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• 1. [Article] Dynamic Evaluation of Transportation Structures with iPod-Based Data Acquisition

  This grant supported coursework and laboratory development and expanded research capacity, promoting (a) innovative learning activities that expose students to cutting-edge methods of bridge structural ...

  Citation × Citation Citation Abstract Copy Title: Dynamic Evaluation of Transportation Structures with iPod-Based Data Acquisition Author: Riley, Charles Year: 2017 This grant supported coursework and laboratory development and expanded research capacity, promoting (a) innovative learning activities that expose students to cutting-edge methods of bridge structural health and behavior monitoring and (b) research by our growing group of graduate students using developing technologies (specifically, shake tables and iPods with on-board accelerometers). As transportation infrastructure reaches and exceeds its design life, engineering efforts are turning to evaluation, rehabilitation and repair. Accurately assessing structures to determine their future performance and remaining life is becoming a primary job function for many civil engineers. As part of this project, graduate students worked with the PI to develop course modules that employed iPods in the laboratory and classroom to introduce concepts of vibrations, dynamic evaluation methods, structural health monitoring, and damage detection. Learning gains as a result of the module were assessed with both direct and indirect methods. While learning gains appeared stronger for students who participated in the hands-on component of the laboratory, due to the small class size there were no statistically significant differences between using iPods in a hands-on laboratory versus a purely computational laboratory. However, students indicated that iPods and hands-on laboratories were their preferred experience. The team also investigated laboratory and field applications, as well as effectiveness, of iPods to study structural dynamics and structural health monitoring methods, specifically for area bridges and other transportation structures. Sensor networks and mobile device-based accelerometers are beginning to be recognized as a valid means for conducting structural evaluations. The equipment purchased with this grant allowed for a new laboratory to be developed at Oregon Tech to support multiple undergraduate and graduate elective courses including Bridge Rating, Bridge Design, Transportation Structures, and Structural Dynamics. The Structural Health and Kinetic Evaluation (SHAKE) Laboratory and the associated equipment will support education and research efforts at Oregon Tech well into the future. Title: Dynamic Evaluation of Transportation Structures with iPod-Based Data Acquisition Author: Riley, Charles Year: 2017 This grant supported coursework and laboratory development and expanded research capacity, promoting (a) innovative learning activities that expose students to cutting-edge methods of bridge structural health and behavior monitoring and (b) research by our growing group of graduate students using developing technologies (specifically, shake tables and iPods with on-board accelerometers). As transportation infrastructure reaches and exceeds its design life, engineering efforts are turning to evaluation, rehabilitation and repair. Accurately assessing structures to determine their future performance and remaining life is becoming a primary job function for many civil engineers. As part of this project, graduate students worked with the PI to develop course modules that employed iPods in the laboratory and classroom to introduce concepts of vibrations, dynamic evaluation methods, structural health monitoring, and damage detection. Learning gains as a result of the module were assessed with both direct and indirect methods. While learning gains appeared stronger for students who participated in the hands-on component of the laboratory, due to the small class size there were no statistically significant differences between using iPods in a hands-on laboratory versus a purely computational laboratory. However, students indicated that iPods and hands-on laboratories were their preferred experience. The team also investigated laboratory and field applications, as well as effectiveness, of iPods to study structural dynamics and structural health monitoring methods, specifically for area bridges and other transportation structures. Sensor networks and mobile device-based accelerometers are beginning to be recognized as a valid means for conducting structural evaluations. The equipment purchased with this grant allowed for a new laboratory to be developed at Oregon Tech to support multiple undergraduate and graduate elective courses including Bridge Rating, Bridge Design, Transportation Structures, and Structural Dynamics. The Structural Health and Kinetic Evaluation (SHAKE) Laboratory and the associated equipment will support education and research efforts at Oregon Tech well into the future. Close

• 2. [Article] Seismic Hazard Assessment of Oregon Highway Truck Routes

  This research project developed a seismic risk assessment model along the major truck routes in Oregon. The study had adopted federally developed software tools called Risk for Earthquake Damage to Roadway ...

  Citation × Citation Citation Abstract Copy Title: Seismic Hazard Assessment of Oregon Highway Truck Routes Author: Dusicka, Peter, Mehary, Selamawit Tesfayesus Year: 2012 This research project developed a seismic risk assessment model along the major truck routes in Oregon. The study had adopted federally developed software tools called Risk for Earthquake Damage to Roadway Systems (REDARS2) and HAZUS-MH. The model was the first time REDARS2 has been adopted and used in research outside of the original development team, presenting a number of unique challenges. The development of the model was a complex, intensive process that required a significant research effort, manipulation and adjustment of data. Furthermore, limitations of the software tools themselves had been identified that prevented the inclusion of important aspects such as liquefaction induced damage and refinement of the transportation network. The main objective of this research were to refine the data from a first generation of the model to more realistically represent the bridge inventory, to address the seismicity of the Pacific Northwest, conduct sensitivity analyses of soil data on the analyses results and develop a seismic network model of Oregon bridges for purposes of assessing the seismic vulnerability of roadway segments. The first generation model relied on default settings within the program to determine the economic loss due to repair and replacement of damaged bridges. The assumptions used in the analyses have been reviewed and Oregon specific data was incorporated for the model. The largest earthquake now considered to be at a highest level of probability in the Pacific Northwest is a subduction zone earthquake. The major shortcoming of REDARS2 is its inability to incorporate the subduction zone attenuation relationship into the analysis. To incorporate that capability into the model, shakemaps were developed by USGS for Cascadia subduction zone scenario events and incorporated as the demand on the refined model. Analyses of the transportation network incorporating bridge routes and post processing of the data with input from Oregon DOT bridge engineers resulted in recommendations toward bridge route priority strategies. The majority of the bridges that indicated the possibility of damage were types associated with multi-column bents, simply-supported concrete superstructures and simply-supported steel superstructures. Of the major highway routes that were considered, I-405, section of I-5 (from Multnomah to Clackamas Counties), I-84, I-205 and US-101 were the top five on the preliminary priority for seismic retrofit. These routes need to be analyzed more and advanced cost-benefit investigations should be done before retrofit decisions are made. Title: Seismic Hazard Assessment of Oregon Highway Truck Routes Author: Dusicka, Peter, Mehary, Selamawit Tesfayesus Year: 2012 This research project developed a seismic risk assessment model along the major truck routes in Oregon. The study had adopted federally developed software tools called Risk for Earthquake Damage to Roadway Systems (REDARS2) and HAZUS-MH. The model was the first time REDARS2 has been adopted and used in research outside of the original development team, presenting a number of unique challenges. The development of the model was a complex, intensive process that required a significant research effort, manipulation and adjustment of data. Furthermore, limitations of the software tools themselves had been identified that prevented the inclusion of important aspects such as liquefaction induced damage and refinement of the transportation network. The main objective of this research were to refine the data from a first generation of the model to more realistically represent the bridge inventory, to address the seismicity of the Pacific Northwest, conduct sensitivity analyses of soil data on the analyses results and develop a seismic network model of Oregon bridges for purposes of assessing the seismic vulnerability of roadway segments. The first generation model relied on default settings within the program to determine the economic loss due to repair and replacement of damaged bridges. The assumptions used in the analyses have been reviewed and Oregon specific data was incorporated for the model. The largest earthquake now considered to be at a highest level of probability in the Pacific Northwest is a subduction zone earthquake. The major shortcoming of REDARS2 is its inability to incorporate the subduction zone attenuation relationship into the analysis. To incorporate that capability into the model, shakemaps were developed by USGS for Cascadia subduction zone scenario events and incorporated as the demand on the refined model. Analyses of the transportation network incorporating bridge routes and post processing of the data with input from Oregon DOT bridge engineers resulted in recommendations toward bridge route priority strategies. The majority of the bridges that indicated the possibility of damage were types associated with multi-column bents, simply-supported concrete superstructures and simply-supported steel superstructures. Of the major highway routes that were considered, I-405, section of I-5 (from Multnomah to Clackamas Counties), I-84, I-205 and US-101 were the top five on the preliminary priority for seismic retrofit. These routes need to be analyzed more and advanced cost-benefit investigations should be done before retrofit decisions are made. Close

• 3. [Article] Multi-Criteria Trucking Freeway Performance Measures in Congested Corridors

  Research was undertaken to develop multicriteria tools for measuring and analyzing the impact of recurring and nonrecurring congestion on freight. Unlike previous studies, this work used several distinct ...

  Citation × Citation Citation Abstract Copy Title: Multi-Criteria Trucking Freeway Performance Measures in Congested Corridors Author: Figliozzi, Miguel, Wheeler, Nikki Year: 2011 Research was undertaken to develop multicriteria tools for measuring and analyzing the impact of recurring and nonrecurring congestion on freight. Unlike previous studies, this work used several distinct data sources to analyze the effects of congestion on I-5 in the Portland, Oregon, metropolitan area: Global Positioning System data from commercial trucks, Oregon Department of Transportation corridor travel time loop data, and incident data. A new methodology and algorithms combine these data sources and estimate the impact of recurrent and nonrecurrent congestion on reliability and delays, costs, and emissions of freight movements. The results suggest that traditional traffic sensor data tend to underestimate the impact of congestion on travel times and variability of commercial vehicles. Congestion is detrimental not only for carriers' and shippers' costs but also for the planet because of increases in greenhouse gas emissions and for the local community because of increases in oxides of nitrogen, particulate matter, and other harmful pollutants. The developed methodology can provide useful freight operation and performance data for the freight community, transportation decision makers, and other transportation stakeholders. For more information: http://archives.pdx.edu/ds/psu/11487 Title: Multi-Criteria Trucking Freeway Performance Measures in Congested Corridors Author: Figliozzi, Miguel, Wheeler, Nikki Year: 2011 Research was undertaken to develop multicriteria tools for measuring and analyzing the impact of recurring and nonrecurring congestion on freight. Unlike previous studies, this work used several distinct data sources to analyze the effects of congestion on I-5 in the Portland, Oregon, metropolitan area: Global Positioning System data from commercial trucks, Oregon Department of Transportation corridor travel time loop data, and incident data. A new methodology and algorithms combine these data sources and estimate the impact of recurrent and nonrecurrent congestion on reliability and delays, costs, and emissions of freight movements. The results suggest that traditional traffic sensor data tend to underestimate the impact of congestion on travel times and variability of commercial vehicles. Congestion is detrimental not only for carriers' and shippers' costs but also for the planet because of increases in greenhouse gas emissions and for the local community because of increases in oxides of nitrogen, particulate matter, and other harmful pollutants. The developed methodology can provide useful freight operation and performance data for the freight community, transportation decision makers, and other transportation stakeholders. For more information: http://archives.pdx.edu/ds/psu/11487 Close

• 4. [Article] Evaluating the Use of Crowdsourcing as a Data Collection Method for Bicycle Performance Measures and Identification of Facility Improvement Needs

  This research developed a smartphone application called ORcycle to collect cyclists’ routes, users, and comfort levels. ORcycle combines GPS revealed route data collection with new questionnaires that ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the Use of Crowdsourcing as a Data Collection Method for Bicycle Performance Measures and Identification of Facility Improvement Needs Author: Figliozzi, Miguel A., Blanc, Bryan Philip Year: 2015 This research developed a smartphone application called ORcycle to collect cyclists’ routes, users, and comfort levels. ORcycle combines GPS revealed route data collection with new questionnaires that try to elicit cyclists’ attitudes as well as comfort levels and factors that influence their perceived comfort and route choice. The new questionnaires were developed to better understand how cyclists’ comfort levels are affected by route characteristics, route stressors, safety reports, cyclists’ demographics, and cyclists’ cycling attitude. Preliminary results show that many trip characteristics, route choice factors, route stressors and demographic variables are correlated with comfort levels. ORcycle is the first statewide deployment of a smartphone application to collect bicycle specific safety and crash data in addition to travel and comfort data. Potential applications that can take advantage of the ORcycle data include: comfort and route models, prioritization of network improvements, and crash and injury risk models. Title: Evaluating the Use of Crowdsourcing as a Data Collection Method for Bicycle Performance Measures and Identification of Facility Improvement Needs Author: Figliozzi, Miguel A., Blanc, Bryan Philip Year: 2015 This research developed a smartphone application called ORcycle to collect cyclists’ routes, users, and comfort levels. ORcycle combines GPS revealed route data collection with new questionnaires that try to elicit cyclists’ attitudes as well as comfort levels and factors that influence their perceived comfort and route choice. The new questionnaires were developed to better understand how cyclists’ comfort levels are affected by route characteristics, route stressors, safety reports, cyclists’ demographics, and cyclists’ cycling attitude. Preliminary results show that many trip characteristics, route choice factors, route stressors and demographic variables are correlated with comfort levels. ORcycle is the first statewide deployment of a smartphone application to collect bicycle specific safety and crash data in addition to travel and comfort data. Potential applications that can take advantage of the ORcycle data include: comfort and route models, prioritization of network improvements, and crash and injury risk models. Close

• 5. [Article] Algorithms for Studying the Impact of Travel Time Reliability Along Multisegment Trucking Freight Corridors

  Performance measures allow planners and engineers to monitor and evaluate transportation facilities or projects and to justify the allocation of funds among alternative transportation improvement options. ...

  Citation × Citation Citation Abstract Copy Title: Algorithms for Studying the Impact of Travel Time Reliability Along Multisegment Trucking Freight Corridors Author: Figliozzi, Miguel, Wheeler, Nikki, Albright, Eric, Walker, Lindsay, Sarkar, Shreemoyee, Rice, Danielle Year: 2011 Performance measures allow planners and engineers to monitor and evaluate transportation facilities or projects and to justify the allocation of funds among alternative transportation improvement options. To capture the impact of corridor congestion on freight vehicles, new tools and methodologies are developed to analyze data from commercial vehicles and produce performance measures such as travel time, speed, and travel time reliability. Because long freight corridors comprise segments with varying reliability characteristics, the objective was to develop a programming logic that would use available truck Global Positioning System data to (a) identify natural segments or regions in a corridor between urban centers, Interstate junctions, or rural areas and (b) estimate corridorwide impact of travel time unreliability. The case study presented investigates the I-5 corridor in Oregon. The research applies statistical techniques to compute vehicle travel time and reliability for freight movements within each segment. The proposed methodology has been used successfully to identify distinct segments and characteristics of travel time reliability in freight corridors. Travel time information was used to compute cost effects of delays within rural and urban areas along the I-5 corridor. The research presents an advance in the processing and aggregation of Global Positioning System truck data to produce succinct yet informative performance measures and segments. For more information: http://archives.pdx.edu/ds/psu/11487 Title: Algorithms for Studying the Impact of Travel Time Reliability Along Multisegment Trucking Freight Corridors Author: Figliozzi, Miguel, Wheeler, Nikki, Albright, Eric, Walker, Lindsay, Sarkar, Shreemoyee, Rice, Danielle Year: 2011 Performance measures allow planners and engineers to monitor and evaluate transportation facilities or projects and to justify the allocation of funds among alternative transportation improvement options. To capture the impact of corridor congestion on freight vehicles, new tools and methodologies are developed to analyze data from commercial vehicles and produce performance measures such as travel time, speed, and travel time reliability. Because long freight corridors comprise segments with varying reliability characteristics, the objective was to develop a programming logic that would use available truck Global Positioning System data to (a) identify natural segments or regions in a corridor between urban centers, Interstate junctions, or rural areas and (b) estimate corridorwide impact of travel time unreliability. The case study presented investigates the I-5 corridor in Oregon. The research applies statistical techniques to compute vehicle travel time and reliability for freight movements within each segment. The proposed methodology has been used successfully to identify distinct segments and characteristics of travel time reliability in freight corridors. Travel time information was used to compute cost effects of delays within rural and urban areas along the I-5 corridor. The research presents an advance in the processing and aggregation of Global Positioning System truck data to produce succinct yet informative performance measures and segments. For more information: http://archives.pdx.edu/ds/psu/11487 Close

• 6. [Article] Safety Effectiveness of Pedestrian Crossing Treatments

  Over the last decade, the transportation agencies in Oregon have systematically enhanced many pedestrian crossings at mid-block locations with Rectangular Rapid Flashing Beacons (RRFBs), Flashing Yellow ...

  Citation × Citation Citation Abstract Copy Title: Safety Effectiveness of Pedestrian Crossing Treatments Author: Monsere, Christopher Year: 2017 Over the last decade, the transportation agencies in Oregon have systematically enhanced many pedestrian crossings at mid-block locations with Rectangular Rapid Flashing Beacons (RRFBs), Flashing Yellow Beacons (Flash), and high visibility crosswalk markings (Hi-Vis). Enhancements often included the installation of refuge medians. This study explored the safety performance of these enhanced crossings, categorized by enhancement type. Data were collected on 191 crossings that included installation year, geometric features, surrounding land use, traffic volumes, and the number of crashes. Because pedestrian volume at the locations was unavailable, a pedestrian activity level variable was developed. Target crashes for analysis were identified as pedestrian and rear-end. The analysis of the before-after crash patterns showed a reduction in the pedestrian crash severity after the installation of the crosswalk enhancements. Risk ratios, calculated by the unadjusted crash frequency relative to the years of operation in each analysis category, were calculated. For pedestrian crashes, risk ratios increased with the number of lanes, posted speed, and estimated pedestrian activity level. Similar trends were observed for rear-end crashes. Due to sample size limitations, safety effectiveness was only estimated for the 19 RRFBs locations. Lack of pedestrian volumes limited the development of a safety performance function (SPF) for the pedestrian crash types. However, a rear-end crash SPF was estimated. Standard methods to estimate a crash modification factor (CMF) were attempted. The recommended CMF for pedestrian crashes is 0.64 +/- 0.26 using a simple before-after analysis and 0.93 +/- 0.22 for rear-end crashes using an empirical Bayes analysis. The final report that the presentation is derived from is available: https://doi.org/10.15760/trec.168 Title: Safety Effectiveness of Pedestrian Crossing Treatments Author: Monsere, Christopher Year: 2017 Over the last decade, the transportation agencies in Oregon have systematically enhanced many pedestrian crossings at mid-block locations with Rectangular Rapid Flashing Beacons (RRFBs), Flashing Yellow Beacons (Flash), and high visibility crosswalk markings (Hi-Vis). Enhancements often included the installation of refuge medians. This study explored the safety performance of these enhanced crossings, categorized by enhancement type. Data were collected on 191 crossings that included installation year, geometric features, surrounding land use, traffic volumes, and the number of crashes. Because pedestrian volume at the locations was unavailable, a pedestrian activity level variable was developed. Target crashes for analysis were identified as pedestrian and rear-end. The analysis of the before-after crash patterns showed a reduction in the pedestrian crash severity after the installation of the crosswalk enhancements. Risk ratios, calculated by the unadjusted crash frequency relative to the years of operation in each analysis category, were calculated. For pedestrian crashes, risk ratios increased with the number of lanes, posted speed, and estimated pedestrian activity level. Similar trends were observed for rear-end crashes. Due to sample size limitations, safety effectiveness was only estimated for the 19 RRFBs locations. Lack of pedestrian volumes limited the development of a safety performance function (SPF) for the pedestrian crash types. However, a rear-end crash SPF was estimated. Standard methods to estimate a crash modification factor (CMF) were attempted. The recommended CMF for pedestrian crashes is 0.64 +/- 0.26 using a simple before-after analysis and 0.93 +/- 0.22 for rear-end crashes using an empirical Bayes analysis. The final report that the presentation is derived from is available: https://doi.org/10.15760/trec.168 Close

• 7. [Article] A Practitioner's Guide to Urban Trip Generation

  In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously ...

  Citation × Citation Citation Abstract Copy Title: A Practitioner's Guide to Urban Trip Generation Author: Currans, Kristina Marie Year: 2017 In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously used across the US and Canada. Only recently, with the third edition of the ITE Trip Generation Handbook, have new data and approaches been adopted. In this study NITC researcher Kristina Currans takes aim at understanding issues inherent in the collection and application of ITE’s data and methods in various urban contexts. This technology transfer guide touches on the main findings from this work. Title: A Practitioner's Guide to Urban Trip Generation Author: Currans, Kristina Marie Year: 2017 In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously used across the US and Canada. Only recently, with the third edition of the ITE Trip Generation Handbook, have new data and approaches been adopted. In this study NITC researcher Kristina Currans takes aim at understanding issues inherent in the collection and application of ITE’s data and methods in various urban contexts. This technology transfer guide touches on the main findings from this work. Close

• 8. [Article] How to Estimate Pedestrian Demand

  There is growing support to improve the quality of the walking environment and make investments to promote pedestrian travel. Such efforts often require analytical non-motorized planning tools to estimate ...

  Citation × Citation Citation Abstract Copy Title: How to Estimate Pedestrian Demand Author: Clifton, Kelly, Singleton, Patrick Allen, Muhs, Christopher D., Schneider, Robert J. Year: 2015 There is growing support to improve the quality of the walking environment and make investments to promote pedestrian travel. Such efforts often require analytical non-motorized planning tools to estimate levels of pedestrian demand that are sensitive to environmental and demographic factors at an appropriate scale. Despite this interest and need, current forecasting tools, particularly regional travel demand models, often fall short. To address this gap, Oregon Metro and NITC researcher Kelly Clifton worked together to develop a pedestrian demand estimation tool. For generations, planners have been using statistical models to forecast travel demand, but these models have traditionally been auto-centered. The new tool will allow planners to allocate infrastructure based on pedestrian demand in the Portland, Oregon metropolitan area. The tool is also designed to be replicable, so that other metropolitan areas can adapt the model to begin estimating pedestrian demand in their cities. Title: How to Estimate Pedestrian Demand Author: Clifton, Kelly, Singleton, Patrick Allen, Muhs, Christopher D., Schneider, Robert J. Year: 2015 There is growing support to improve the quality of the walking environment and make investments to promote pedestrian travel. Such efforts often require analytical non-motorized planning tools to estimate levels of pedestrian demand that are sensitive to environmental and demographic factors at an appropriate scale. Despite this interest and need, current forecasting tools, particularly regional travel demand models, often fall short. To address this gap, Oregon Metro and NITC researcher Kelly Clifton worked together to develop a pedestrian demand estimation tool. For generations, planners have been using statistical models to forecast travel demand, but these models have traditionally been auto-centered. The new tool will allow planners to allocate infrastructure based on pedestrian demand in the Portland, Oregon metropolitan area. The tool is also designed to be replicable, so that other metropolitan areas can adapt the model to begin estimating pedestrian demand in their cities. Close

• 9. [Article] Enhancing Targeted Traffic Enforcement Efforts in Portland, Oregon

  Enforcement is a key component of any comprehensive traffic safety program, and through a unique effort the Portland Office of Transportation (PDOT) partners with schools, the court system, community groups ...

  Citation × Citation Citation Abstract Copy Title: Enhancing Targeted Traffic Enforcement Efforts in Portland, Oregon Author: Coffman, Max, Monsere, Christopher Year: 2006 Enforcement is a key component of any comprehensive traffic safety program, and through a unique effort the Portland Office of Transportation (PDOT) partners with schools, the court system, community groups and the Police Bureau to develop a coordinated citywide program to improve traffic safety. However, like many government agencies, the Police Bureau faces constraints that limit the resources it can devote to traffic safety. In response, PDOT and the Police Bureau’s Traffic Division have instituted a program of Strategic and Focused Enforcement (SAFE) to better allocate limited traffic safety personnel and resources. Using historical crash data, PDOT identified 30 high crash corridors and the Police Bureau directed enforcement to these areas. This paper explores alternative techniques to identify SAFE corridors using more recent crash and driver error data. It also highlights the potential for the city to carry this program through to a more robust, high-profile implementation phase, and the new data analysis options that will become available in the next few years. This study will be useful for other practitioners wishing to engage enforcement as a key ally in improving traffic safety. Title: Enhancing Targeted Traffic Enforcement Efforts in Portland, Oregon Author: Coffman, Max, Monsere, Christopher Year: 2006 Enforcement is a key component of any comprehensive traffic safety program, and through a unique effort the Portland Office of Transportation (PDOT) partners with schools, the court system, community groups and the Police Bureau to develop a coordinated citywide program to improve traffic safety. However, like many government agencies, the Police Bureau faces constraints that limit the resources it can devote to traffic safety. In response, PDOT and the Police Bureau’s Traffic Division have instituted a program of Strategic and Focused Enforcement (SAFE) to better allocate limited traffic safety personnel and resources. Using historical crash data, PDOT identified 30 high crash corridors and the Police Bureau directed enforcement to these areas. This paper explores alternative techniques to identify SAFE corridors using more recent crash and driver error data. It also highlights the potential for the city to carry this program through to a more robust, high-profile implementation phase, and the new data analysis options that will become available in the next few years. This study will be useful for other practitioners wishing to engage enforcement as a key ally in improving traffic safety. Close

• 10. [Article] Leading Pedestrian Intervals Treating the Decision to Implement as a Marginal Benefit-Cost Problem

  To improve the safety of people walking at particular signalized intersections, traffic signal engineers may implement leading pedestrian intervals (LPIs) to provide pedestrians with a walk signal for ...

  Citation × Citation Citation Abstract Copy Title: Leading Pedestrian Intervals Treating the Decision to Implement as a Marginal Benefit-Cost Problem Author: Sharma, Anuj, Smaglik, Edward, Kothuri, Sirisha, Smith, Oliver, Koonce, Peter, Huang, Tingting Year: 2017 To improve the safety of people walking at particular signalized intersections, traffic signal engineers may implement leading pedestrian intervals (LPIs) to provide pedestrians with a walk signal for a few seconds before the parallel vehicular green indication. Previous before-and-after studies and simple economic analyses have indicated that LPIs are low-cost tools that can reduce vehicle–pedestrian conflicts and crashes at some signalized intersections. Despite this evidence, municipalities have little guidance for when to implement LPIs. A marginal benefit–cost framework is developed with quantitative metrics and extends the concept of traffic conflicts and marginal safety–delay trade-offs to analyze the appropriateness of implementing an LPI at specific signalized intersections. The method provides guidance to help quantify the probability of a conflict occurring and direction on whether to implement an LPI at a given location from macroscopic-level inputs, including number of turning movements, crash data, and geometry. A case study with sample data indicated that an LPI was cost-effective for the scenario presented. Title: Leading Pedestrian Intervals Treating the Decision to Implement as a Marginal Benefit-Cost Problem Author: Sharma, Anuj, Smaglik, Edward, Kothuri, Sirisha, Smith, Oliver, Koonce, Peter, Huang, Tingting Year: 2017 To improve the safety of people walking at particular signalized intersections, traffic signal engineers may implement leading pedestrian intervals (LPIs) to provide pedestrians with a walk signal for a few seconds before the parallel vehicular green indication. Previous before-and-after studies and simple economic analyses have indicated that LPIs are low-cost tools that can reduce vehicle–pedestrian conflicts and crashes at some signalized intersections. Despite this evidence, municipalities have little guidance for when to implement LPIs. A marginal benefit–cost framework is developed with quantitative metrics and extends the concept of traffic conflicts and marginal safety–delay trade-offs to analyze the appropriateness of implementing an LPI at specific signalized intersections. The method provides guidance to help quantify the probability of a conflict occurring and direction on whether to implement an LPI at a given location from macroscopic-level inputs, including number of turning movements, crash data, and geometry. A case study with sample data indicated that an LPI was cost-effective for the scenario presented. Close