Development and implementation of damage matrices for united states buildings in accordance withems-98: collaborative research with applied technology council and usgsperiod of performance:…

Development and implementation of damage matrices for united states buildings in accordance withems-98: collaborative research with applied technology council and usgsperiod of performance: 7/15/2022 through 7/14/2023THE extent of the felt area and the geographical distribution of earthquake shaking are essential information needed in earthquake response. These are obtained with the use of macroseismic intensity, which describes the degree of ground shaking using different measures, including the extent of the building damage. Macroseismic intensity is also used within U.S. Geological survey (USGS) shakealert earthquake early warning (EEW) system. Macroseismic intensity is assigned using macroseismic scales that describe observations at different intensity levels (usually i to XII) based on earthquake effects on people, objects, buildings, and the environment. The modified mercalli intensity (MMI) scale is most commonly used in the united states. The USGS "did you feel IT" (dyfi) system relies on rapidly collecting macroseismic intensity data from internet users' shaking and damage reports for generating intensity maps immediately following felt earthquakes. The system has been in operation for over two decades, and over the past 15 years, several international seismological institutions have also implemented similar algorithms. However, this approach has a known limitation: IT is inadequate for assigning intensity values greater than VIII when significant building damage occurs. Above this intensity, robust intensity assignments require engineering knowledge of building type and damage levels, such as engineering or press reports and field reconnaissance. With the need to have seismologists and engineers review the higher intensity assignments, the problem of how to automatically evaluate and assign higher shaking intensities has not yet been fully solved. The european macroseismic scale (EMS-98, grunthal, 1998) provides detailed guidelines on assigning intensities above VIII and has been in use for over 15 years. However, EMS-98 is not applicable in the united states (and new zealand, among other countries) because domestic structure types are not represented in the damage matrices that form the basis of the method. This limitation also inhibits implementation of a globally applicable macroseismic intensity scale. This project will develop necessary extensions to EMS-98 methodology for use with the U.S. Building stock. The work will include a review of the common building types in the U.S. And assignment of each to a vulnerability class; a review of the intensity definitions in EMS-98; definitions of damage grades that are appropriate for the structure types identified; and an evaluation of the proposed intensity levels against intensity levels assigned by existing methods for past earthquake events. The work will also include extension of the EMS-98 methodology for use with the new zealand building stock to benefit from the similarities in structure types, as well as availability of documented damage information in this country from recent earthquakes. The project results, implemented in conjunction with existing EMS-98 guidance, will allow assignment of macroseismic intensities for moderate-to-large earthquakes in the united states and new zealand, consistent with information collected in europe for the last 15 years. The project findings will be documented in a comprehensive and illustrated guide to enable assigning a reliable intensity level for the area of interest. This capability will facilitate fast geographical damage distributions following a damaging earthquake. Moreover, results from this project can be used in discussions towards the generation of an international macroseismic scale to use at a global level and identify necessary tools for post-earthquake macroseismic data collection.