Transportation Commons^™

Functionality Risk Assessment And Risk-Based Management For Critical Infrastructure Systems, Anteneh Zewdu Deriba

Dissertations and Theses

Critical infrastructure systems such as transportation networks serve as the lifelines of modern society, supporting economic activity and ensuring access to critical services. Their disruption under extreme events can produce consequences extending far beyond physical damage to individual assets. In transportation networks for instance, failures of critical assets such as bridges and tunnels can reduce accessibility of communities, limit freight capabilities for commerce, and increase travel distance and travel time of road users. These consequences associated with the system functionality loss are tied not only to the physical vulnerability and failure of individual assets, but also to the system configuration …

Acceptance Of Shared Autonomous Vehicles: Exploring The Attitudes And Perspectives Of Older Adults, Sara Sohaee Urbina

Dissertations and Theses

The fast development of autonomous vehicle systems will create major changes in how people move around. Previous research shows that these technologies can benefit older people who struggle with mobility, safety and access to transportation. Shared Autonomous Vehicles (SAVs) enable older people to achieve self-reliance while obtaining essential services which enhance their quality of living. The successful deployment of SAVs requires users to accept this new technology which they must also be willing to use. This research study investigates which elements affect older adults to adopt SAVs by using an extended Technology Acceptance Model (TAM) framework.

The research design of …

Expanding Transmobilities: Understanding Genderdiverse And Transgender Travel Behavior Through An Art-Informed Methodology, Nicholas Michael Puczkowskyj

Dissertations and Theses

Transgender and genderdiverse people face discrimination and harassment in public when making trips in Portland, OR. People who identify as genderdiverse or transgender create unique travel behavior due to the influence of their internalized and expressed gender identity and through interactions in public. This dissertation examines how gender identity influences the travel behavior of genderdiverse and transgender people and how these experiences influence their subjective wellbeing when making trips in Portland, Oregon. Traditional one-on-one interviews were conducted in conjunction with allowing the interviewees to produce art as a non-verbal form of expression and communication of their experiences making trips in …

Evaluating The Impact Of Leading Pedestrian Intervals And Curb Extensions On Conflict Frequency And Severity, Sophia Semensky

Dissertations and Theses

Leading Pedestrian Intervals (LPIs) and curb extensions are commonly implemented countermeasures intended to improve pedestrian safety at signalized intersections. While LPIs have a well-established crash reduction record, fewer studies have evaluated their impacts using surrogate safety measures or examined how curb extensions interact with LPIs to influence pedestrian-vehicle conflicts. This thesis investigates the effects of LPIs and curb extensions on pedestrian safety using detailed conflict data collected at eleven signalized intersections in the Portland, Oregon metropolitan area.

Approximately 600 hours of video data were collected across four matched intersection pairs and three before–after sites. Pedestrian and vehicular volumes, turning speeds, …

An Integrated Multivariate Econometric Modeling Framework For Risky Driving Behavior Related Crashes: Evaluating Crash Risk And Severity Across Zones, Pabitra Kumar Roy

Dissertations and Theses

Rapid advancements in crash modeling have yet to fully integrate multiple behavior-driven crash types and their severity outcomes within a single, scalable framework, specially in a way that captures the sequential nature of these behaviors where one risky action may amplify another. This study proposed an integrated multivariate econometric framework to jointly model crash frequency and severity outcomes for three major behaviorally driven crash types: alcohol-related, distraction-related, and aggressive-driving-related crashes. Specifically, using Oregon's 2022 census block group-level crash data, we propose an Integrated Multivariate Negative Binomial – Generalized Ordered Probit Fractional Split (IMNB–GOPFS) model to analyze these dimensions simultaneously while …

Building Oregon's Statewide Multimodal Transportation Inventory With Ai And Interagency Collaboration, Ben Stabler, Theresa Conley

PSU Transportation Seminars

ODOT and 48+ local agencies are collaborating on the development of a multimodal data set for transportation planning within metropolitan areas. Revisions to Oregon's Transportation Planning Rules (TPR) set in motion the need for more multimodal data and analysis in local plans. The multimodal data inventory includes vehicle and freight facilities, bicycle and pedestrian facilities, transit facilities, and other relevant data such as key destinations and crashes. Starting from the local agency GIS systems and supplemented with real world use of AI for developing bicycle and pedestrian facilities, the team is defining and constructing a shared statewide multimodal data set. …

Reducing Motor Vehicle – Bicycle Conflicts At Controlled Intersections, Jason C. Anderson, Sirisha Kothuri

PSU Transportation Seminars

One of the most common locations for fatal motor vehicle-bicyclist crashes is at intersections, which inherently have a large number of turning conflicts. Reducing these conflicts is a key objective in improving intersection safety across all modes. Of particular concern for bicyclists’ safety at intersections are the conflicts between straight-through bicyclists and motor vehicle right-turns and opposing left-turns. The objective of this research was to develop guidance and tools for transportation practitioners to use to reduce turning conflicts between motor vehicles and bicycles at controlled intersections and improve the safety and comfort of intersections for bicyclists.

The Realities Of Roadkill: Challenges And Opportunities For Wildlife Transportation Mitigation, Rachel Wheat

PSU Transportation Seminars

Transportation infrastructure is critical for our communities and economies, but the roadways we depend on for travel have significant negative impacts on wildlife populations. Roadkill is the most visible consequence, with tens of millions of animals injured or killed on Oregon’s roadways each year. Beyond direct mortality, transportation corridors fragment habitat and can alter wildlife behavior, creating barriers that disrupt wildlife movement and access to critical resources, contributing to population declines. Despite these challenges, opportunities exist for mitigation, including the use of wildlife crossing structures, autonomous animal detection systems, and smarter project siting. This talk will explore the multifaceted challenges …

Transit-Oriented Development And Affordable Housing: Lessons From Portland, Nathan Mcneil

PSU Transportation Seminars

The seminar will cover surveys of residents at recently built Transit-Oriented Developments (TODs) focused on affordable housing sites. This study builds off of an ongoing partnership between Portland State University and the Portland Metro regional government to understand the travel choices of people who move to recently constructed Metro supported TODs. Since 2018, Metro has focused their TOD investment on affordable housing; this survey, conducted in 2024, offers a lens into how TOD works for these low-income Portlanders, how their travel differs from prior TOD residents, and what opportunities exist to improve the TOD - affordable housing combination.

Walk Portland: A Downtown Pedestrian Wayfinding Strategy And Pilot, Gena Gastaldi, Gwen Sullivan, Ryan Sullivan

PSU Transportation Seminars

Walk Portland, a partnership between the Portland Bureau of Transportation (PBOT) and Travel Portland, seeks to make it easier than ever for pedestrians to explore the city. In 2024, PBOT and Travel Portland, in partnership with sparks+sullivan, teamed up to develop a wayfinding strategic plan. In 2025, with grant funding from Travel Oregon, the team launched a short-term pilot wayfinding system to help people explore Portland as a pedestrian: the Downtown Portland Walking Route. The pilot, up from August-October 2025, is designed to see what works and what doesn’t in helping people navigate downtown. The long-term goal of this project …

Changing Minds, Changing Modes: Optimizing Public Perception Strategies For Urban Cycling Through Behavior Change Theory, Brandon Barnhart

University Honors Theses

This thesis addresses the recent decline in bicycle mode share in cities like Portland, Oregon, despite decades of investment in cycling infrastructure. While the "build it, and they will come" approach succeeded through the early 2000s, it no longer meets targets for bicycle use or broader goals related to sustainability, congestion, health, and safety. A new approach is needed that effectively rebuilds the cultural and behavioral components of cycling. This research asks: What role can behavior change theory play in increasing the effectiveness of public perception campaigns to promote urban cycling? Using a qualitative methodology, this study draws on behavior …

Is Ride-Hailing A Potential Solution For Older Adults After Driving Cessation? The Role Of Objective And Perceived Accessibility, Minju Kim Song

Dissertations and Theses

Due to age-related physical and cognitive changes, older drivers have a greater risk of crashes and are restricted by age-dependent regulation. Nonetheless, many older adults in the United States maintain a car-dependent lifestyle and still prefer driving. When driving cessation or reduction becomes necessary, a primary concern is finding suitable alternative transportation modes. However, the availability of alternative transportation modes does not guarantee their actual use of these options.

As a relatively new transportation mode, ride-hailing services, such as Uber and Lyft, offer on-demand, door-to-door transportation and may be a feasible transportation solution for older adults who stop driving. While …

Geography Of Non-Daytime Work And Employer-Centered Transit Accessibility, Julia Mai Plotts

Dissertations and Theses

Non-daytime shift workers--including those on evening, night, rotating, and split shifts--face unique transportation challenges. Those who rely on public transit often contend with complicated commutes and longer wait times on public transit systems that have traditionally catered to the 9-to-5 workforce. Meanwhile, the non-daytime workforce is disproportionately composed of marginalized groups, including low-income workers, racial and ethnic minorities, and individuals with fewer education credentials. For many lower-income workers, car ownership does not present a viable alternative, as cost-of-ownership consumes a significant portion of their income. This makes access to nighttime public transit a critical equity concern. However, most transit accessibility …

Accessible Bike Map Design: A Review And Critique Of Portland’S Bike Maps, Zachary Cheyney

Geography Masters Research Papers

Urban bike maps can serve as key tools for route planning and navigation for prospective cyclists, providing both general information (such as landmarks and natural features) and cycling specific information (such as bike lane infrastructure types and cycling amenities). Despite this, there is little professional guidance or academic research on best practices for bike map design. Potential guidance should consider the full range of potential cyclists, including disabled cyclists who have often been left out of cycling policy discussions. In this paper, I begin by discussing 3 case studies on participatory mapping methodologies with disabled participants in order to generate …

Active Transportation Data Fusion: Incorporating Big Data To Estimate Volumes, Joeseph Broach, Sirisha Kothuri, Nathan Mcneil

PSU Transportation Seminars

Planners and decision-makers have increasingly voiced a need for network-wide estimates of bicycling and walking. Such volume estimates have for decades informed motorized planning and analysis but have only recently become feasible for non-motorized travel modes. Recently, new sources of activity data have emerged derived primarily from GPS-based smartphone location data, both app-based and passively collected. The project team has led several research projects aimed at evaluating and integrating the emerging sources with conventional demand data, including observed bicycle and pedestrian counts, to assess the value added of various emerging sources and the potential for estimating network-wide volumes. This presentation …

Preventing Carbon Emissions With Imaging-Based Civil Infrastructure Assessment And Evaluation, Thomas Schumacher

PSU Transportation Seminars

For concrete bridges without existing plans, simplified and highly conservative load rating (structural evaluation) methods may be used, which can lead to unnecessary load restrictions, unjustifiable strengthening, or in the worst case, preventable replacements. Avoiding these outcomes not only saves money but it prevents carbon emissions from longer travel and construction activities and resources associated with replacement.

This presentation discusses a case study of a prestressed concrete bridge that required a load rating, and for which no plans existed. Imaging and image fusion using radar and ultrasonic measurements taken from the top and bottom of the slab were performed to …

Whipped Into Shape: Infrastructure As Punishment For The Unruly Citizen, Eliza Mortimer

Anthós

This article interrogates how inflexible designs and policies of airline seating, as well as critical socio-political rhetoric, discipline and marginalize bodies that do not conform to normative standards. Situating airline seating within fat and disability studies models, Mortimer argues that these punitive measures are not neutral, but rather reflective of cultural narratives of productivity, morality, and bodily discipline. Mortimer draws from ethnographic analyses of first-person accounts and policy reviews to demonstrate how shrinking seats, rigid policies, and moralized discourse construct a “space of calculability” that pressures fat individuals to monitor and minimize their bodies to justify their presence in public …

Piloting A Zero-Emission Delivery Zone In Downtown Portland, Art Pearce, Sarah Pullman, Jacob Sherman

PSU Transportation Seminars

The Portland Bureau of Transportation (PBOT) was awarded a nearly $2 million Strengthening Mobility and Revolutionizing Transportation (SMART) Grant by the US Department of Transportation (USDOT) in Fall 2023 to pilot the country’s first regulated Zero-Emission Delivery Zone in downtown Portland and test digital infrastructure tools. This project will test an innovative set of incentives and regulations to better understand what technology and strategies municipalities can use to support and reduce greenhouse gas emissions in the freight sector.

While other cities in the United States have piloted voluntary Zero-Emission Delivery Zones (ZEDZs) to encourage the transition of commercial fleets to …

Ev Charging At Multifamily Properties: Moving Beyond Barriers, Whit Jamieson, Anna Guida, Connor Herman

PSU Transportation Seminars

Transportation is the top contributor of greenhouse gas emissions in the US and light-duty vehicles are the #1 contributor to transportation emissions. Mass adoption of electric vehicles (EVs) is key in the fight toward a more sustainable future, but there are several factors that have delayed our transition to EVs.

EV charging at home is the most convenient and cost-effective charging option for EV drivers, but people living in multifamily housing face serious barriers to accessing home charging. During this session, we will explore why EV charging at multifamily housing is critical to mass adoption of EVs, barriers to charging …

Bike Buses: An Evaluation Of An Emerging Active Transportation To School Intervention, Evan Howington, Nathan Mcneil, John Macarthur

TREC Faculty and Staff Publications

Bike buses are a relatively new form of active transportation to school (ATS) that have primarily emerged in Europe and the United States. A form of coordinated, group bike riding along a defined route to school, bike buses are an outgrowth of Safe Routes to School interventions in North America that seek to reverse the declining rates of walking and biking to school among children. Our initial phase of research included a literature review of social and environmental factors affecting ATS in the contemporary North American context, and two convenience surveys of bike bus coordinators and parent participants. This initial …

Addressing Transportation Emissions Through State Climate And Energy Policy, Amy Schlusser

PSU Transportation Seminars

Oregon has adopted policies to reduce greenhouse gas emissions from the energy and transportation sectors. This presentation will provide some background on these policy frameworks and explore how these policies impact transportation fuels and the transportation sector more broadly.

Fast-Tracking Transit: Unveiling Portland's First Bus Rapid Transit Line And Signal Optimization Strategies, Mark Haines, Jesse Stemmler

PSU Transportation Seminars

This presentation on the Division Transit Project will provide an overview of the project elements including roadway design, bus station design, traffic signal timing and operations and the Next Gen Transit Signal Priority (TSP) system. We will discuss some lessons learned and provide before and after results from the project.

Let Knowledge Serve The City! A Decade Of Better Block Psu Projects, Ryan Hashagen

PSU Transportation Seminars

Better Block PSU works with Planning and Civil Engineering students to bring community ideas to life! Over the last 10 years, the pathway has resulted in many real world pop ups and capital projects implemented by volunteers and PBOT.

Bike Buses: An Evaluation Of An Emerging Active Transportation To School Intervention, Evan Howington, John H. Macarthur, Nathan W. Mcneil

PSU Transportation Seminars

Bike Buses are a relatively new form of Active Transportation to School (ATS) that have gained popularity in Europe and the United States in recent years. Generally, a bike bus consists of one or more adult supervisors, often parents, who guide a group of students along a defined ‘route’ to one or more schools. Using literature from the last 15 years published on ATS in North America, we identify four thematic areas of influence on Bike Buses: school policies, parent and student attitudes and behaviors, the urban environment, and the street environment. We conclude that Bike Buses can be situated …

Exploring Determinants Of Transit Recovery After The Covid-19 Pandemic, Udit Khandelwal

Dissertations and Theses

The COVID-19 pandemic significantly disrupted public transit systems across the US, resulting in substantial declines in ridership and revenue. At the same time, ridership has increased to different levels in cities. This thesis explores the determinants of transit recovery in American cities post-pandemic. It analyzes data from the National Transit Database (NTD) and employs a two-stage least squares (2SLS) regression model first laid out by Taylor et al. (2008) for data from 2000. Similar to the results of that paper, the thesis finds strong correlation between transit ridership and variables for transit supply and urban and demographic characteristics for 2019 …

Ghg Inventory From Building Washington State Department Of Transportation Roadways, Milad Ashtiani

PSU Transportation Seminars

State departments of transportation (DOTs) are increasingly focusing on reducing greenhouse gas (GHG) emissions, especially with new regulations like the Buy Clean Acts in California, Oregon, and Washington. This project, in collaboration with the Washington State Department of Transportation (WSDOT), aims to assess the agency's carbon emissions through a life cycle assessment of construction materials such as cement, concrete, steel, and asphalt, which are now under heightened scrutiny.

While WSDOT has already implemented strategies to reduce Scope 1 and Scope 2 emissions (related to direct and energy-related activities), there has been limited focus on Scope 3 emissions—those generated upstream in …

The Impacts Of A Multimodal Safety Project On North Lombard Street In Portland, Oregon, Jason Anderson

PSU Transportation Seminars

North Lombard Street/US-30 Bypass is a critical corridor in North Portland, serving both commercial and residential interests. This corridor is also ranked 11th in terms of fatal and serious injury crashes in Portland. The Oregon Department of Transportation and the Portland Bureau of Transportation undertook a reconfiguration to improve multimodal safety and accessibility for all users. The reconfiguration happened between North Fiske Ave and North Boston Ave. Improvements included additional curb ramps that meet ADA standards, safer crosswalks with fewer lanes to cross, buffered bike lanes, new pavement and center turn lanes, traffic signals, and RRFBs and median refuge islands. …

Transportation Decarbonization: A State Perspective, Tara Weidner

PSU Transportation Seminars

Oregon continues to be a leader in Transportation Decarbonization efforts nationally. The webinar will outline the state’s transportation GHG reduction roadmap, developed in 2012 to tackle legislatively mandated GHG reduction goals, with associated GHG targets for the state’s 8 metropolitan areas. Learn how this north star has guided our collective efforts within the state. How monitoring and new initiatives and regulations have kept us on course to these ambitious goals. And what actions remain to close the gap, both systematic changes at state and local levels, as well as individual choices by private firms and households. Actions that will both …

Understanding Travel Behavior And Accessibility For Older Adults: A Comprehensive Framework, Andy Hong, Cathy Liu, Ja Young Kim, Zihao Wen

TREC Final Reports

This study used a mixed-method design to examine travel behavior and accessibility of older adults. The research team conducted a statewide survey and focus groups to gather travel behavior data of older adults (50+) residing in Utah. The study also employed a two-step floating catchment area method, a novel spatial technique, and integrated the survey data to accurately measure travel accessibility of older adults. Using the survey data of 724 older adults as well as the focus group interviews of 18 older individuals, we found a significant dissatisfaction and vulnerability experienced by older adults with limited mobility. The distribution patterns …

Webinar: Building Capacity In Gateway Communities Through The Gnar Academy, Jordan Katcher, Elizabeth Sodja

TREC Webinar Series

Small towns and cities near national parks, public lands, and other natural amenities across the West are experiencing rapid growth and increased tourism. As we have documented via our prior NITC-funded research, this has created a range of big city challenges for these “gateway communities,” particularly in the form of interconnected transportation, land use, and housing issues. Seeking to help gateway communities better prepare for and respond to their transportation and planning challenges, the Gateway and Natural Amenity Region (GNAR) Initiative team translated the findings from our research on planning and development challenges in gateway communities into an online learning …