LESSONS FROM PAST NOTABLE EARTHQUAKES. Part IV Walter Hays, Global Alliance for Disaster Reduction, Vienna, Virginia, USA

PAST NOTABLE EARTHQUAKES NORTHRIDGE, CALIFORNIA JANUARY 17, 1994 GOOD FORTUNE--- IT HAPPENED ON A HOLIDAY

EARTHQAKES ARE DYNAMIC LABORATORIES FOR LEARNING AND CATALYSTS FOR BUILDING CAPACITY FOR DISASTER-INTELLIGENT & DISASTER-RESILIENT COMMUNITES

NORTHRIDGE, CALIFORNIA EARTHQUAKE NORTHRIDGE, CALIFORNIA EARTHQUAKE 4:31 AM ON JANUARY 17, 1994 M DEATHS $50 BILLION LOSS TRANSPORTATION AND UTILITY INFRASTRUCTURE FAILURES 4:31 AM ON JANUARY 17, 1994 M DEATHS $50 BILLION LOSS TRANSPORTATION AND UTILITY INFRASTRUCTURE FAILURES

OCCURRENCE

THE LOS ANGELES BASIN IS AT HIGH RISK FROM EARTHQUAKES

LOS ANGELES Los Angeles is located in the Los Angeles Basin where earthquakes have occurred many times on the well known San Andreas fault system and SOMETIMES on unknown “blind thrust faults.” Los Angeles is located in the Los Angeles Basin where earthquakes have occurred many times on the well known San Andreas fault system and SOMETIMES on unknown “blind thrust faults.”

LOCATION  The epicenter was located in Northridge, a suburb of Los Angeles.

 Southern California is prone to earthquakes because of its location near the boundary between two major tectonic plates: North America and Pacific.  Much, but not all, of the stress release happens on the San Andreas fault.

NORTHRIDGE EARTHQUAKE  SLIP ON A “BLIND” THRUST FAULT (I.E., DID NOT BREAK THE SURFACE) GEN- ERATED AN ALMOST PERFECT “BULLS EYE” EARTHQUAKE IN A MAJOR METROPOLITAN AREA

FAULT SYSTEM: NORTHRIDGE EARTHQUAKE

INADEQUATE RESISTANCE TO HORIZONTAL GROUND SHAKING EARTHQUAKES SOIL AMPLIFICATION PERMANENT DISPLACEMENT (SURFACE FAULTING & GROUND FAILURE) IRREGULARITIES IN ELEVATION AND PLAN FIRE FOLLOWING RUPTURE OF UTILITIES LACK OF DETAILING AND CONSTRUCTION MATERIALS INATTENTION TO NON- STRUCTURAL ELEMENTS CAUSES OF DAMAGE “DISASTER LABORATORIES”

IMPACTS BUILDINGS

LESSONS LEARNED FOR DISASTER RESILIENCE  ALL NOTABLE EARTHQUAKES  PREPAREDNESS PLANNING FOR THE INEVITABLE STRONG GROUND MOTION IS ESSENTIAL FOR COMMUNITY RESILIENCE.

GROUND SHAKING WESTERN USA

LESSONS LEARNED FOR DISASTER RESILIENCE  ALL NOTABLE EARTHQUAKES  PROTECTION OF BUILDINGS AND INFRASTRUCTURE IS ESSENTIAL FOR COMMUNITY RESILIENCE.

LOS ANGELES REGION LOS ANGELES REGION  Buildings, transportation infrastructure, utility corridors, and parking structures constructed in accordance with various codes/standards FAILED.

COLLAPSE OF A CONCRETE FRAME BUILDING

NORTHRIDGE EARTHQUAKE  THE BUILDING STOCK AND INFRA- STRUCTURE OF THE LOS ANGELES REGION WERE EXPOSED TO VERY STRONG GROUND SHAKING REACHING PGA > 1 G AT SOME LOCATIONS

A PROTECTION NIGHTMARE A PROTECTION NIGHTMARE

DAMAGE TO BRIDGE

THE UTILITY CORRIDOR: A PROTECTION NIGHTMARE THE UTILITY CORRIDOR: A PROTECTION NIGHTMARE  DISRUPTION OF UTILITY SERVICES, A FIRE, AND AN EXPLOSION QUICKLY CREATED THE CONDITIONS FOR A DISASTER.

NORTHRIDGE EARTHQUAKE NORTHRIDGE EARTHQUAKE  FLAWS WERE FOUND IN THE WELDED CONNECTIONS OF MANY MOMENT- RESISTING STEEL FRAME BUILDINGS

PROBABILISTIC MAPS OF PEAK GROUND ACCELERATION (PGA) AND SPECTRAL ACCELERATION (SA) ARE BASIC TOOLS USED IN BUILDING CODES AND INFRASTRUCTURE STANDARDS

LESSONS LEARNED FOR DISASTER RESILIENCE  ALL NOTABLE EARTHQUAKES  PREPAREDNESS PLANNING FOR THE INEVITABLE GROUND FAILURE IS ESSENTIAL FOR COMMUNITY RESILIENCE.

LIQUEFACTION IN A UTILITY CORRIDOR LIQUEFACTION IN A UTILITY CORRIDOR 

COLLAPSE OF UNIVERSITY PARKING STRUCTURE

LESSONS LEARNED FOR DISASTER RESILIENCE  ALL NOTABLE EARTHQUAKES  CAPACITY FOR EMERGENCY RESPONSE IS ESSENTIAL FOR COMMUNITY RESILIENCE.

DEALING WITH FIRE, AN EXPLOSION, DEATHS, AND LOSS OF FUNCTION DEALING WITH FIRE, AN EXPLOSION, DEATHS, AND LOSS OF FUNCTION

LESSONS LEARNED FOR DISASTER RESILIENCE  ALL NOTABLE EARTHQUAKES  CAPACITY FOR RECOVERY AND RECONSTRUCTION IS ESSENTIAL FOR COMMUNITY RESILIENCE.

EARTHQUAKE INSURANCE WAS A TOOL FOR RECOVERY  EARTHQUAKE INSURANCE SPREAD THE RISK AND SPEEDED UP RECOVERY BY FACILITATING THE “RESTORATION TO NORMAL”

IT TAKES TIME TO CORRECT FLAWS IN STEEL BUILDINGS IT TAKES TIME TO CORRECT FLAWS IN STEEL BUILDINGS 

IT TAKES TIME TO RESTORE REGIONAL TRANSPORTATION IT TAKES TIME TO RESTORE REGIONAL TRANSPORTATION

PLANNING FOR THE FUTURE  A NEW GENERATION OF POLICIES AND PROFESSIONAL PRACTICES WAS DEVELOPED FOR SITING, DESIGN, AND CONSTRUCTION IN CALIFORNIA AND OTHER EARTHQUAKE PRONE REGIONS OF THE USA.

PLANNING FOR THE FUTURE  THE INFORMATION, KNOWLEDGE BASE AND PROCESS NEEDED FOR DEVELOPING SCENARIOS FOR FUTURE EARTHQUAKE DISASTER PLANNING WERE CREATED.

SCENARIO EARTHQUAKE FOR SOUTHERN CALIFORNIA ADVANCE PLANNING SO THAT CALIFORNIA WILL BE READY WHEN THE INEVITABLE “BIG ONE” AND OTHERS RECUR Source: US Geological Survey

SOUTHERN CALIFORNIA AREA

QUAKE SHAKEOUT SCENARIO The goal in the ShakeOut Scenario is to identify the physical, social and economic consequences of a major earthquake in southern California, and in so doing, enable end users to identify what they can change now— before the earthquake—to avoid catastrophic impact after the inevitable earthquake occurs.

GROUND SHAKING: 60 % G SECONDS AFTER FAULT RUPTURE

THE M 7.8 SCENARIO QUAKE THE M 7.8 SCENARIO QUAKE The magnitude 7.8 SCENARIO earthquake will cause about 1800 deaths and $213 billion of economic losses. The magnitude 7.8 SCENARIO earthquake will cause about 1800 deaths and $213 billion of economic losses. These numbers are as low as they are because of aggressive retrofitting programs since 1994 that have increased the seismic resistance of buildings, highways and lifelines, and added economic resiliency. These numbers are as low as they are because of aggressive retrofitting programs since 1994 that have increased the seismic resistance of buildings, highways and lifelines, and added economic resiliency.

THE M 7.8 SHAKEOUT QUAKE The estimates of about 1800 deaths and $213 billion of economic losses are as large as they are because much more retrofitting could still be done. The estimates of about 1800 deaths and $213 billion of economic losses are as large as they are because much more retrofitting could still be done.

SUMMARY OF IMPACTS  57 DEATHS  9,000 INJURIES  HUNDREDS OF APARTMENT BUILDINGS DAMAGED  THOUSANDS OF COMMERCIAL BUILDINGS DAMAGED WHEN WELDS FAILED IN STEEL-FRAME BUILDINGS  PARKING FACILITIES COLLAPSED

SUMMARY OF IMPACTS  A RELATIVELY SMALL NUMBER OF DEATHS, PARTLY DUE TO HOLIDAY  OVER $50 BILLION DAMAGE WITH MORE THAN $5 BILLION IN EARTHQUAKE INSURANCE INDEMNIFICATION  UTILITY CORRIDOR FAILED  TRANSPORTATION SYSTEMS FAILED AGAIN

PRIMARY SOURCES OF INFORMATION ON THE LOMA PRIETA EARTHQUAKE ARE: 1) The US Geological Survey, 2) The California Geological Survey, and 3) the Earthquake Engineering Research Institute