seismic performance of high-rise rc wall-type buildings in...

Seismic Performance of

High-rise RC Wall-type

Buildings in Korea

December 12th, 2014

Han Seon Lee

Professor, Korea University, Seoul, Korea

Structural Concrete Engineering Lab.

2

Introduction

7.9

13.4

22.6

37.5

47.752.5

58.4

0

10

20

30

40

50

60

70

1980 1985 1990 1995 2000 2005 2010

Rati

o o

f A

part

men

ts / T

ota

l (%

)

Year

Year 2010

Total No. of housing units: 14,577,419

Total No. of apartment units: 8,576,013

National Census

3

Introduction

A. Jamsil Els Apt.

in Seoul

(34-story)

B. Banpo Samsung

Raemian Firstige

Apt. in Seoul

(32-story)

C. Yongsan City Park

in Seoul (35-story)

D. Haeundae I’ Park

in Busan (72-story)

E. We’ve the Zenith

in Busan (80-story)

A B

C D E

4

Problems

Coupling beam Special boundary element

for shear wall

Mock-up test of special shear wall

(30-story residential building

in Daegu, Korea)

5

2010 Chile Earthquake (Mw 8.8)

S2 Compression

6

Spalling and crushing of concrete Creagh, A., Acevedo, C., Moehle, J., Hassan, W., & Tanyeri, A. C, “Seismic

performance of concrete special boundary element”, 2010 PEER Internship

Program & NEES Grand Challenge Project PEER Laboratory at UC Berkeley, 2010

0

600 kips

170 kips

183 kips

S1 Tension

S1 Comp

S2 Comp

2.52-1

S1 Compression

7

Spalling and crushing of concrete Yuniarsyah, E., Taleb, R., Kono, S., & Tani, M., “An experimental study on

confined RC wall boundary regions under uniaxial monotonic and cyclic reversal

loadings”, SEEBUS, 2014

Long: 10-D10

(ρg = 3.38%)

Trans: 3-D4@80

(ρw = 0.21%)

0.03m/m

9.33MPa

0.004m/m

33.3MPa

8

Earthquake simulation test

1:5 scale 10-story

RC wall-type

building model

2010

1:5 scale 9-story

RC piloti-type

building model

2011

1:15 scale 25-story

RC flat-plate core-wall

building model

2012

• To clarify the seismic response characteristics of

the RC high-rise residential building model by performing

earthquake-simulation tests on the small-scale models.

9

Procedure of this study…

1. 1:5 scale 10-story RC wall-type building model

2. Calibration of analytical model using PERFORM-3D through

comparison with shake-table results (Distorted model)

3. Evaluation of reliability of analysis (True replica model)

4. Effect of foundation flexibility

5. Effect of coupling beams and slabs

6. Evaluation of 10-story RC wall building structure

according to the analytical results

Prototype structures

10

Elevation Plan

• Design code: AIK2000

• Height: 27m(10-story)

• Weight: 21,270 kN

• Wall thick: 180/160mm

• Slab thick: 200mm

• Aw/Af (X-dir.) = 2.7%

• Aw/Af (Y-dir.) = 4.7%

• f’c = 24 MPa

• fy = 400 MPa

Ta = Ct (hn)3/4 = 0.865sec (X-dir.) and 0.580sec (Y-dir.)

V = Cs W = 1,530kN (X-dir.) and 2,300kN (Y-dir.)

117.0=/

dir.)-(Y .1080 and dir.)-(X 072.0=)/(

=1

E

DS

aE

D

S IR

S

TIR

SC ≤

W: weight, SD1, SDS: spectral accelerations at period 1sec and 0.2sec, respectively (0.234, 0.439),

R: response modification factor (4.5), IE: importance factor (1.2),

Ct = 0.073 (X-dir.): RC moment resisting frame (MRF), Ct = 0.049 (Y-dir.): other structures,

hn: height of structure (27m).

Base shear,

Base shear coefficient,

Fundamental period,

1:5 scale experimental model

11

Items

(unit: kN)

Total

Weight

Self

Weight

Added

Weight

Prototype 21,300 18,200 3,110

True

Replica

Model

(1:5)

851 145 705

Distorted

Model

(1:5) 425 145 280

PGA = 0.156g 54.4 sec-0.4

-0.2

0

0.2

0.4

0 10 20 30 40 50 60

Acc

el. (g

)

Time (sec)

Original Taft N21E (X-dir.)

PGA = 0.156g24.3 sec

-0.4

-0.2

0

0.2

0.4

0 10 20 30 40 50 60

Acc

el. (g

)

Time (sec)

True Replica Model (1:5 scale)

PGA = 0.311g17.2 sec

-0.4

-0.2

0

0.2

0.4

0 10 20 30 40 50 60

Acc

el. (g

)

Time (sec)

Distorted Model (1:5 scale)

Time × 1/√5

Accel. × 1

Time×1/√10

Accel.×2

1/2

* Maximum pay-load capacity of the shaking table = 600kN

Experimental setup

12

Shaking Table

Steel blocks

Reference Frame

LVDTs

Accelerometer

A2A1

A4A3

A6A5

A8A7

A10A9

A12A11

D15,D16,D29

D17,D18

D19,D20

D21,D22,D27

D23,D24

D25,D26

D28

D30

Independent Post

Shaking Table

Reference Frame

Independent Post

D1, D2

D3, D4

D5, D6

D7, D8

D9, D10

D11, D12

D14

D13

A13 A14

A15 A16

A17 A18

A19 A20

A21 A22

A23 A24

LVDTsSteel blocks

View A View B

Loadcell

Displacement transducers and accelerometers Footings and load cells at base

70mm x 70mm Plate

22mm Thread Bolt

Load Cell

Wall

Base Plate12mm bolt

Footing 170

D12

170

15

15D8

70

20

40

170

D12

170

15

15

80

15

40

100

120

80

90

75

55

D6

170

D12

170

15

15

80

15

40

90

60

50

D4

LC Type I LC Type II LC Type III


13

Test designation Intended PGA(g) Measured PGA(g) Return period in Korea

(year) X-dir. Y-dir. X-dir. Y-dir.

0.140X 0.140 - 0.172 - 50

0.140YY 0.140 0.161 0.137 0.142

0.374X 0.374 – 0.292 – Design Earthquake

(DE) 0.374XY 0.374 0.431 0.316 0.450

0.60X 0.60 – 0.523 – 2400 (MCE)

0.60XY 0.60 0.691 0.525 0.643

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8S

pect

ra a

ccel

erat

ion

(Sa)

Period (sec)

KBC2005 (DE)Output (Taft 0.374g X-dir.)Output (Taft 0.374g Y-dir.)KBC2005 (MCE)Output (Taft 0.60g X-dir.)Output (Taft 0.60g Y-dir.)

MCE

DE (R=1.0, IE=1.0)

1952 Taft N21E (X-dir.) Taft S69E (Y-dir.)

14


15

Nonlinear dynamic time history analysis

X-dir.(+)

Y-dir. (+)

0 200 400 600 800

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

Time (sec)

Acc

eler

atio

n (

g)

0.07g0.140g

0.308g 0.374g 0.6g

Taft S69E, Y-dir.

(Distorted model)

Duration: 733 sec

0 200 400 600 800 1000-0.4

-0.2

0

0.2

0.4

Time (sec)

Acc

eler

atio

n (

g)

0.035g0.07g 0.154g 0.187g

0.3g

Taft S69E, Y-dir.

(True replica model)

Duration: 1037 sec

0.401 g

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 10 20 30 40 50 60

Acc

eler

atio

n (

g)

Time (s)

Ground acceleration

recorded in Conception, 2010

Longitudinal component, X-dir.

(Duration: 63.36 sec)

-0.286

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 10 20 30 40 50 60

Acc

eler

atio

n (

g)

Time (s)

Ground acceleration


Transversal component, Y-dir.


-0.367 g-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 10 20 30 40 50 60

Acc

eler

atio

n (

g)

Time (s)

Ground acceleration


Vertical component, Z-dir.


0 200 400 600 800

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

Time (sec)

Acc

eler

atio

n (

g)

0.07g0.140g

0.308g 0.374g 0.6g

Taft N21E, X-dir.

(Distorted model)

Duration: 733 sec

0 200 400 600 800 1000-0.4

-0.2

0

0.2

0.4

Time (sec)

Acc

eler

atio

n (

g)

0.035g0.07g 0.154g 0.187g 0.3g

Taft N21E, X-dir.

(True replica model)Duration: 1037 sec

Recorded table excitations used for analysis

• 1952 Taft EQ. for distorted model (test, analysis)

• 1952 Taft EQ. for true replica model (analysis)

• 2010 Concepcion EQ. for true replica model (analysis)

16

Analytical modeling – “Wall”

-30

-20

-10

0

-0.01 -0.005 0 0.005 0.01

Str

ess

(MP

a)

Strain (mm/mm)

Thorenfeldt model

Perform-3D model

Ec = 23,700MPa

f'c = 25.5MPa

-600

-400

-200

0

200

400

600

-0.1 -0.05 0 0.05 0.1

Str

ess

(MP

a)

Strain (mm/mm)

ϕ2D3

Es = 200,000MPa

fy, ϕ2 = 423MPa

fy, D3 = 489MPa

0

0.5

1

1.5

2

2.5

3

0 0.005 0.01 0.015 0.02

Sh

ear

stre

ss (

MP

a)

Shear strain (mm/mm)

ASCE/SEI 41-06

Analytical modelvn = 2.49MPa

Gc = 0.4Ec = 9,490MPa

0.2vn

Geff = 0.5Gc= 4,750MPa

vn = 1.25 MPa

Concrete

Steel

Concrete Shear

Concrete Shear

Others (elastic)

Conc.

Steel

Fiber sections : Axial and in-plane bending behaviors

in the longitudinal direction

: Inelastic shear behaviors

: Transverse in-plane bending behavior

Shear Wall Ele. 4 nodes (24 d.o.f.)

“Inelastic Shear Wall” element

17

Analytical modeling – “Slab” & “Coupling beam”

“Slab” and “Coupling beam”: Inelastic beam elements

Imbedded column (rigid zone)

Plastic hinge (M-ϕ) Elastic section

Stiff end zone

Plastic hinge (M-ϕ) Shear hinge

Stiff end zone

18

Calibration of Analytical Model

-0.3

-0.15

0

0.15

0.3

0 2 4 6 8 10

V/W

Time (sec)

EXP. Anal.

Base shear / Building weight, V/W (X-dir.)

-0.3

-0.15

0

0.15

0.3

0 2 4 6 8 10

V/W

Time (sec)

EXP. Anal.

Base shear / Building weight, V/W (Y-dir.)

-0.6

-0.3

0

0.3

0.6

0 2 4 6 8 10

Roof

dri

ft (

%)

Time (sec)

EXP. Anal.

Roof drift (X-dir.)

-0.6

-0.3

0

0.3

0.6

0 2 4 6 8 10

Roof

dri

ft (

%)

Time (sec)

EXP. Anal.

Roof drift (Y-dir.)

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)

EXP. Anal.

Overturning moment in X-dir.

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)

EXP. Anal.

Overturning moment in Y-dir.

-0.3

-0.15

0

0.15

0.3

0 2 4 6 8 10

V/W

Time (sec)

EXP. Anal.

Base shear / Building weight, V/W (X-dir.)

-0.3

-0.15

0

0.15

0.3

0 2 4 6 8 10

V/W

Time (sec)

EXP. Anal.

Base shear / Building weight, V/W (Y-dir.)

-0.6

-0.3

0

0.3

0.6

0 2 4 6 8 10

Roof

dri

ft (

%)

Time (sec)

EXP. Anal.

Roof drift (X-dir.)

-0.6

-0.3

0

0.3

0.6

0 2 4 6 8 10

Roof

dri

ft (

%)

Time (sec)

EXP. Anal.

Roof drift (Y-dir.)

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)

EXP. Anal.

Overturning moment in X-dir.

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)

EXP. Anal.

Overturning moment in Y-dir.

Desi

gn E

art

hquake (

DE)

in K

ore

a

Maxim

um

Consi

dere

d E

art

hquake (

MCE)

in K

ore

a

19

Calibration of Analytical Model

MCE DE SLE

Distorted model (EXP: gray, ANAL: orange) vs. True replica model (black)

Analytical modeling – foundation flexibility

Type of

load cell

Axial stiffness (kN/mm)

Tension Compression

LC Type I 690 1380

LC Type II 1,630 3,260

LC Type III 5,030 10,060

1

Axial Stiffness of Load cells Soil-Structural Interaction Class C: very dense soil and soft rock vs: shear wave velocity (500m/s), G0 : initial soil shear modulus (510 MPa),

ν: Poisson ratio (0.3 for sand). ρs: soil mass density (20kN/m3/g)

G = αG0 = αvs2ρs

= 317 MPa

ASCE 41-13

Kend = 1,580kN/mm

(LC 1)

21

Effect of foundation flexibility

Concepcion EQ. MCE in Korea DE in Korea

-0.4

-0.2

0

0.2

0.4

-0.6 -0.3 0 0.3 0.6

V/W

Roof drift (%)

Flexible-base

Fixed-base

X-dir.

DE in Korea

-0.4

-0.2

0

0.2

0.4

-0.6 -0.3 0 0.3 0.6

V/W

Roof drift (%)

Flexible-base

Fixed-base

X-dir.

MCE in Korea

-0.4

-0.2

0

0.2

0.4

-4 -2 0 2 4

V/W

Roof drift (%)

Flexible-baseFixed-base

X-dir. Concepcion EQ.

-0.4

-0.2

0

0.2

0.4

-0.6 -0.3 0 0.3 0.6

V/W

Roof drift (%)

Flexible-base

Fixed-base

Y-dir.

MCE in Korea

-0.4

-0.2

0

0.2

0.4

-0.6 -0.3 0 0.3 0.6V

/WRoof drift (%)

Flexible-baseFixed-base

Y-dir.Concepcion EQ.

-0.4

-0.2

0

0.2

0.4

-0.6 -0.3 0 0.3 0.6

V/W

Roof drift (%)

Flexible-base

Fixed-base

Y-dir.

DE in Korea

• Flexible-base (blue-line) vs. Fixed-base (black-line)

22

Effect of foundation flexibility – drift

• Flexible-base (solid-line) vs. Fixed-base (dotted-line)

0.271-0.19

1

3

5

7

9

11

-0.6 -0.3 0 0.3 0.6

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

Footing

Rotation

Roof

MCE

in Korea

(Y-dir.)

Roof0.11-0.18

1

3

5

7

9

11

-0.6 -0.3 0 0.3 0.6

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

Footing

Rotation

Roof

MCE

in Korea

(X-dir.)

Roof

MCE in Korea

1

3

5

7

9

11

-1 -0.5 0 0.5 1

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

RoofMCE

in Korea

(X-dir.)

Roof

1

3

5

7

9

11

-1 -0.5 0 0.5 1

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

RoofMCE

in Korea

(Y-dir.)

Roof

0.158-0.138

1

3

5

7

9

11

-0.6 -0.3 0 0.3 0.6

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

Footing

Rotation

Roof

Concepcion

EQ.

(Y-dir.)

Roof0.32-0.33

1

3

5

7

9

11

-3 -1.5 0 1.5 3

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

Footing

Rotation

Roof

Concepcion

EQ.

(X-dir.)

Roof

2010 Concepcion EQ.

1

3

5

7

9

11

-4 -2 0 2 4

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

RoofConcepcion

EQ.

(X-dir.)

Roof

1

3

5

7

9

11

-1 -0.5 0 0.5 1

Flo

or

Drift (%)

Flexible-

base

Fixed-

base

RoofConcepcion

EQ.

(Y-dir.)

Roof

Late

ral defl

ecti

on

Inte

rsto

ry d

rift

23

Effect of foundation flexibility – drift

• Flexible-base vs. Fixed-base models

MCE in Korea

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)

TotalPor. 1+6Por. 2+5+7+9Por. 3+4+8

Fixed-base

MCE

in Korea

at max.

base shear

(X-dir.)

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Fixed-base

MCE

in Korea

at max.

base shear

(Y-dir.)

Fixed-base Flexible-base

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Flexible-base

MCE

in Korea

at max.

base shear

(X-dir.)

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Flexible-base

MCE

in Korea

at max.

base shear

(Y-dir.)

2010 Concepcion EQ.

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Fixed-base

MCE

in Korea

at max.

base shear

(X-dir.)

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Fixed-base

MCE

in Korea

at max.

base shear

(Y-dir.)


1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Flexible-base

MCE

in Korea

at max.

base shear

(X-dir.)

1

2

3

4

5

6

7

8

9

10

-300 -150 0 150 300

Sto

ry

Shear force (kN)


Flexible-base

MCE

in Korea

at max.

base shear

(Y-dir.)

X-d

ir.

Y-d

ir.

24

Damage Pattern of the Wall and Slab in Experiment

Third

Floor

upper

side

Third

Floor

lower

side

25

Damage Pattern of the Wall

AB C

ED

A B C

D E

26

Effects of Slabs and Coupling Beams

To investigate the influence of the slab and coupling beam,

the models with/without slabs (Models SB/NS) are also modeled.

0

0.05

0.1

0.15

0.2

0.25

0.3

0 0.005 0.01 0.015 0.02 0.025

Bas

e sh

ear

/ B

uil

din

g w

eig

ht

Roof drift (ratio)

SB, flexible-baseSB, fixed-baseNS, flexible-baseNS, fixed-base

X-dir. (+)

Steel, ε = 0.002m/m

Shear stress degradation

in wall, ε = 0.01m/m

Concrete, ε = 0.002m/m

Concrete, εc,ult = 0.006m/m

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.0025 0.005 0.0075 0.01 0.0125 0.015

Bas

e sh

ear

/ B

uil

din

g w

eig

ht

Roof drift (ratio)

SB, flexible-baseSB, fixed-baseNS, flexible-baseNS, fixed-base

Y-dir. (+)

Steel, ε = 0.002m/m

Shear stress degradation

in wall, ε = 0.01m/m

Concrete, ε = 0.002m/m

Concrete, εc,ult = 0.006m/m

X-dir. SB NS

Flexible-

base

Period 0.433s 0.552s

Kinitial 7.89 4.31

Fixed-

base


Kinitial 15.3 10.6

Y-dir. SB NS

Flexible-

base


Kinitial 18.6 14.4

Fixed-

base


Kinitial 64.9 56.6

Unit of Kinitial : kN/mm

27

Contribution of Slabs and Coupling Beams

∑Fjhj = ∑Mi + ∑Pili

Degree of coupling (d.o.c) = ∑

∑

jj

ii

hF

lP

True replica

model

Table

excitation

Total OTM

(∑Fjhj)

OTM due to

T/C coupling

(∑Pili)

d.o.c

(∑Pili/∑Fjhj)

Model

SB

Flexible-

base

Taft 0.187XY (DE) 418 208 49.8%

Taft 0.3XY (MCE) 561 272 48.5%

Concepcion EQ. 1025 473 46.1%

Fixed-

base

Taft 0.187XY 395 177 44.7%

Taft 0.3XY (MCE) 494 247 50.1%


Model

NS

Flexible-

base

Taft 0.187XY (DE) 293 59.2 20.2%

Taft 0.3XY (MCE) 417 102 24.5%


Fixed-

base

Taft 0.187XY (DE) 290 66.2 22.8%

Taft 0.3XY (MCE) 393 119 30.3%


• Maximum overturning moment, OTM (unit: kNm)

∑Fjhj: external overturning moment

∑Mi: the sum of the base moments

∑Pili: the sum of the values of the axial force

multiplied by the arm length

28

0.30

-0.54

0.11

-0.18

-1

-0.5

0

0.5

1

0 2 4 6 8 10

Dri

ft (

%)

Time (sec)

Roof drift (X-dir.)Rotation of footing (X-dir.)

MCE in KoreaFlexible-base

Model

SB

406

-561

223 (55.1%)

-272 (48.5%)

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)

Total OTM (X-dir.)OTM due to T/C coupling

0.00123

-0.001

0

0.001

0.002

0.003

0 2 4 6 8 10

Str

ain

(m

/m)

Time (sec)

LW1 RW1

-20

-10

0

10

-0.005 0 0.005

Str

ess

(MP

a)

Strain (m/m)

LW1-20

-10

0

10

-0.005 0 0.005

Str

ess

(MP

a)

Strain (m/m)

RW1

Fle

xib

le-b

ase

model under

MCE in K

ore

a 0.32

-0.32

-1

-0.5

0

0.5

1

0 2 4 6 8 10

Dri

ft (

%)

Time (sec)

Roof drift (X-dir.)

MCE in KoreaFixed-base

Model

SB

479

-494

245 (51.2%)

-247 (50.1%)

-1000

-500

0

500

1000

0 2 4 6 8 10

OT

M (

kN

m)

Time (sec)


0.00119

-0.001

0

0.001

0.002

0.003

0 2 4 6 8 10S

trai

n (

m/m

)

Time (sec)

LW1 RW1

-20

-10

0

10

-0.005 0 0.005

Str

ess

(MP

a)

Strain (m/m)

LW1-20

-10

0

10

-0.005 0 0.005

Str

ess

(MP

a)

Strain (m/m)

RW1

Fix

ed-b

ase

model under

MCE in K

ore

a

• Time histories (MCE):

Roof drift (X-dir.)

OTM (X-dir.)

Axial strain (LW1, RW1)

LW1 RW1

Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

Plastic hinge

2F

3F

1F

LW1

RW1

0.0122

-20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

LW1

0.0144

-20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

RW1

0.0112

-20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

LW1

0.0103

-20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

RW1

2.44

-2.71

0.32

-0.33

-4

-2

0

2

4

6 9 12 15 18 21 24

Dri

ft (

%)

Time (sec)

Roof drift (X-dir.)Rotation of footing (X-dir.)

Concepcion EQ.Flexible-base

Model

SB

822

-778

307 (37.4%)

-251 (32.3%)

-1200

-600

0

600

1200

6 9 12 15 18 21 24

OT

M (

kN

m)

Time (sec)


0.0122 0.0144

-0.005

0

0.005

0.01

0.015

0.02

6 9 12 15 18 21 24

Str

ain

(m

/m)

Time (sec)

LW1 RW1

1.65

-1.70

-4

-2

0

2

4

6 9 12 15 18 21 24

Dri

ft (

%)

Time (sec)

Roof drift (X-dir.)

Concepcion EQ.Fixed-base

Model

SB

737

-875

297 (40.3%)

-405 (46.3%)

-1200

-600

0

600

1200

6 9 12 15 18 21 24

OT

M (

kN

m)

Time (sec)


0.0112 0.0103

-0.005

0

0.005

0.01

0.015

0.02

6 9 12 15 18 21 24S

trai

n (

m/m

)

Time (sec)

LW1 RW1

29

Fle

xib

le-b

ase

model under

Concepcio

n E

Q.

Fix

ed-b

ase

model under

Concepcio

n E

Q.

• Time histories (C.E.):

Roof drift (X-dir.)

OTM (X-dir.)

Axial strain (LW1, RW1)

LW1 RW1

Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

Plastic hinge

2F

3F

1F

LW1

RW1

-0.00089

0.00528

-20

-10

0

10

-0.006 0 0.006

Str

ess

(MP

a)

Strain (m/m)

X6Y1

0.00381

-0.00076 -20

-10

0

10

-0.006 0 0.006

Str

ess

(MP

a)

Strain (m/m)

X6Y6

30

Maximum axial strain demand (MCE in Korea)

0.00528 0.00412

-0.0009 1

3

5

7

9

11

-0.003 0 0.003 0.006 0.009

Flo

or

Axial Strain (m/m)

Flexible-base

(X6Y1)

Flexible-base

(X6Y10)

Fixed-base

(X6Y1)

Fixed-base

(X6Y10)

MCE in KoreaRoof

0.00381 0.00226

-0.0008 1

3

5

7

9

11

-0.003 0 0.003 0.006 0.009

Flo

or

Axial Strain (m/m)

Flexible-base

(X1Y6)Flexible-base

(X6Y6)Fixed-base

(X1Y6)Fixed-base

(X6Y6)

MCE in KoreaRoof

Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

X6Y1 X6Y6

-0.0013

0.0243

-20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

X6Y1

0.0252

-0.00686 -20

-10

0

10

-0.01 0 0.01 0.02 0.03

Str

ess

(MP

a)

Strain (m/m)

X6Y6

0.0128 0.0217 0.0243

0.0196

-0.00134 1

3

5

7

9

11

-0.01 0 0.01 0.02 0.03

Flo

or

Axial Strain (m/m)

Flexible-base

(X6Y1)

Flexible-base

(X6Y10)

Fixed-base

(X6Y1)

Fixed-base

(X6Y10)

Concepcion EQ.Roof

0.0252 0.0161 -0.0069

1

3

5

7

9

11

-0.01 0 0.01 0.02 0.03

Flo

or

Axial Strain (m/m)

Flexible-base

(X1Y6)Flexible-base

(X6Y6)Fixed-base

(X1Y6)Fixed-base

(X6Y6)

Concepcion EQ.Roof

31

Maximum axial strain demand (Concepcion EQ.)

Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

X6Y1 X6Y6

-0.0010

0.0017

-20

-10

0

10

-0.004-0.002 0 0.002 0.004

Str

ess

(MP

a)

Strain (m/m)

X4Y4-0.0012

0.0015

-20

-10

0

10

-0.004-0.002 0 0.002 0.004

Str

ess

(MP

a)

Strain (m/m)

X4Y4

32

Model SB, Flexible-base

Instant: 2.31s (max. roof drift (-X))

under MCE in Korea

Y1 Y2Y3 Y4Y5 Y6Y7 Y8Y9 Y10

Model SB, Fixed-base


under MCE in Korea

Y1 Y2Y3 Y4Y5 Y6 Y7 Y8Y9 Y10

-0.00119 0.00215

1

2

3

4

5

-0.003 -0.0015 0 0.0015 0.003

Flo

or

Axial Strain (m/m)

Y2

Y4

Y7

Y9

Flexible-base

MCE

in Korea

(2.31s)

0.00211 -0.00089

1

2

3

4

5

-0.003 -0.0015 0 0.0015 0.003

Flo

or

Axial Strain (m/m)

Y2

Y4

Y7

Y9

Fixed-base

MCE

in Korea

(2.28s)

MCE in Korea



Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

Plastic hinges and axial strain in Frame X4 at instant max. roof drift (-X)

Y1 Y2Y3 Y4Y5 Y6Y7 Y8Y9 Y10

Model SB, Flexible-base


under 2010 Concepcion earthquake

Y1 Y2Y3 Y4Y5 Y6Y7 Y8 Y9 Y10

Model SB, Fixed-base


under 2010 Concepcion earthquake

-0.0154 0.0236

1

2

3

4

5

-0.03-0.02-0.01 0 0.01 0.02 0.03

Flo

or

Axial Strain (m/m)

Y2

Y4

Y7

Y9

Flexible-base

Concepcion

EQ.

(10.81s)

0.0161 -0.0080

1

2

3

4

5

-0.03-0.02-0.01 0 0.01 0.02 0.03

Flo

or

Axial Strain (m/m)

Y2

Y4

Y7

Y9

Fixed-base

Concepcion

EQ.

(11.55s)

2010 Concepcion EQ.


33

-0.0092

0.0153

-20

-10

0

10

-0.03-0.015 0 0.015 0.03

Str

ess

(MP

a)

Strain (m/m)

X4Y4-0.0155

0.0250

-20

-10

0

10

-0.03-0.015 0 0.015 0.03

Str

ess

(MP

a)

Strain (m/m)

X4Y4


Y1 Y2 Y3 Y4Y5 Y7Y6 Y8Y9 Y10

X1

X2

X3

X4

X5

X6

Plastic hinges and axial strain in Frame X4 at instant max. roof drift (-X)

Effect of foundation flexibility

The flexible foundation significantly decreases the initial stiffness

with lengthening the fundamental period.

The maximum roof drift of the flexible-base model is larger than that of

the fixed-base model, whereas the maximum base shear of the flexible-

base model are similar to that of the fixed-base model.

The interstory drifts under MCE in Korea within 0.6%,

which satisfy the allowable interstory drift limit, 1.5%,

defined by KBC 2009 (IBC 2006).

The maximum interstory drifts in flexible-base model are 1.5~2.5

times larger than those in fixed-base model.

In particular, the translational behavior in the Y direction (the ratio of

wall cross sectional area to building floor plan area, Aw/Af = 4.71%)

is more sensitive to the motion of foundation rocking than

that in the X direction (Aw/Af = 2.67%).

Conclusions (1/2)

34

Effect of coupling beams and slabs

In the models without slab and coupling elements,

the natural period, initial stiffness, and maximum strength representing

the global responses are considerably lower than those of the model

with slab and coupling beam elements.

For the design, therefore, the analytical model of the box-type wall

building structure ignoring the flexural rigidity of the slab and

coupling beam could provide the erroneous information for design.

Models with and without slab elements are governed by the membrane

actions due to the coupling effect of the web wall to the flange wall.

In the analytical model with slabs, the coupling behavior of walls

covers approximately 40~50% of the total overturning moment, with

that in the model without slabs resisting about 20~30% of the total.

Therefore, the membrane action due to the slab and coupling beam

contribution can increase significantly the demand of the overturning

moment.

Conclusions (2/2)

35

Thank you

for your attention!

The research presented herein was supported by the National Research Foundation

of Korea (NRF-2009-0078771) and Architecture & Urban Development Research

Program funded by Ministry of Land, Infrastructure and Transport of Korean

government (13AUDP-B066083-01). The writers are grateful for this support.

36

seismic performance of high-rise rc wall-type buildings in...

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