CASITA Earthquake Risk Assessment of Ahmedabad City School of Planning, Center for Environmental Planning and Technology (CEPT) Ajay K Katuri, Urban Planner Prof. Madhu Bharti, Urban Planner Mr. Anoop Karanth, Environmental Planner
This work seeks to provide a forecast of the types of losses that the City of Ahmedabad could suffer after an earthquake
The development of the earthquake scenario and consequences are intended for the purpose of emergency planning and preparedness only. The study is very much based on the hypothetical considerations: • the earthquake occurs • the damage potential is based on the output of the loss estimation model and on experiences from historical earthquakes 2
INTRODUCTION Urban seismic risk is rapidly increasing in developing countries where a number of cities are growing. ►
Risk is typically defined by two components: - a hazard (the earthquake) - the assets involved
Identification of problems and vulnerable elements is of a prime concern in handling of disasters. The primary purpose of any effort in disaster mitigation is to simplify identification of the physical dimensions of risk reduction rather than disaster prevention. It is therefore “risk management” that is being dealt with rather than disaster prevention. There is a low probability of recurrence of earthquakes HOWEVER the Ahmedabad city is under high risk because of: - poor geological hazard assessment and associated vulnerability - most structures are not seismically designed
►
3
Aim The aim of the study is to carry out seismic risk assessment of Ahmedabad and to assist in formulating a Risk Management Plan. The following aspects is looked upon as part of this study: • Detailed geological hazard assessment • Damage assessment results of 26th January earthquake • Seismic considerations, Planning considerations and Scenario Consequences for existing urban structures, city infrastructure, emergency activities such as life saving, firefighting, emergency transportation, etc. The overall aim of the risk mitigation plan is to assist city decision makers on decisions about present infrastructure, existing elements and future development.
Objective The objective of the study is; • to develop an earthquake damage scenario which describes the consequences of a possible earthquake
4
RADIUS - A Tool for Earthquake Damage Estimation The United Nations General Assembly designated the 1990s as the “International Decade for Natural Disaster Reduction (IDNDR)” to reduce loss of life, property damage, and social and economic disruption caused by natural disasters. 9 The IDNDR Secretariat launched the RADIUS (Risk Assessment Tools for Diagnosis of Urban Areas against Seismic Disasters) initiative in 1996. 9 The tool is a computer programme running on Excel 97, The user needs to input the following information: • Shape of target region by meshes • Total population and distribution • Total buildings, building types and their distribution • Ground condition (soil type) • Total numbers of lifeline facilities • Choice of scenario earthquake and its parameters
9 The programme then validates the input data and performs analysis. Output from the analysis includes: • • • • •
Seismic (ground shaking) intensity, such as PGA and MMI Intensity Building damage Lifeline damage Casualties, such as number of deaths and injuries Summary tables and thematic maps showing the result 5
Process of Damage Estimation Scenario Earthquake
Earthquake Hazard
Earthquake Disaster Reduction Planning Damage Estimation
§ §
Demographic data,
Ground Motion
§
Bldg & Lifeline Inventory,
Preparedness Emergency Planning Recovery
Vulnerabilities
INPUT
+
INVENTORIES
=
OUTPUTS
R s.
Data 6
Soil Condition: Classification or zoning of ground conditions is important in the earthquake damage estimation process because ground conditions directly affect seismic amplification of ground shaking. When classifying ground conditions, vast amount of soil data are required. This Tool adopts a simple classification, which divides the ground into 4 classes with corresponding amplification factors.
Amplification Factor
Surface Ground Amplification 1.5 1.0 0.5 0.0 Hard Rock
Soft Rock
Medium Soil
Soft Soil
Rock/Soil Type Surface ground amplification for various soil type 7
Building Damage: This Tool uses the following 10 classification categories, adopted by sample Latin American countries. This classification was determined based on the building material, construction type, applied code, usage and number of stories, etc. B u ild in g C la s s e s E x p la n a tio n Inform al c ons truc tion - m ain ly s lum s , row h ous ing etc . m ad e from u nfired b ric ks , m u d m ortar, loos ely tied w alls an d roofs .
R E S 2 ---
U R M -R C c om p os ite c ons truc tion - s u b-s tand ard c ons truc tion, not c om plyin g w ith the loc al c ode p rovis ion s . H eigh t u p to 3 s tories . U R M is U n -R einforc ed M as on ry
R E S 3 ---
an d R C is R ein forc ed C onc rete b uild ing U R M -R C c om p os ite c ons truc tion - old, d eteriorated c on s tru c tion, not c om plying w ith the lates t c od e provis ions . H eig ht 4 - 6 s tories .
R E S 4 ---
E ng in eered R C c ons tru c tion - n ew ly c ons truc ted m u lti-s toried bu ild in gs , for res iden tial and
Building Damage Curve
100 80
Damage Rate (%)
R E S 1 ---
60 40 20
c om m erc ial p urpos es . E D U1 ---
S c hool b uilding s , u p to 2 s tories .
E D U2 ---
u s u ally perc en tag e s h ould b e very s m all S c hool b uilding s , g reater th an 2 s tories .
M E D 1 ---
u s u ally perc en tag e s h ould b e very s m all L ow to m ediu m ris e hos p itals
M E D 2 ---
u s u ally perc en tag e s h ould b e very s m all H ig h ris e h os pitals
C O M ----
u s u ally perc en tag e s h ould b e very s m all S hop ping C en ters
IND -----
Ind us trial fac ilities , both low and h ig h ris k
0 4
5
6
7
8
9
10
11
12
MMI RES1 MED1
RES2 MED2
RES3 COM
RES4 IND
EDU1
EDU2
Building Damage Curve (Damage Rate in % to MMI) 8
Lifeline Damage: Lifeline facilities include water, sewage, electric power, gas supplies and transportation networks, namely roads and bridges, etc Vulnerability curves for each lifeline are determined as the function of acceleration/MMI based on observed damage to lifeline facilities in past sample earthquakes. Lifeline Damage Curve 100
Damage Rate (%)
80 60 40 20 0 4
Lifeline Damage Curve (Damage Rate in % to MMI)
5 Road1 Tunnels Water1 Reservoir1
6
7
8 9 MMI Road2 Electric1 Water2 Reservoir2
10
11
12
Bridge Electric2 Water3 Gasoline 9
Part 1
THE SCENARIO EARTHQUAKE A. GEOLOGY AND SEISMOLOGY B. SCENARIO EARTHQUAKE DEVELOPMENT
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A. GEOLOGY AND SEISMOLOGY
Seismic Hazard and Vulnerability
Figure indicates the location, year and number of fatalities (in parenthesis) for earthquakes in India in the past 200 years (Bilham and Gaur, 2000).
a More than 100,000 fatalities from earthquakes have occurred on the Indian Plate in the past two centuries. b The rate of occurrence of fatal earthquakes in the past two decades is more than double its mean value in the past two centuries
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12
Earthquake Hazard in Gujarat
MMI IX 19% MMI VIII 14% MMI VII 66%
Seismic Zoning Map of India
Earthquake Zone Area Hazard Map of Gujarat
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Seismic Hazard Zonation
Figure Seismic Hazard Map India. Figure shows the peak ground acceleration (PGA) that a site can expect during the next 50 years with 10 percent probability (Source: www.geology.about.com) 14
Seismicity in India, Relative depths of occurrence 15
B. SCENARIO EARTHQUAKE DEVELOPMENT Scenario Earthquake Earthquake Scenarios describe the expected ground motions and effects of specific hypothetical large earthquakes. In planning and coordinating emergency response, utilities, emergency responders, and other agencies are best served by conducting training exercises based on realistic earthquake situations, ones that they are most likely to face. The potential shaking effects is the main benefit of the earthquake scenario for planning and preparedness purposes.
Past Earthquake Damage in Ahmedabad Several high-rise buildings collapsed in Ahmedabad killing close to 800 persons during the last Bhuj Earthquake. The city on the eastern side of the river has mostly 3 or 4 storey brick buildings with load bearing walls which virtually received no damage, except for cracks in walls, even though the building and population densities are high. The western side of the city has mostly 5 (ground + four) and a large number of ten storey buildings, whereas in the south-east most of the buildings are 5 storey. Several thousand buildings were damaged in the town to various degrees.
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The relation of damage pattern to location of paleochannels of the Sabarmati river can be seen in the IRS LISS III imagery of the city. •The paleochannel in the picture is seen as a small faint white loop, 4 – 5km west of the present river course. Some of the collapse buildings in the western part of the town lie within the zone bound by the past and present courses of the river. •Thus poor soil condition, presence of water and Basin Edge effect may have contributed to more damage in their proximity. •Inference: geological conditions, and site amplification, damage.
Satellite image (IRS IC LISS – III) of Ahmedabad (January 1996) showing palaeochannel, lakes and damaged area during 26th January Bhuj earthquake, Source: ISRO 17
Pattern of collapsed buildings in Ahmedabad, showing that they lie in a linear pattern and in a group of clusters. The five biggest clusters (consisting of 5 to 8 buildings) are identified by a circle. Most of the collapsed buildings lie in three bands, which are about 200m and 1.2 km in width.
(Source: Damage pattern due to January 2001 Bhuj earthquake, India by N.Bhandari and B.K.Sharma, Physical Research Laboratory, Ahmedabad) 18
Geology of Ahmedabad • Ahmedabad city is located on 3km to 4km thick sandstone, clay and alluvium soil of Sabarmati river within the Cambay Graben. • The Deccan basement, generally found in the adjacent Cambay basin at 4 to 5km depth is missing at Ahmedabad and the hardrock basement of granite rocks occur at the depth of about 7-8km. • The upper 200 – 300m below the Ahmedabad city is mostly alluvium, formed by the meandering Sabarmati river in the past
Deep section along Mehmedabad – Nadiad region (modified after, Kaila et al., 1981)
Cross section of a Sedimentary column at Ahmedabad – Paldi (after Bhandari et al., 1986) 19
Location of Ahmedabad in the Cambay rift zone (Source: Seismotectonics Atlas, Geological Survey of India, 2000).
Structural Map of Ahmedabad oil field and vicinity showing two faults running east and west of Ahmedabad trending NNW to SSE. (Source Kumar et al 2000) 20
Soil Conditions Soil depth and texture map of Ahmedabad and its environs
Source: Revised draft development plan of AUDA – 2011 AD. Part – 1 Surveys, Studies and Analysis.
Based on this, the type of soil for the city is considered to be of “Soft Soil” type. Corresponding to soft alluvial soil, reclaimed land and landfill etc., the soil is assigned with a amplification factor of 1.3. 21
Choosing an Appropriate Earthquake Scenario Scenario 1
Figure showing the Scenario Earthquake Epicenter at the junction of Marginal Faults intersection, one of Cambay Graben and the other of Narmada Graben. Hypocenter of Scenario Earthquake falls in the city of Bharuch which is about 150kms from Ahmedabad. 22
Scenario 2
Figure showing the Scenario Earthquake Epicenter on the Marginal Faults defining the Cambay Graben. Epicenter of Scenario Earthquake falls 30 kms North West of Ahmedabad.
Case 1 2 3
Location Bharuch Bhuj 26 th Jan Earthquake* Ahmedabad
Epicentre Distance (in kms) 150 300 300 30
Magnitude
Depth (in km)
Time __:__hrs
Casualty in the city
7 7.7 7.7 7
12 22 22 12
0:00 8:46 8:46 0:00
3766 0 746 21502
* realistic death figure in the city of Ahmedabad during 26th January Bhuj earthquake. Also note the difference in the figure of death when the simulation was done taking the 23 same parameters.
Part 2 ENERAL CONSEQUENCES OF THE G SCENARIO EARTHQUAKE
A. PROFILE OF THE STUDY AREA B. INDRODUCTION TO THE CONSEQUENCES C. ESTIMATION OF ELP D. GROUND MOTION E. MASS CASUALTY SIMULATION F. BUILDINGS AND STRUCTURES G. EMERGENCY FACILITIES AND RESPONSE H. TRANSPORTATION SYSTEMS I. COMMUNICATIONS J. LIFELINE UTILITIES
Sub topics looked in terms of General Characteristics, Seismic Considerations,
Planning Considerations and Scenario Consequences
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A. PROFILE OF THE STUDY AREA CHARADA
A MJA
NAROLA
City Area: 190.84 sq.km (AMC limits)
KOTHA
AMRAPUR
NADRA NAVA
CHANDISAN
Geology: Falls in alluvial tract and comprises mostly quaternary thick alluvial and blown sand Hydrogeomorphology: The study area falls under Alluvial Plain (reclaimed) type. Comprises vast alluvial tract supporting the main urban population Paleochannel: Probable presence of palaeochannel of a past tributary of the Sabarmati river Soil: Built-up land. BA RMUVD
Surface Water Bodies: River Sabarmati and several important lakes and talavadis (many are backfilled)
UMEDPURA GO KADPUR
NANI TIBLI PAHADI JALAMPUR G ODASAR RATANPUR
AK ALA CHHA
Geology Settings: Lies in two Marginal Faults and also on the intersection of two Minor Lineaments
SUND HA SA YALA
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North Zone Cantonment
Central Zone West Zone East Zone
South Zone
Sabarmati River
Figure Zone location in AMC area
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Population: 35,15,361 (AMC) Density: 18,421(persons/sq.km) Municipal Infrastructure: • Health Facilities Total number of beds – 4782 beds • Fire Department 10 fire stations (avg. 35 persons per fire station) • Education Institutions Total numbers – 1727 • Transportation Road, Railway and Air Transport • Water Supply Network – 2543 km, Distribution Stations – 78, Terminal Reservoirs and ESR – 41 • Sewerage Network – 1345 km, Pumping Stations – 38, STP – 2 (and two under construction)
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• Communication Telephone Exchange Buildings – 42 Transmission Towers – 35 • Electricity Number of Electrical Sub station – 13 Major Electrical Transmission Tower – 492
Housing Total Housing Stock 10.50 lakhs
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Study Area The area is divided into 58 blocks and each block consists of 40 cells of 250m X 250m each Total area: 118.5 sq.km Total cells: 1895 cells of 250m X 250m each
City Map of Ahmedabad Source: SETU City Map, SETU Publications 1988, Map prepared by SETU CYBERTECH PVT Ltd. 29
Figure Division of the SETU Map into 1895 cells of 250m X 250m each
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Soil Type Distribution Map as an input map of RADIUS ## ## ## ## ## ## ## ## ## ## ## ## ## ## ## ## ##
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C o l o r
V a l u e R a n g e f o r 0 1 2 3 4
D e s c r i p t i o n U n k n o H a r d R S o f t R M e d i u m S o f t S
w n o c k o c k S o i l o i l
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Scenario Consequences Mesh weight distribution map
Color
Value Range for mesh
Mesh Weight
0
None
1
Low
2
Average
3
High
4
Very High
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Figure shows the probable intensity distribution for all the three magnitudes M6, M6.5 and M7
Color ID
M 6*
M 6.5
M7
Range
Range
Range
From
To
From
To
From
To
6.5
6.7
7.1
7.2
7.6
7.7
6.7
6.8
7.2
7.3
7.7
7.8
6.8
6.9
7.3
7.4
7.8
7.9
6.9
7.0
7.4
7.6
7.9
8.0
Avg MMI
6.79
7.32
7.78
Avg PGA
0.11g
0.16g
0.22g
* Many of the results for M6 of the scenario earthquake show similar results when compared to the last Bhuj Earthquake.
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E. MASS CASUALTY SIMULATION Estimated number of people killed and injured in Ahmedabad city
Total Day Population Total Night Population Magnitude Time of occurrence
Total death population
Total severely injured
M6
1251
2989
M 6.5 M7
00:00 hrs M6 12:00 hrs 00:00 hrs M 6.5 12:00 hrs 00:00 hrs M7 12:00 hrs
923 7233
2608 17475
4775 21502
12707 51795
13679
36228
3566829 3550000 Total injured
Total moderately injured 44638 47627 41037 43644 114805 132280 91888 104595 204587 256382 149050 185279
Casualty estimation in terms of percentage
Magnitude M6 (00:00hrs) M6 (12:00hrs) M6.5 (00:00hrs) M6.5 (12:00hrs) M7 (00:00hrs) M7 (12:00hrs)
Total population 3550000 3566829 3550000 3566289 3550000 3566829
Total death % of total population population 1251 0.035 923 0.026 7233 0.20 4775 0.13 21502 0.61 13679 0.38
Total injured
% of total population 47627 1.34 43644 1.23 132280 3.73 104595 2.9 256382 7.22 34 185279 5.22
Casualty (death) distribution (Magnitude M 7, Time of occurrence 00:00hrs) Total death: 21502 (0.61% of total population)
Color ID
Range From
To
0
9
9
19
19
28
28
38
35
Casualty (injured) distribution. (Magnitude M 7, Time of occurrence 00:00hrs) Total injured: 256382 (7.22% of total population)
Color ID
Range From
To
0
144
144
287
287
431
431
574
36
F. BUILDINGS & STRUCTURES BUILDINGS Building vulnerability is critical to earthquake risk. Collapsed buildings caused about three quarters of all earthquake fatalities during the 20th century. The risks associated along with it are both structural and nonstructural risks. The effects of an earthquake on buildings and structures depend on many variables, including: • Size of the earthquake • Depth of the earthquake • Geologic and soil characteristics of the site • Severity and duration of ground shaking • Code provisions used in the buildings design • Structural System failure • Building construction type, configuration and size • Quality of construction • Proper building maintenance
Reinforced concrete frame with unreinforced masonry infills is the most common structural system for RC buildings in Ahmedabad (View of Ahmedabad 2 km to the Southwest of the airport).
37
Building blocks – urban house in Ahmedabad
Building blocks - Urban House in Ahmedabad
Category
Details
Engineering Classification
Category A
buildings made of fieldstones, unun-burnt bricks and clay structures
Non Engineered
24%
Category B
brick buildings fall under this category.
Less Engineered
71%
Category C
consists of reinforced concrete and wellwellconstructed wooden buildings
Engineered
4%
Category X
includes buildings constructed materials like grass and thatch
Non Engineered
1%
with
Source: : Towards a culture of Safer Building Practices — by Rajib Shaw, United Nations Centre for Regional Development, Kobe-Japan
38
Structural System Deficiency
Example of a soft-story apartment building (Photograph by Goel) Example of overhang at upper floors in residential construction (Photograph by Goel)
Figure Floating columns in upper stories along perimeter of buildings to optimize FSI requirements, lead to irregularities in load transfer paths in elevation (Source: Reinforced Concrete Structures, Earthquake Spectra 2001 Bhuj, India Earthquake Reconnaissance Report, Supplement A To Volume 18, July 2002)
39
Structural Damage
Shearing of unsupported corner column, Mehta Chambers
Crushing and spalling of concrete close to the beam bottom, Tagore Park Society.
No lateral load force transfer mechanism to the core, Punjal Apartments
Poor quality construction material, Neelima Park Apartments
40
Damaged multistory building (Manasi complex) in Ahmedabad (soft story ground floor with rigid beams and weak columns).
Building with unsymmetrical plan due to infill walls, Apollo Apartments
41
Half of the building pulled away from the elevator core that formed the shear core of the building
Part of the building fell on the neighboring building indicating presence of torsional motions (Photograph by Goel)
Poor quality of concrete (Photograph by Goel)
42
Building stock in terms of percentage for the city of Ahmedabad (RADIUS default building type) B uilding Classes E xplanation R ES1---
Inform al construction - m ainly slum s, row housing etc. m ade from unfired bricks, mud mortar, loosely tied walls and roofs.
R ES2---
U RM -RC com posite construction - sub-s tandard construction, not com plying with the local code provisions. Height up to 3 stories. U RM is Un-Reinforced M asonry
R ES3---
Res2 37.75%
Res1 20.80%
and RC is R einforced Conc rete building U RM -RC com posite construction - old, deteriorated construction, not com plying with the latest code provisions. Height 4 - 6 stories.
R ES4---
E ngineered RC cons truction - newly constructed m ulti-storied buildings, for residential and comm ercial purposes.
E DU1---
S chool buildings, up to 2 stories.
E DU2---
usually percentage should be very sm all S chool buildings, greater than 2 stories.
M ED1---
usually percentage should be very sm all Low to medium ris e hospitals
M ED2---
usually percentage should be very sm all H igh rise hospitals
C OM ----
usually percentage should be very sm all S hopping Centers
IND -----
Industrial fac ilities, both low and high risk
IND 7.99% COM 6.28% MED2 0.32%
Res3 20.76% MED1 0.20%
EDU2 1.14%
EDU1 0.65%
Res4 4.11%
43
Building Distribution in Map
Manual Range
Color ID 0
100
100
200
200
300
300
400
44
Damage building distribution for magnitude M 7
Range
Color ID
DAMAGE SUMMARY
M6
M 6.5
M7
Total number of damaged buildings
500000
39333
76914
120748
Percentage damage of buildings
-
7.86%
15.38%
24.15%
From
To
0
31
31
61
61
92
92
122
45
Damage count of individual type for magnitudes of M6, M6.5 and M7
35
Percentage dam age
30 25 20 15 10 5 0 RES1
RES2
RES3
RES4
EDU1
EDU2
MED1
MED2
COM
IND
Building Type
M6
M 6.5
M7 46
M6
M 6.5
M7
damage area
Location of buildings in groups where there is possibility of maximum damage to buildings from the scenario earthquake. 47
Overlap showing the damage buildings for magnitude M7 with the existing land use
48
49
Existing Education Institutions Number of School
Type of School
Number Students
of
Municipal Primary
563
2,06,949
Private Primary
715
6,51,065
5
2,005
Private Secondary
226
54,218
Private Higher Secondary
210
1,68,115
8
1,780
Individual damage count for M6
Individual damage count for M6.5
Individual damage count for M7
Municipal Secondary
Others
Scenario Consequences – School Buildings
Estimated percentage of school buildings damaged for each category Category
Total building count
EDU1
3271
4.40%
8.32%
12.96%
EDU2
5699
8.48%
14.88%
21.85% 50
Existing Hospital systems and Medical Facilities Medical Facilities in the city Medical Facilities by AMC
Medical Facilities by others
Type of Hospital
Nos.
Type of Hospital
Nos.
General Hospital
3
Civil hospital
1
Ophthalmic Hospital
1
Bapunagar Gen. (ESSI)
1
T.B.Hospital
1
Naroda TB Hospital (ESSI)
1
Infectious Disease Hospital
1
Urban Health Centre
36
Referral Hospital
5
Pathological Laboratory
5
Maternity Homes
8
Aanganwadis
Dental clinics
3
Super Speciality Centres
Dispensaries
20
Private registered Nursing homes
Mobile Dispensaries
2
222 2 1317
Total number of beds: 4782 nos
51
Scenario Consequences – Medical Facilities
Estimated percentage of hospital buildings damaged for each category Category
Total building count
Individual damage count for M6
Individual damage count for M6.5
Individual damage count for M7
MED1
1002
7.09%
11.58%
17.17%
MED2
1580
8.54%
14.24%
21.27%
Estimated number of people killed and injured in Ahmedabad city Total Day Population
3566829
Total Night Population
3550000
Magnitude
Time of occurrence
Total death population
Total injured
M6
00:00 hrs
1251
2989
M6 M 6.5
12:00 hrs 00:00 hrs
M 6.5 M7
7233 12:00 hrs
00:00 hrs M7
923 4775
Total injured
44638
47627 41037
114805 12707
51795 13679
Total moderately injured
2608 17475
21502 12:00 hrs
severely
132280 91888
204587 36228
43644 104595 256382
149050
185279
Available beds after an occurrence of earthquake is probably (say) 1700nos out of 4782 nos.
52
Medical Care Capability and Emergency Response Contribution
GESI result for Ahm edabad City's Risk Distribution 22.6% Building Collapse
53.2%
Search & Rescue Problems Emergency Response Problems
23.4% 0.8%
Medical Care Problems
53
Scenario Consequences – Transport System
Estimated road network damage Lifeline (Road 1) Length of local roads
Total count
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
20.3
1.6
M 6.5
7.32
0.16
38.8
3.1
M7
7.78
0.22
59.2
4.7
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
0.2
3.5
M 6.5
7.32
0.16
0.4
6.0
M7
7.78
0.22
0.6
8.3
1272 km
Estimated transportation bridge damage Lifeline (Bridges) Number of Major Transportation Bridge (Road and Rail)
Total count
7
54
Scenario Consequences – Telephone Communication System
Damage estimation for transmission towers Lifeline (Electric1) Number of Major Telecommunication Transmission Tower
Total count
35
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
0.38
1.1
M 6.5
7.32
0.16
0.62
1.8
M7
7.78
0.22
0.82
2.4
Damage estimation for telephone exchange substations Lifeline (Electric 2) Number of TeleTelecommunication Substation
Total count
42
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
3.81
9.0
M 6.5
7.32
0.16
5.65
13.4
M7
7.78
0.22
7.63
18.2
55
Scenario Consequences – Electricity Transmission System Damage estimation Lifeline (Electric1) Number of Major Electrical Transmission Tower
Total count 492
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
5.41
1.1
M 6.5
7.32
0.16
8.78
1.8
M7
7.78
0.22
11.57
2.4
Damage estimation for electrical substations Lifeline (Electric 2) Number of Electrical Substation
Total count 13
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
1.18
9.0
M 6.5
7.32
0.16
1.74
13.4
M7
7.78
0.22
2.36
18.2
56
Scenario Consequences – Water Distribution System
Damage estimation of water systems Lifeline (Water 1) Length of Major Water Distribution Line Number of Water Pumping Stations
Number of Water Treatment Plant
Number of Storage Reservoirs
Number of Elevated Storage Tanks
Total count 2543km
23 nos
2 nos
105 nos
41 nos
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
14.08
0.6
M 6.5
7.32
0.16
28.23
1.1
M7
7.78
0.22
43.70
1.7
M6
6.79
0.11
1.17
5.1
M 6.5
7.32
0.16
1.77
7.7
M7
7.78
0.22
2.41
10.5
M6
6.79
0.11
0.058
2.9
M 6.5
7.32
0.16
0.088
4.4
M7
7.78
0.22
0.12
6.0
M6
6.79
0.11
3.67
3.5
M 6.5
7.32
0.16
5.14
4.9
M7
7.78
0.22
6.19
5.9
M6
6.79
0.11
0.49
1.2
M 6.5
7.32
0.16
1.02
2.5
M7
7.78
0.22
1.59
3.9 57
Scenario Consequences – Sewerage System
Damage estimation of sewage systems Lifeline (Water 2) Length of Major Sewage Trunk Distribution Line Number of Sewage Pumping Stations
Number of Sewage Treatment Plant
Total count 1345km
38 nos
4 nos
Magnitude
Average MMI
Average PGA (g)
Damage Number
Damage Ratio (%)
M6
6.79
0.11
8.07
0.6
M 6.5
7.32
0.16
14.79
1.1
M7
7.78
0.22
22.86
1.7
M6
6.79
0.11
1.94
5.1
M 6.5
7.32
0.16
2.92
7.7
M7
7.78
0.22
3.99
10.5
M6
6.79
0.11
0.11
2.9
M 6.5
7.32
0.16
0.17
4.4
M7
7.78
0.22
0.24
6.0
58
Scenario Consequences – Petroleum Stations
Damage estimation of petroleum stations Lifeline (Gasoline) Number of Gasoline Stations
Total count 45nos
Magnitude
Average MMI
Average PGA (g)
M6
6.79
0.11
2.9
6.5
M 6.5
7.32
0.16
5.3
11.8
M7
7.78
0.22
7.8
17.4
Damage Number
Damage Ratio (%)
59
Proposed course Outline
• Name of the course: Risk Management for Urban Development • Status: Elective • Duration: 14 weeks • Credits: 4 (2hr/week) • Mode of evaluation: Assignments, Case studies, End exam
60
Target Schools and Programs Center for Environmental Planning and Technology (CEPT) • School of Planning • Masters in Urban and Regional Planning, Environmental Planning and Housing (45 students) • School of Building Science and Technology • Construction Project and Management (Masters) (10 students) • Structural Design (Masters) (10 students) Center for Excellence for Environment and Sustainable Development (CEED) • Urban Management (PG Diploma) (15 students)
61
Proposed course Outline • Session 1- 4 Introduction to Hazards and Related Risks • Definition to Hazards • Types and extent and vulnerability
• Session 5- 8 Vulnerability Assessment • RADIUS, ILWIS/ArcGIS
62
Proposed course Outline • Session 9- 13 Geo-Information systems for Hazard Managements • Spatial databases Management Systems • Relational Database Management Systems • ILWIS, ArcView, ArcGIS, ERDAS
• Session 14- 19 Damage and Loss Assessment • Existing Damage and Loss Assessment Mechanisms • HAZUS, ECLAC, other models to be developed
63
Proposed course Outline • Session 20- 25 Risk Management and policy contribution • Safe Practices and Policies • Standard Building Codes and practices
64
Thank you
65
