3_Fire Following Earthquake - Research Needs SCAWTHORN 15 Oct 09

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SPA Riskwww.sparisk.com

Fire Following Earthquake

Towards a PBEE Approach

Charles Scawthorn, S.E.President, SPA Risk LLC

Professor (ret.)

Kyoto University, Japan




Outline

• Problem of Fire Following Earthquake

• Review Recent Research and Models

(incldg. HAZUS)

• Review Mitigation Approaches

• Vision for PBEE-based approach for

reducing FFE risk




The Problem

1964

Valdez







Urban Conflagration• E bay hills fire (1991)

• numerous Southern California WUI fires

• ShakeOut (2008) Scenario

! 1,600 ignitions

The Problem Remains Today




Analysis







San Andreas M7.8 event: 150 yr return period;

300 yr since last rupture




ShakeOut (2008)




200 million sq. ft. building floor area ~ $65 billion

$100 million$ 10 million




Fire following earthquake study

• 1,600 ignitions requiring a fire engine• 1,200 exceed capability of 1st engine

• Orange County & LA basin: dozens of

large fires merge into conflagrations

destroying 100s of blocks• 200 million square feet burnt

! 133,000 single family dwellings

• Property loss: $65 billion

• No Santa Ana winds, not worst case• Study vetted by top state and county fire

officials

1989 Loma Prieta

1994 Northridge




San Francisco Community Action Plan for Seismic Safety (CAPSS)




Stochastic Ignitions following M7.9 San Andreas Event




Number of Buildings Completely Destroyed

– Shaking PLUS Fire Following Earthquake

FFE : 28%!

36%




High Rise Buildings• 1988 1st interstate bank bldg

• Meridian Plaza

• WTC

• 2004 Caracas

• 2005 Madrid

• 2008 Beijing

The Problem Today is Exacerbated




Recent Analytical Work – Physics Based Modeling

Fire Spread

• Himoto and Tanaka (Japan)

• Thomas et al (New Zealand)

• Lee and Davidson (USA)

Ignitions

• Williamson and Groner (PEER, 2000)




Physics-based simulation model

of post-earthquake fire spread

• Estimates the extent of fire damage to an urbanarea

• Application in Los Angeles County

• Modes of spread considered:

– Evolution of room fire

– Room-to-room spread within building by" Open doors

" Burn through walls and ceilings

" Leapfrogging

– Building-to-building spread by

" Radiation from room gas, window flame, roofflame

" Flame impingement from window flame

" Branding

Time:

mins

0

7 m/s wind

48163264128256512

Ignition

pointLee, S. (2009) “ Modeling Post-Earthquake Fire Spread ”,

PhD dissertation, R. Davidson, advisor Cornell University, 2009, in prep.




HAZUS

• FFE Model developed 1997

• Unchanged, despite known gross errors, until 2009

Comartin and Reis (2001)

• 2008 Review identified entire Program of Improvements




2009 HAZUS Ignition Equation

MR 4 – Issued 2 weeks ago (30 Sept 09)




FFE Mitigation

Water Supply• EBMUD, Hetch Hetchy…upgrades

Special Systems

• San Francisco AWSS (1906)

• San Francisco PWSS (1986 ! Loma Prieta Earthquake)• Vancouver DFPS (1990s)

• Vallejo, Oakland, Berkeley (mini-PWSSs, 1990s)

• Los Angeles? (ShakeOut review of LA

• Tokyo????

NERT / CERT citizen training programs

Gas / Electric Seismic Shutoff Valves




SFFD AWSS




Vancouver (BC) DFPS




Portable Water Supply Systems




Gas Shut-off Valves




PBEE FFE Vision

• Reduced Ignitions via PBEE-based mandated use of

gas and power seismic shutoff valves

• Improved reporting using ICT and RS (UAVs)

• PBEE-based reliable water supplies

/ special water supplies (LA!)

• Further growth of civilian first response (NERT…)




Mitigation PBEE ResearchGas/Power

Seismic ShutoffsAnalysis for where needed

based on urban density

RS detection UAV tactical detection

ICT rapid report Cellphone reporting of fires

Optimum

allocation ofresources

FD Decision-making model for

urban conflagration

Reliable Water Domestic Water Supply System

optimized to assure firewater;

Alternative Water Supply

Systems

Opt. Alloc.

Resources; ICT

evacuation

broadcast

FD Decision-making model for

conflagration; Evacuation

broadcast via mobile phones




Concluding Remarks

• Fire following earthquake a very significant risk

• FFE not appreciated due to highly nonlinear nature (only majorearthquakes)

• Highrise building FFE largely unexamined problem

• Substantial body of research on FFE and fire spread

• Integrated PBEE-based FFE Model is needed to optimally

mitigate this problem

• Many opportunities exist for reducing FFE risk, but not

currently being exploited

• FFE/PBEE Vision and requisite PBEE research leading to FFE

mitigation opportunities have been presented




www.risk-agora.org




GEM User Needs Survey

http://www.globalquakemodel.org/




Thank You

[email protected]

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3_Fire Following Earthquake - Research Needs SCAWTHORN 15 Oct 09

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