TREC research addresses complex transportation problems by drawing on multiple disciplines, including engineering, planning, economics and design, from across the Portland State University campus. Use the search box at right to search for a specific project.
Research Highlights
The Use of Mt. Mazama Volcanic Ash as Natural Pozzolans for Sustainable Soil and Unpaved Road Improvement
Matthew Sleep
This Small Starts study offers sustainable road building materials for rural infrastructure, from an unlikely source. Approximately 7,000 years ago, the eruption of Oregon's Mt. Mazama blanketed the Klamath Basin region with a thick layer of volcanic ash. Matthew Sleep, an associate professor of civil engineering at Oregon Tech, investigated the use of this ash as a natural pozzolan for soil stabilization and unpaved roadway improvement. He found that the ash, prevalent in Southern Oregon, has…
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Statistical Inference for Multimodal Travel Time Reliability
Avinash Unnikrishnan Miguel Andres Figliozzi , Subhash Kochar
Travel time reliability – or the consistency and dependability of travel times from day to day, and at different times of day – is a key metric that significantly affects people’s travel behavior. Since businesses rely heavily on transportation systems, an unreliable transportation network can also impact the economic competitiveness of urban areas. As such, reliable travel times are important for transportation agencies to promote economic stability within a community. Having accurate methods…
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