Soil
Dynamics
and
Earthquake
Engineering
30
(2010)
1319-1328
SOIL
DYNAMICS
ERRIFICSJAILE
ENGINEERING
Contents
lists
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at
ScienceDirect
Soil
Dynamics
and
Earthquake
Engineering
ELSEVIER
journal
homepage:
www.elsevier.com/locate/soildyn
Seismic
microzonation
and
earthquake
damage
scenarios
for
urban
areas
Atilla
Ansal*,
Ash
Kurtulus,
Gokce
Tontik
Bogazici
University,
Kandilli
Observatory
and
Earthquake
Research
Institute,
Cengelkoy,
34684
Istanbul,
Turkey
ARTICLE
INFO
ABSTRACT
Article
history:
Received
23
July
2009
Received
in
revised
form
29
May
2010
Accepted
12
June
2010
A
methodology
for
seismic
microzonation
and
earthquake
damage
scenarios
may
be
considered
as
composed
of
two
stages.
In
the
first
stage,
microzonation
maps
with
respect
to
estimated
earthquake
characteristics
on
the
ground
surface
are
generated
for
an
investigated
urban
area.
The
effects
of
local
geological
and
geotechnical
site
conditions
are
taken
into
account
based
on
site
characterization
with
respect
to
representative
soil
profiles
extending
down
to
the
engineering
bedrock
1D
site
response
analyses
are
performed
to
calculate
earthquake
characteristics
on
the
ground
surface
using
as
many
as
possible,
hazard
compatible
real
acceleration
time
histories.
In
the
second
stage,
vulnerability
of
buildings
and
pipeline
systems
are
estimated
based
on
site-specific
ground
motion
parameters.
A
pilot
study
is
carried
out
to
evaluate
seismic
damage
in
a
district
in
Istanbul,
Turkey.
The
results
demonstrate
the
significance
of
site
characterization
and
site
response
analysis
in
calculating
the
earthquake
characteristics
on
the
ground
surface
in
comparison
to
simplified
empirical
procedures.
©
2010
Elsevier
Ltd.
All
rights
reserved.
1.
Introduction
Seismic
microzonation
and
earthquake
loss
estimation
scenar-
ios
are
among
the
essential
tools
needed
for
city
planning,
disaster
preparedness,
risk
reduction,
hazard
mitigation
decisions,
and
urban
rehabilitation
actions
in
earthquake
prone
areas.
Loss
estimation
due
to
possible
future
earthquakes
in
an
urban
environment
is
a
very
complex
process
that
requires
detailed
building
and
lifeline
inventories,
probabilistic
or
deterministic
analyses
of
seismic
hazard
on
the
ground
surface
and
assessment
of
vulnerability
of
the
inventories
due
to
the
estimated
earth-
quake
characteristics.
There
are
basically
three
phases
that
control
the
earthquake
damage
estimation
process:
(1)
seismic
hazard
assessment
and
input
ground
motion
characteristics,
(2)
modification
of
these
input
ground
motion
due
to
site
conditions,
and
(3)
vulnerability
formulations
to
estimate
damage
distribution.
All
these
three
stages
could
play
significant
role
on
the
outcome,
depending
how they
are
evaluated.
Several
methodologies
11-5]
have
been
developed
over
the
past
years
that
take
into
account
various
aspects
of
loss
estimation
process.
However,
none
of
these
loss
estimation
methodologies
involves
detailed
analysis
of
local
site
conditions
when
predicting
ground
motion
characteristics
on
the
ground
surface.
The
methodology
proposed
in
this
work
provides
a
loss
estimation
method
that
takes
local
site
effects
into
account
by
*Corresponding
author.
E-mail
address:
ansal@boun.edu.tr
(A.
Ansal).
0267-7261/$-see
front
matter
2010
Elsevier
Ltd.
All
rights
reserved.
doi:10.1016/j.soildyn.2010.06.004
performing
large
numbers
of
1D
site
response
analyses
using
Shake91
code
16].
A
software
tool
is
developed
to
apply
this
methodology
for
damage
scenario
predictions
in
urban
areas.
In
order
to
analyze
the
complex
process
for
conducting
microzonation
with
respect
to
different
earthquake
characteristics
on
the
ground
surface
and
to
calculate
damage
distributions
within
the
investigated
urban
environment,
it
is
essential
to
utilize
a
flexible
software
package.
The
main
purpose
of
such
an
earthquake
scenario
software
tool
besides
performing
microzonation
and
earthquake
damage
scenarios
for
the
investigated
area
is
to
have
the
capability
to
conduct
parametric
studies
for
evaluating
the
range
of
variability
induced
in
these
three
stages
and
to
assess
the
significance
of
the
related
factors
in
the
estimated
final
damage
distributions.
2.
Methodology
for
microzonation
and
damage
scenarios
The
proposed
methodology
is
composed
of
two
main
phases.
The
first
phase
involves
generation
of
microzonation
maps
with
respect
to
earthquake
ground
shaking
parameters
due
to
the
selected
regional
earthquake
hazard
scenario.
In
the
second
phase,
vulnerability
of
buildings
and
pipelines
are
estimated
based
on
the
calculated
earthquake
ground
shaking
parameters.
Results
are
displayed
in
damage
distribution
maps
for
buildings
and
pipeline
systems
that
are
produced
in
GIS
environment.
The
first
step
is
to
adopt
a
grid
system
that
divides
the
investigated
urban
area
into
cells
(typically
250
m
x
250
m)
according
to
the
availability
of
geological,
geophysical,
and
geotechnical
data.
Variations
of
earthquake
shaking
parameters