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Earthquake Risk Reduction 3- Mitigation and ERR Program Development. Charles SCAWTHORN Junji KIYONO Kyoto University. Concepts and Terminology Hazard, Vulnerability & Risk Assessment Mitigation and ERR Program Development. Key Terms. Mitigation Risk Mitigation Alternatives
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Earthquake Risk Reduction 3- Mitigation and ERR Program Development Charles SCAWTHORN Junji KIYONO Kyoto University Concepts and Terminology Hazard, Vulnerability & Risk Assessment Mitigation and ERR Program Development
Key Terms • Mitigation • Risk Mitigation Alternatives • Operational • Risk Transfer • Develop the Program • Benefit-cost ratio • Acceptable risk • Implement the Program • Funding • Seismic retrofit • Emergency planning • Maintain the Program
Mitigation Four basic methods for Mitigation: • Structural • Locational • Operational • Risk Transfer
(f) active control system: ground motion sensor, processor, and controlled mass (d) base isolation (a) moment frame Bracing Types “K” “V” Chevron eccentric “X” diagonal (b) braced frame (e) damped frame (c) shear wall CPU Structural (using buildings as an example)
Actual fault Locational AP Zone Fault Shaking intensity map California Alquist-Priolo fault map, showing location of fault, and zone within which geologic investigation is required
EOC Director (Management) OperationalArea EOC Finance/ Administration Planning/ Intelligence Operations Logistics EOC Director (Management) Local Government EOC Planning/ Intelligence Finance/ Administration Operations Logistics Operational
Reinsurance company Insurance company Insurance company Insurance company Single buildings Single buildings Single buildings Risk Transfer
Risk Mitigation Alternatives EARTHQUAKE OCCURS RESULT MITIGATION PRIMARY HAZARDS:Faulting, Shaking, Liquefaction, Landsliding, Tsunami… Hazard mapping; ground remediation; tsunami walls… Demand (hazard) eliminated or reduced Bracing and strengthening, reduction of mass, base isolation, structural control… PRIMARY DAMAGE:Building / StructuralNonstructural / Equipment Capacity (strength…) increased SECONDARY HAZARD / DAMAGE:Fire, Hazmat, Flooding… Secondary demandseliminated or reduced Improved storage/infrastructure, better emergency response… PRIMARY LOSS:Life / Injury, Repair Costs, Function, Communications/Control… Improved emergency planning and response; insurance… Loss avoided or shared SECONDARY LOSS:Business / Operations InterruptionMarket Share, Reputation… Mitigation of damage and loss is possible at each step of earthquake loss process; earthquake occurs, primary hazards, primary damage, secondary hazard/damage, primary loss, and secondary loss.
Outline of Risk Reduction Program Data - Seismic hazard - Exposure - life - property - business / function - revenue - data - market share - reputation / image - Vulnerability - Assessment Y Stop Acceptable? Factors - Seismic environment? - Organization / decision-making - Responsibility / liability Y Acceptable? Pre-program Assess the Risk N Develop the Program Mitigation Options - Locational - Redundancy / backup - Move - Structural - Strengthen structures - Brace equpment / furnishings - Operational - Emerency Plan - Backup data - Transfer - Insurance - Contracts N Implement the Program Maintain the Program • Earthquakes are a problem, in the most general sense, solving a problem has three basic phases. • Phase 1: Understanding the problem • Phase 2: Finding the solution • Phase 3: Putting the solution into effect
Constr.Cost $ Tot Cost Design Level Life Cycle Cost Measuring Benefits Cost Damage Benefit Cost Ratio Internal Rate of Returnis the discount rate that “sets the net present value of the stream of net benefits [and costs] equal to zero”- effectively a measure of the return on investment
Assess the Risk • Identify the assets (people, property, function) at risk. • The corresponding losses for people, property and function are death and injury, financial loss, and business interruption, revenue, market share. • Establishing (i.e. quantifying) the seismic hazard • It is a representation of how strongly the ground will shake and how often it is likely to do so. • Developing performance objectives • No loss of life (no significant collapse hazard), limited property loss, no loss of essential equipment, and restoration of operation onsite or backup site within the time appropriate for the organization. • Performing first a risk screening and then, for selected structures, a more detailed review
Develop the Program • Developing the program, which consists of determining the acceptable risk, the opinions that exist for reducing the current risk to an acceptable level, the costs of doing that, and how it should be accomplished. • Having performed risk screening, facilities may be usefully grouped into several categories, such as • I. Probable high risk • II. Possible high risk • III. Probable low risk • The category I and category II facilities should be subjected to a more detailed analysis. • All the category I and II facilities can be ranked according to their risk, mitigation costs, or other criteria. The ranking is based on a benefit-cost ratio. • The final decision as to what facilities to mitigate will depend on available budget and is the final expression of the organization’s acceptable risk.
Implement the Program • Retaining seismic retrofit design professionals: • Initial investigation and screening • Detailed investigation and conceptual retrofit design • Construction documents and construction support • Funding the program; the following sources should generally considered when planning programs of seismic mitigation. • General operating and maintenance funds • Bond issues • Special use fee • Hazard mitigation grants • Tax preferences and credits • Coordinating with other parts of the organization; it is very important to include earthquake risk mitigation measures with other facets of an organization’s asset management program.
Maintain the Program • Organizations are dynamic and facilities, operations, and personnel are constantly changing. Thus documentation of the step taken, including the process and criteria, is an important step to complete. • As new facilities or operations are developed, the same or enhanced criteria can be applied to them, thus retaining the overall balance of earthquake mitigation program. • As new personnel join the organization, they can review the earthquake mitigation program documentation and maintain the overall goals.
Summary • An Earthquake Risk Reduction Program involves the following steps: • ASSETS: Identify and map the assets at risk – the people, property, business and cultural treasures. Where are they, how many are they, what is their value? • HAZARDS: Map the earthquake hazards that threaten these assets. Hazards include faulting, shaking, liquefaction, tsunami, landslide, fire. • VULNERABILITY: Assess the vulnerability of each asset to the hazards – is an highly vulnerable, moderately, or just low? • ANALYZE: Combine the information on Assets, Hazards and Vulnerability into a Risk Analysis. Map the areas of High Risk. • MITIGATION: Based on the assets, hazards and vulnerabilities, identify various ways in which the risk can be lowered. Select the mitigation method that makes the most sense – ie, is most effective for the least cost. • DEVELOP THE PROGRAM: Having a mitigation package, gather community support and find ways to pay for the mitigation. Develop a Plan for doing the mitigation over a several year timeframe. • IMPLEMENT THE PROGRAM: Do it. Don’t stop. Earthquakes won’t wait.