8.Lungu.et.al

COST C26: Urban Habitat Constructions under Catastrophic Events

Characteristics of strong ground Characteristics of strong ground

motion records in Romaniamotion records in Romania

WG2 Meeting in Timisoara, 26-27 October, 2007

motion records in Romaniamotion records in Romania

D. Lungu, C. Arion, A. Aldea and R. Vacareanu

Technical University of Civil Engineering, Bucharest

Strong motion modeling

１１１１））））Radiation from source

２２２２））））Attenuation in Crust and Mantle

３３３３））））Amplification at site

Local site

Physical process of wave generation in source to propagation from source to site

深部堆積深部堆積深部堆積深部堆積層層層層

source

Crust and Mantle Seismic bedrock

（basement）

Local site

Engineering

bedrockDeep

basin

World Map of Natural Hazards prepared by the Münich Re, 1998

indicates for Bucharest: “Large city with Mexico-city effect”

“The unusual nature of the ground motion and the extent and

distribution of the structural damage have important bearing

on earthquake engineering efforts in the United States.”

Jennings & Blume, NRC & EERI Report

"Nowhere else in the world is a center of population so exposed to

earthquakes originating repeatedly from the same source"

Charles Richter. 15 March 1977, Letter to the Romanian government

indicates for Bucharest: “Large city with Mexico-city effect”

Seismicity of Vrancea subcustral source (60-180 km) in

Carpathian Mountains

Intra-Alpine

subplate

East-European

plate

Vrancea

source

Hungary

Rep. of

Ukraine

subplate

Moesian subplate

Black Sea

subplateBucharest

source

Black

Sea

Bulgaria

Yugoslavia

Rep. of

Moldova

Seismic zones in Romania and epicenters

of earthquakes (984 to 2007)

1000 yr catalogue of Vrancea earthquakes

• Major historical events and major earthquakes in the XX century

Event

Epicentral intensity Io

Focus depth. km

Moment

magnitude Mw

Obs

1802, October 26 > 9 7.9 Largest Vrancea event ever occurred

≥≥≥≥≥≥≥≥

1802, October 26 1829, November 20 1838, June 23

> 9 8 8

7.9 Largest Vrancea event ever occurred

1940, November 10 1977, March 4 1986, August 30

9 8/9 7/8

150 109 133

7.7 7.5 7.2

Largest seismic losses ever experienced

Romania

Seismic networks

Station Comp. PGA

cm/s

Tc

s

INCERC NS 194.9 1.40s

March 4, 1977

seismic station INCERC

Bucharest

INCERC

O

NS

Z

EW

194.9

105.8

162.3

1.40s

1.20s

0.89s

First strong ground motion recorded in Romania

Norm

alized SA

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50March 4, 1977, INCERC Station in Bucharest

NS comp.

32 tall buildings completely collapsed

Period, s

0.000.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50

High dynamic amplification at long periods,

dangerous for high-rise buildings,

that makes Bucharest the

most dangerous capital city of Europe

Elastic response spectra for INCERC N-S’77 recordINCERC N-S'77

0

100

200

300

400

500

600

700

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

T , s

SA, cm

/s2

INCERC N-S'77

75

100

125

150

SV, cm

/s

ξξξξ =0,05

ξξξξ =0,05TC=1,34s INCERC N-S'77

500

600

700

ξξξξ =0,05

ADRS

0

25

50

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

T , s

SV

INCERC N-S'77

0

10

20

30

40

50

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

T , s

SD

, cm

ξξξξ =0,05

TD=1,90s

0

100

200

300

400

0 5 10 15 20 25 30 35 40

SD , cm

SA, cm

/s2

TC=1,34s

TD=1,90s

The recorded maximum peak ground acceleration in Romania

during 1977, 1986 and 1990 Vrancea earthquakes

%

#

#

&

%

#&

#

21 22 23 2425 26 27

28 29

48

47

Ukraine

Hungary Republic of Moldova

Moldova

Cris

Prut

#

#

#

Satu-Mare

Cluj-NapocaOradea

Iasi

Adjud

Bacau

Barlad

Dochia

Onesti

Botosani

Chisinau

Krasnogorka

Transilvania 86.6

11.5

50.9

82.0

132.0

168.6

212.8146.4

232.1

N

EW

S

200 - 300

150 - 200

75 - 150

0 - 75

PGA, cm/s2

ROMANIA. Maximum peak ground acceleration PGA, cm/s2 recorded during 1977, 1986 and 1990 VRANCEA earthquakes

Seismic stations with

free-field records:

# INCERC network

INFP network

#·

#·

#·

#·

#

%

%

%

$

#

%

###

#

#

#

#

&

#

$$

&

#

#

%

##

&

&

&

#

&

#

#

#

46

45

44

Yugoslavia

Bulgaria

BlackSea

Banat

Valahia

Mures

Danube

Dobrogea

#

#Craiova

Timisoara

Bucuresti

Turnu Magurele Ruse

Baia

Adjud

Peris

Varna

Surduc

Tulcea

Focsani

Istrita

Giurgiu

Otopeni

Pitesti

Kavarna

Campina

Branesti

Calarasi

Carcaliu

Provadia

Cernavoda

Vrancioaia

Vidra Lotru

Muntele Rosu

Bolintin Vale

Vidraru Arges

Transilvania

Cahul

Shabla

Fetesti

Ramnicu Sarat

1977

1986

1990

1940

86.6

79.1

97.2

45.8

14.3 26.1

90.8

36.2

48.2

32.9

93.6

33.6

61.5

297.1

109.4

186.9

157.2

208.6 150.8

194.9

114.1

223.8

112.4112.2

168.6

136.6

232.1

164.0

107.1100.4

158.6

#Constanta

Valenii de Munte

219.8

Ploiesti

Olt

#

100 0 100 200 Kilometers

ArcView GIS version 3.1, ESRI Inc. CA.

#· Epicenters of strong Vrancea events

(Mw > 6.9)

Lungu, Aldea, 1999

March 4, 1977

Mw=7.5h=109 km

Aug.30, 1986

May 30, 1990

Mw=7.2h=133 km

Mw=7.0h=91 km

Mw - moment magnitude

h - focus depth

& Bulgaria network

$ GEOTEC network

&

% INFP network

R. of Moldova network

Bucharest

Seismic networks

No. SiteStation

ID

Surface sensor

location

Depth of sensor

in shallow

borehole, m

Depth of

sensor in deep

borehole, m

Type of equipment

1 UTCB Tei UTC1 free field -28 -78

2 UTCB Pache UTC2 1 storey building -28 -66

3 NCSRR/INCERC INC 1 storey building -24 -153

4 Civil Protection Hdq. PRC 1 storey building -28 -68

5 Piata Victoriei VIC free field -28 -151

6 City Hall PRI free field -28 -52

7 Municipal Hospital SMU free field -30 -70

K2 +

FBA-23DH

(Kinemetrics)

Seismic instrumentation for

site response studies in Bucharest

7 Municipal Hospital SMU free field -30 -70

8 UTCB Plevnei UTC3 free field -30GSR24+AC23 DH

(Geosig)

Bucharest - Location of borehole instrumented sites

Borehole sensor

Altus K2

accelerometer

Borehole sensor

Free field

Shallow

borehole

24÷30m

Deep

borehole

60÷153m

Surface and

borehole cables

Borehole seismic instrumentation

20th

Free fieldborehole

BRD - Société Générale

bank headquarters

RC structure, 2002

19 storeysborehole

B3

Acceleration

-70

0

70

Acc. (cm/s/s) Top - transv. (peak:- 69.4 cm/s/s)

-70

0

70

Acc. (cm/s/s)

30 40 50 60 70 80 90 100 110 120 130 140 150Time (sec)

Basement - transv. (peak: 36.9 cm/s/s)

27 October, 2004 seismic event

PA, cm/s

2

Tc, s

Td, s

EPA, cm/s

2

EPV, cm/s

EPD, cm

f10, Hz

f50, Hz

f90, Hz

f90-f10, Hz

Characteristics of the horizontal components of motions

recorded by NCSRR seismic station BLD1

- 10 July 2004,Mw=4.3, h=150km,

- 27 Sept. 2004,Mw=4.6, h=166km,

- 27 Oct. 2004,Mw=6.0, h=99km,

- 14 May 2005,Mw=5.2, h=144km,

- 18 June 2005,Mw=5.0, h=135km,

- 8 Sept. 2005,Mw=4.3, h=140km.

cm/s2 s s cm/s

2 cm/s cm Hz Hz Hz Hz

SNS 1.61 0.23 0.35 1.36 0.05 0.003 3.03 5.08 9.96 6.93 07/10/2004 SEW 2.03 0.29 0.38 1.57 0.07 0.004 2.54 4.49 9.08 6.54

SNS 8.59 0.22 0.40 5.85 0.20 0.01 2.64 4.98 8.11 5.47 09/27/2004 SEW 7.62 0.30 0.44 7.13 0.34 0.02 2.25 4.39 7.62 5.37

SNS 22.26 0.31 0.62 22.57 1.13 0.11 1.46 3.13 8.30 6.84 10/27/2004 SEW 26.12 0.41 0.78 24.66 1.62 0.20 1.46 3.71 8.79 7.32

SNS 5.65 0.25 1.18 3.90 0.15 0.03 2.64 4.59 10.06 7.42 05/14/2005

SEW 6.33 0.28 0.69 4.89 0.22 0.02 1.76 4.49 8.30 6.54

SNS 6.99 0.29 0.46 5.58 0.25 0.02 2.44 4.39 7.62 5.18 06/18/2005 SEW 6.89 0.33 0.63 5.36 0.28 0.03 1.76 3.81 7.91 6.15

SNS 0.59 0.31 0.44 0.60 0.03 0.002 2.64 4.10 10.06 7.42 09/08/2005 SEW 1.29 0.30 0.38 0.99 0.05 0.003 2.64 3.42 7.91 5.27

#Y

#Y

#Y

CENTURA

ODAI

STEFANESTI

1 MAI

TUNARI

BANATULUI

PIPERA

RUDENI AF

UMATI

UNDENI

LACU

L TEI

NORDULUI

BUCURESTI - TIRGOVISTE

RE

GARII OB

STEFAN CEL MARE

TERASA COLENTINAGOL

CONSTANTA

PETRILA

TII

AVI ATORILOR

MARASTI

VIILOR

EREN

Titulescu87.5

219.8

156.0

Otopeni

#Y

#Y

#Y

CENTURA

ODAI

STEFANESTI

1 MAI

TUNARI

BANATULUI

PIPERA

RUDENI AF

UMATI

UNDENI

LACU

L TEI

NORDULUI

BUCURESTI - TIRGOVISTE

RE

GARII OB

STEFAN CEL MARE

TERASA COLENTINAGOL

CONSTANTA

PETRILA

TII

AVI ATORILOR

MARASTI

EREN

Otopeni

0.76

0.67

Titulescu

1.10

Bucharest. Aug. 30, 1986

Shake map for

PGA

Bucharest. Aug. 30, 1986

Microzonation of

control period Tc

#Y

#Y

$Z

#Y

#Y

#Y

#Y

%[

Colentina River

Dambovita River

ALEXA

NDRIE

I

BERCENI

PACII

SALAJ

UNIRII

PANTELIMON

TIMISOARA

CERNICA

OLTENITEI

FU

GHENCEA

RESSU CAMIL

PANDURI

LIBERTATII

IANCULUI

MIHAI BRAVU

REPUBLIC

II

VITAN BIRZESTI

UVERTURII

MARA

SESTI

ARII OBOR

CHISINAU

DECEBAL

COTRO

CENI

L MARE

PIEPTANARI

TINA

BUCURESTI - MAGURELE

GOLESCU

DINICU

VIRT

UTI

CENT

URA

CENTURA

CENTURA

MARASTI

VIILOR

INCERCPanduri

Militari ISPH/ARM

Metalurgiei

Drumul Sarii

Bucuresti-Magurele

86.896.2

71.7

95.3

100.6

135.4

Lungu, Aldea, 1999

#Y

#Y

$Z

#Y

#Y

#Y

#Y

%[

ALEXA

NDRIE

I

BERCENI

PACII

SALAJ

UNIRII

PANTELIMON

TIMISOARA

CERNICA

OLTENITEI

FU

GHENCEA

RESSU CAMIL

PANDURI

LIBERTATII

IANCULUI

MIHAI BRAVU

REPU

BLICII

VITAN BIRZESTI

UVERTURII

MARA

SESTI

ARII OBOR

CHISINAU

DECEBAL

COTRO

CENI

L MARE

PIEPTANA

RI

TINA

BUCURESTI - MAGURELE

GOLESCU

DINICU

VIRTUTI

CENT

URA

CENTURA

CENTURA

MARASTI

VIILOR

Militari

0.90INCERC

1.51

1.43

Metalurgiei

1.05

Bucuresti-Magurele

Drumul Sarii

Panduri

1.07

ISPH/ARM

1.26

1.10

Colentina river

Dambovita river

Lungu, Aldea, 1999

Lungu, D., Aldea, A., Demetriu, S., Arion, C., 2000. Zonation of seismic hazard for the city of Bucharest. Technical Report prepared for Association Française du Génie Parasismique, 59p.

Bucharest:

Microzonation map

for shear wave

velocity (m/s)

averaged on 30m

The values in the

range between

224m/s and 310m/s

Elastic response spectra for August 30, 1986

free-field seismic records in Bucharest

Bucuresti, 30 august 1986 - miscari inregistrate in free-field

500

600

700

INCERC

Balta Alba-SS

Carlton-SS2

EREN

Metalurgiei-P

Metrou - IMGB

Militari

ξξξξ =0,05

TC=1,42s

TD=1,83s

0

100

200

300

400

0.0 0.5 1.0 1.5 2.0 2.5 3.0T , s

Se, cm

/s2 Militari

Panduri

Titulescu

Otopeni-P

Bucuresti - ISPH

Bucuresti - Magurele

Bucuresti, 30 aug. 1986 - 16 miscari free-field

0

100

200

300

400

0.0 0.5 1.0 1.5 2.0 2.5 3.0

SA, cm

/s2

Valori medii

Valori medii+1abatere standard

ξξξξ =0,05 Bucuresti, 30 mai 1990 - 16 miscari free-field

0

100

200

300

400

500

0.0 0.5 1.0 1.5 2.0 2.5 3.0

SA, cm

/s2

Valori medii

Valori medii+1abatere standard

ξξξξ =0,05

Variability of free-field seismic records in Bucharest

T , s T , s

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.0 0.5 1.0 1.5 2.0 2.5 3.0

T , s

COV

SA

Bucuresti 1986

Bucuresti 1990

1986 earthquake (Mw=7.2) - maxSA(1.5s)

0

50

100

150

200

250

300

0 1 2 3

T, s

SA, cm

/s2

NS comp.

EW comp.

BUCHAREST

August 30, 1986 Mw =7.2

INCERC station

300

250

300

BUCHAREST

August 30, 1986 Mw =7.2

0

50

100

150

200

250

300

350

400

0 1 2 3

T , s

SA, cm/s

2

L comp.

T comp.

BUCHAREST

August 30, 1986 Mw =7.2

TITULESCU station

0

50

100

150

200

250

0 1 2 3

T , s

SA, cm

/s2

L comp.

T comp.

BUCHAREST

August 30, 1986 Mw =7.2

METALURGIEI station

0

50

100

150

200

250

300

0 1 2 3

T , s

SA, cm

/s2 L comp.

T comp.

BUCHAREST

August 30, 1986 Mw =7.2

METROU - IMGB station

0

50

100

150

200

250

0 1 2 3

T , s

SA, cm

/s2

N15E comp.

E15S comp.

August 30, 1986 Mw =7.2

ISPH station

0.0

1.0

2.0

3.0

4.0

0.0 1.0 2.0 3.0Period T , s

Norm

alized SA

BUCHAREST

Aug.30, 1986, M w=7.2

20 horiz. comp.

0.1 probability

of exceedance

0.5 probability

of exceedance

4.0

BUCHAREST

0.00

0.02

0.04

0.06

0.08

0.10

0 2 4 6 8 10Frequency f , Hz

Norm

alized m

edian PSD

Horiz. comp.M w=7.2

M w=6.3

M w=7.0

30 Aug. 1986, 22 comp.

30 May 1990, 22 comp.

31 May 1990, 12 comp.

0.0

1.0

2.0

3.0

0.0 1.0 2.0 3.0Period T , s

Norm

alized SA

BUCHAREST

May 30, 1990, M w=7.0

20 horiz. comp.

0.1 probability

of exceedance

0.5 probability

of exceedance

Mobility of average

normalized SA

Stronger earthquake

Narrower frequency band shifted

towards lower frequencies

Mobility of average

normalized PSD

2.0

2.5

3.0

3.5

Norm

ali

zed

SA

March 4, 1977

Aug. 30, 1986

May 30, 1990

INCERC, NS comp.

Mobility with magnitude of normalized SA spectrum for

INCERC seismic station, East of Bucharest

0.0

0.5

1.0

1.5

2.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5

Period T , s

Norm

ali

zed

M w=7.5

M w=7.0

M w=7.2

Normalized SA spectrum

for Bucharest records

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

Perioada T , s

SA norm

alizat

3.0

4 Martie 1977, comp. NS

PGA=1.95m/s 2

TC=1.5

TC=1.6 TD=2.0

4.8/T

9.6/T2

3.75/T

7.5/T2

Bucuresti

7 comp. orizontale

teren moale

0.1

0.5 probabilitate de depasire

2.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0Perioada T , s

SA norm

alizat

0.1 probabilitate de depasire

0.5

TC=0.5

TC=0.6

TD=3

1.92/T

5.76/T2

1.25/T

3.75/T2

Moldova & Republica Moldova

20 comp. orizontale

teren tare

30 Aug. 1986, Focsani, comp.EW

PGA=2.97 m/s 2

3.2

2.5

Normalized SA spectrum for

Moldova records

Banat crustal source

1.0

2.0

3.0

4.0

5.0

Spectru norm

alizat de acceleratii

Timisoara

8 comp. orizontale 3.5

3.0

2.1/T

1.5/T

media + 1 abatere standard

media

Normalised response spectra for

seismic records in Timisoara

0.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Perioada, T, s

media

0.0

1.0

2.0

3.0

4.0

5.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Perioada, T, s

Spectru norm

alizat de acceleratii

Banloc

2.5

2/T

20 componente orizontale

media + 1 abatere standard

media

Normalised response spectra for

seismic records in Banloc

Acc1_24

-0.25-0.20-0.15-0.10-0.050.000.050.100.150.200.25

0 5 10 15 20

t , s

a, 'g

Acc2_24

-0.25-0.20-0.15-0.10-0.050.000.050.100.150.200.25

0 5 10 15 20

t , s

a, 'g

Acc3_24

0.25

Acc4_24

0.25

Alternative description of seismic ground motion

artificial spectrum compatible accelerograms

-0.25-0.20-0.15-0.10-0.050.000.050.100.150.200.25

0 5 10 15 20

t , s

a, 'g

-0.25-0.20-0.15-0.10-0.050.000.050.100.150.200.25

0 5 10 15 20

t , s

a, 'g

Acc5_24

-0.25-0.20-0.15-0.10-0.050.000.050.100.150.200.25

0 5 10 15 20

t , s

a, 'g

a g =0.24g

0.5

0.6

0.7

0.8

0.9Acc1_24

Acc2_24

Acc3_24

Acc4_24

Acc5_24

Medie

P100-1/2006

Alternative description of seismic ground motion

artificial spectrum compatible accelerograms

0.0

0.1

0.2

0.3

0.4

0.5

0 1 2 3 4 5

T , s

Se, 'g

P100-1/2006

Seismic hazard analysis for Bucharest

( )( )( )0wmax,w

wmax,ww

MMe1

MMe1M

ewMn−−

−

−−−−=≥

β

ββα

Recurrence of magnitudes

Truncated Gutenberg-Richter law (McGuire & Arabasz, 1990)

Vrancea subcrustal source (Lungu et al., 2000)

)wM(tronqueeMf

w =

)MM(e1

)MM(e

0wmaxw

0ww

−−−

−−

β

ββ

Attenuation lawAttenuation law

Modele type - Molas & Yamazaki (1995)

ln PGA = c0 + c1 Mw + c2 lnR +c3R +c4 h + ε

PGA – peak ground accelerationMw- moment magnitude R – hypocentral distance h – focal depth c0, c1, c2, c3, c4 - coefficientsε - random variable with zero mean and st. dev.σε=σln PGA

Vrancea subcrustal source (Lungu et al., 2000)

Hazard curve (Cornell, 1968, Cramer, 1996)

P(PGA>PGA*|m,r) – annual exceedance probability of PGA* for an earthquake of magnitude Mw occuring at hypocentrale distance R and depth h

(PGA – lognormally distributed)

f(Mw) – probability density function of magnitude

f(R) – probability density function of hypocentrale distance

P[PGA>PGA*] = ∫∫∫ > dhdRwdM)h(f)R(f)wM(f]h,R,wM*PGAPGA[P

Vrancea subcrustal source (Vacareanu & Aldea, 2002)

f(h) – probability density function of focal depth

PSHA - Bucharest

1.E-04

1.E-03

1.E-02

1.E-01

100 150 200 250 300 350 400

PGA , cm/s2

Annual exceedance rate,

Π(PGA)

Uniform hazard spectrum for Bucharest

PSHA Bucharest - 475 yr. MRI

400

500

600

700

800

900

SA, cm

/s2

ξξξξ =0,05

0

100

200

300

0.0 0.5 1.0 1.5 2.0 2.5 3.0

T , s

Risk-UE Project

Probabilistic zonation of peak ground acceleration for design

P100/1-2006 Code: MRI =100 yr

Bucharest

MRI = 475 yr

PGA ≥ 0,35 g

Tp = 1.6

P100-1/2006 Control period of design spectra

T< TB

TB<T≤ TC β = β0

( )T

T

1 1

B

0 −+=

ββ

Normalised Response Spectra in EC8 format

P100-1/2006

0

0.5

1

1.5

2

2.5

3

3.5

0 0.5 1 1.5 2 2.5 3 3.5 4

Amplification factor

T D =3T C =0.7 T C =1 T C =1.6

T D =2

ξ =0.05

Vrancea subcrustal source

TB<T≤ TC β = β0

TC<T≤ TD

T> TD

T

TC0 ββ =

20 T

TT DC ⋅= ββ

0 0.5 1 1.5 2 2.5 3 3.5 4Period T , s

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

0 0.5 1 1.5 2 2.5 3 3.5 4Perioada T , s

T B=0.07s

2.1/T

β 0 =3

T C=0.7sT D=3

6.3/T2

Tc ? 0.7s

ξ =0.05

Banat crustal source