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Chapter 7:Hazard Analysis—Earthquakes <br /> HSEAC identified the need prepare for these earthquakes by developing an understanding <br /> and knowledge of potential losses - to humans, buildings, infrastructure, businesses - and <br /> potential needs - hospital beds, shelter, transportation and utilities, debris removal - in order <br /> to mitigate both short and long term losses. <br /> 7.5.1.2 Hawaii County Assessment of'Critical Facilities <br /> The project engineering team consisting of the University of Hawaii, Martin & Chock, and <br /> Miyasato Kuniyoshi has conducted an all-hazard rapid visual screening (RVS) of critical <br /> facility buildings in the County of Hawaii. This included emergency command and control <br /> facilities, emergency first responders (fire stations, ambulance and police facilities),hospitals <br /> and clinics, and the two major airports (KOA and ITO). <br /> A HAZUS MH risk assessment model has been used to evaluate the expected losses for each <br /> building, using features determined from examination of the original construction plans and <br /> the RVS site visits. The vulnerability of a building can be measured by economic loss or by <br /> loss of functionality related to the extent of damage. Both of these risk measures have been <br /> analyzed for earthquake and hurricane hazards at an equivalent level of probability, so that an <br /> "apples to apples"comparison of effects was made possible. From the 80 buildings, a shorter <br /> candidate list of 32 structures that ranked highest in risk was first identified, and then <br /> building design and construction feature vulnerabilities were weighed in order to develop a <br /> list for review. In accordance with this FEMA project scope, two facility groups that ranked <br /> high based on the RVS and HAZUS analysis were designated by Hawaii County Civil <br /> Defense for more detailed evaluation and development of recommended mitigation <br /> procedures. A Benefit-Cost Analysis of the mitigation project construction funding was <br /> performed. This detailed evaluation provided the information necessary to submit a PDM <br /> grant application for retrofit of Kau Hospital, and prioritizes critical facilities most in need of <br /> future retrofits. <br /> 7.5.1.3 Structural Seismic Retrofit for Residential Post and Pier Homes <br /> A survey of 5') post and pier houses on the island of Hawaii was performed to determine the <br /> typical structural characteristics and variations in structural properties of these houses in the <br /> most vulnerable areas. The survey also investigated the extent of damage of these homes <br /> during the 2006 earthquakes along with any attempts to retrofit the houses at the time of <br /> survey. Based on this survey, a number of prototypical models of post and pier houses were <br /> analyzed for different levels of ground motion. A number of aspects of the houses were <br /> found to require retrofitting for even moderate levels of ground motion. <br /> From the analysis, three retrofit options were developed, with the applicability of each <br /> retrofit based on the location of the house and its structural properties. The retrofits are <br /> presented in a general format that can be applied to a wide range of houses without specific <br /> input from a structural engineer, except in special cases. Retrofit Option 1 is primarily a <br /> strengthening of connections using the existing post and pier foundation system, applicable <br /> in regions of low to moderate seismic hazard and for houses with moderate differential post <br /> heights. Retrofit Option 2 uses additional plywood shear walls between the ground and first <br /> 7-20 Hawaii Countv Multi-Hazard Mitigation Plan <br />