Seismic Hazard Assessment of Oregon: Analysis of Earthquake Resilience within State Wide Infrastructure and the Cost of Retrofitting

Title
Seismic Hazard Assessment of Oregon: Analysis of Earthquake Resilience within State Wide Infrastructure and the Cost of Retrofitting
Author
Curt Knott
Date
May 28, 2020
Type
Text; Image; StillImage
Identifier
aes/258
Language
eng
Abstract
Earthquakes are an imminent threat looming over the Pacific Northwest. This threat is radically increased due to the lack of structural integrity of buildings in the region, especially in densely populated areas, and inadequate planning as to where buildings were constructed. It is critical that states such as Oregon and Washington retrofit or reconstruct existing buildings to reduce the risks associated with a potential major mega-thrust earthquake generated by the Cascadia Subduction Zone. Portland, Oregon’s largest city, is currently one of the most vulnerable cities in the US to a major earthquake. If a large earthquake struck the Pacific Northwest, Portland would be greatly affected because most of the buildings within the city were constructed before the state-wide building codes were enacted in 1973, and well before the first state wide seismic building codes (enacted in 1993). In an ideal scenario, reconstructing every building to be earthquake safe and up to code would be the plan. However, reconstructing the buildings of an entire city would be expensive, complicated, and extremely time consuming. For those reasons, this study focused on different retrofitting techniques and their costs, and the necessity for certain buildings to be reconstructed. Retrofitting costs were compared to the cost of demolition and reconstruction of old buildings, in order to determine the most economically viable course of action for preventing loss of life and minimizing structural losses in Oregon. Buildings are not the only type of infrastructure at risk, as bridges are also susceptible to being damaged during earthquake events. On the Oregon coast, many towns are connected both inland and to each other by bridges. Waldport is such an example, having all 3 of its major roads on bridges less than a mile out of town. According to Oregon State University, most of the coastal bridges in the state have a very high chance of collapsing and/or sustaining major damage, or being inundated with water due to a subsequent tsunami. The risk of infrastructure collapse (and potential loss of life due to collapse) and cost of retrofitting is the first portion of data being assessed. The second section of data being analyzed is the amount of people that would be incapable of moving to safety due to collapse or damage, and the access (or lack thereof) of emergency response services to isolated areas following a seismic hazard event.
Description
This presentation was delivered on May 28, 2020 at Western Oregon University Academic Excellence Showcase (Monmouth, OR).
Rights
Western Oregon University Library has determined, as of 05/27/20, this item is in copyright, which is held by the author. Users may use the item in accordance with copyright limitations and exceptions, including fair use. For other uses, please ask permission from the author.
http://rightsstatements.org/vocab/InC/1.0/
Department
Earth/Physical Science
Faculty Sponsor
Jeff Templeton