2007 Louisiana

Transportation Engineering

Conference

Baton Rouge River Center

February 12

Definition

―Self compacting concrete, Self placing concrete, or Self leveling concrete. These concretes are highly flowable concretes that can spread into place under their own weight and achieve good consolidation without internal or external vibration and without exhibiting defects due to segregation and bleeding.‖

- Kamal Khayat

History

• SCC was first developed in Japan in the

1980’s

• First SCC mixes were hybrids of

underwater concretes (tremie mixes).

• The Technology was transferred to Europe

in the 1990’s with the development of

polycarboxylate generation of

superplasticizers.

• SCC Technology transferred to North

America in the Late 1990’s via

primarily University Research.

• Producing a SCC mix in a Ready Mix

Plant is more challenging than

producing one in the Laboratory.

SCC Mix Design Process

• Cementitious materials require selection on

blaine and reactivity.

• Aggregates - Attention to Maximum size, particle

shape, gradations and sand / stone ratios

• Admixtures - Superplasticizers and viscosity

modifiers

• Proportioning - A SCC mixture is much more

scientific than that of conventional concrete

mixes.

• Conventional concretes start to

segregate at approximately 8 in. - 10

in. slump.

• A well designed SCC mix does not

segregate. It has high deformability

and excellent stability characteristics.

Cut Cylinders showing

segregation

Consolidation of

Conventional Concrete

Labor Intensive

Labor Dependent

Quality Control?

Safety Concerns

Consolidation of

Conventional Concrete

Applications of

Self-Consolidating Concrete

Cinque Terre

Vancouver, Canada

5 story luxury condominium project

The labor to place and finish each

suspended slabs was reduced over 90%

from 35-man-hours to 3-man-hours.

Traditional Chinese gate to welcome visitors

Chinatown Millenium Gate

Vancouver, BC

Douglas County Justice Center Expansion

Castle Rock, COApplication: Block fill

Block fill Flows Horizontally Without Vibration

SCC test at National Concrete Masonry Assn.

SCC placed from a crane bucket

through a 4‖ PVC pipe 10’ vertically

down over a parapet wall on the dam

face and 4’ horizontally into a form.

Robert Moses Dam

New York Power Authority

Auger-Cast Piles

Rockville, MD

Auger schematic

Consolidation in heavily reinforced sections 50MPa, Heat generation, Shrinkage. Required surface finish, Exposed outrigger columns

One Wall Center

Vancouver, BC

Contractor

Saw the mix flow into heavily reinforced sections without vibration with excellent surface finishes

Engineer

Observed the product’s moderate heat, early strength development, with favorable shrinkage and modulus of elasticity results.

Kidd Mine

Timmins, OntarioApplication: Mass concrete

• Conversion of abandoned shaft into main shaft

– Placement location 5000 ft underground

– Unstable ground with a large traversing fault

– Critical step on construction schedule

• Contractor: Cementation Skanska Canada Inc.

• Specified Performance

– 3500 psi in 28 Days

– Low Heat of Hydration – minimize temperature peak

– Fluid to self-leveling consistency – no ability to properly consolidate

• Placement Techniques

– Borehole from surface to 4800 level

– Pump 500 ft. to top of shaft

– Freefall maximum of 400 ft.

ELEV 1800

Step #1 - slash to 6m below 48

Pour sub collar & collar

104.7278

Void to be filled

Calgary, Alberta

Visual Barrier Walls

City of Arvada, Colorado

303 precast concrete panels

8.5’ x 18.5’ x 6‖ with formliner

― By eliminating the vibration step in the casting process, it was sort of like an insurance policy, reducing the risk of variation in the labor efforts.” Xernie Meritt, partner Concrete Express

― The fast rate of strength gain of the Agilia mix enabled us to pour the panels in the afternoon, and lift them the next morning. That was a big help to our schedule.” Joe O’Dea, partner Concrete Express

Why does it flow ?

Void Packing

20mm

10mm

5mmFines

Cement

paste

Particle Size - Void Packing.

20mm 14mm 10mm 5mm sand cement water

Workability

• Fluid material

•Input of energy

•Movement of particles

• Overcome internal friction

Ettringite

C3A

CH2 C

C O

O

CH3

CH2

CH2

O

O

CH2

CH2

CH3

CH2

CH2

C

CO

O

H3C

CH2

CH2

O

O

CH2

CH2

CH3

CH2

CO

O-

CH3

C

C

CH3

O-

OC

C

CH3

O

O

C

CH2

C

C

O

O

H3C

CH2

CH2

O

O

CH2

CH2

CH3

CH2

CH2

C

CH3

O

O

C

CCH

3O

O

C

CH2

C C

O

OH3C CH2CH2O OCH2CH

2CH3

CH2

H2C

C C

O

O

H3C

CH2

CH2

O

OCH2CH2

CH3H2C

CCH3

O

O

C

CH2

SO42

-

SO42-

SO42

-Ca2+

Ca2+

Ca2+

Ca2+

SO42

- SO42

-

Ca2+SO4

2

-

Ca2+

Cement-HRWR interaction.

Robustness is a key element180.8

182.3

183.7

185.1

186.5

187.9

189.3

190.8

192.2

193.6

195.0

196.4

197.8

199.2

200.7

202.1

203.5

204.9

206.3

207.7

209.2

0.441

0.470

0.499

0.527

0.556

0.585

0.614

0.643

0.672

0.701

0.730

0.759

0.788

0.817

0.846

0.875

0.904

0.933

0.961

1.019

eau (l/m3)

%G

L2

7/C

ime

nt

sec

75.0-80.0

70.0-75.0

65.0-70.0

60.0-65.0

55.0-60.0

50.0-55.0

45.0-50.0

Slum p Flow

1Rayon :

6 6 .1

5 8 .8

6 3 .9

4 9 .9

5 5 .8

7 4 .8

7 5 .8

0 .9 9 9R2 =

SP

do

sa

ge

Water (l/m3)

CLASS A w/ SUPER SELF CONSOLIDATINGSIX SACK 15 %ASH

MAT ERIAL UNIT S UNIT S

CEMENT 480 500

FLYASH 84 0

SLAG 0 350

SAND - 0 . 2 1289 # 1418

GRAVEL (GR A) 1850 0

GRAVEL (GR P) 0 425

LIMEST ONE 0 0

PEA GRAVEL (GR F) 0 900

WAT ER 30.0 250 # 295

SUPERP 1 28.2 1 55.3

AIR % 1.5 2

TOTAL VOLUME 27.00 27.00

7.35 CF 9.74 CF

Standard Class A Structural Mix vs Self Consolidating Mix

I-10 Twin-Span

Pile Void Fill

Rainbow Bridge

Rehabilitation Project-2005

Niagara Falls Bridge Commission

Rainbow Bridge

• Crane access only on north side of bridge

• Repair work was needed on the south side

• Contractor ran a 4‖ PVC pipe 30’ at a 30

degree angle

• SCC was bucketed down to the pipe

• SCC ran down the pipe into the form

MTO

Madawaska River Bridge

SCC—MTO

• SCC for soffit repairs

beneath the deck in

the archways on this

Bridge.

• The thickness of

patches was between

1.5 and 4 inches.

The contractor worked from a barge to form the

underside of the archways.

Formwork in place

SCC was poured into a trough that was drained by a 4 inch core hole in the deck. Most of the repair was under the paved portion of the bridge so the SCC had to travel approximately 15-20 ft, some of this distance through chipped out channels that had a cross sectional area of 2X4 inches.

The SCC completely filled the space and tensile-bond

tests failed in the underlying concrete beneath the SCC-

Concrete interface.

Slump Flow Test

• Concrete is poured into cone in one lift

• No rodding or vibration

• Slump Flow is the average of two

measured diameters

• Assesses the deformability capacity of the

concrete under a low shear rate regime

(self weight)

• Slump Flow:18 in.to 25 in.max.30 in.

Slump flow measurement

Concrete Properties:

• Creep and Modulus of Elasticity– Similar to standard concrete

• In air entrained concretes.. Air void systems equal to or better than conventional mixes

• Chloride permeability <1000 coulombs

• Shrinkage as per ASTM C 157 Values are similar to conventional concretes using the same materials

Concrete Properties

• Durability:

Freeze Thaw testing ASTM C 666

Dependent upon mix designs and materials used 95%- 100%

• Setting Time:

Typical setting times as determined by ASTM C 403 will be similar to conventional concretes

Structural Engineer

• Ability to design with

higher reinforcement

density

• Bond to reinforcing

steel

• Improved structural

Integrity

Architect

• Improved Aesthetics

• Design creativity

enhancement

• Consistency of Finish

appearance

• Sharp Lines

Reid Agilia Job - Showing Door

and Vent Openings