Transcript Seismic risk mitigation in the Vrancea region, Romania WORLD BANK Workshop

Hazard Risk Mitigation in Europe and Central Asia
WORLD BANK Workshop
Istanbul, October 26-28, 2004
Seismic risk mitigation in the
Vrancea region, Romania
Dan Lungu
Technical University of Civil Engineering, Bucharest and
National Institute for Building Research, Bucharest
Original Presentation has been modified for Internet
Use.
Contents
1. The Romanian earthquake hazard and the 1977 disaster
in Bucharest
2. Vulnerability (fragility) of existing building stock and Codes for
earthquake resistance of buildings
3. National programs and international projects for seismic risk
mitigation in Romania
1. The Romanian earthquake hazard and the 1977
disaster in Bucharest
"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
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
1000 yr catalogue of Vrancea earthquakes
• Major historical events and major 20 century earthquakes
Event
1802,
1829,
1838,
1940,
1977,
1986,
October 26
November 20
June 23
November 10
March 4
August 30
Epicentral
intensity Io
>9
≥8
≥8
9
8/9
7/8
Focus
depth.
km
150
109
133
Moment
magnitude Mw
Obs
7.9
Largest Vrancea event ever occurred
7.7
7.5
7.2
Largest seismic losses ever experienced
• Number of events/century, having intensity larger than 9 and 7
Epicentral intensity
(MSK)
Catalogue time span, years
984 - 1900
1901 - 2000
I0≥ 9.0
1
2
I0 ≥ 7.0
10
16
Obs
20 century shows the highest
seismic activity of the Vrancea
source
March 4, 1977 earthquake
Mw = 7.7 ; h = 109 km
Killed 1,578 people (1424 in Bucharest)
Injured 11,221 people (7598 in Bucharest)
• Destroyed or seriously damaged 33,000 housing units and
caused lesser damage to 182,000 other dwellings
• Destroyed 11 hospitals and damaged 448 others hospitals, etc.
The World Bank estimation of losses (Report 16.P-2240-RO, 1978):
• Total losses in Romania
: 2.05 billion USD
(100%)
: 1.42
(70%)
Building and housing losses : 1.02
(50%)
Construction losses
PSHA, Probabilistic seismic hazard assessment
Lungu, Demetriu, 1994-2004
1. Recurrence of Vrancea magnitude
Date
Moment
magnitude,
Mw
 (  Mw)  1
8.0
7.9
475 yr
10 Nov 1940
7.7
7.6
100 yr
4 March 1977
7.5
7.3
7.2
50 yr
26 Oct 1802
30 Aug 1986
Mean recurrence interval
1
 1.687(M
M )
w,max
w
8.654  1.687M
w 1 e
e
 1 .687(M
M
)
w,max
w,o
1e
778 yr
356
148
108
82
50
40
2. Attenuation of Vrancea strong ground motion
lnPGA  3.098 1.053M 1.000lnR  0.0005R  0.006h  0.502
w
PGA - peak ground acceleration at the site
Mw- moment magnitude: Mw,0 = 6.3 Lower threshold magnitude; Mw, max= 8.1 Max credible
R - hypocentral distance to the site; h - focal depth;
ln PGA= 0.502- standard deviation of lnPGA
Database: 80 triaxial records at 48 free-field stations in Romania, R. of Moldavia, Bulgaria
2. Vulnerability (fragility) of existing building stock
and Codes for earthquake resistance of buildings
Quality of seismic design incorporated into existing buildings stock is
modeled by four categories :
Pre-code; Low-code; Moderate-code; High-code.
MSK intensity,
from seismic
zonation map
Period of construction of building
before
1940
1941-1963
1964-1977
1978-1990
after 1990
VI
VII
VIII, Bucharest
IX
Precode
Lowcode
Moderate-high
code
3 International lessons unlearnt from the 1977 earthquake
1
“A systematic evaluation should be made of all buildings in Bucharest erected prior to
the adoption of earthquake design requirements and a hazard abatement plan should
be developed.”
From:
“Observation on the behaviour of buildings in the Romanian earthquake of March 4, 1977” by G. Fattal, E. Simiu and Ch.
Cluver. Edited as the NBS Special Publication 490, US Dept of Commerce, National Bureau of Standards, Sept 1977.
2
“Tentative provisions for consolidation solutions would preferably be developed
urgently”.
From:
“The Romanian earthquake. Survey report by Survey group of experts and specialists dispatched by the Government of
Japan (K. Nakano). Edited by JICA, Japan International Cooperation Agency, June 1977.
3
“Bucharest had been microzoned as part of UNESCO Balkan Project, with microzones
denoting three levels of risk. The worst destruction occurred in lowest-risk microzone.”
From:
“”Earthquake in Romania March 4,1977. An Engineering Report” by G. Berg, B. Bolt, M. Sozen, Ch. Rojahn. Edited by
National Academy Press, Washington, D.C. 1980
The 1977 National strategy for strengthening
damaged buildings
“The retrofitting of buildings must provide:
(i) For the old buildings – the same resistance the have before 1940
earthquake (when they survived!);
(ii) For the new buildings – the same resistance the have when they were
designed”
Letter to the Municipality of Bucharest of the General Inspector for
Construction of Romania, based on March 30, 1977, Order of
Romanian Government
“Retrofitting of the buildings damaged by the 1977 earthquake will consist of
strict local repairing of damaged elements. Additional measures for
seismic protection are not allowed.”
Letter to the technical University of Civil Engineering, Bucharest from
General Inspector for Construction of Romania and General
Director of Central Institute for Research Design and Coordinator for
Construction, July 11, 1977
Seismic risk class Matrix
Vulnerability
class
i
ii
iii
“Seismic risk class 1
buildings”
Importance and exposure class
I
1
1
II
1
2
III
2
3
IV
3
3
3
Building to be immediately retrofitted!
Vulnerable residential buildings
-from Ministry of Transports, Constructions and Tourism of RomaniaCity
Number of vulnerable
buildings
Number of
inhabitants
Bacau
6
208.643
Barlad
6
78.786
Braila
4
232.409
Brasov
8
312.481
123+ ...
2.011.305
Buzau
1
146.926
Campina
2
40.297
Iasi
49
347.606
Roman
1
81.731
Suceava
1
118.183
Targu-Mures
Vaslui
1
6
164.132
78.735
Bucharest
Vulnerable school buildings
-from Ministry of Education and Research of RomaniaNumber of vulnerable schools
City
Total
Requiring
technical
assessment
Having a
technical
report
Having
technical
documents
Bacau
Barlad
Brasov
Bucharest
Constanta
Craiova
Galati
Giurgiu
Iasi
Pitesti
Ploiesti
Sibiu
Vaslui
1
11
7
13
2
1
2
3
1
3
10
2
7
2
5
1
5
1
-
2
1
5
1
-
1
11
9
22
1
7
3
2
8
2
6
4
10
Total
54
23
9
86
Vulnerable hospital buildings
-from Ministry of Health and Family of Romania-
Number of vulnerable hospitals
CITY
Bacau
Barlad
Bucharest
Buzau
Constanta
Craiova
Focsani
Galati
Giurgiu
Iasi
Pitesti
Ploiesti
Sibiu
Targu-Mures
Vaslui
Total
Severely damaged.
Requiring immediate
technical assessment
Having a technical
report
Approved project
for retrofitting
Retrofitting in
work
3
13
9
7
4
21
2
2
1
2
4
68
16
6
1
17
7
47
1
3
2
45
9
7
4
2
9
1
45
9
2
1
2
5
19
146
6
2
10
2
2
1
2
5
12
Total
3. National programs and International projects for
seismic risk mitigation in Romania
Objectives:
1. Strengthening of “seismic risk class 1” buildings:
Legislation + Construction work;
2. Upgrading of the code for seismic design of buildings and
structures;
3. Seismic instrumentation
Strengthening work for the 123 highly
vulnerable buildings in Bucharest
October 2004:
3 buildings are fully retrofitted
8 buildings are under retrofitting
16 buildings have retrofitting projects ready
8 buildings are on the waiting list for retrofitting
Upgrading the code for seismic design of buildings and
structures
The draft of the New code for earthquake resistance of new structures,
P100-2004, following EUROCODE 8 format, was just issued (Jan 2004)
The draft of the New code for earthquake resistance of existing buildings
and structures: to be prepared !
Seismic instrumentation in Romania, 2004
Name of network
INCERC & ISC, State
Inspectorate for
New digital
Construction
networks, installed in CNRRS & JICA,
2003
Japan International
Cooperation Agency
1
Project
Existing seismic
networks, in 2002
TOTAL
instruments
Bucharest
Romania
(including Bucharest)
7 ETNA
31 ETNA
11 K2
16 instruments:
-11 K2;
- 5 ETNA
INCERC
21 instruments:
-10 SMA-1 (analog)
- 9 ADS (digital)
-2 digital stations for
continuous monitoring
70 instruments:
-58 SMA-1(analog)
- 9 ADS (digital)
3 digital station for
continuous monitoring
INFP/SFB 461
German Science
Foundation Project at
University of
Karlsruhe
15 K2
41 K2
54 digital instruments
158 instruments
100 digital
JICA technical cooperation project :
“Reduction of seismic risk for buildings and structures
in Romania”
• Project signed in 2002, when 100 years of diplomatic relations between
Japan and Romania were celebrated
JICA Project in Romania is based on partnership of 3
institutions:
NCSRR, National Center for Seismic Risk Reduction
UTCB, Technical University of Civil Engineering Bucharest
INCERC, National Institute for Building Research, Bucharest
under the authority of:
MTCT, Ministry of Transports, Constructions and Tourism.
• Project duration: 5 yr
Total cost of the project
5.27 mill. USD
• Equipment cost 2.7 mill. USD:
- Soil testing laboratory
- Structure testing laboratory
- Seismic instrumentation network in Bucharest and Romania
(free field, borehole, buildings)
• 16 Romanian young students/engineer to be trained in Japan
• 34 Japanese short term and long term experts in Romania
Equipments for soil testing
and investigation
 Triaxial testing equipment
 Drilling equipment
 SPT/CPT testing equipment
Equipment for strong ground motion observation
Equipment delivered by JICA and installed together with two OYO technicians
and one Japanese expert:
- Altus K2 accelerometer (11)
- borehole sensors FBA-23DH (14+1)
- sensors EPISENSOR ES-T (9+1)
- ETNA accelerometer (5+1)
Seismic network
Free field
outside Bucharest
ETNA
6 sites
Borehole
Bucharest
K2
7 sites
3 sensors
(surface +
2 in borehole)
Building
Bucharest
K2
4 sites
Borehole seismic instrumentation
Surface and
borehole cables
Altus K2
accelerometer
Shallow
borehole
24÷30m
Borehole sensor
Borehole sensor
Deep
borehole
60÷153m
Free field
Bucharest - Location of borehole instrumented sites
Instrumented buildings in Bucharest
RISK U.E. Project
An advanced approach to earthquake
risk scenarios with applications to
different European towns
Flow charts of RISK UE Project (P. Mouroux)
Workpackage 1 of RISK-UE
European distinctive features, inventory database
and typology
Objective 1 - Distinctive features of European towns
• Town identity
• Population characteristics
• Urbanised area and elements at risk
• Impact of past earthquakes on elements at risk
• Strong motion data in the city and seismic hazard
• Geological, geophysical and geotechnical information
• Evolution of earthquake resistant design codes
• Earthquake risk management efforts
References
Objective 2 - Europe inventory database and typology
Classification of buildings occupancy
Code
Occupancy category
Importance & exposure
category
1
B
B1
1.1
1.2
1.3
1.4
1.5
1.6
B2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
B3
3.1
3.2
3.3
3.4
GENERAL BUILDING STOCK
Residential
Single family dwelling (house)
Multi family dwelling (apartment bldg.)
Low-rise (1-2)
Mid-rise (3-7)
High-rise (8+)
Institutional dormitory
Commercial
Supermarkets, Malls
Offices
Services
Hotels, Motels
Restaurants, Bars
Parking
Warehouse
Cultural
Museums
Theatres, Cinemas
Public event buildings
Stadiums
2
3
x
x1)
x1)
x2)
x2)
x
x
x
x
x2)
x
x
x
x
x
x
x
x3)
x2)
x2)
x2)
x
x
x
x
1) Buildings with capacity greater than 150 people
2) Buildings with capacity greater than 300 people or where more than 300 people
congregate in one area
Building typology matrix, BTM
Label
RC
Height description
Name
No. of
stories
Low-rise
Mid-rise
High-rise
Low-rise
Mid-rise
High-rise
1-3
4-7
8+
1-3
4-7
8+
h9
9 < h  21
h > 21
h9
9 < h  21
h > 21
Code level*
Height h, N L M H
m
Reinforced concrete structures
RC1
Concrete moment frames
RC2
Concrete shear walls
RC3
Concrete frames with unreinforced masonry
infill walls
Regularly infilled frames
Low-rise
Mid-rise
High-rise
1-3
4-7
8+
h9
9 < h  21
h > 21
Irregularly frames (i.e., irregular structural Low-rise
system, irregular infills, soft/weak story)
Mid-rise
High-rise
1-3
4-7
8+
Low-rise
Mid-rise
High-rise
Precast Concrete Tilt-Up Walls
Low-rise
Mid-rise
High-rise
Precast Concrete Frames with Concrete Low-rise
shear walls
Mid-rise
High-rise
1-3
4-7
8+
1-3
4-7
8+
1-3
4-7
8+
h9
9 < h  21
h > 21
h9
9 < h  21
h > 21
h9
9 < h  21
h > 21
h9
9 < h  21
h > 21
3.1
3.2
RC4
RC5
RC6
*Code level
Building type description
RC Dual systems (RC frames and walls)
N - no code;
L - low-code (designed with unique arbitrary base shear seismic coefficient);
M - moderate-code;
H - high-code (code comparable with Eurocode 8)
Comparative study for 7 towns
I. Population and Building exposure
Population and yearly GDP
Town
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
Inhabitants
1,503,451
79,456
2,011,305
333,075
342,738
1,133,183
1,048,151
Population density,
persons/km2
15,176
12,600
10,806
6,125
4,766
4,680
21,600
Population growth,
20th century*
1970
1990
1989
1971-1991 
1980
1985
1991
GDP/person
(approx.)
Euro
22,000
1,620
1,980
9,000-15,000
20,000
1,630
15,290
Population of the 7 towns
2,500,000
2,000,000
WP1. UTCB
1,500,000
Population
1,000,000
500,000
0
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
Population density in the 7 towns
25,000
20,000
Population
density,
persons/km2
WP1. UTCB
15,000
10,000
5,000
0
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
Number of buildings for the 7 towns
120,000
100,000
WP1. UTCB
80,000
Number of
buildings
60,000
40,000
20,000
NA
0
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
NA
Thessaloniki
Number of housing units for 7 towns
900,000
800,000
WP1. UTCB
700,000
600,000
Number of
housing units
500,000
400,000
300,000
200,000
100,000
0
Barcelona
Bitola
Bucharest Catania
Nice
Sofia
Thessaloniki
II. Earthquake hazard and earthquake instrumentation
10.5
10.5
9.5
LARGEST HISTORICAL
EVENT
20th CENTURY
9.5
WP1. UTCB
WP1. UTCB
8.5
8.5
7.5
7.5
6.5
6.5
5.5
5.5
4.5
4.5
NA
3.5
Barcelona
3.5
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
MSK local-intensity of largest experienced earthquake for the 7
towns
III. Vulnerability and typology of European buildings stock
Building stock age in the 7 towns versus
Seismic codes inter-benchmark periods
Town
Seismic codes inter-benchmark periods
Pre-code
Low-code
Moderate code
Barcelona
79%
21%
--
Bitola
48%
29%
23%
Bucharest
30%
30%
40%
Catania
92%
-
8%
Nice
75%
Sofia
Thessaloniki
25%
Data not available
20%
50%
30%
Buildings typology
Masonry buildings types for the 7 towns
Town
Masonry structures, M
1.1
Barcelona
Bitola
Bucharest
Catania
Nice
Sofia
Thessaloniki
1.2
1.3
2
3.1
3.2
3.3
Wood
3.4
4
5
1
World Bank project in Romania
Component A:
Strengthening of Disaster management capacity ~5%
Component B:
Earthquake Risk Reduction ~35%
Subcomponents:
•Strengthening of high priority buildings and lifelines
•Design & supervision
•Building code review and study of code enforcement
•Professional training in cost effective retrofitting
Components C D& E: Flood, Pollution & Project Management 60%
Implementation unit for Component B at
MTCT, Ministry of Transports, Construction and Tourism
Romanian Government has been approved the following list of
buildings to be retrofitted on April 7, 2004
In
Bucharest
Emergency bldg
12
Hospitals bldg
13
Educational bldg
6
Important public bldg
6
Essential facilities
Total
37
Type of buildings
In seismic counties
of Romania
18
9
6
14
47
Total
30
22
12
6
14
84
The buildings list is splitted in two lists: priority list and additional list.
Priority list of buildings contains 65 buildings i.e:
In
In seismic counties
Bucharest
of Romania
Emergency bldg
11
187
Hospitals bldg
12
7
Educational bldg
6
6
Important public bldg
6
Total
35
30
Type of buildings
Total
28
19
12
6
65
Distribution of buildings with occupancy
Public
12%
Educational
18%
Emergency
facilities
30%
Communication
26%
Emergency
facilities
39%
Public
4% Educational
11%
Hospitals
40%
Hospitals
20%
Bucharest
Other cities
Distribution of number of
buildings to be retrofitted
Distribution of cost for
buildings to be retrofitted
Other cities
33%
Bucharest
38%
Other cities
62%
Bucharest
67%
Distribution of buildings with number of stories
60
60
Bucharest
50
Number of buildings
Number of buildings
50
40
30
20
10
0
Other
cities
40
30
20
10
5
8
Number of stories
0
5
8
Number of stories
Distribution of buildings with floor area
15
15
Other
cities
10
30
00
>
30
00
25
00
250 500 1000 1500 2000 2500 3000
Total floor area, m²
20
00
0
15
00
>3
00
0
30
00
25
00
20
00
15
00
10
00
50
0
250 500 1000 1500 2000 2500 3000
Total floor area, m²
10
00
0
5
50
0
5
<2
50
Number of buildings
10
<2
50
Number of buildings
Bucharest
Distribution of buildings with year of construction
18
18
59%
14
14
12
12
10
56%
16
Number of buildings
41%
8
6
4
40%
10
8
6
4
4%
2
2
No code
...
P13-63 P100-78 P100-92
0
Year of constr.
Building code
1900 1940 1963 1978 1992
19
40
19
63
:P
13
-6
3
19
78
:P
10
078
19
92
:P
10
092
19
63
:P
13
-6
3
19
78
:P
10
078
19
92
:P
10
092
Building code
1900 1940 1963 1978 1992
19
40
<1
90
0
0
Year of constr.
<1
90
0
Number of buildings
16
No code
...
P13-63 P100-78 P100-92
Distribution of buildings with present seismic intensity
map
90
80
77
Number of buildings
70
60
50
40
30
20
10
0
9
1
VII
VIII
IX
Seismic intensity
MSK
World Bank report
“Preventable Losses: Saving Lives and Property through Hazard
Risk Management”
Strategic Framework for reducing the Social and Economic Impact of
Earthquake, Flood and Landslide Hazards in the Europe and Central Asia
Region
Draft, May 2004
• Romania is regarded as one the most seismically active countries in
Europe
• Bucharest is one of the 10 most vulnerable cities in the world.
Recommendations for Romania:
• Upgrade the legal framework for hazard specific management;
• Review the existing buildings code for the retrofitting of vulnerable
buildings;
• Conduct a comprehensive public awareness campaign for the
earthquake risk;
• Invest in hazard mitigation activities in order to reduce the risks
caused by earthquakes;
• Develop financing strategy for catastrophic events.