Cascading Failures Across Interdependent Infrastructure...

Cascading Failures Across Interdependent Infrastructure Systems

Leonardo Dueñas-OsorioAssistant Professor

Department of Civil and Environmental EngineeringRice University

Workshop on Seismic Risk and Management of Transportation Networks

Pacific Earthquake Engineering Research CenterBerkeley, California

March 18, 2009

Presentation Outline

1. Overview of Cascading Failures

2. Multiple Infrastructure Systems

- Economic sector approach

- Physical network approach

3. Research Agenda

1. Cascading Failures Overview • Cascading Failures: Propagation of local failures as a

chain reaction that results in a disproportionately large portion of the system failed.

Blackouts

Natural Hazards

2. Inter-dependent Cascades (1)• Spatially co-located infrastructures

Physical-level approach

Economic-level approach

2. Inter-dependent Cascades (2)• Physical network approach

Data Requirements

- Topology

- Location

- Direction

- Strength

2. Inter-dependent Cascades (3)• Power transmission network

2. Inter-dependent Cascades (4)• Water distribution network

2. Inter-dependent Cascades (5)• Practical Interdependent adjacency

Pi | Wjij p)P Failure| WFailure P( =Matrix of conditional

probabilities of failure

2. Inter-dependent Cascades (6)• Seismic hazard for return period of 475 years

0 0.5 1 1.50

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

PGA (g)

P(W

ater

DS

> d

si |

PG

A)

20% Connectivity loss50% Connectivity loss80% Connectivity loss

2. Inter-dependent Cascades (7)• Water distribution system fragility

Increased fragility

Pro

babi

lity

of E

xcee

ding

CL

0 0.5 1 1.50

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

PGA (g)

P(W

ater

DS

> 2

0% C

L | P

GA

and

Pw

|p)

P(W Nf | PNf) = PW Nf

2. Inter-dependent Cascades (8)• Interdependent fragility curves at CL = 20%

Independent

P (

DS

> 2

0% C

L | P

GA

)P

roba

bilit

y of

Exc

eedi

ng C

L

0 0.5 1 1.50

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

PGA (g)

P(W

ater

DS

> 2

0% C

L | P

GA

and

Pw

|p)

P(W Nf | PNf) = PW NfP(W Nf | PNf) = 0.2

2. Inter-dependent Cascades (8)• Interdependent fragility curves at CL = 20%

Independent

Interdependent

P (

DS

> 2

0% C

L | P

GA

)P

roba

bilit

y of

Exc

eedi

ng C

L

0 0.5 1 1.50

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

PGA (g)

P(W

ater

DS

> 2

0% C

L | P

GA

and

Pw

|p)

P(W Nf | PNf) = PW NfP(W Nf | PNf) = 0.2P(W Nf | PNf) = 0.5P(W Nf | PNf) = 1.0

2. Inter-dependent Cascades (8)• Interdependent fragility curves at CL = 20%

Independent

Interdependent

P (

DS

> 2

0% C

L | P

GA

)P

roba

bilit

y of

Exc

eedi

ng C

L

2. Inter-dependent cascades (9)• Time-evolving interdependent effects (I = 50%)

Wat

er S

yste

m C

L

2. Inter-dependent cascades (10)• Sensitive zone for interdependent effects

3. Research Agenda

• Incorporate transportation infrastructure in the interdependent analysis of utility systems.

• Develop theory of interdependent system reliability

• Study system decoupling to halt escalation of failures

• Determine optimal strategies for lifeline hardening

• Secure detailed infrastructure data availability