IMPACTS OF EARTHQUAKES ON WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS

IMPACTS OF EARTHQUAKES ON

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND

DISTRIBUTION SYSTEMS

Walter Hays, Global Alliance for Disaster Reduction, University of

North Carolina, USA

OVERVIEW OF EARTHQUAKE RISK

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS FACE DIFFERENT RISKS FROM THE POTENTIAL DISASTER

AGENTS OF EARTHQUAKES

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS

• Have POINT-SENSITIVE and AREA-SENSITIVE components, …

• which have varying vulnerabilities when exposed to the TIME – and SPACE- DEPENDENT potential disaster agents of EARTHQUAKES.

TIME HISTORY AND SPECTRUM

WATER,RESERV.,WATER,RESERV.,AQUEDUCTS, AQUEDUCTS,

PIPELINES,, AND PIPELINES,, AND DISTRIBUTION DISTRIBUTION

SYSTEMSSYSTEMSDATA BASES DATA BASES AND INFORMATIONAND INFORMATION

HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS

•EARTHQUAKES•INVENTORY•VULNERABILITY•LOCATION

RISK ASSESSMENTRISK ASSESSMENT

RISK

ACCEPTABLE RISK

UNACCEPTABLE RISK

GOAL: DISASTER GOAL: DISASTER RESILIENCERESILIENCE

PREPAREDNESS•PROTECTION•EMERGENCY RESPONSE•RECOVERY

PPLICIES:FOR PPLICIES:FOR RESILIENT SYSTEMSRESILIENT SYSTEMS

DAMAGE; DAMAGE; INJURIESINJURIES

ELEMENTS OF ELEMENTS OF UNACCEPTABLE RISKUNACCEPTABLE RISK

FAILURE; FAILURE; DEATHSDEATHS

LOSS OF LOSS OF FUNCTIONFUNCTION

ECONOMICECONOMIC

LOSSLOSS

RISKRISK

EARTHQUAKEHAZARD MODEL

SEISMICITY TECTONICSETTING &

FAULTS

THE BASIC FAULT MODELS

Strike-Slip Reverse

Normal

EXPOSUREMODEL

LOCATION OFWATER

SYSTEMS

IMPORTANCE AND VALUE OF SYSTEM

AND CONTENTS

VULNERABILITYMODEL

QUALITY OF DESIGN AND

CONSTRUCTION

ADEQUACY OF LATERAL-FORCE

RESISTING SYSTEM

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS

• Vulnerability is a function of materials, age, maintenance, and the system’s exposure as a site-specific, or a spatially- distributed above-or-below-ground system.

UNREINFO

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INTENSITYINTENSITY

REINFORCED CONCRETE WITH REINFORCEDWALLS

STEEL FRAME

ALL METAL & WOOD FRAME

VV VIVI VIIVII VIIIVIII IXIX

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CONSTRUCTION MATERIALS HAVE DIFFERENT VULNERABILITIES TO GROUND

SHAKING

COMMENTS ON DAMAGE• MMI VI DENOTES TO ONSET OF DAMAGE

DUE TO LIQUEFACTION • MMI VII DENOTES DAMAGE FROM

CRACKING; APPROXIMATELY 12% g• MMI VIII DENOTES SEVERE DAMAGE,

TYPICALLY AT JOINTS OF PIPES; APPROXIMATELY 25 % g

• MMI IX DENOTES VERY HEAVY DAMAGE, MANY BREAKS/KM; 50 %^ g.

TECTONIC DEFORMATION

EARTHQUAKE

TSUNAMI

GROUNDSHAKING

FAULT RUPTURE

FOUNDATION FAILURE

SITE AMPLIFICATION

LIQUEFACTION

LANDSLIDES

AFTERSHOCKS

FIRE

DAMAGE/LOSSDAMAGE/LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/ LOSSDAMAGE/ LOSS

DAMAGE/LOSSDAMAGE/LOSS

INADEQUATE RESISTANCE TO HORIZONTAL GROUND SHAKING

EARTHQUAKES

SOIL AMPLIFICATION

PERMANENT DISPLACEMENT (SURFACE FAULTING, LIQUE-FACTION

& LANDSLIDES)

IRREGULARITIES IN ELEVATION AND PLAN, AND [OOR ROUTE

TSUNAMI IMPACTS

POOR DETAILING AND WEAK CONSTRUCTION MATERIALS

FRAGILITY OF NON-STRUCTURAL ELEMENTS

CAUSES OF DAMAGE

“DISASTER LABORATORIES”

EXAMPLES OF FAILURES (AND ALMOST FAILURES) IN PAST EARTHQUAKES

INADEQUATE SEISMIC DESIGN PROVISIONS (I.E., BUILDING CODES )

MEAN 1) INADEQUATE RESISTANCE TO HORIZONTAL GROUND SHAKING2) COLLAPSE AND FAILURE OF

ABOVE-GROUND SYSTEMS

UNDERGROUND PIPELINES AND DISTRIB-UTION SYSTEMS NEED PROTECTION

• A UTILITY CORRIDOR IS VULNERABLE TO LOSS OF FUNCTION WHEN IT IS ROUTED THROUGH SOILS THAT ARE SUSCEPTIBLE TO LIQUEFACTION. (USA 1995)

INADEQUATE SEISMIC DESIGN PROVISIONS (I.E., WATER SYSTEM STANDARDS) AND THE ROUTING)

MEAN 1) SUSCEPTIBILITY TO PERMANENT GROUND FAILURE (LIQUEFACTION,

LANDSLIDES), 2) FAILURE OF BELOW-GROUND

SYSTEMS

ABOVE-GROUND SYSTEMS NEED PROTECTION FROM LANDSLIDES

• RESEVOIRS ARE SUSCEPTIBLE TO LANDSLIDES INDUCED BY EARTHQUAKES. (CHINA 2008)

AQUEDUCTS: ABOVE-GROUND SYSTEMS THAT CARRY WATER FROM “A” TO “B”

• AQUEDUCTS ARE SUSCEPTIBLE TO LANDSLIDES INDUCED BY EARTHQUAKES. (ARIZONA);

AQUEDUCTS: ABOVE-GROUND SYSTEMS THAT CARRY WATER FROM “A” TO “B”

• ELEVATED AQUEDUCTS ARE VERY SUSCEPTIBLE TO GROUND SHAKING.

CHINA 2008: RESERVOIRS NEED PROTECTION IN AN EARTHQUAKE

JAPAN 2011: ABOVE GROUND SYSTEMS NEED PROTECTION IN AN EARTHQUAKE

SICHUAN, CHINA: ABOVE GROUND SYSTEMS NEED PROTECTION

HAITI 2010: ABOVE-GROUND SYSTEMS NEED PROTECTION

TURKEY 2010: ABOVE GROUND SYSTEMS NEED PROTECTION

KEY CONSIDERATIONS FOR PROTECTIVE DESIGN AND

SMART ROUTING

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION

SYSTEMS

WATER RESERVOIRS, PIPELINES, AQUEDUCTS, AND DISTRIBUTION SYSTEMS

• Above-ground siting makes water- reservoirs and aqueducts more vulnerable to earthquake ground shaking than the buried pipelines and distribution systems are.

EARTHQUAKE SCENARIOS

A DISASTER RISK ASSESSMENT TECHNIQUE

FOR USE IN AN EARTHQUAKE-PRONE AREA

DESIGN SCENARIOS • Distributed Systems: The risks

need to be assessed in terms of regional ground shaking and ground failure maps; ---

• Non-distributed systems: Assess risks in terms of site-specific criteria.

EXAMPLE: PROBABILISTIC GROUND SHAKING HAZARD

MAPSPGA: 10 % P(EXCEEDANCE) IN

50 YEARSSOURCE

GLOBAL SEISMIC HAZARD ASSESSMENT PROGRAM

US GEOLOGICAL SURVEY

A probabilistic ground shaking hazard map integrates physical properties determined from geology, geophysics, and seismology in a consistent way to define:1)Seismic source zones2)Regional seismic wave attenuation rates

• Seismic Source Zones: Each zone has its own unique spatial and temporal distribution of faults, magnitudes and recurrence intervals.• Regional Seismic Attenuation Rates: seismic waves decay more rapidly near a plate boundary than far from the boundary.

GROUND SHAKING HAZARD ASSESSMENTGROUND SHAKING HAZARD ASSESSMENT

ATTENUATION

SESMIC SOURCES RECURRENCE

PROBABILITY

Each map shows relative levels of the ground shaking hazard on a small scale in terms of the mapping parameter: peak ground acceleration (and sometimes MMI).

PEAK GROUND ACCELERATION

Peak ground acceleration correlates best with the short-period asymptote of the response spectrum, and is related to how a short waste water facility would respond to ground shaking.

The maps are most useful for small-scale applications such as comparison of the relative ground shaking hazard between the end-points of a long, distributed water pipeline system.

• The mapping parameter, peak ground acceleration, is not as good a descriptor of how the ground actually shakes as is a time history

• The response spectrum of a time history is an approximation of how a water system element might respond to ground shaking of a certain period.

• The regional-scale peak ground acceleration maps are not appropriate for site-specific design.

• Regional maps do not incorporate information on soil properties (e.g., shear wave velocity; data related to liquefaction; slope stability).

• Soils data require sampling and mapping on a larger scale.

http://www.seismo.ethz.ch/gshap/eastasia/

PGA SCALE FOR MAPS

Afghanistan

RESILIENT RESILIENT SYSTEMSSYSTEMS

RISK ASSESSMENT

• VULNERABILITYVULNERABILITY

• EXPOSUREEXPOSURE

• EVENTEVENT

POLICY ASSESSMENT

• COSTCOST

• BENEFITBENEFIT

•CONSEQUENCESCONSEQUENCES

RISK ASSESSMENT LEAD TO POLICY RISK ASSESSMENT LEAD TO POLICY IMPLEMENTATIONIMPLEMENTATION

““WATER WATER SYSTEMS”SYSTEMS” EXPECTED EXPECTED

LOSSLOSS