSING STRANDS

2 beams per concrete mix 4 flexural bond tests per mix.

2 1/2-in. diameter strands - Stressed at ~ 0.75fu

38 ft in length.

CrossSection:

3 SCC mix designs that bound mix currentdesign approaches

1 normally consolidated concrete (NCC)mix as a control mix

SCC mix performance was to be evaluated

PRODUCTION PLAN


7/22

Casting Bed and Stressing Operation

Casting Operation with SCC Mix

Formwork Removal and Instrumentation


8/22

Prestress Release Operation

TRANSFER LENGTH EVALUATION

Strand Pull-In Concrete Strain Profile

MIX TYPE

NCCB SCC1 SCC2A SCC2B SCC3

StrandDraw-

in(in.)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

StrandDraw-in(mm)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Strand Draw-in Measurements


9/22

Average Strain Profile for SCC1 Beams

Distance Along Beam (in.)

0 10 20 30 40 50 60 70 80 90 100

ConcreteStrain

0

1e-4

2e-4

3e-4

4e-4

5e-4

Distance Along Beam (mm)

0 250 500 750 1000 1250 1500 1750 2000 2250 2500

Lt= 719 mm

(28.3 in.)

95% AMS

SCC1

Transfer Length Evaluation PCI Phase 1

MIX TYPENCCB SCC1 SCC2A SCC2B SCC3

Transferlength(in.)

0

5

10

15

20

25

30

35

40

45

Transferlength(mm)

0

100

200

300

400

500

600

700

800

900

1000

1100 Concrete Strains

Strand Draw-in

ACI / AASHTO

Transfer Length Evaluation PCI Phase 2

MIX TYPE

NCC SCC1 SCC2 SCC3

Transferleng

th(in.)

0

5

10

15

20

25

30

35

40

45

Transferlengt

h(mm)

0

100

200

300

400

500

600

700

800

900

1000

1100 Concrete Strains

Strand Draw-in

ACI / AASHTO


10/22

Transfer Length Evaluation Summary

MIX TYPE

NCC SCC1 SCC2 SCC3

Transferlength(in.)

0

5

10

15

20

25

30

35

40

45

Transferlength(mm)

0

100

200

300

400

500

600

700

800

900

1000

1100 Phase1

Phase2

Average ACI Lt = 760.98 mm (29.96 in.)

MIX TYPE

NCC SCC1 SCC2 SCC3

Transferlength(in.)

0

5

10

15

20

25

30

35

40

45

Transferlength(mm)

0

100

200

300

400

500

600

700

800

900

1000

1100 Phase1

Phase2

Average ACI Lt = 760.98 mm (29.96 in.)

DEVELOPMENT LENGTH EVALUATION

Development Length Test Setup


11/22

Failure Modes

Flexure Failure Bond-Slip/Shear Failure

Typical Response with Flexure/Bond Failure

Displacement at the section (in.)0 1 2 3 4 5 6 7 8 9 10 11

Moment(kip-ft)

0

10

20

30

40

50

60

70

80

90

Displacement at the section (mm)

0 25 50 75 100 125 150 175 200 225 250 275

Moment(KN-m)

0

10

20

30

40

50

60

70

80

90

100

110

120

SCC3-2BLda = 103.0 in.

Mn = 116.87 kN-m (86.20 k-ft)

Slip Onset

Slip @ Mn = 3.500 mm (0.137 in.)

Displacement at the section (in.)0 1 2 3 4 5 6 7 8 9 10 11

Moment(kip-ft)

0

10

20

30

40

50

60

70

80

90

Displacement at the section (mm)

0 25 50 75 100 125 150 175 200 225 250 275

Moment(KN-m)

0

10

20

30

40

50

60

70

80

90

100

110

120

SCC3-2BLda = 103.0 in.

Mn = 116.87 kN-m (86.20 k-ft)

Slip Onset

Slip @ Mn = 3.500 mm (0.137 in.)

Development Length Test Results Phase 1

ACI - 318

test

n A CI

M

M

d test

d A CI

L

L

.d expt

d A CI

L

L

SCC1 1.06 1.07 1.03SCC2A 1.11 1.09 1.04SCC2B 1.01 1.21 1.17SCC3 1.09 1.79 1.42NCCB 1.04 1.06 0.97


12/22

Development Length Test Results Phase 2

ACI - 318

test

n A CI

M

M

d test

d A CI

L

L

.d expt

d A CI

L

L

SCC1 1.06 1.10 1.05SCC2 1.02 1.04 1.03SCC3 1.05 0.93 0.84NCC 1.11 1.06 0.96

CONCLUSIONS Part 1: PCI Project

The presented studies are serving as an evaluation of SCC mix

designs on the structural performance of precast SCC elements.

SCC mix designs with moderate w/c ratios and moderate use of

HRWR and VMA behave closer to NCC mixes without any

chemical admixtures.

Transfer lengths determined by draw-in and concrete strain

measurements indicate that the ACI equation applies to SCC.

Results from flexural tests indicate that development lengths for

SCC mixes were s lightly longer than code predicted values.

CONCLUSIONS Part 1: PCI Project

The much longer development lengths found for SCC during the

PCI Phase-1 project were verified to be due to poor strand quality.

Development length tests using a pre-qualified strand, known to

have very good properties, indicated that SCC mix designs doaffect the flexural bond mechanism of prestressing strands but in

a slight manner. A more definite position by the research team is

under consideration.

SCC mix proportioning seems to have different effects on the

associated bond mechanisms controlling transfer and flexural

bond length.


13/22

MDOT/FHWA IBRC Project: Experimental Evaluation and

Field-Monitoring of Bridge Precast/Prestressed Box-Girders

made from Self-Compacting-Concrete

Objective:

To implement SCC in the precast/prestressed box beams of a

demonstration bridge and to evaluate their short- and long-

term performance against the behavior of beams from

normally consolidated concrete.

MSU SCC RESEARCH Part 2

Bridge Deck

Beam 1

Beam 2

Beam 3

Beam 4

Beam 5

Beam 6

5 @ 8'-8"49'

52'Elevation View

Plan View

M-50/US-127 Bridge Over the Grand River

Consider 3 SCC mix designs that bound current designapproaches.

Consider 1 normally consolidated concrete (NCC) mix as a

control mix.

The short-term flexure and shear performance of the SCCbeams should be verified to be equal or better than that ofthe NCC beams through full-scale testing.

The long-term performance of the SCC beams incomparison to the NCC beams to be continuouslymonitored for a year (or more?).

APPROACH


14/22

3 NCC and 3 SCC (one for each mix design) beams for

demonstration bridge

2 NCC and 6 SCC (two of each mix design) for

experimental evaluation

3 reserve NCC beams for bridge placement in case of

unsatisfactory SCC performance

Total: 17 Beams, 8 NCC and 9 SCC

BEAM PRODUCTION

44.447.752.954.1S/A Ratio (%)

Constituents (lbs)

0621Rheomac

VMAVMA

810.71215Glenium 3400HRWR

1111MBAE90Air Entraining

Admixtures (oz/cwt)

0.400.460.410.37w/c Ratio

6%6%6%6%(design)Air

280320285256Water

1,6001,4501,3501,3506 AAGravel

1,2771,3201,5131,5912 NSSand

700700700700Type-IIICement

NCCSCC3SCC2SCC1Type

MIX DESIGNS IBRC Project

Strand Bond Evaluation Mock-up Production

Fresh Property

Evaluation

MIX DESIGN EVALUATION


15/22

27"

36"

16 Prestressing Strands

0.6" diameter

5 #4 Bars

spaced at 6"

4.5"

4.5"

5"

BEAM CROSS SECTION

NCC Beam Production

Cast in two operations

Increased laborand time

BEAM PRODUCTION

SCC Beam Production

Cast in one operation

Reduced labor andtime

EXPERIMENTAL EVALUATION


16/22

Experimental evaluation was conducted atMSUs Civil Infrastructure Laboratory

Two test beams were cast for each concrete

One was to be evaluated for flexural response

Four total tests

One was to be evaluated for shear response

Four total tests

EXPERIMENTAL APPROACH

FLEXURAL EVALUATION

Test Beam

Actuator

Reaction Floor Support Block

8

50

52

21

Reaction Frame

FLEXURAL TEST SETUP


17/22

FLEXURAL FAILURE MODE

Displacement (in.)

0 1 2 3 4 5 6 7 8 9 10

Load(kip)

0

10

20

30

40

50

60

70

80

Design-Full*

Design-Reduced*

*Nominal-AASHTO 17th Ed.

NCCSCC 1SCC 2

SCC 3

P P

P P

FLEXURE TEST RESULTS

Curvature (1/in.)

0.0000 0.0001 0.0002 0.0003 0.0004

Moment(kip-ft)

0

200

400

600

800

1000

1200

1400

1600

1800

Design-Full*Design-Reduced*

*Nominal-AASHTO 17th

Ed.

NCC

SCC 1

SCC 2

SCC 3

P P

M

P P

M

FLEXURE TEST RESULTS


18/22

ACHIEVED FLEXURAL CAPACITIES

Maximum Total

Moment

(kip-ft)

Design Moment

[AASHTO]

(kip-ft)

Actual to Design

Ratio

NCC 1,649 1,499 1.10

SCC1 1,628 1,499 1.09

SCC2 1,593 1,499 1.06

SCC3 1,590 1,499 1.06

* According to AASHTO Standard Specifications 17th Ed.

*

SHEAR EVALUATION

SHEAR TEST SETUP

Reaction Frame

Actuator

Shear Deformation PanelTest

Beam

Support Block Reaction Floor

Lv22-Lv 852

NCC: Lv = 11 ftSCC: Lv = 9 ft


19/22

SHEAR FAILURE MODE

Displacement (in.)

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

Load(kip)

0

20

40

60

80

100

120

140

160

180

200For all SCC Beams: Lv= 9 ft

For NCC Beam: Lv= 11 ft

AASHTO LRFD 2nd Ed.Design Nominal Capacity[L

v=9 ft]

AASHTO LRFD 2nd

Ed.Design Nominal Capacity[Lv=11 ft]

Note: AASHTO 17th Ed.:176 kipDesign Nominal Capacity

NCC

SCC 1

SCC 2

SCC 3

LvP P

Shear SectionLv

P P

Shear Section

SHEAR TEST RESULTS

Curvature (1/in.)

0.00000 0.00005 0.00010 0.00015 0.00020

Moment(kip-ft)

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

AASHTO LRFD 2nd Ed.Design Nominal Capacity[Lv=11 ft]

AASHTO LRFD 2nd Ed.Design Nominal Capacity[Lv=9 ft]

Note: Design Nominal Capacity: 1546 kip-ft

[AASTHO 17th Ed.]

For all SCC Beams: Lv=9 ft

For NCC Beam: Lv=11 ft

NCC

SCC 1

SCC 2

SCC 3

LvP P

Shear Section

.89 MM

SHEAR TEST RESULTS


20/22

Average Shear Strain (microstrain)

0 250 500 750 1000 1250 1500 1750 2000

ShearForce(kips)

0

20

40

60

80

100

120

140

160

180

SCC1 Exp_avg

NCC Exp_avg

SCC2 Exp_avg

NCC - AASHTO-LRFD 2nd

Ed.[f'c=5500psi, Lv=11ft]

SCC3 Exp_avg

SCC - AASHTO-LRFD 2nd

Ed.[f'c=5500psi, Lv=9ft]

LvP P

Shear SectionLv

P P

Shear SectionLv

P P

Shear SectionLv

P P

Shear Section

SHEAR TEST RESULTS

ACHIEVED SHEAR CAPACITIES

Maximum Total

Shear

(kip)

Design Shear

[AASHTO]

(kip)

Actual to Design

Ratio

NCC 128 116 1.11

SCC1 159 130 1.22

SCC2 146 130 1.12

SCC3 140 130 1.08

* According to AASHTO-LRFD Simplified Section Analysis Method

*

Beams placed: 9/15/05Open to traffic: Late October

BRIDGE CONSTRUCTION


21/22

SCC 3 - Instrumented



NCC - Instrumented

NCC

NCCInstruments per Girder:

8 Vibrating Wire Strain

Gages 8 Thermocouples

FIELD MONITORING

System deployed: 12/20/05

All beams exceeded design capacities and were implementedin the demonstration bridge.

The capacities of the NCC beams were slightly higher thenthose of the SCC beams.

The different SCC mix designs were seen to have an effect onflexural displacements as well as in the shear post-crackingbehavior.

The field-monitoring program is underway and an automateddata reduction program with potential web broadcast is under

development.

CONCLUSIONS Part 2: IBRC Project

ACKNOWLEDGEMENTS

The authors are grateful for the financial and in-kind support

provided by:

PCIthrough a 2003-2004 D.P. Jenny Research Fellowship.

MDOT and FHWA through a 2005 IBRC Project.

The Premarc Corp. in-kind labor and materials

Degussa Admixtures Inc. technical support and materials

The CEE Department at Michigan State University


22/22

ACKNOWLEDGEMENTS

The authors also gratefully acknowledge the collaborating effort and

many fruitful discussions with:

Mr. Armand Atienza (Formerly with Degussa)

Mr. Doug Burnett (Formerly with Degussa)

Mr. Tom Grumbine (Premarc)

Mr. Don Logan (Stresscon)

Mr. Horacio Lopez (Premarc)

Dr. Charles Nmai (Degussa)

Mr. Fernando Roldan (Premarc)

Mr. Roger Till (MDOT)

Mr. Chad Woodward (Degussa)

ACKNOWLEDGEMENTS

The experimental work for the presented projects was conducted at

MSUs Civil Infrastructure Laboratory. The work could not have

been possible with the aide and assistance of its staff and student

researchers, including:

Mr. David Bendert

Mr. James Brenton

Mr. Steven Franckowiak

Mr. Mahmoodul Haq

Mr. Siavosh Ravanbakhsh

08-self consolidating concrete

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