Before I discuss the details of the recent field work I completed in Christchurch, New Zealand, I will give a little background about myself. I grew up in Hillsboro, Oregon and have lived in Oregon my entire life. It made sense to attend Oregon State University as I was aspiring to become a Civil Engineer. After completing my Honors Bachelor of Science degree in Civil Engineering at Oregon State, I decided to continue my academic education and pursue a Master of Science degree in Structural Engineering.
Given the interdisciplinary nature of my research project, I have two current advisors, Michael Olsen (Civil Engineering Geomatics) and Andre Barbosa (Structural Engineering). Because my research deals with structural assessments in emergency situations, Michael Olsen invited me to participate on a NSF-funded research project in New Zealand evaluating houses damaged by rockfalls during earthquakes. He felt it would be helpful for me to see these damages firsthand.
The primary goal of the research project was to gather 3D, ground-based lidar (GBL) scans and structure from motion (SfM) photographs of the damage to houses resulting from rockfalls caused by the 2010-2011 Canterbury earthquakes. What made the trip to New Zealand interesting was the fact that I was primarily going to be doing geomatics field work despite the fact that my background was in structures. It wasnt until beginning our first day of field work that I entirely understood what we would be doing and how the process worked. Fortunately, Dr. Olsen and another geomatics graduate student (Matt OBanion) were there to help train me.
Being that it was winter in New Zealand, our typical day of field work started around 7:30 AM and would go until 5:30 PM when it was dark. Much of the evening was then spent backing up and processing data collected. One of the biggest realizations we had upon arriving at the houses was the condition they were in. Most of the houses we scanned havent been touched in over 3 years. Many of them still had family items inside. We also found that a large amount of vegetation began to grow over and around these houses. This made finding suitable scan positions a little more difficult than we thought. Upon arriving at these houses, we began by examining all the rock impacts, establishing scan positions, placing targets, and clearing away vegetation. In addition to the scanner, we brought additional equipment such as a total station and GNSS receiver for geo-referencing the scans.
My prior surveying experience consisted of only using the total station during a surveying course I took my junior year of college, approximately two years ago. Naturally, in the beginning I felt out of place and wondering how I could possibly be of help when I had little background with all the equipment. But as the scanning went on, I found myself growing familiar with the jargon, the scanner, and the vision of the project. Despite being one of the most advanced and sophisticated pieces of equipment I have ever used, I found the lidar scanner to be relatively easy and straightforward to use. The real challenge came with figuring out where to put the scanner to best capture the damages both inside and outside the house. In particular, we had to be very clever in where we placed targets due to line of sight constraints from debris and around tight corners.
I have never before found myself in a position such as this to perform field work for a research project, let alone with a geomatics background. However, I found the experience of using the scanner in the field to be rewarding. Upon seeing the rendered scans uploaded on the computer, I began to see just how powerful this equipment was. The houses themselves will be demolished soon, but because of this research project, we will have a 3D environment of these houses forever. This insight is invaluable because it will allow researchers and engineers to examine the impacts of rockfalls on houses with unprecedented detail. The data can be used by structural, geotechnical, and geomatics personnel to fully understand the impacts and hazards resulting from this damaging earthquake and resulting rockfalls.
Needless to say, my trip to New Zealand was fulfilling and impactful. The work we performed there is permanently recorded and can be of use in the future to avoid further damages resulting from rockfalls. As far as looking back and thinking of things I wish I knew before, Im not sure there is any. I would have liked to have a little more background with the equipment, but ultimately it was working in the field that taught me everything I needed to know. It is truly one of the most impactful experiences I have had in my life and it exposed me to the important role that geomatics has within civil engineering that I never knew before.
Acknowledgments:
This material is based upon work supported by the National Science Foundation under Grant No. CMMI-1439773 and CMMI-1439883. This work is being done in collaboration between the University of Washington and Oregon State University with Joseph Wartman (UW) as the Primary Principal Investigator. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. I would like to personally thank Dr. Michael Olsen (OSU) for giving me this opportunity. I also thank Leica Geosystems and David Evans and Associates for providing equipment and software used for this study.