Seismic Disaster Mitigation in Pakistan

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26 Νοε 2013 (πριν από 3 χρόνια και 8 μήνες)

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1

Seismic Disaster Mitigation in Pakistan

Dr. Qaisar Ali

Associate

Professor

and

Deputy

Director

Earthquake

Engineering

Center

Department

of

Civil

Engineering

NWFP

University

of

Engineering

and

Technology,

Peshawar

Pakistan


2

Roadmap


Basic terminology
-

hazard, risk, vulnerability and disaster



Factors contributing to seismic disaster mitigation



Hazard assessment in context of the Oct 08 earthquake



Vulnerability of structures in context of the Oct 08
earthquake



Recommendations for seismic disaster mitigation in Pakistan

3

Hazard, Risk, Vulnerability

and Disaster ?




How these terms are interconnected



4

Disaster

An

event

causing

widespread

human

or

material

losses

which

exceeds

the

ability

of

the

affected

community

to

cope

using

its

own

resources

5

Disaster risk = Hazard x Vulnerability

Source: Satoru NISHIKAWA

Cabinet Office JAPAN

6

Implications of Disasters


A

single

disaster

can

wipe

out

annual

GDP

of

a

country
.




Losses

from

the

current

earthquake


80
,
000

dead


200
,
00

injured


4

million

homeless


Economic

losses

more

than

USD

5

billion

Disaster Reduction is a
MUST
for
Sustainable Development


7

Disaster mitigation


Pre
-
earthquake

scenario


Realistic

hazard

assessment


Reducing

vulnerability

through


Seismic

resistant

design

of

structures
.


Implementation

of

code,

inspection

and

monitoring

mechanism
.



Post
-
earthquake

scenario


Emergency

preparedness

and

planning


8

Seismic hazard zoning of Pakistan and the current
earthquake


Geophysical center Quetta,
Met deptt. of Pakistan

9

Realistic seismic hazard assessment


Realistic

seismic

hazard

assessment

is

crucial

because

placing

a

low
-
seismicity

region

in

a

high

hazard

zone

will

require

construction

of

costly

structures

thereby

making

them

uneconomical
.

Similarly,

placing

a

high
-
seismicity

region

in

a

low

hazard

zone

will

allow

construction

of

relatively

weaker

structures

thereby

making

them

vulnerable

to

collapse

during

an

earthquake
.


10

Seismic Vulnerability



Low

Seismic

capacity

of

buildings

due

to

low

quality

of

material,

improper

design

and

construction
;

buildings

constructed

on

loose

soil,

or

constructed

in

areas

prone

to

liquefaction

and

land

slides

etc
.

will

make

the

structures

vulnerable

to

collapse

during

an

earthquake
.




11

Seismic vulnerability with respect to
the Oct 08, earthquake

12

Stone

masonry

buildings

constitute

around

40
%

of

the

total

building

stock
.

(
20
%

of

it

in

cities

and

80
%

in

villages)
.


Approx

95

%

of

buildings

either

completely

collapsed

or

got

severely

damaged
.

Undressed stone masonry

Dressed stone masonry

Smooth round stones in mud mortar, or low quality cs mortars,
no bond beams, no proper connections

13

30
%

of

the

total

building

stock

(
100
%

of

it

in

cities,

negligible

in

villages)

was

un
-
reinforced

cement

concrete

block

masonry

having

RC

roof

slab,

out

of

which

approx

50
%

either

collapsed

or

got

severely

damaged
.

Low

quality

concrete

blocks

laid

in

mud

mortar,

or

low

quality

cs

mortars,

no

bond

beams,

no

proper

connections

14

Total

stock

of

brick

masonry

building

constitutes

around

20
%
,

(
100

%

in

cities,

negligible

in

villages),

out

of

which

less

than

5
%

collapsed

and

around

15
%

got

severely

damaged
.


By

and

large

the

brick

masonry

has

performed

very

well
.

Brick masonry building Muzafarabad

15

Improper lap length

Less than 5% of the total building stock consisted of
RC frame

structures with brick or block masonry infill walls., 100% in cities.

Generally performed well,

The collapse and damage were found to
be the result of improper design, detailing and low quality material.

16

Strong
-
beam weak
-
column

17

Incredible


18

Improper lateral reinforcement

19

20

Water tanks collapse occurred as far as 200
km from the epicenter

21

Original position of
deck

1 meter
displacement

Life lines
---
Bridges

22

Pipe lines



transmission lines



23

Massive

land

sliding

washed

out

entire

villages

24

Letter written by Sony, a student in Nepal

Ref: Program on Educational Building, OECD




Approx 17,000 school children killed

25

None
-
existence of


seismic design guidelines and building codes.


site specific ground characteristics for seismic
design.


scientifically determined indigenous material
properties.


trained professionals for carrying out construction
activities in seismic prone areas


awareness of general public for realizing the
seismic risk.


Implementing/regulating and inspection mechanism
for construction monitoring

Issues contributing towards seismic
vulnerability

26

Emergency preparedness and
planning




In

the

post
-
earthquake

scenario

the

quantum

of

disaster

can

increase

enormously

due

to

lack

of

effective

emergency

preparedness

and

planning

strategies
.





27

Measures to be taken to
avoid disasters in future ?

28

29

Short Term measures


For

the

reconstruction

of

the

affected

areas,

general

seismic

guidelines

and

building

recommendations

can

be

adapted

from

already

established

international

codes
.

This

should

act

like

an

interim

code

and

not

as

a

permanent

code

for

the

country
.

To

develop

a

proper

seismic

code

for

the

country

will

take

time
.



The

enactment

of

a

law

for

strict

enforcement

of

these

recommendations

is

also

required
.



Training

should

be

imparted

to

the

contractors,

masons,

construction

supervisors

and

local

government

hierarchy

at

the

union

council

and

tehsil

level

for

effective

reconstruction

and

rehabilitation

activities
.



The

design

and

construction

of

educational

institutions,

hospitals

and

other

important

government

buildings

should

be

given

special

attention
.

The

EEC

should

be

involved

in

this

process
.

30

Short Term measures
---


Construction

of

new

buildings

in

the

areas

prone

to

landsliding

and

liquefaction

should

be

avoided
.



Rapid

assessment

of

damaged

public

and

private

buildings

is

crucial
.

There

should

be

authorized

qualified

technical

professionals

to

carry

out

these

activities
.

(Fear

among

the

people

is

so

high

that

even

some

slightly

damaged

buildings

have

been

declared

as

uninhabitable
.
)



Repair,

strengthening

and

/or

retrofitting

of

existing

buildings

deficient

in

seismic

capacity

is

also

vital
.



31

Improving

the

seismic

performance

of

masonry

structure
-
general

guidelines

(ref

Eurocode
-
8
)

Note
:

such

arrangement

provide

overall

integrity

and

stability

to

the

structure
.


32

33

Long term measures


Installation of strong motion net work



Development

of

seismic

hazard

maps

based

on

PGA

and

PGV,

liquefaction

and

landslide

maps,

micro

zoning

for

highly

seismic

prone

regions

etc
.



Development of seismic code for the country



Seismic

risk

assessment

for

various

categories

of

buildings

and

engineering

structures
.



Structural

assessment

of

important

buildings

such

as

dams,

long

span

bridges,

educational

institutions,

hospitals,

secretariat

etc

and

their

strengthening,

if

required
.


34

Long term measures (contd)


Technology

development

for

low

cost

base

isolation

and

damper

systems

for

brittle

structures
.


Development

of

repair

and

strengthening

techniques

for

seismically

distressed

local

structural

systems
.


Development

of

disaster

mitigation

methodologies
.


Seismic

risk

assessment

for

sustainability

of

life

lines

including,

highways,

railways,

Gas,

Sewerage

and

Water

pipe

lines

and

electricity

transmission

lines

etc
.

35

Proverb by Japanese Physics Scientist Dr.
Torahiko



Natural disasters will hit us by
the time people have forgotten
about it”







36

Thanks