probabilistic seismic risk assessment for the metropolitan

Probabilistic Seismic Risk Assessment for the Metropolitan

Region of San Salvador (AMSS): Educational, Public Health and

Governmental Agencies

Cape Town, South Africa, July 2012

Ministry of the Environment and Natural Resources - Government of El Salvador

Seismic Risk Assessment for the AMSS

Exposure

Vulnerability

Risk Assessment

HAZARD SCENARIO

RISK DISASTER

Seismic Hazard

Site Effects

Exposure Data & Building

Characteristics

Expected EQ

Performance

Prospective Management

Reactive Management

Financial

Protection

Corrective Management

Risk

Management

1050

100 150

400

125 8

1500

944

315 No

. O

f D

eath

s

Human and

Economic Losses

0

1

0 1000 2000

Dam

age (

%)

Intensity (gal)

Regional Seismicity & Attenuation


SEISMIC HAZARD MAP – NATIONAL LEVEL

On the basis of the Project RESIS II

MICROZONATION

(PROXI)

SOURCE

Seismogenic source characteristics, Magnitude

ATTENUATION

Attenuation of intensity over distance

SITE EFFECTS

Amplitude and frequency content modification due to local site conditions

Seismic Hazard Assessment

Seismic ground motion at a site depends on


Seismic hazard is calculated

considering the sum of the

effects of all seismic

sources and the distance

between each source and

the site, for different

spectral ordinates

Seismic Hazard – National Level

Definition and characterization of the seismic sources (RESIS II)

Seismicity parameters for each seismic source (RESIS II)

Attenuation models (intensity at the site based on magnitude and distance)


Seismic hazard map does not take into account the effects of the local

site conditions (site classification “rock”)

0

50

100

150

200

250

300

350

0 0.5 1 1.5 2

Sa

(g

al)

Periodo

ZH06 M6.6

CLI94 M6.6

PA 13.02.2001

Earthquake 13.02.2001 (PA)


TBJ Deposits, Centro de Gobierno, S.S.

Elastic Response Spectra from the 1966, 1989 and 1994 Seismic

Codes compared to the Elastic Response Spectra of the 1986

Earthquake in the East-West Direction (5% Damping)

Amplification due to Site Effects


Amplification due to Site Effects

MICROZONATION MAP PROXI

DYNAMIC RESPONSE OF SOIL DEPOSITS (ELASTIC)

Am

pli

fica

tion

ZONE II

ZONE V


FIRST STEP: EDUCATION, PUBLIC HEALTH AND GOVERNMENT AGENCIES

Exposure Data Gathering

0

500

1000

Gobierno Salud

Educación

18 42

197

19 42

987

Exposure Data Gathering for prioritized educational, public health and governmental

institutions: geographical location, population, replacement cost, and the building

characteristics considered to be strongly related to the structures capacity to resist

earthquake loads (1550 buildings in 257 institutions)

Government

148 (9%)

Healthcare

352 (23%)

Education

1050 (68%)

Individual Buildings

Institutions

Government Public Health

Education

Total (AMSS) Analyzed


Basic Information:

Population (morning, evening, night)

Replacement Cost

Main Vulnerability Factors that Influence

Earthquake Damage

Main vulnerability factors

Structural System

Level of Earthquake Resistant Design:

Construction Year (Seismic Design Code)

Fundamental Period of the Building: Height

Secondary Vulnerability Factors

Damage during previous EQ

Short-Column Effect

Structural Torsional Irregularity

Deficiencies Soft/Weak Story Effect

Flat-slab /plate Structures

Etc.


Reinforced

Masonry

55% Others

18%

RC Frames

w/ infills

18%

RC Frames

9%



http://localhost/Vulnerabilidad/consulta/



Lack of planning and haphazard growth

Mixture of construction materials

with different seismic performance

(lack of continuity and homogeneity)

– Structural Deficiencies

Difficulties in exposure data

gathering – extraordinary amount of

buildings per institution

1 Institution- 59 different buildings (71 total) Precarious Systems (3.7%)

http://192.168.1.68/vulnerabilidad/fotografias/E20504/E20504-02-2/Baja calidad de Materiales 021.jpg


Analytical Models

Experimental data (Taishin)

Vulnerability Assessment

Lower

Vulnerability

Definition of Vulnerability Curves

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 500 1000 1500 2000 2500

Dam

age

(fr

acti

on

f r

ep

lacem

en

t co

st)

Spectral Acceleration (gal)

PMR-2CM(2)

M2

MCSJ-2CM (2)

DUAL-2

MCCJ-2CM (2)

MACA-2CM

MASA-2CM(2)

0

500

1000

1500

2000

2500

0 0.5 1 1.5 2 2.5 3 3.5 4

0

100

200

300

400

500

600

0 0.5 1 1.5 2 2.5 3 3.5 4

0

500

1000

1500

2000

0 0.5 1 1.5 2 2.5 3 3.5 4

0

500

1000

1500

0 0.5 1 1.5 2 2.5 3 3.5 4

0

200

400

600

800

1000

0 0.5 1 1.5 2 2.5 3 3.5 4

0

200

400

600

800

1000

0 0.5 1 1.5 2 2.5 3 3.5 4

0

500

1000

1500

0 0.5 1 1.5 2 2.5 3 3.5 4

Vulnerability Curves Analytical Models

Calibration - observed damage


0

50

100

150

200

250

Pérdida

Pérdida Acumulada

Escenarios Sísmicos (T5000años)

Pér

did

a (1

06 U

S$)

0

25

50

75

100

Pér

did

a A

cum

ula

da (

10

9 U

S$)

Probabilistic Risk Assessment

Considering the contribution of all seismic scenarios and their

probability of occurrence, an annualized los on the order of USD$14.7

Millions, was estimated to cover only 257 institutions, 5.78% of the total

exposed value.

Losses Cumulative Losses

Earthquake Scenarios

Cum

ula

tive

Loss

es

Loss

es


Seismic Risk Assessment for the RMSS

Probabilistic modeling of Seismic Risk Scenarios for the AMSS, Educational, Public Health and

Governmental Institutions

LEGEND

Probabilistic Analysis

Annualized loss

(% Exposed Amount)

Probabilistic modeling of Seismic Risk Scenarios for the AMSS, Educational, Public Health and

Governmental Institutions

LEGEND

Probabilistic Analysis

Annualized loss

(1000 US)


Risk Management

Corrective

Management

Reactive

Management

Financial

Protection

Risk

Assessment

Prospective

Management

Risk Assessment to provide decision-making tools for risk reduction

Identification Detailed analyses for

critical possible reinforcing/

infrastructure retrofitting measures

Risk

Assessment

Corrective

Measures

Individual

Components

Hazard & Site Conditions Detailed

Construction practices Investigations

Vulnerability of Bldg. Types (eg. Microzonation)

Building Codes

Land-use Plans

Emergency

Preparedness

and Response

Risk Scenarios Response Plans

Attenuation & Site Effects Shakemaps & Real

Existing Infrastructure Time Loss Estimation

Risk &

Individual

Components

DISASTER PREVENTION DISASTER PREPAREDNESS


Risk Reduction Measures

Measure Ongoing Research Future Work Needed

HA

ZA

RD

AN

D R

ISK

AS

SE

SS

ME

NT

Instrumenta-

tion for Data

generation.

Hazard and

Risk

Assessment

Studies

Improvement of the Seismic

Network (PNRR, 2012; JICA, 2014)

Site effect investigation (AMSS)

PROXI for evaluation of seismic site

conditions and amplifications at a

national level (PGA)

Strong motion data base,

consultation and graphic

representation of SM parameters

Complete seismic risk assessment for

remaining AMSS educational institutions

Risk assessment of major cities.

Instrumentation of Important Buildings

(vulnerability assessment and structural

health monitoring)

Constant updated of Hazard Studies

MICROZONATION of the RMSS

CO

RR

EC

TIV

E &

PR

OS

PE

CT

IVE

M

GM

T

Seismic Risk

reduction

(reduce

current and

future

vulnerability)

Seismic Hazard and Risk

assessment for the AMSS,

educational, public health and

governmental agencies –

Presentation and publication of

results, investment plans for

prioritized critical infrastructure.

Land Use planning considering seismic

hazard (Microzonation)

Seismic code revision and update (MOP)

Public awareness program

Improve construction practices

Structural reinforcing/strengthening of

strategic infrastructure (portfolios)


Risk Reduction Measures

Measure Ongoing Research Future Work Needed

RE

AC

TIV

E M

AN

AG

EM

EN

T

Emergency

response:

identifying

most affected

areas to guide

assistance

Update of the seismic monitoring

center with a new software for

seismic data acquisition, data exchange

and automatic processing of EQ

recordings (preliminary locations and

magnitudes)

Improvement of the Seismic Network

(PNRR, 2012; JICA, 2014). Including

real time strong motion data

Correlation of instrumental seismic

intensity with strong motion

parameters

Shake Maps in terms of PGA (real

time strong motion records + models)

Shake Maps (real time strong

motion records + models) for

different spectral ordinates.

Response plans using specific

scenarios (DGPC)

(exposure and vulnerability data of

major cities)

Near real time damage and loss

estimations for emergency

response (exposure and

vulnerability data of major cities)

THANK YOU

probabilistic seismic risk assessment for the metropolitan

Documents