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ACI WEB SESSIONS

The Art of Designing Ductile Concrete in the Past 50 Years: The Impact of the PCA Book and Mete

A. Sozen, Part 1

ACI Fall 2012 ConventionOctober 21 – 24, Toronto, ON ACI

WEB SESSIONS

Michael E. Kreger is a Professor of Civil Engineering at Purdue University. He received BS, MS, and PhD degrees from the University of Illinois, and is a registered professional engineer in Texas. He joined the faculty at Purdue University in 2004 to serve as the first Director of the Bowen Laboratory for Large-Scale Civil Engineering Research after serving on the faculty

at The University of Texas at Austin for 20 years. He is a Fellow of the American Concrete Institute, serves on numerous ACI technical committees, including the ACI Building Code subcommittee for Safety, Serviceability and Analysis, and just completed six years of service on ACI's Technical Activities Committee. His research related to prestressedconcrete has twice received the T.Y. Lin Award from ASCE and has influenced changes in the ACI Building Code, AASHTO Design Specifications, and Indiana DOT and Texas DOT practice.

Selvarajah Ramesh, Michael Kreger,& Mark Bowman

Impact of the Blume, Newark, and Corning Text on the Development of a Composite Core-Wall System for Use in Earthquake-Resistant Tall Buildings

Composite Core-Wall System –The Devil’s in the Details

Acknowledgements

• Charles Pankow Foundation

• CANRON

• Magnusson Klemencic Associates

• Prof. Michael Engelhardt (UT-Austin)

Why a composite core-wall?

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Typical Core Wall Configuration

28’-6”

42’Project Phases

• Transverse ties between plates

• Plate-to-plate connection

• Stability of plate assemblies

• Foundation details

• Base connection

• Proof-of-concept wall test

• Development of design procedures

Stability ofPlate Assemblies

Foundation DetailsWelds between Rebar and Plate

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Connection at Base of Wall Plates Alternative Connection at Baseof Wall Plates

Weld Tests Wall Test- Elevation

27’

Wall Test- Plan

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Final Cast Testing

-500

-400

-300

-200

-100

0

100

200

300

-1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5

Lat

eral

Loa

d (k

ip)

Drift (%)

Lateral Load versus Drift

Cycle 1

Cycle 2

Cycle 3

Cycle 4

Cycle 5

Cycle 6

Cycle 7

Note: Load and drift away from the strong wall are positive

Load was applied at 295 in. height

C7

C4

C7

C6

C6

C5

C 4 & 5

C7C6

C7

C4

C 4 & 5

C 5 & 6

Drift (%)

Late

ral L

oad

(kip

s)

Plate buckling

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-450

-350

-250

-150

-50

50

150

250

-10,000 -5,000 0 5,000 10,000 15,000

Lat

eral

Loa

d ( k

ip)

Strain (in/in*10^6)

Lateral Load versus Strain - at south end (web)

Cycle 1

Cycle 2

Cycle 3

Cycle 4

Cycle 5

Cycle 6

єy = 2300 μє

C4

C6

C5

C4

C6

C6C5

C4 & C5

C3

C2

C4

C3

C2 & C3

Note: Load away from the strongwall (towards north) is positive

Late

ral L

oad

(kip

s)

Strain (in/in * 106)

-450

-350

-250

-150

-50

50

150

250

-10,000 -5,000 0 5,000 10,000 15,000

Lat

eral

Loa

d ( k

ip)

Strain (in/in)

Lateral Load versus Strain - at north end (flange)

Cycle 1

Cycle 2

Cycle 3

Cycle 4

Cycle 5

Cycle 6

Cycle 7

C7

C6 & C7

C4

C5

C6

C7

C6

C6

C4

C4 ,C5& C6

C7C6

C5

єy = 2300 μє

Note: Load away from the strongwall (towards north) is positive

C3

C2

Strain (in/in * 106)

Late

ral L

oad

(kip

s)

-8,000

-6,000

-4,000

-2,000

0

2,000

4,000

6,000

0 10 20 30 40 50 60 70 80Str

ain

(μє)

Distance from south end (in)

Strain versus Distance from South End - Along the depth of the wall

Drift = - 0.75%, Load = - 415.2 kip

Drift = - 0.97%, Load = - 442.2 kip

Drift = - 1.0 %, Load = - 397.3 kip

єy = 2300 μє Strains on flanges

Note: Strain readings when the specimen was pushed towards strong wall

Strain measurements at 1- inch from bottom

Load was applied at 295-in. height

Str

ain

(in/in

* 1

06)

Distance from South End (in)

Concluding Remarks

• Details

• Flanges at Wall Ends

• Developing Design Procedures