This award is an outcome of the NSF 08-519 program solicitation ''George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)'' competition and includes the Oregon State University (lead institution), Colorado State University (subaward), and Texas A&M University, Kingsville (subaward).

The current tsunami evacuation strategy in the U.S. puts large populations at high risk because it requires everyone to evacuate the flooded areas and does not consider the possibility of using tall buildings for shelter. Part of the unwillingness to adopt vertical evacuation strategies stems from an inability to estimate the damage level in the flooded area for a range of building types, including reinforced concrete (e.g., modern hotel), unreinforced concrete masonry units (e.g., older motel, light commercial) and light-frame wood (mostly residential and some light commercial) structures. The goal of this project is to model building damage by studying water flow and debris hazard of collapsed buildings in the flooded areas. This will help us understand the expected damage to cities and town and to design buildings to withstand these forces.

As a first step of this new approach, we will focus on residential (light-frame wood) buildings which make up 90% of the building stock in the US and are where people spend approximately half of the hours in their day, Because of the sheer number of residential buildings in these coastal communities, understanding tsunami impact on these structures and the expected damage level is necessary to reduce damage and loss of life.

The goals of this NEESR-II project are to (1) develop a methodology to assess the risk of residential structures to tsunami inundation and wave forces through a systematic experimental study coupled with a numerical probability of failure analysis; (2) enable the development of innovative retrofit products by developing a structural testing protocol that is representative of hydraulic impact/forces during a tsunami; and (3) refine the current hydraulic force equation in ASCE 7 based on a series of wave basin tests to account for building density and other variables. This transformative project builds on the knowledge base of tsunami inundation at regional scales and the tsunami-structure understanding at the building scale from other NEESR projects. This project also integrates new large-scale physical modeling and numerical modeling efforts to mitigate both structural risk to building damage and loss of life in a community-wide tsunami inundation event.

To accomplish the project objectives, several large-scale tests will be conducted over three years at the NEES Tsunami Facility at Oregon State University using both the Large Wave Flume and Tsunami Wave Basin Facilities. The tests will mark the first time that large-scale tsunami tests will be conducted for US residential structures.

This project develops a collaboration with the Port and Airport Research Institute (PARI), Japan's premier research center for coastal infrastructure. Currently, the Tsunami and Storm Surge Division of PARI is developing a series of nested numerical models that can model tsunami propagation and inundation over a wide range of spatial scale, including tsunami forces on buildings.

This project will have an important educational aspect by training two graduate students, one at Oregon State and the other at Colorado State, and one undergraduate research student per year from Texas A&M University-Kingsville, a minority serving institution. This research will permeate to basic undergraduate and graduate engineering courses at OSU, CSU, and TAMU-Kingsville to increase awareness of the engineer?s role and responsibility in the design of houses and buildings exposed to the forces of nature.

Outreach aspects of this project will also focus on the use of technology to enhance learning via a hands-on design project related to tsunami-structure interaction for first year engineering students at universities outside the NEES@OSU site. In addition to this activity, the project as a whole will reach the general public through collaborations with two nationally known Museums of Science and Industry: one in Portland, OR, and the other in Chicago, IL. The project team will help the Chicago museum develop tsunami content for Science Storms, a high-visibility, marquee exhibit at the Museum, which welcomes over 1.5 million visitors, students, parents and teachers each year. The team will work with the Oregon museum on communicating the importance of engineering research to the general public. The project also supports one science teacher on the use of technology to enhance the learning of STEM subjects.

Data from this project will be made available through the NEES data repository (www.nees.org)

Project Report

The US tsunami evacuation strategy puts large populations at high risk to nearfield tsunamis because it requires that everyone evacuate the inundation zone and does not consider the possibility of vertical evacuation within the zone. Part of our unwillingness to adopt vertical evacuation strategies stems from an inability to estimate the damage level in the inundation area for a range of building types, including reinforced concrete (modern hotel), unreinforced concrete masonry units (older motel, light commercial) and light-frame wood (mostly residential and some commercial) structures. The long term objective of this research is to reduce loss of life and increase community resilience in the event of a tsunami by understanding the forces by tsunami on buildings, seawalls, and other structures near the shore. This project used the Network for Earthquake Engineering Simulation (NEES) Tsunami Research Facility to conduct two large-scale tsunami experiments. In the first set of experiment, we used the 100 m long wave channel to simulate the tsunami forces on vertical walls to understand how the force and pressure distribution on walls when they are hit by a tsunami, and we also looked at how smaller seawalls can be used to reduce the forces on these walls. We used the results of these tests to design new experimental procedures to replicate tsunami forces using hydraulic actuators in structures laboratories. We also used the results to develop new software modules that enable engineers to design structures to withstand tsunami forces. In the second set of experiments, we used the wider Tsunami Wave Basin to conduct tests to understand the three-dimensional effects of tsunami forces on structures. For these tests, we looked at a community of buildings to see how the layout of neighboring building can influence the forces on adjacent structures. In many case, neighboring buildings were shown to have an overall sheltering effect. However, we found unexpectedly in some cases that the neighboring building increased the forces on adjacent structures. This information can be used by planners to determine potential increased risk in tsunami inundation zones. In terms of broader impact, the researchers on this project have been working with the American Society of Civil Engineers to help develop new construction standards for essential facilities in tsunami zones. These new codes make use of the understanding developed in this project. In addition to improving engineering practice, this project has improved engineering education. Notably, the researchers in the project have worked with the Chicago Museum of Science and Industry to develop a tsunami display. The display consists of a large tsunami wave channel and a large screen projection display with content taken from the experiments and interviews conducted at the Tsunami Facility. The exhibit is viewed by approximately one million people per year.

Project Start
Project End
Budget Start
2008-10-01
Budget End
2012-09-30
Support Year
Fiscal Year
2008
Total Cost
$438,805
Indirect Cost
Name
Oregon State University
Department
Type
DUNS #
City
Corvallis
State
OR
Country
United States
Zip Code
97331