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• 1. [Article] The Effects of Frequency of Social Interaction, Social Cohesion, Age, and the Built Environment on Walking

  The purpose of this dissertation was to explore, through a social ecological framework, the multifaceted effects of the neighborhood environment by investigating how dimensions of both the built environment ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Frequency of Social Interaction, Social Cohesion, Age, and the Built Environment on Walking Author: Luhr, Gretchen Allison Year: 2016 The purpose of this dissertation was to explore, through a social ecological framework, the multifaceted effects of the neighborhood environment by investigating how dimensions of both the built environment and the neighborhood social context may interact to influence walking. Aesthetics, land use mix, crime, and pedestrian infrastructure were considered with respect to built environment walkability, and the neighborhood social context was conceptualized using measures of both social cohesion and social interaction with neighbors. This research used data from an Environmental Protection Agency (EPA)-funded study of 748 adults (18 years of age and older) residing in the Lents neighborhood in Portland, Oregon. Through a series of both multiple linear and logistic regression models, the analyses examined the specific pathways by which social interaction with neighbors, social cohesion, and age influenced the relationship between the built environment and walking behavior. Results suggest that both social interaction and social cohesion but not age moderate the effects of the built environment on walking. There was evidence of mediation, as well, for both social interaction and social cohesion. The implications of these findings for future research and policy are discussed. Title: The Effects of Frequency of Social Interaction, Social Cohesion, Age, and the Built Environment on Walking Author: Luhr, Gretchen Allison Year: 2016 The purpose of this dissertation was to explore, through a social ecological framework, the multifaceted effects of the neighborhood environment by investigating how dimensions of both the built environment and the neighborhood social context may interact to influence walking. Aesthetics, land use mix, crime, and pedestrian infrastructure were considered with respect to built environment walkability, and the neighborhood social context was conceptualized using measures of both social cohesion and social interaction with neighbors. This research used data from an Environmental Protection Agency (EPA)-funded study of 748 adults (18 years of age and older) residing in the Lents neighborhood in Portland, Oregon. Through a series of both multiple linear and logistic regression models, the analyses examined the specific pathways by which social interaction with neighbors, social cohesion, and age influenced the relationship between the built environment and walking behavior. Results suggest that both social interaction and social cohesion but not age moderate the effects of the built environment on walking. There was evidence of mediation, as well, for both social interaction and social cohesion. The implications of these findings for future research and policy are discussed. Close

• 2. [Article] Transit Planning Practice in the Age of Transit-Oriented Development

  Transit serves as backbone infrastructure for many regional and local visions for sustainable urban development. Also, many modern policies predicate transit funding on the potential for transit-oriented ...

  Citation × Citation Citation Abstract Copy Title: Transit Planning Practice in the Age of Transit-Oriented Development Author: Carlton, Ian Year: 2014 Transit serves as backbone infrastructure for many regional and local visions for sustainable urban development. Also, many modern policies predicate transit funding on the potential for transit-oriented development (TOD) near proposed infrastructure investments. However, little research has examined how TOD considerations have informed transit planning. This presentation discusses the results of recent dissertation research that fills this gap. Through multiple transit project case studies and interviews with nearly 100 transit planning professionals, this research categorized how transit projects across 19 U.S. regions were designed to foster TOD and how transit planning professionals identified TOD opportunities as projects were planned. During interviews, many professionals lamented the amount of real estate development that had occurred around the transit projects they helped plan. Analysis revealed that the ways in which professionals identified TOD opportunities helped to explain disconnects between their expectations and actual outcomes. The findings raise concerns about the effectiveness and efficiency of transit planning practice in the age of transit-oriented development and point to potential policy and practice changes that could address the issues. Title: Transit Planning Practice in the Age of Transit-Oriented Development Author: Carlton, Ian Year: 2014 Transit serves as backbone infrastructure for many regional and local visions for sustainable urban development. Also, many modern policies predicate transit funding on the potential for transit-oriented development (TOD) near proposed infrastructure investments. However, little research has examined how TOD considerations have informed transit planning. This presentation discusses the results of recent dissertation research that fills this gap. Through multiple transit project case studies and interviews with nearly 100 transit planning professionals, this research categorized how transit projects across 19 U.S. regions were designed to foster TOD and how transit planning professionals identified TOD opportunities as projects were planned. During interviews, many professionals lamented the amount of real estate development that had occurred around the transit projects they helped plan. Analysis revealed that the ways in which professionals identified TOD opportunities helped to explain disconnects between their expectations and actual outcomes. The findings raise concerns about the effectiveness and efficiency of transit planning practice in the age of transit-oriented development and point to potential policy and practice changes that could address the issues. Close

• 3. [Article] Travel Behavior, Residential Preference, and Urban Design: A Multi-Disciplinary National Analysis

  This report summarizes the findings of a national project to examine the travel behavior, social capital, health, and lifestyle preferences of residents of neotraditional developments (NTD) compared to ...

  Citation × Citation Citation Abstract Copy Title: Travel Behavior, Residential Preference, and Urban Design: A Multi-Disciplinary National Analysis Author: Greene, Jessica, Larco, Nico, Yang, Yizhao, Schlossberg, Marc, Rodriguez, Daniel, McDonald, Noreen, Combs, Tabitha Year: 2011 This report summarizes the findings of a national project to examine the travel behavior, social capital, health, and lifestyle preferences of residents of neotraditional developments (NTD) compared to more standard suburban developments. We compare survey results from residents of matched pairs of neighborhoods in seventeen U.S. cities and towns, with each pair comprised of one NTD and one typical suburban neighborhood of similar size, age, and socio-demographic composition. The study addresses salient themes in the transportation, planning and health literatures: a national study, surveying populations of diverse incomes, collecting resident information on preferences for and attitudes towards neighborhood qualities, and addressing transportation and health outcomes for diverse community designs. Title: Travel Behavior, Residential Preference, and Urban Design: A Multi-Disciplinary National Analysis Author: Greene, Jessica, Larco, Nico, Yang, Yizhao, Schlossberg, Marc, Rodriguez, Daniel, McDonald, Noreen, Combs, Tabitha Year: 2011 This report summarizes the findings of a national project to examine the travel behavior, social capital, health, and lifestyle preferences of residents of neotraditional developments (NTD) compared to more standard suburban developments. We compare survey results from residents of matched pairs of neighborhoods in seventeen U.S. cities and towns, with each pair comprised of one NTD and one typical suburban neighborhood of similar size, age, and socio-demographic composition. The study addresses salient themes in the transportation, planning and health literatures: a national study, surveying populations of diverse incomes, collecting resident information on preferences for and attitudes towards neighborhood qualities, and addressing transportation and health outcomes for diverse community designs. Close

• 4. [Article] Performance Enhancement of Bridge Bracing Under Service and Extreme Loads

  As truck loads continue to get bigger, the demand on many aging bridges increases. Slender steel structural elements widely used in bridge superstructures and braced substructures to resist these loads ...

  Citation × Citation Citation Abstract Copy Title: Performance Enhancement of Bridge Bracing Under Service and Extreme Loads Author: Dusicka, Peter, Stephens, Max Taylor, Fox-Lent, Kate Year: 2010 As truck loads continue to get bigger, the demand on many aging bridges increases. Slender steel structural elements widely used in bridge superstructures and braced substructures to resist these loads are built primarily for tension, however, and can buckle under compressive loads. Portland State University associate professor Peter Dusicka set out to develop and demonstrate the concept of retrofitting bridge brace elements with fiber reinforced composites in order to provide restraint against buckling. The advanced materials consisted of a combination of fiber reinforced polymer (FRP) composite pultruded sections and wet lay-up wraps intended to be applied in the field. This exploratory study shows that retrofitting slender bracing members retrofitted with FRP sections improves performance. All retrofitted specimens showed an improved compressive strength in the linear elastic and plastic deformation range of the slender bracing member. The cyclic behavior exhibited only a marginal improvement, however, due to failure modes at the bolted connections of the brace; modifying the brace only slightly improved the cyclic performance. Despite the connection failures of the retrofitted members, the demonstration shows that the developed concept of applying fiber reinforced composites can keep slender bracing members from buckling and improve the compressive resistance. Further testing needs to be conducted to evaluate a better implementation to resist cyclic loads. Title: Performance Enhancement of Bridge Bracing Under Service and Extreme Loads Author: Dusicka, Peter, Stephens, Max Taylor, Fox-Lent, Kate Year: 2010 As truck loads continue to get bigger, the demand on many aging bridges increases. Slender steel structural elements widely used in bridge superstructures and braced substructures to resist these loads are built primarily for tension, however, and can buckle under compressive loads. Portland State University associate professor Peter Dusicka set out to develop and demonstrate the concept of retrofitting bridge brace elements with fiber reinforced composites in order to provide restraint against buckling. The advanced materials consisted of a combination of fiber reinforced polymer (FRP) composite pultruded sections and wet lay-up wraps intended to be applied in the field. This exploratory study shows that retrofitting slender bracing members retrofitted with FRP sections improves performance. All retrofitted specimens showed an improved compressive strength in the linear elastic and plastic deformation range of the slender bracing member. The cyclic behavior exhibited only a marginal improvement, however, due to failure modes at the bolted connections of the brace; modifying the brace only slightly improved the cyclic performance. Despite the connection failures of the retrofitted members, the demonstration shows that the developed concept of applying fiber reinforced composites can keep slender bracing members from buckling and improve the compressive resistance. Further testing needs to be conducted to evaluate a better implementation to resist cyclic loads. Close

• 5. [Article] Investigations In Transportation

  The Investigations in Transportation program is an elementary school partnership and curriculum development project that will engage science, technology, engineering and mathematics (STEM) professionals ...

  Citation × Citation Citation Abstract Copy Title: Investigations In Transportation Author: Becker, William G., Biskupic Knight, Carol Year: 2015 The Investigations in Transportation program is an elementary school partnership and curriculum development project that will engage science, technology, engineering and mathematics (STEM) professionals in school-based activities and projects that will bring real-world applications to elementary classrooms for grades 3-5. The Portland Metro STEM Partnership (PMSP) is providing leadership and facilitation to a team of educators from Portland State University, Beaverton School District and Hillsboro School District who will work with volunteers from the Oregon Department of Transportation (ODOT) to design, develop, implement and assess the impact of an in-class unit entitled "Investigations in Transportation". This report presents a study of a transportation education partnership and curriculum development project that harnessed the professional expertise, experience and enthusiasm of transportation-sector STEM workers by creating a mechanism and set of protocols by which they engaged with elementary school teachers to develop and implement an instructional unit. This STEM-connected instructional unit and lessons allowed students to explore and investigate issues central to transportation. The unit incorporated and enhanced the content and practice standards outlined by the Common Core State Standards and Next Generation Science Standards, and relied heavily on the instructional and curriculum expertise and experience of classroom teachers to develop an age- and interest-appropriate unit of study. This collaboration resulted in the development of an Investigations in Transportation instructional unit that provided students with rich, engaging learning opportunities set in the context of real-world problems around a school parking lot dilemma focused on safety, sustainability and health concerns. The education project team utilized a coherent and cohesive curriculum development process for unit creation and evaluated the development, implementation and reflection of the unit through teacher and student surveys/assessments of attitudes, identity and conceptual understanding. The report describes the process successes, challenges and replication opportunities. Title: Investigations In Transportation Author: Becker, William G., Biskupic Knight, Carol Year: 2015 The Investigations in Transportation program is an elementary school partnership and curriculum development project that will engage science, technology, engineering and mathematics (STEM) professionals in school-based activities and projects that will bring real-world applications to elementary classrooms for grades 3-5. The Portland Metro STEM Partnership (PMSP) is providing leadership and facilitation to a team of educators from Portland State University, Beaverton School District and Hillsboro School District who will work with volunteers from the Oregon Department of Transportation (ODOT) to design, develop, implement and assess the impact of an in-class unit entitled "Investigations in Transportation". This report presents a study of a transportation education partnership and curriculum development project that harnessed the professional expertise, experience and enthusiasm of transportation-sector STEM workers by creating a mechanism and set of protocols by which they engaged with elementary school teachers to develop and implement an instructional unit. This STEM-connected instructional unit and lessons allowed students to explore and investigate issues central to transportation. The unit incorporated and enhanced the content and practice standards outlined by the Common Core State Standards and Next Generation Science Standards, and relied heavily on the instructional and curriculum expertise and experience of classroom teachers to develop an age- and interest-appropriate unit of study. This collaboration resulted in the development of an Investigations in Transportation instructional unit that provided students with rich, engaging learning opportunities set in the context of real-world problems around a school parking lot dilemma focused on safety, sustainability and health concerns. The education project team utilized a coherent and cohesive curriculum development process for unit creation and evaluated the development, implementation and reflection of the unit through teacher and student surveys/assessments of attitudes, identity and conceptual understanding. The report describes the process successes, challenges and replication opportunities. Close

• 6. [Article] The Importance of Housing, Accessibility, and Transport Characteristic Ratings on Stated Neighborhood Preference

  Travel demand models commonly lack the ability to understand how changing residential preferences influence future housing, land use, and transportation policies. As communities struggle to address social ...

  Citation × Citation Citation Abstract Copy Title: The Importance of Housing, Accessibility, and Transport Characteristic Ratings on Stated Neighborhood Preference Author: Currans, Kristina Marie Year: 2016 Travel demand models commonly lack the ability to understand how changing residential preferences influence future housing, land use, and transportation policies. As communities struggle to address social challenges related to increased economic uncertainty, transportation and land use planning have become increasingly centered on assumptions concerning the market for residential environments and travel choices. In response, an added importance has been placed on the development of toolkits capable of providing robust and flexible models to aid in understanding how differing assumptions contribute to a set of planning scenarios and how future residential location decisions may be made. In this study, we aim to examine the ability for current land use and transportation models to adequately account for the mechanism that drive households to prefer different neighborhoods based on typical transportation modeling methods. In particular, we conduct an original stated preference survey to identify the characteristics and preferences of individuals and households that influence unconstrained residential neighborhood preferences. Our objectives are to (a) determine the key drivers of residential neighborhood preferences, (b) test the contribution of sociodemographic and economic household characteristics commonly used in regional modeling tools to allocate households regionally across neighborhoods (e.g. household size, income, age, tenure), and (c) identify the preference profiles that can improve the sensitivity of our regional and statewide transportation-land use models to residential neighborhood preferences. The presentation for this seminar was done jointly with Steven Gehrke. It can be accessed at http://archives.pdx.edu/ds/psu/18234. Title: The Importance of Housing, Accessibility, and Transport Characteristic Ratings on Stated Neighborhood Preference Author: Currans, Kristina Marie Year: 2016 Travel demand models commonly lack the ability to understand how changing residential preferences influence future housing, land use, and transportation policies. As communities struggle to address social challenges related to increased economic uncertainty, transportation and land use planning have become increasingly centered on assumptions concerning the market for residential environments and travel choices. In response, an added importance has been placed on the development of toolkits capable of providing robust and flexible models to aid in understanding how differing assumptions contribute to a set of planning scenarios and how future residential location decisions may be made. In this study, we aim to examine the ability for current land use and transportation models to adequately account for the mechanism that drive households to prefer different neighborhoods based on typical transportation modeling methods. In particular, we conduct an original stated preference survey to identify the characteristics and preferences of individuals and households that influence unconstrained residential neighborhood preferences. Our objectives are to (a) determine the key drivers of residential neighborhood preferences, (b) test the contribution of sociodemographic and economic household characteristics commonly used in regional modeling tools to allocate households regionally across neighborhoods (e.g. household size, income, age, tenure), and (c) identify the preference profiles that can improve the sensitivity of our regional and statewide transportation-land use models to residential neighborhood preferences. The presentation for this seminar was done jointly with Steven Gehrke. It can be accessed at http://archives.pdx.edu/ds/psu/18234. Close

• 7. [Article] Assessing Transit Fare Equity in Utah Using a Geographic Information System

  The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately ...

  Citation × Citation Citation Abstract Copy Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Close

• 8. [Article] Do TODs Make a Difference?

  In this report, we present research that measures the outcomes of TOD areas in relation to their metropolitan area controls with respect to (1) jobs by sector; (2) housing choice for household types based ...

  Citation × Citation Citation Abstract Copy Title: Do TODs Make a Difference? Author: Nelson, Arthur C., Miller, Matt, Eskic, Dejan, Kim, Keuntae, Ewing, Reid, Liu, Jenny H., Berggren, Matt, Mumuni, Zakari Year: 2015 In this report, we present research that measures the outcomes of TOD areas in relation to their metropolitan area controls with respect to (1) jobs by sector; (2) housing choice for household types based on key demographic characteristics; (3) housing affordability based on transportation costs; and (4) job-worker balance as a measure of accessibility. Prior literature has not systematically evaluated TOD outcomes in these respects with respect to light rail transit (LRT), commuter rail transit (CRT), bus rapid transit (BRT), and streetcar transit (SCT) systems. Our analysis helps close some of these gaps. We apply our analysis to 23 fixed-guideway transit systems operating in 17 metropolitan areas in the South and West that have one or more of those systems. We find: (1) Most TOD areas gained jobs in the office, knowledge, education, health care and entertainment sectors, adding more than $100 billion in wages capitalized over time; (2) In assessing economic resilience associated with LRT systems, jobs continued to shift away from TOD areas before the Great Recession, the pace slowed during the recession but reversed during recovery, leading us to speculate that LRT TOD areas may have transformed metropolitan economies served by LRT systems; (3) Rents for offices, retail stores and apartments were higher when closer to SCT systems, had mixed results with respect LRT systems, but were mostly lower with respect to CRT systems (our BRT sample was too small to evaluate); (4) SCT systems performed best in terms of increasing their TOD-area shares of metropolitan population, households and householders by age, housing units, and renters with BRT systems performing less well while LRT and CRT systems experienced a much smaller shift in the share of growth; (5) Household transportation costs as a share of budgets increase with respect to distance from LRT transit stations to seven miles, suggesting the proximity to LRT stations reduces total household transportation costs; (6) Emerging trends that may favor higher-wage jobs locating in TOD areas over time than lower- or middle-wage jobs, perhaps because TOD areas attract more investment which requires more productive, higher-paid labor to justify the investment; and (7) The share of workers who commute 10 minutes or less to work increases nearly one-half of 1 percent for each half-mile their resident block group is to an LRT transit station, capping at a gain of 1.3 percent, which is not a trivial gain. Our report summarizes case studies of 23 transit systems and three journal articles based on our research. Title: Do TODs Make a Difference? Author: Nelson, Arthur C., Miller, Matt, Eskic, Dejan, Kim, Keuntae, Ewing, Reid, Liu, Jenny H., Berggren, Matt, Mumuni, Zakari Year: 2015 In this report, we present research that measures the outcomes of TOD areas in relation to their metropolitan area controls with respect to (1) jobs by sector; (2) housing choice for household types based on key demographic characteristics; (3) housing affordability based on transportation costs; and (4) job-worker balance as a measure of accessibility. Prior literature has not systematically evaluated TOD outcomes in these respects with respect to light rail transit (LRT), commuter rail transit (CRT), bus rapid transit (BRT), and streetcar transit (SCT) systems. Our analysis helps close some of these gaps. We apply our analysis to 23 fixed-guideway transit systems operating in 17 metropolitan areas in the South and West that have one or more of those systems. We find: (1) Most TOD areas gained jobs in the office, knowledge, education, health care and entertainment sectors, adding more than $100 billion in wages capitalized over time; (2) In assessing economic resilience associated with LRT systems, jobs continued to shift away from TOD areas before the Great Recession, the pace slowed during the recession but reversed during recovery, leading us to speculate that LRT TOD areas may have transformed metropolitan economies served by LRT systems; (3) Rents for offices, retail stores and apartments were higher when closer to SCT systems, had mixed results with respect LRT systems, but were mostly lower with respect to CRT systems (our BRT sample was too small to evaluate); (4) SCT systems performed best in terms of increasing their TOD-area shares of metropolitan population, households and householders by age, housing units, and renters with BRT systems performing less well while LRT and CRT systems experienced a much smaller shift in the share of growth; (5) Household transportation costs as a share of budgets increase with respect to distance from LRT transit stations to seven miles, suggesting the proximity to LRT stations reduces total household transportation costs; (6) Emerging trends that may favor higher-wage jobs locating in TOD areas over time than lower- or middle-wage jobs, perhaps because TOD areas attract more investment which requires more productive, higher-paid labor to justify the investment; and (7) The share of workers who commute 10 minutes or less to work increases nearly one-half of 1 percent for each half-mile their resident block group is to an LRT transit station, capping at a gain of 1.3 percent, which is not a trivial gain. Our report summarizes case studies of 23 transit systems and three journal articles based on our research. Close