presentacion robert tremblay marzo 2014

1Robert Tremblaycole Polytechnique de Montral

Colegio de IngenierosSantiago, ChileMarch 18, 2014

Seismic Design of Steel Structures: North American Practice &

Challenges for Industrial Buildings

R. Tremblay, Polytechnique Montreal, Canada 2

2R. Tremblay, Polytechnique Montreal, Canada 3

RASCE/SEI 7-10

3-1/468

3-1/24-1/2

87


4 Ductile seismic design

Braced frame systems

Concentrically braced frames

Eccentrically braced frames 341-10

Buckling restrained braced frames

Moment frames and plate wall systems

Heavy industrial buildings: challenges

Plan


Ductile Seismic Design

h

h

W

T = 0.38 s5% damping

Elastic

0.0 10.0 20.0 30.0 40.0Time (s)

-0.5

0.0

0.5

ag (g)

-1.0

0.0

1.0

/ h (%)

Horizontal 90 deg.

0.0126 h-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

V / W

1.28 W

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

/ h (%)

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

V / W


5Take advantage of thehigh ductility of steel

FF

Fracture,instability,etc.

Ductileresponse

y

u


0.0 10.0 20.0 30.0 40.0Time (s)

-0.5

0.0

0.5

ag (g)

-1.0

0.0

1.0

/ h (%)

Horizontal 90 deg.

0.0126 h-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

V / W

1.28 W

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

/ h (%)

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

V / W

-1.0

0.0

1.0

/ h (%)

-0.017 h

-1.0

-0.5

0.0

0.5

1.0

V / W

0.33 W

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

/ h (%)

-1.0

-0.5

0.0

0.5

1.0

V /

W

h

h

h

W


Vy = 0.25 W

Elastic


6-0.06 -0.04 -0.02 0.00 0.02 0.04 0.06Plastic Rotation (rad.)

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

M /

Mpr

M. Englehardt Ecole Polytechnique of Montreal, 1996

Ecole Polytechnique of Montreal, 1996


-8 -4 0 4 8

/ y-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P / Py

HSS 102x76x6.4 - KL/r = 112

Tensionyielding (typ.)

Inelastic bucklingwith plastic hinge (typ.)

PPPlastic

Hinge

+

-

+


7h

h

W


Vy = 0.25 W

0.0 10.0 20.0 30.0 40.0Time (s)

-0.5

0.0

0.5

ag (g)

-1.0

0.0

1.0

/ h (%)

Horizontal 90 deg.

0.018 h-0.4

-0.2

0.0

0.2

0.4

V / W

-0.36 W -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0/ h (%)

-0.4

-0.2

0.0

0.2

0.4

V / W

-1.0

0.0

1.0

/ h (%)

-0.017 h

-0.4

-0.2

0.0

0.2

0.4

V / W

0.33 W

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

/ h (%)

-0.4

-0.2

0.0

0.2

0.4

V / W

h

Vy = 0.25 W


Effects of Magnitude and Distance

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.5

1.0

1.5

2.0

2.5

S a (g

) M 7.0-7.510-20 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.5

1.0

1.5

Sa

(g)

M 7.0-7.530-50 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.4

0.8

1.2

1.6

2.0

Sa

(g) M 6.5-7.0

10-20 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.5

1.0

S a (g

)

M 6.5-7.030-50 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.5

1.0

S a (g

)

M 6.5-7.070-100 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.5

1.0

S a (g

) M 6.0-6.530-50 km

Earthquakes in California Site Class B 5% damping


80.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.4

0.8

1.2

1.6

2.0

S a (g

)

Los Angeles AreaSite Class B

M6.0 - M7.5Dist. = 10-100 km

0.0 0.5 1.0 1.5 2.0 2.5 3.0Period, T (s)

0.0

0.4

0.8

1.2

1.6

S a (g

), C

s

Los Angeles AreaSite Class B

Sa (Elastic)Cs (OCBF - R = 6.0)

x 1/R

Design Spectra

& Design for Inelastic Response




VeR

V =

Perimetermembers

RoofDiaphragm

Braceconnections

Bracingmembers

Anchor rods

Foundations

V V

Capacity Design ProcedurePoutrelle(typ.) Poutre de toit

(typ.)

Poteau(typ.)

Feuille de tablier mtall ique

typ.)

Contreventement (typ.)


10

Grav.

Grav.

C

C' T

u

u y

Grav.

E

> E

> E

Grav.

Grav.

Grav.

Column designed for gravity plus expected brace tensilestrength

Gusset plates designed incompression for the expectedbrace compressive strength

2. Design other elements :

1. Select Braces:

Design for gravity + ECheck KL/r, b/t, etc. for ductile response

Gusset plate designed in tensionfor the expected brace tensilestrength

Two-Step Capacity Design Procedure:


Plastic Hinge (typ.)

Shearyielding


Tensionyielding

Plastic HingeTension

yielding

Tensionyielding

Compressionyielding e


Plastic Hinge

End-plateBending

Shearyielding

Ductile Seismic Force Resisting Systems


11

AISC 360-10

ASCE 7-10AISC 341-10


NBCC 2010

CSA S16-09


12

Building code main objective is to protect life and prevent structural collapse under ground motions

In view of high level of ground motion considered (2% in 50 years) and the difficulty in predicting ground motions and their effects on structures

ductile seismic design represents an effective strategy to achieve code objectives by controlling the system response and force demand.


Control ofLocal Buckling


13

Expected (probable)material strength

Liu, J. et al. (2007). AISC Eng.


Concentrically Braced Frames (SCBFs)

Energy dissipated in bracing members through tensile yielding and flexural hinging

Connections and other members expected to remain essentially elastic

Tensionyielding (typ.)

Inelastic bucklingwith plastic hinge (typ.)


14



15



16

Rehabilitation


Kobe 1995


17


Northridge 1994Photos from Peter Maranian, Brandow and Associates (P. Uriz Thesis, 2005)


18

Uriz and Mahin (2004) Univ. of California, Berkeley

Fracture in1st cycle at1 2% hs1

2


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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P /

AgF

y

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

HSS 254 x 254 x 12b/t = 18, KL/r = 42


19



20


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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P /

Py

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

RHS-4KL/r = 40b0/t = 17

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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

RHS-2KL/r = 40b0/t = 13

RHS-19KL/r = 60b0/t = 13

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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P /

Py

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

CHS-1KL/r = 42b0/t = 30

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

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs (%)

-3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0

/ LH (%)-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

-4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 / hs (%)

CHS-2KL/r = 62b0/t = 31

W-6KL/r = 67b0/t = 5.9


21

0.0 0.5 1.0 1.5 2.0 2.5

Brace Slenderness, = (Fy / Fe)0.50

5

10

15

20

25

Duc

tility

at F

ract

ure,

ff = 2.4 + 8.3

y

-6 -4 -2 0 2 4 6

-10 -8 -6 -4 -2 0 2 4 6 8 10

.

KL/r = 93HSS 127x76x4.8

KL/r = 142HSS 76x76x4.8

f f

yy

-6 -4 -2 0 2 4 6

-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P /

A gF y

KL/r = 42HSS 254x254x12

f



22


W4

W6

W4 W660004000

2000

0

2000

4000

6000

3 2 1 0 1 2 3

Interstorey Drift Angle (%)

P(k

N)


23

Design Bracing Configuration Along any braced line, between 30% & 70% of lateral

load is resisted by tension braces Tension-only braced frames not permitted K-bracing not permitted


R. Tremblay, cole Polytechnique of Montreal & D. Mitchell, McGill University 46

24

Design Bracing Members Braces must resist gravity + lateral loads Pn in tension and compression as per AISC 360-10 KL/r < 200 Section must meet seismic hd limits For built-up sections, individual components must

meet KL/r limits and stitch subjected to shear under buckling must meet minimum shear strength


L

L

H

N

KLout 0.9 LHKLin 0.5 LN

KLout 0.5 LHKLin 0.5 LN


25


Bracing ConfigurationTension-only braced frames permitted

Bracing MembersSection must meets b/t limits that vary with KL/r

Cexp

Cexp


Design Expected Brace Strengths

P/P

y

Texp

26


0.0 0.5 1.0 1.5 2.0 2.5

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Cu

/ AgF

y

Cu (S16-01, n = 1.34)Cu (AISC 1999)

0 50 100 150 200KL/r

0.0 0.5 1.0 1.5 2.0 2.50.0

0.2

0.4

0.6

0.8

1.0

C' u

/ A

gFy

(Duc

tility

= 1

.0)

Cu (S16-01, n = 1.34)

0 50 100 150 200KL/r

0.0 0.5 1.0 1.5 2.0 2.50.0

0.2

0.4

0.6

0.8

1.0

C' u

/ A

gFy

(Duc

tily

= 3.

0)

Cu (S16-01, n = 1.34)C'u (mean)

0.0 0.5 1.0 1.5 2.0 2.50.0

0.2

0.4

0.6

0.8

1.0

C' u

/ A

gFy

(Duc

tility

= 5

.0)

Cu (S16-01, n = 1.34)C'u (mean)


Texp = A RyFy

Cexp = A (1.12 Fcr) where Fcre = Fcr with RyFy< A RyFy

Cexp = 0.3 Cexp

Cexp

Cexp

Texp

27

Texp = A RyFyCexp = A (1.12 Fcr) ,Fcre = Fcr with RyFy

< A RyFyCexp = 0.3 Cexp


Schimdt and Bratlett (2002)


28


Design Brace ConnectionMust resist brace Texp & 1.1 Cexp

Must allow for ductile rotational behavior or resist 1.1 x brace expected flexural strength


29

Kobe 1995

Archambault et al. (1995)Tremblay and Bolduc (2002)

cole Polytechnique,Montreal


Yang and Mahin (2004) Univ. of California, Berkeley


30



31


Kobe1995


32

Sabelli (2003) Sabelli (2005)

Sabelli (2003)


Prototype Test Specimen

Attachment toload frame:

LW

LW

LC-C

LTS

2 t 2 t g g

Gussetplate

Gussetplate

35O

Coverplate

Coverplate

5182

(min

) @

793

7 (m

ax)

102

290

35O

Elevation

Specimen

End Restraint

Side View

EndHinge


33



Design Columns and BeamsMust resist gravity loads plus two brace force scenarios:

Upon first buckling & yielding (Texp & Cexp) In post-buckling range (Texp & Cexp)

Beams in V and inverted-V bracing must be continuous between columns

Column sections must meet hdBeam sections must meet md

34


At Buckling Post-Buckling

T T

T T

T T CC

CC

CCexp,1 exp,1

exp,2 exp,2

exp,3 exp,3 exp,3exp,3

exp,2exp,2

exp,1exp,1

F3 F3F3

F2 F2F2

F1 F1F1

W W WW W WW W W

Brace force scenarios for columns:

Northridge 1994Photos from Finley 1999(P. Uriz Thesis, 2005)


35

Taiwan 1999



36



F F

F F

F FL,x L,x

L,x L,x

R,x R,x

FR,x FR,x

C C

C C

C C

C C

T T

T T

T T

T T

exp,x+1 exp,x+1

exp,x+1 exp,x+1

exp,x exp,x

exp,x exp,x

exp,x+1 exp,x+1

exp,x+1 exp,x+1

exp,x exp,x

exp,x exp,x

1.2 w + 1.0 w 1.2 w + 1.0 w

1.2 w + 1.0 w 1.2 w + 1.0 w

D D

D D

L L

L L

Brace force scenarios for beams:

Note: Redundancy factor, ,and seismic load effectswith overstrength factor, 0,as specified in ASCE 7-10are not considered.


SCBF

5500

EBF BRBF

2 @ 4000= 8000

[mm]ELEVATIONSM

RF (t

yp.)

BF (typ.)

5 @ 9000 = 45 000

[mm]PLAN

300(slab edge)

5 @

900

0 =

45 0

00

Gravity loads: Roof: Dead = 3.2 kPa Live = 1.0 kPa Floor: Dead = 3.5 kPa Partitions = 1.0 kPa Live = 3.8 kPa Exterior walls = 1.5 kPa

Seismic Load Data (NCh433): Zone 2 Soil Type C A= 0.30 g In-plane torsion omitted

Load Combinations: 1.2D + 1.6L 1.2D + 1.0L + 1.4E 0.9D + 1.4E

Seismic weight: P = 7720 kN (Level 9) 12635 kN (Levels 2-8) 12840 kN (Level 1)

Steel: BRB cores: Fyc = 260-290 MPa Other members: Fy = 345 MPa

37



Static method of analysis

38


Brace Design


At Buckling

Column Design

1103

4890

4092 47492492

7916 791625914437

+ 1.2 x 644 (D)+ 1.0 x 372 (L)= 5893

-0.9 x 644 (D)= 1913

1103

4092

2001 4890

29072907

70077007

599

169 169169

599599 599

1692001

39


Post-Buckling

Column Design

1103

4890

1227 5136662

6085 60867774437

+ 1.2 x 644 (D)+ 1.0 x 372 (L)= 6280

-0.9 x 644 (D)= 82

331

1227

600 4890

29072907

70077007

856

812 812812

856856 856

812600



Beam Design

1103 331

4092 1227

2001 600

2001 600

1103 331

1498 1210

939 556

1498 1210

939 556

1077 842

2907 2907

7007 7007

4890 4890

4890 4890

2907 2907

-1498 -1210

-939 -556

-2800 -2565

M = 243 M = 243

M = 759 M = 3896

M = 2785 M = 3939

1498 1210

939 556

1077 842

1.2 w + 1.0 w = 8.71

1.2 w + 1.0 w = 24.0

1.2 w + 1.0 w = 24.0

1.2 w + 1.0 w = 8.71

1.2 w + 1.0 w = 24.0

1.2 w + 1.0 w = 24.0

D

D

D

u u

u u

u u

D

D

D

L

L

L

L

L

L

[kN,m]

40

Consider more realistic brace KL

9000

O41.6 W610 Beam

Bolted EndPlate Connection

750 +

/-

4500 +

/-602

1

Hinge

4000


Brace sizes are reduced, increasing T*, reducing seismic loads

T* = 0.55 s -> 0.65 sC = 0.119 -> 0.093 (22% decrease in seismic loads)


41


SCBF

5500

2 @ 4000= 8000

Eccentrically Braced Frames


Energy is dissipated through shear or flexurein link beams

Connections and other members (including beams outside links) expected to remain essentially elastic


Shearyielding

e

42


Filiatrault et al.

Residential buildingsMontrealMartoni Cyr


43

Hockey Canadian, MontrealR. Tremblay, Polytechnique Montreal, Canada 85

Wellington, New-Zealand 2013


44

Built-up rectangular tubular link beams

Contreventement non requispour le segment ductile !

Berman, J.W, and Bruneau, M. 2008. Tubular Links for Eccentrically Braced Frames I: Finite Element Parametric Study. ASCE J. Struct. Eng., Vol. 134, No. 5, pp. 692-701.


Takanashi &Roeder1976 Roeder

1977

Kasai1986

Malley1983

Engelhardt1989

Ricles1987

System originally developed by Prof. Povov with

+ othersR. Tremblay, Polytechnique Montreal, Canada 88

45

Design Bracing Configuration


Symmetrical Pf 0 in ductile links Pinned beam-to-column joints

Shorter beam spans Good clearance

Rigidconnection(typ.)

Pinned connection(typ.)

e

e

= L/ep

= L/ep

p

p

L

L

L

e

L

M

MVV

V

V = 2 M / e

M


Design Link BeamsResistance can be governed by shear (short links) or flexure (long links). Resistances affected by axial load:

Section must meet hd (md for flanges if e < 1.6 Mp/Vp )e > d; upper limit on e applies in presence of axial load

Must meet limits on plastic rotation (p): from 0.02 rad for e < 1.6 Mp/Vp to 0.08 rad for e > 2.6 Mp/Vp

Need for end and intermediate stiffeners; depend on yielding mechanism & p

46


For center links (M = 0 at e/2):

e/2 e/2

M

M

V

V

M

L

L

L

L

L

For shear yielding: Vn = VpFor flexural yielding: Vn = 2 Mp/e

e

Shorter links generally preferred: Higher lateral frame stiffness Higher energy dissipation capacity Less stringent (md for flanges) Easier to design beams outside links

hp

s

= L/ep p php

s

= L/ep

p p


47


Design Adjusted link shear strength

Vadj = 1.25 RyVn (I-shaped links)= 1.40 RyVn (built-up tubular links)

May be multiplied by 0.88 for beams outside links and for columns in structures more than 3 storeys


Design Columns and Beams

Must resist gravity loads plus Vadj

Column sections must meet hd. Beam outside links and braces must meet md section requirements

e/2e/2 L/2- /2e

adj

adj

adj

adj

adj

beam

beam

beam

brace

col

L/2

V

V

V

V

V

P

V

M

P

P

48



Must resist gravity loads plus Vadj

Column sections must meet hd. Beam outside links and braces must meet md section requirements

e/2e/2 L/2- /2e

adj

adj

adj

adj

adj

beam

beam

beam

brace

col

L/2

V

V

V

V

V

P

V

M

P

P

SCBF

5500

EBF BRBF

8 @

400

0 =

32 0

00

[mm]ELEVATIONS

MRF

(typ

.)

BF (typ.)

5 @ 9000 = 45 000

[mm]PLAN

300(slab edge)

5 @

900

0 =

45 0

00

Gravity loads: Roof: Dead = 3.2 kPa Live = 1.0 kPa Floor: Dead = 3.5 kPa Partitions = 1.0 kPa Live = 3.8 kPa Exterior walls = 1.5 kPa

Seismic Load Data (NCh433): Zone 2 Soil Type C A= 0.30 g In-plane torsion omitted

Load Combinations: 1.2D + 1.6L 1.2D + 1.0L + 1.4E 0.9D + 1.4E

Seismic weight: P = 7720 kN (Level 9) 12635 kN (Levels 2-8) 12840 kN (Level 1)

Steel: BRB cores: Fyc = 260-290 MPa Other members: Fy = 345 MPa


49

EBFs Modular Linkswith N. Mansour & C. Christopoulos, Univ. of Toronto



50



51


102

52

Repair using Self-compacting concrete(Sikacrete-08 SCC)Repair of main transverse surface

cracks using Low-viscosity injection resin (Sikadur 52)



53

Comparisons for cycles at 0.08 rad.:

( reinforcement plates)(3/16 reinforcement plates)



54

Buckling Restrained Braced Frames

Energy dissipated in bracing members through tensile and compression axial yielding


P

P

PP

P

Cross-Section

SteelCore

MortarFill

SteelTube

UnbondingMaterial


Wakabayashi et al. (1973)

Watanabe et al. (1988)


55

cole Polytechnique 1998 Qubec City (1999)

Buckling Restrained Braced Frames

-4.0 -2.0 0.0 2.0 4.0-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

V / V

/

y

y



56

Qubec City (1999)

Vancouver (RJC)

Montreal (Canam)


0 5 10 15 20 25Time (s)

-0.20.00.2

Acc

el. (

g)

-0.8-0.40.00.40.8

Roo

f / h

n

-0.8-0.40.00.40.8

Roo

f / h

n

-0.8-0.40.00.40.8

Roo

f / h

n

-20000

-10000

0

10000

20000

V B

ase

(kN

)

-20000

-10000

0

10000

20000

V B

ase

(kN

)

-1.0 0.0 1.01/ hs (%)

-20000

-10000

0

10000

20000

V B

ase

(kN

)

BRB-L

CBF

BRB-L

CBF

.

BRB-S

BRB-S


57

PP

L

EI , d

a Core

Concrete Fill r r

0

PP Gap

PP

Global buckling:

Local (core) buckling:


-10 -8 -6 -4 -2 0 2 4 6 8 10y

-2.0

-1.0

0.0

1.0

2.0

V/V y

All-steel BRBs


58


Eryasar & Topkaya 2010Usami et al. 2008


59



60



61

http://www.corebrace.com/

http://www.starseismic.net/

http://www.unbondedbrace.com/

Specialized suppliers (U.S.)


No special requirements (BRB have nearly symmetrical response)May be controlled by drift limit or available BRB capacities

Design Bracing Configuration


62

Select Ac:BRB assumed not resist gravity loads

=> required axial strength from lateral loads only Pn = AcFyc (compression & tension) with = 0.9 Notes: use lower bound for Fyc

round-off AcVerify availability of BRB and test data Determine stiffness factor KF for analysis

= KBrace / (EAc/Lc/c)

Design BRB members


9000

O41.64500

+/-60

21

L

L

c/c

c

4000


63

Two cyclic tests: individual BRB + sub-assemblageSpecimen Pysc within 50-120% of prototypeSpecimen design, fabrication and quality control as for prototypeTest displacements based on design storey drift bm

Tests used to demonstrate performance of the member and connections and to provide design data

Qualification tests of BRBs:


Adjusted (max) brace strengths from tests:Tadj = AcFycCadj = AcFyc

with and from C and T at the maximum testdeformations

Note: use upper bound for Fyc

Design BRB adjusted axial strength

-8.0 -4.0 0.0 4.0 8.0 y

-2.0

-1.0

0.0

1.0

2.0

P/P

y

Tmax

Cmax


64

Must resist gravity loads plus forces induced when the braces reach their adjusted strengths

Section must meet hd (md for flanges if e < 1.6 Mp/Vp )



C

C

C

C

T C

adj

adj

adj

adj

adj adj

Beam Design

Column Design

ChevronBRB

F

FC

C

T

T

F

F

L,x

L,x

R,x

R,x

C

C

C

C

T

T

T

T

and

adjx+1

adjx+1

adj,x

adj,x

adj,x

adj,x

u

u

u

u

adj,x

adj,x

0.9 w

1.2 w + 1.6 w

D

D L


65

At design stage, verify: Range of Fyc Strength factors & Stiffness factors KF Py range for which test data is available

On drawings, specify: Minimum Py (or Ac & Fyc), with tolerances Factors , and KF Reqd test brace axial deformations

Communication with BRB suppliers


Fyc = 260-290 MPaKF = 1.5

R = 6.0 (as EBF)T = 0.99 sQ0 = 871 kN / Frame

BRBF


66

BRBFSCBF


Moment Resisting FramesEnergy dissipated by plastic hinging in beams and limited shear yielding in column panel zones. Plastic hinging in columns permitted at the base and in single-storey structures.



67

Section must meet hdMust resist expected shear demand upon hingingMust be laterally braced

Design Beams

L'

L

L' = L - 2 x - d c

wpb

1.1 R My pb

1.1 R My pb

V = wL' / 2 + 2.2 R M / L'h y pb

Vh Vh


Section must meet hdMust satisfy weak beam-strong column criteriaexcept for:

Columns with Puc < 0.3 AcFy in single-storey buildings or at the top storey of multi-storey buildings;Columns with Puc < 0.3 AcFy when their total shear contribution < 20% of total storey shear resistance and 33% of storey shear resistance along their MF line; orColumns that have shear capacity to demand ratio 50% gretaer than in the storey above.

Design Columns


68

L'

L

L' = L - 2 x - d c x + d /2c x + d /2c

ww w

1.1 R My pb

1.1 R My pb

1.1 R My pb

1.1 R My pb

V = wL' / 2 + 2.2 R M / L'h y pb

Vh Vh

Vh

Vh

M'rc, i+1

M'rc, iCf, i

Cf, i+1

Weak beam-strong column criteria:

M*: projected at membercenter lines


x + d /2c x + d /2c

1.1 R My pb

1.1 R My pb Vh

Vh

V

V

Must meet: t > (dz + wz)/90Shear strength, Rn:

Design Column panel zone


69

L/2

V

L/2

h /2s

h /2s

Design Beam-to-column connections

Must accommodate 4% storey drift angleMeasured flexural resistance at column face at 4% storey drift angle > 80% MpbPerformance considered as demonstrated if pre-qualified connections are used; otherwise must be demonstrated through physical cyclic testing


http://www.aisc.org

Design requirements

Welding requirements

Bolting requirements

Requirements for 6pre-qualified connections


70

Welded Unreinforced FlangeWelded Web

Bolted End Plate

Kaiser Bolted Bracket

Bolted Flange PlateReduced Beam Section

Conxtech Conxl



71

MRF

Example



72

At Level 1:

M*pb = 656 + 738 = 1394 kN-m



73


Steel Plate Shear Walls

Energy dissipated through web plate (infill panel) yielding and plastic hinging in beams and at the base of columns



74

ING St-HyacintheQuirion Metal


Louis Crpeault Groupe Technika R. Tremblay, Polytechnique Montreal, Canada 148

75

University of Alberta (1997)


Work by Bruneau, Tsai et al.

-5000

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

5000

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3

Interstory Drift (%)

Bas

e Sh

ear F

orce

(kN

)

-5000

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

5000

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3

Interstory Drift (%)

2F S

hear

For

ce (k

N)


76

MF + web plate

V

+ ==

mf

wV

V

Distribution of Vx from analysis

Infill panel designed for 100% VxBeams Mpb such that VMF = 2 Mpb/hs > 0.25 Vx


Design of web plate


77

M' M'

M'

V

VV

C CF

C

q

h

h

i

i+1 i

w,i yi2 2

i+1

i

i+1

ipb,i pb,i

pb,ib,i b,i

r,i

br,i

br,i

c

c

b,i

bl,i

b,i

L - 2 x - d

x + d /2

C (T h sin ) (T h sin ) ] = [ + / 2 T = t F

(T sin )(T cos )

(T cos ) (T sin )

i+1i+1

i i

L

Design of beams (HBE)and columns (VBE)


Beam-to-Column Connections

M'

M'

Beam

V

V

PP

q

i

i+1

i

pbr,i

pbl,ibr,i

br,i

c

bl,i

bl,i

L - 2 x - d

i+1

i

Columns:Class 1, W Shapes

Beams:Class 1 or 2

CP groove weldsBacking bar removedRun-off tabs removedReinforcing fillet weldsTr = 60% Tr in Cl. 21.3

Type LD MRF


78

Corner cut-outs

Vian, D. and Bruneau, M. 2004. Testing of Special LYS Steel Plate Shear walls. Proc. 13th WCEE,

Vancouver, BC. Paper No. 978.

Purba, R. and Bruneau, M. 2007. Design Recommendations for Perforated Steel Plate Shear Walls. Report MCEER-07-0011, SUNY Buffalo, NY.


Berman, J.W. and Bruneau, M. 2005. Experimental Investigation of Light-Gauge Steel Plate ShearWalls. ASCE J. of Struct. Eng., 131, 2, 259-267.

Optimization of infill plates

Use of thin infill plates

0.9 mm thick ASTM A1008 (cold-rolled, carbon, commercial steel sheet)


79

Perforated infill plates

Vian, D. and Bruneau, M. 2004. Testing of Special LYS Steel Plate Shear walls. Proc. 13th WCEE,

Vancouver, BC. Paper No. 978.

Purba, R. and Bruneau, M. 2007. Design Recommendations for Perforated Steel Plate Shear Walls. Report MCEER-07-0011, SUNY Buffalo, NY.


Perforation(typ.)

V

D

* D * D + 0.7 S< 0.6

diag

diag

*

V> 4 rows

iL

> 4 rows

4545oo

diag

diag

S

S


80



81


Warning!

Only basic design requirements have been discussed; several other requirements must be applied including those related to loads and load combinations, demand critical welds, protected zones, bracing, quality control, etc.

Only the systems designed and detailed for high ductility have been introduced; provisions also exist for other systems exhibiting moderate and limited ductility that may be more appropriate for some applications.

R. Tremblay, Polytechnique Montreal 162

82

Bruneau, M., Sabelli, R., and Uang C.-M. (2003) Ductile Design of Steel Structures, 2nded., Wiley

AISC. (2013) Seismic Design Manual, 2nd ed., AISC

Filiatrault, A., Tremblay, R., Christopoulos, C., Foltz, B., and Pettinga, D. (2013)Elements of Earthquake Engineering and Structural Dynamics, 3rd ed.,Presses Internationales Polytechnique (PIP)

R. Tremblay, Polytechnique Montreal 163


83


Seismic Design of Heavy Industrial Buildings : Challenges


84

Structures are not buildings: Irregular structures with heavy point masses and loads

and low damping Design is process driven and structure will likely be

modified to accommodate changes to the process Equipment may interact with the structure

Structures may have limited redundancy Damage under severe earthquakes must be limited:

Structures may contain hazardous material No or short downtimes

Application of ductile seismic systems not practical, often impossible

Current building code provisions not suitable

Observations / Issues:


1. Simple code provisions to control inelastic demand: low R factors , use of dynamic analysis, etc.

2. Use of ductile anchorage systems with minimum stretch lengths in combination with shear keys

3. Use ductile fuses in key structural elements to control the force demand

4. Where applicable, use sliding or rocking systems to control input

Possible avenues:

Above avenues are listed in order of ease of implementation implementation and flexibility for future process changes;

however, the latest ones could be more effective

Ductility (or alternative similar approach) needed to accommodate uncertainty in ground motions and seismic response


85

In Canada, industrial structures are buildings and National Building Code (NBCC) applies.

New Annex proposed for inclusion in CSA S16-14 and which would be referenced in NBCC 2015:


1. Demand prediction from RS analysis2. Use/design of ductile anchorage3. Ductile structural fuses4. Multi-tiered braced frames

Recent related research work:


86

Demand Prediction from RS Analysis


Plan dimensions: 36 m x 60 m x 40 m Heavy equipment, including 1200t & 750t tanks Irregularities in mass and stiffness Montreal Site Class C Static, Response Spectrum & Linear response history

analyses


87

Structure has a large number of contributing modes


0

20

40

60

80

100

120

140

Dis

plac

emen

t (m

m)

Level

STAT-CNBCSTAT-ASCESPECTRALETH-MDIANETH-84e CEN


88

Use & Design of Ductile Anchors

22 4

00

16 8

00

5600

25 000 1675 1675

2 x 40t cranes

3 sites: Montreal, Vancouver & SeattleSeismic force demand from linear response history analysisDuctile anchors at column bases


-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

-0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2

Strength ( = 1)Strength ( = -1)

Stability ( = 1)Stability ( = -1)

P/RyPy

M/RyMp


89

Elastic time history analysis

0.71

%

0.70

%

0.67

%

0.87

%

0.67

%

0.66

%

0.63

%

0.81

%

0.0%

0.2%

0.4%

0.6%

0.8%

1.0%

STAT SPEC TH-MedTH-84th

c/h

, r/h

(%)

Analysis method

Crane levelRoof level

0.44

0.37

0.51

0.42

0.42

0.52

0.0

0.2

0.4

0.6

STAT SPEC TH-Med TH-84th

Acc

eler

atio

n (g)

Analysis method


n.a. 120%

121%

115%

149%

107%

106%

102%

120%

0%

50%

100%

150%


Stre

ss R

atio

(%)

Analysis method

Ext. base col.Top column

Seattle (Site Class D)

0.46

0.44

0.57

0.53

0.52

0.72

0.0

0.2

0.4

0.6

0.8


Acc

eler

atio

n (g)

Analysis method

)Crane levelRoof level

n.a.1.0

0%

0.88

%

0.78

%

1.01

%

0.91

%

0.79

%

0.70

%

0.93

%

0.0%

0.2%

0.4%

0.6%

0.8%

1.0%

1.2%

STAT SPEC TH-MedTH-84th

c/h

, r/h

(%)

Analysis method

)Crane levelRoof level

Vancouver (Site Class C)

160%

142%

115%

156%

94%

86%

76%

93%

0%

50%

100%

150%

200%


Stre

ss R

atio

(%)

Analysis method

)Ext. base col.Top column


Ductile anchorage at column bases

total =e +ie =total/Ri =total/(1 R)

e i

total =e +ie =total/Ri =total/(1 R)i = xH/h =i xh/HL=/ =/0.03

H

h

e i

,

verticalfuse

sh y fuse

FAR F


90

Anchor rodSpring for stability of analysis

1

2 3

4

5

6

7 8

Inelastic time history analysis



91

1.40

%

1.56

%

1.14

%

1.77

%

1.24

%

1.38

%

1.14

%

1.77

%

0.0%

0.5%

1.0%

1.5%

2.0%

TH-MD TH-84e CEN TH-MD TH-84e CEN

c/h

, r/h

(%)


With anchor yielding

Without anchor yielding


NCh2369 (2003)

Is 8db or 250 mm suitable for all applications?


92


Other buildings to be examined

HeadFrame (Mining)

Chemical Industry


93

Conveyor Towers

Pipe Racks


Tank Supporting Structures


94

DuctileStructuralFuses


-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / h (%)

-0.5

0.0

0.5

1.0

1.5

V /

Vy

Brace Fuse Test 3CTWithout FuseWith Fuse

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / h (%)

-0.5

0.0

0.5

1.0

1.5

V /

Vy


HS 102x102x4.8

280

200

200

40(typ.)

25.4 bolts@ 80x80 (typ.)

133

133271

64 hole(4 sides)

64 x 335 slotted hole(4 sides)

PL 6x63x250(2 sides)1

4

3


95

Fuses forHSS braces

P

P

P

P

C

C

C

C

T

T

T

T

C

C

C

C

T

T

T

T

T

L

L

L

T

C

F

F

c

C

u

uF

u

u

u

uF

uF

u

f

f

f

f

f

f

f

f

Section A

A

Steel Core

Mortar Fill

Steel Tube

T

C

C/TC/T


0 5 10 15 20Time (s)

-1.0

0.0

1.0

/ h

n (%

)

Without Brace FusesWith Brace Fuses

-0.2

0

0.2

a g (g

)

M7.0 1989 Loma PrietaStandford Univ. 360o

-2.0 -1.0 0.0 1.0 2.0

/ y-1.0

-0.5

0.0

0.5

1.0

P /

T u

-1.0 -0.5 0.0 0.5 1.0

B / hn (%)-0.5

0.0

0.5

V /

W

Without Brace FusesWith Brace Fuses

V NBCC

V NBCC


96

L

bAngle with

reduced section

Cut inHSS

HSS brace

Bucklingrestraining box L Lf

f

t w

Typ.A


1000 kNDynamicactuator

3.75

m

Loadingarm

W36

0x34

7 (ty

p.)

W310x179 (typ.)

Horizontalreaction block

6.0 m

Bracestudied

Bracefuse

Frame support(typ.)

Pin(typ.)

Pin(typ.)


97

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / h (%)

-0.5

0.0

0.5

1.0

1.5

V /

Vy

Brace Fuse Test 5CCWithout FuseWith Fuse

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / h (%)

-0.5

0.0

0.5

1.0

1.5

V /

Vy


280

280

40(typ.)

25.4 bolts@ 80x80 (typ.)

1034

Cut

BraceFuse

PL 6x63x250(2 sides)1

5-6



98


Fuses in W-Shapes (Canam Group, Montreal)


99



100


-5.0 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0 / hs

-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P / A

Fy

Design

Design

Cu

Tu

Test 1 - LF/LH = 0.11

-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 / hs

-1.2

-0.8

-0.4

0.0

0.4

0.8

1.2

P /

AFy

Design

Design

Cu

Tu

Test 3 - LF/LH = 0.07


101

Multi-Tiered Braced Frames


= 6.8

= 1.6

= 4.2

0.0 5.0 10.0 15.0 20.0Time (s)

-1.50-1.00-0.50

0.000.501.001.50

Drif

t (%

hn)

-1.50-1.00-0.50

0.000.501.001.50

Drif

t (%

hn)

Drift at h = 10.0 mDrift at h = 6.8 m

-1.0-0.50.00.51.0

Acc

el. (

g)

X-braced CBF vs Multi-tiered CBFs


102

2-tiered CBFsDesigned in accordance with AISC 341-10SCBF R = 6.0Los Angeles, CA - Site class D

Design Storey Drift (Cd/H) = 0.86% < 2%

Braces: HSS 102x102x6.4Columns: W310x174

Strut: W250x58



103

Design Storey (Cd)

1

2

Frame LateralDeformation

Column Shear &Bending Moment

Member Forces(axial loads in columns not shown)

u1

u2 u2

u1

1

c1c1

c2 c2

c1c1

c1 c1

T

T C

CV V

V V

MM

M M

H

2

c1

c2

c1

H

M

M

V

VVc c

1

2



104

Conclusions

Design provisions to achieve ductile seismic performance for building steel structures are now available for application in practice

Design objective is to prevent structural collapse and structural damage & residual deformations are expected

Some issues still need to be addressed Application of this design approach not

suitable for heavy industrial applications; specific design provisions needed for these structures


presentacion robert tremblay marzo 2014

Documents

polytechnique montreal

time s

braced frames moment

ductile seismic designhhwt

rdesign spectra design

frame systems

tensionyielding typ

industrial buildingsr