siegfried stiemer solomon tesfamariam marjan...

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PIsSiegfried StiemerSolomon Tesfamariam

HQPsJohannes Schneider (PhD candidate)

Matiyas Bezabeh (MASc student) Tobias Fast (MASc student)

Chris Piper (Undergraduate student)Carla Dickof (MASc, graduated, @Fast&Epps)

NEWBuildS CLT Industry Focus DayJuly 19, 2013, Vancouver, BC

Timber Steel Hybrid SystemsFPInnovationErol Karacabeyli Marjan Popovski

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Evolution of our Design

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A hybrid building or structure uses different construction materials (steel-wood, steel-concrete, concrete-wood, etc.)

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TIMBER STEEL

30-storey building proposal

Steel skeleton building structure

CLT-Steel hybrid system

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• Connections for CLT-steel frame hybrid buildings

• CLT infill in the steel moment resisting frames

• Displacement based design of CLT-infilled steel moment resisting frames

Active Research Topics in ourCLT-Steel Hybrid Systems Group

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Connections…

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Challenge in CLT-Steel connection

CONNECTIONS

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Connections for CLT Walls

• Bracket A (90 x 48 x 3.0 x 116)

• Fasteners

Bracket B (BMF 105)

a) Spiral Nail 3.8 x 89 mm

b) Ring Shank Nail 3.4 x 76 mm

c) Ring Shank Nail 3.8 x 60 mm

d) Self tapping Screw 5 x 90 mm

e) Self tapping Screw 4 x 70 mm

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Connection Test Set-up

Set-up Parallel to Grain Set-up Perpendicular to Grain

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Observed Failure Modes

Pull-out failure Net tension failureShear failure

Edge break out Group tear-outWood crushing

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Connection Ductility and Energy Dissipation

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(a) (b)

(a) (b)

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CLT infills…

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Hybrid Frame: Parametric Study

• Three steel frames, with three different ductility factors are designed, Limited ductility (LD) and Ductile (D).

• For each ductility level, three levels of CLT infll patterns are considered

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Cross Laminated Timber (CLT) as Infill

CLT Panel

Connections

Gap (δ)

Steel Frame

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Effect of Number of Storeys: Limited Ductility Steel Moment Frames for all Infill Configurations

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Evolution of our Design

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Design parameters…

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Earthquake Loads and Ductility Factor

Inertia forces caused by earthquake motion equivalent lateral forced (ELF), NBC 4.1.8.6:

V = S(Ta)MVIEW/(RdRo)

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Ductility and Overstrength: Six Storey Building

Plain 1 Bay 2 Bays 3 Bays

Duc

tile

Model µT 6.92 2.28 2.75 2.14

1.74 1.78 2.43 2.48

NBCC Rd 5.0 2.0

Ro 1.5 1.5

Lim

ited

Duc

tility

Model µT 2.91 2.12 2.46 2.33

1.70 1.85 2.14 2.19

NBCC Rd 2.0 2.0

Ro 1.7 1.5

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Displacement based design…

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(Priestly 2000)

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Hysteresis behavior of CLT infilled SMRF with different gap

-300 -200 -100 0 100 200 300-400

-300

-200

-100

0

100

200

300

400

Displacement (mm)

For

ce (

KN

)

10 mm gap CLT infilled frame

-300 -200 -100 0 100 200 300-400

-300

-200

-100

0

100

200

300

400

Displacement (mm)

For

ce (

KN

)

20 mm gap CLT infilled frame

-300 -200 -100 0 100 200 300-400

-300

-200

-100

0

100

200

300

400

Displacement (mm)

For

ce (

KN

)

40 mm gap CLT infilled frame

-300 -200 -100 0 100 200 300-400

-300

-200

-100

0

100

200

300

400

Displacement (mm)

For

ce (

KN

)

60 mm gap CLT infilled frame

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Area Based Approach for Equivalent Viscous Damping

Constants Values

a 6.1

b 0.00628

c 0

d 6.723

least square regression technique was used to develop the constants

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Evolution of our Design

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AcknowledgementsNatural Sciences and Engineering Research Council (NSERC)

Steel Structures Education Foundation (SSEF)

Thank you….