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2010 Haiti Earthquake:Recovery Effort and
Earthquake Risk Management
H. Kit Miyamoto, S.E.Miyamoto International
Topics
• The 2010 Earthquake• MTPTC Damage Assessment Program• Damage Repair Strategies• Earthquake Risk Management and Long Term Improvements
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MODIFIED MERCALLI INTENSITIESBased on intensities obtained by phone interviews, newscast interpretation and USGS/NEIC surveys. McCann & Mora, 2010
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AREAS AFFECTED BY LIQUEFACTION: Ground
cracks, lateral spread, sand blows, differential settlements
AREAS AFFECTED BY SLOPE FAILURES: Rock/falls, debris
flows, landslides
External geodynamic processes: Preliminary observations from satellite imagery and newscast interpretation
Reasons for Disaster
• Poor Materials and Construction• No engineering building codes• No license• No quality control• No risk management• NO EARTHQUAKE ENGINEERING
Damage Assessment Program
• A million people are living in camps and on streets.• Hurricane season is fast approaching.• Many buildings are safe but sit empty during the night.
• People need an official damage inspection program to tag building safety.
• ATC 20 technical protocol was customized for Haiti• Goal is to inspect 100,000 buildings in 57 days
Miyamoto ATC‐20 Methodology• Proven assessment program used in major US and Japan earthquakes
• 1989, M7.1 San Francisco, CA• 1994, M6.7 Los Angeles, CA• 1995, M7.1 Kobe, Japan
• Customized it for Haiti construction and enhanced by adding modules for demolition complexity and risk‐vulnerability. Both key data sets for recovery and reconstruction efforts.
• Demolition will be required for a number of buildings.
• Demolition efforts are divided into three categories:
– Easy: Building is very small, simple or has completely collapsed. Debris removal is easy and safe.
– Medium: Building has partial collapses and is 2‐3 stories tall. Debris removal requires engineering or construction knowledge for safety.
– Complex: Building is very tall or complex, has partial collapses or intermediate collapsed floors. Debris removal requires engineering for safety.
DEMOLITION
Structural Basics • Walls and frames• Redundancy• Brittleness/ductility• Degradation of
structural– Strength– Stiffness– Stability
Vulnerability Characteristics• Soils and Slope• Plan irregularity
―Torsion―Re‐entrant Corners―Large openings
• Vertical irregularity―Soft story―Set backs―Hillside―Short Column―Pounding
Damage Assessment Program• MI Earthquake Engineers trained over 200 selected National Engineers to conduct damage assessments and tagging.
• MI engineers provided deployment tactics and quality control.
• Coordination with Joint Task Force and IOM.• MTPTC tags the buildings
Deficiencies
• Poor Materials and Construction• No engineering building codes• No license• No quality control• No risk management• NO EARTHQUAKE ENGINEERING
Best Practices – California, Japan• Building codes with strong earthquake engineering requirements.
• All construction requires permit.• Projects includes plan review and construction inspection for quality control.
• Experience and testing requirements to get licenses for engineers, architects and contractors
Earthquake Forces and Structural Elements
Ground MotionA. B. “Earthquake Forces”
C. Shear walls Moment-Resistant frames Braced frames
Elastic vs. Inelastic DeformationInelastic Ductile Behavior
Deformed shapewith strong forceapplied
Final deformedshape after forceis removed
Deformed shape when a forceis applied
Springs backto original shape
Reinforced vs. Unreinforced Columns
Unreinforcedbrick piers
Ductile Reinforcedbrick piers
Strain, displ.
Stre
ss, f
orce
Strain, displ.S
tress
, for
ce
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ydisplacementforce
displacementforce
Seismic Resistant Building Design Philosophy
• Low level earthquakes produce elastic behavior
• Moderate level earthquakes may produce nonlinear behavior and some damage, primarily non‐structural
• High level earthquakes force nonlinear behavior and some damage, both non‐structural and structural
Reconstruction Factors• There has been no structural
building code or adequate construction regulation system of permitting and inspection.
• Haitians build their own homes based on common societal construction practices, using readily available materials.
We need to come up with indigenous and simple solutions that balances cost and earthquake safety.
Strategy for Repair• Technical Platform ‐ Repair methodology and options for
typical Haiti construction systems.
• Communications and Public Outreach – teach techniques and methodologies to repair and strengthen houses.
• Training – masons and contractors on proper construction methodologies for improved seismic resistance. E.g., confined concrete design and construction guides.
• Quality Assurance – Inspections by trained Haitian building inspectors.
Strategy for Repair
Communications and Public Outreach
• Radio, TV, newspaper advertising.
• Train the trainer classes.
• Trainers go to communities doing demonstrations on best practices – tools, materials, systems, methodologies
Long Term ImprovementsLong Term Quality Improvement Requires Better Engineering, Construction and Quality Assurance
• Education – classes and seminars on earthquake engineering
• Building Code – need to develop building codes for engineering and design.
• License – set up a licensing program for engineers, architects and contractors.
• Quality Assurance – set up permitting and construction inspection programs