EXPOSURE MODEL EXPOSURE MODEL LOCATION OF STRUCTURE IMPORTANCE AND VALUE OF STRUCTURE AND CONTENTS
VULNERABILITY MODEL VULNERABILITY MODEL QUALITY OF DESIGN AND CONSTRUCTION ADEQUACY OF LATERAL-FORCE RESISTING SYSTEM VULNERABILITY IS THE ULTIMATE CAUSE OF RISK
UNREINFORCED MASONRY, BRICK OR STONE REINFORCED CONCRETE WITH UNREINFORCED WALLS INTENSITY REINFORCED CONCRETE WITH REINFORCEDWALLS STEEL FRAME ALL METAL & WOOD FRAME VVIVIIVIIIIX 3530 25 20 15 10 5 0 MEAN DAMAGE RATIO, % OF REPLACEMENT VALUE CONSTRUCTION MATERIALS HAVE DIFFERENT VULNERABILITIES TO GROUND SHAKING
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”
AN INTRAPLATE EARTHQUAKE 400 KM FROM PLATE BOUNDARY-- “A SURPRISE”
GUJARAT EARTHQUAKE MAGNITUDE 7.7 JUST BEFORE 0900 ON A HOLIDAY (51 st Republic Day) MAGNITUDE 7.7 JUST BEFORE 0900 ON A HOLIDAY (51 st Republic Day) 20,000 DEAD 167,000 INJURED 400,000 HOMES DESTROYED 600,000 HOMELESS 20,000 DEAD 167,000 INJURED 400,000 HOMES DESTROYED 600,000 HOMELESS
STRICKEN URBAN CENTERS BHUJ, (150,000), 20 km from epicenter Devastated BHUJ, (150,000), 20 km from epicenter Devastated AHMEDABAD (5.6 MILLION) 50 multi-story buildings collapsed AHMEDABAD (5.6 MILLION) 50 multi-story buildings collapsed
Over 1 million structures damaged or destroyed.
A DISASTER is --- --- the set of failures that overwhelm the capability of a community to respond without external help when three continuums: 1) people, 2) community (i.e., a set of habitats, livelihoods, and social constructs), and 3) complex events (e.g., earthquakes, floods,…) intersect at a point in space and time.
THE REASONS ARE... When it does happen, the functions of the community’s buildings and infrastructure can be LOST for long periods.
THE REASONS ARE... The community is UN- PREPARED for what will likely happen, not to mention the low-probability of occurrence—high- probability of adverse consequences event.
THE REASONS ARE... The community has NO DISASTER PLANNING SCENARIO or WARNING SYSTEM in place as a strategic framework for early threat identification and coordinated local, national, regional, and international countermeasures.
THE REASONS ARE... The community LACKS THE CAPACITY TO RESPOND in a timely and effective manner to the full spectrum of expected and unexpected emergency situations.