2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHa... more 2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHakim, NahalZhai, LiangCarrick, GradyFlorida International UniversityFlorida. Department of TransportationFlorida. Department of Transportation. Freight and Multimodal OperationsFlorida. Department of TransportationUnited StatesCountermeasuresCrash analysisCrash causesCrash severityEconomic impactsFreight transportationHigh risk locationsIntersectionsLogitsMotor carriersSpatial analysisTruck crashesTrucking safetyLarge truck crashcritical reasoneconomic appraisalBDV29-977-31Final Report, January 2017 - June 2019This report summarizes the efforts and results of the research project \u201cLarge Truck Crash Analysis for Freight Mobility and Safety Enhancement in Florida\u201d, which was intended to gain more understanding of the patterns and contributing factors of large truck crashes in Florida, to recommend practical countermeasures to reduce crashes involving freight, and to enhance freight mobility and safety. A comprehensive statewide crash analysis was conducted focusing on large truck-involved crashes in the past ten years, between 2007 and 2016. Three different approaches were undertaken to analyze the crash data. A framework was developed to identify the critical reason for individual crashes, which provided insights into the potential causes or factors that lead to increasing risk of a crash. Disaggregate crash severity analysis was conducted to investigate the impacts of contributing factors on crash severity outcomes through random parameter ordered logit (RPOL) models. Spatial analysis was also conducted to illustrate the spatial pattern of large truck crashes and identify concentration or problematics areas, using an ArcGIS Spatial Analyst extension, the Kernel Density tool. Incorporating findings from the three major crash analysis efforts, a data-driven and evidence-based set of countermeasures was developed that target the behavioral factors and critical locations identified from those efforts. A group of selected systemic countermeasures were presented and discussed with some examples representing the common applications. Targeted countermeasures were then recommended for 35 priority locations identified in the state of Florida, including 15 hotspot areas ranked by kernel density and 20 high priority intersections ranked by high crash severity or high crash rate. Last but not least, an economic appraisal approach was recommended that considers the economic impacts of enhanced freight safety and mobility in the project evaluation process. The Large Truck Crash Reduction Benefit Estimator, a spreadsheet-based tool, was developed to facilitate the economic appraisal process.104
2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHa... more 2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHakim, NahalZhai, LiangCarrick, GradyFlorida International UniversityFlorida. Department of TransportationFlorida. Department of Transportation. Freight and Multimodal OperationsFlorida. Department of TransportationUnited StatesCountermeasuresCrash analysisCrash causesCrash severityEconomic impactsFreight transportationHigh risk locationsIntersectionsLogitsMotor carriersSpatial analysisTruck crashesTrucking safetyLarge truck crashcritical reasoneconomic appraisalBDV29-977-31Final Report, January 2017 - June 2019This report summarizes the efforts and results of the research project \u201cLarge Truck Crash Analysis for Freight Mobility and Safety Enhancement in Florida\u201d, which was intended to gain more understanding of the patterns and contributing factors of large truck crashes in Florida, to recommend practical countermeasures to reduce crashes involving freight, and to enhance freight mobility and safety. A comprehensive statewide crash analysis was conducted focusing on large truck-involved crashes in the past ten years, between 2007 and 2016. Three different approaches were undertaken to analyze the crash data. A framework was developed to identify the critical reason for individual crashes, which provided insights into the potential causes or factors that lead to increasing risk of a crash. Disaggregate crash severity analysis was conducted to investigate the impacts of contributing factors on crash severity outcomes through random parameter ordered logit (RPOL) models. Spatial analysis was also conducted to illustrate the spatial pattern of large truck crashes and identify concentration or problematics areas, using an ArcGIS Spatial Analyst extension, the Kernel Density tool. Incorporating findings from the three major crash analysis efforts, a data-driven and evidence-based set of countermeasures was developed that target the behavioral factors and critical locations identified from those efforts. A group of selected systemic countermeasures were presented and discussed with some examples representing the common applications. Targeted countermeasures were then recommended for 35 priority locations identified in the state of Florida, including 15 hotspot areas ranked by kernel density and 20 high priority intersections ranked by high crash severity or high crash rate. Last but not least, an economic appraisal approach was recommended that considers the economic impacts of enhanced freight safety and mobility in the project evaluation process. The Large Truck Crash Reduction Benefit Estimator, a spreadsheet-based tool, was developed to facilitate the economic appraisal process.104
Transportation Research Record: Journal of the Transportation Research Board
Disabled and abandoned vehicles (DAVs) on limited access freeways are exposure risks that can res... more Disabled and abandoned vehicles (DAVs) on limited access freeways are exposure risks that can result in congestion and crashes. Improving law enforcement response to DAVs can reduce their impact and potentially prevent some crashes from occurring. Crowdsourced data, such as Waze user alerts, can provide near real-time information on highway conditions, including the presence of DAVs. The challenge is effectively filtering the data so law enforcement can more efficiently respond to actual DAV incidents. In this paper, over 3.8 million Waze alerts and 329 DAV crashes on Florida limited access roadways from July 1, 2019, to December 31, 2020, were analyzed to determine appropriate matching parameters, characteristics, and potential benefits that could be provided by the Waze alerts. Evaluation of various spatiotemporal buffers to match Waze and crash data showed that buffers of 0.5 km (0.31 mi) and 30 min would provide the best matching. Using these buffers, 41 crashes were found to ha...
Transportation Research Record: Journal of the Transportation Research Board
This research sought to understand secondary crashes involving incident responders in which a cit... more This research sought to understand secondary crashes involving incident responders in which a citation was issued for violation of Florida’s Move Over Law. From 2011 to 2020, there were 519 crashes involving a Move Over Law citation, for which the circumstances of the crashes had required a driver to slow or change lanes because of a stopped responder vehicle. The majority occurred during times other than daylight, and driver distraction and alcohol were notably present in the data. Alcohol increased crash and injury severity and the likelihood of injury. Law enforcement traffic stops were the most common precipitating activity, followed by previous crashes and vehicle disablements. Over two-thirds of crashes involved a law enforcement vehicle, the remainder comprised other responder vehicle types. A distribution of posted speed limits showed that more than half of move over violation crashes occurred on roadways with a posted speed of 45 mph or less. In 41 crashes, a pedestrian was...
United States. Federal Highway Administration. Office of Operations, Feb 1, 2021
Federal Highway Administration2021PDFTech ReportBurgess, Lisa M.Garinger, AmyCarrick, GradyCambri... more Federal Highway Administration2021PDFTech ReportBurgess, Lisa M.Garinger, AmyCarrick, GradyCambridge Systematics, Inc.United States. Federal Highway Administration. Office of OperationsUnited States. Federal Highway Administration. Office of OperationsUnited StatesIncident managementTraffic control centersPerformance measurementLaw enforcementData sharingComputer-aided dispatchTraffic management centerTraffic incident managementTraffic Incident Management performance measuresFHWA-HOP-20-064DTFH61-16-D-00051/693JJ319F000293Final ReportThis Primer describes how integrating data from law enforcement and public safety computer-aided dispatch systems with transportation operating systems can improve incident response, help to save responder lives, and improve safety for travelers on the network. It presents several successful case studies of data sharing partnerships that have resulted in improved operational information as well as improved decision-making data for travelers. The Primer presents several practices that have advanced data sharing relationships between public safety agencies and transportation operating agencies.113
This publication is distributed by the U.S. Department of Transportation, National Highway Traffi... more This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings and conclusions expressed in this publication are those of the authors and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its contents or use thereof. If trade or manufacturers' names are mentioned, it is only because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers.
1 This research has the objective to provide a decision support system for managers who must 2 de... more 1 This research has the objective to provide a decision support system for managers who must 2 decide if a roadway “warrants” the addition of Safety Service Patrol (SSP). Unlike the familiar 3 “signal warrants” that guide the installation of traffic signals at candidate intersections, there are 4 no such guidelines for safety service patrol decisions. A proven framework for deploying 5 intelligent transportation system (ITS) equipment is adapted for this purpose. Meetings with 6 Florida Department of Transportation (FDOT) service patrol program managers, and a survey of 7 national state points of contact for service patrols provided insight into critical factors that might 8 contribute to guidelines. Historical incidents from Florida feed models that predict incidents and 9 crashes on candidate roadways, using proven negative-binomial regression models, like those 10 found in the Highway Safety Manual. Qualitative and quantitative thresholds for critical factors 11 are established i...
i DISCLAIMER The opinions, findings, and conclusions expressed in this publication are those of t... more i DISCLAIMER The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the State of Florida Department of Transportation.
Transportation Research Record: Journal of the Transportation Research Board, 2019
Safety service patrols operate in more than 40 states and territories in the United States and ea... more Safety service patrols operate in more than 40 states and territories in the United States and each program operates with unique vehicles, uniforms, and equipment. Despite the variety of operator uniforms, legal and technical requirements at a national level dictate some choices, though color and style are largely at the discretion of states. Past research confirms that high-visibility safety apparel (HVSA) increases visibility. Biomotion markers on the joints further enhance visibility. The Manual on Uniform Traffic Control Devices specifies that personnel working in the right-of-way wear a Class 2 or 3 HVSA. A survey of states where service patrols operate found the majority use high-visibility yellow-green over red-orange, and Class 3 garments are preferred over Class 2. In relation to the base uniform, there is a mixture of maintenance-type uniforms, polo shirts, and no uniform specification at all. In a survey of Florida service patrol program managers and operators, conveying ...
Transportation Research Record: Journal of the Transportation Research Board, 2018
Safety service patrols are a proven strategy to mitigate the effects of traffic incidents through... more Safety service patrols are a proven strategy to mitigate the effects of traffic incidents through quick clearance, incident management, and assistance to other incident responders like police, fire, emergency medical services, and towing. As encountered by other responders, working on or near roadways presents unique hazards for safety service patrol vehicles and operators. Road Rangers are Florida’s branded safety service patrols and, as a mature program with over 100 beats, a suitable case study for safety. This research combined an analysis of Road Ranger traffic crash data for 3 years with a comprehensive safety survey of more than 200 operators to determine safety characteristics related to service patrols. Comparing 200 Road Ranger traffic crashes from 2014 through 2016 with all Florida freeway crashes for the same time period revealed that Road Ranger crashes are five times more likely to involve a parked vehicle, and involve two or more vehicles 95% of the time. Pedestrian i...
Transportation Research Record: Journal of the Transportation Research Board, 2018
This paper introduces a framework for the design and deployment of safety service patrols (SSP) o... more This paper introduces a framework for the design and deployment of safety service patrols (SSP) on freeways. Three mathematical programming models are proposed, with the targets of minimizing fleet size and total average response time and maximizing social benefits to accommodate various design objectives. Fast heuristic algorithms based on neighborhood searching techniques are presented for solving the optimization problems. In addition, a computer tool with a graphical user interface has been developed that takes roadway segments information as the input and provides real-world recommendations for deployment. The tool was tested using nearly 800 unique Florida roadway segments, totaling over 2,000 centerline freeway miles. The results were consistent with more than 100 current beats of Florida Road Ranger service patrols, and will be used for budget forecasting for the state.
Transportation Research Record: Journal of the Transportation Research Board, 2017
This research had the objective of providing a decision support system for managers who must deci... more This research had the objective of providing a decision support system for managers who must decide whether a roadway warrants the addition of a safety service patrol (SSP). Unlike the familiar signal warrants that guide the installation of traffic signals at candidate intersections, no such guidelines exist for decisions on SSPs. A proven framework for deploying intelligent transportation system equipment is adapted for this purpose. Meetings with managers from the service patrol program of the Florida Department of Transportation and a survey of national state points of contact for service patrols provided insight into critical factors that might contribute to guidelines. Historical incidents from Florida fed models that predict incidents and crashes on candidate roadways by using proven negative binomial regression models like those found in the Highway Safety Manual. Qualitative and quantitative thresholds for critical factors were established in the form of rules in decision ta...
According to the Federal Highway Administration (FHWA), fatalities in highway work zones were up ... more According to the Federal Highway Administration (FHWA), fatalities in highway work zones were up nearly 50% between 1997 and 2003. In 2003 alone, there were 41,000 injuries and 1,028 fatalities in these locations. Increasingly, safety interests are searching for characteristics associated with work zones that contribute to the dangers of such areas. Like many aspects of traffic safety, a better understanding of the contributing factors in crashes can potentially lead to improved countermeasures. Examining crash data is a principal method by which engineers, police, and safety advocates attempt to determine those factors, but such data are often incomplete. The prospect of improving the data set requires examining the potential of a supplemental data collection system. Using qualitative research, work zone stakeholders potentially provide a better understanding of work zone incidents, rendering new data elements. Creating a web-based supplemental collection system can assist police in gathering the data while completing the current x traffic crash report. Supplemental data elements and collection systems have the potential to enrich the data set, and bolster the cause of safety.
2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHa... more 2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHakim, NahalZhai, LiangCarrick, GradyFlorida International UniversityFlorida. Department of TransportationFlorida. Department of Transportation. Freight and Multimodal OperationsFlorida. Department of TransportationUnited StatesCountermeasuresCrash analysisCrash causesCrash severityEconomic impactsFreight transportationHigh risk locationsIntersectionsLogitsMotor carriersSpatial analysisTruck crashesTrucking safetyLarge truck crashcritical reasoneconomic appraisalBDV29-977-31Final Report, January 2017 - June 2019This report summarizes the efforts and results of the research project \u201cLarge Truck Crash Analysis for Freight Mobility and Safety Enhancement in Florida\u201d, which was intended to gain more understanding of the patterns and contributing factors of large truck crashes in Florida, to recommend practical countermeasures to reduce crashes involving freight, and to enhance freight mobility and safety. A comprehensive statewide crash analysis was conducted focusing on large truck-involved crashes in the past ten years, between 2007 and 2016. Three different approaches were undertaken to analyze the crash data. A framework was developed to identify the critical reason for individual crashes, which provided insights into the potential causes or factors that lead to increasing risk of a crash. Disaggregate crash severity analysis was conducted to investigate the impacts of contributing factors on crash severity outcomes through random parameter ordered logit (RPOL) models. Spatial analysis was also conducted to illustrate the spatial pattern of large truck crashes and identify concentration or problematics areas, using an ArcGIS Spatial Analyst extension, the Kernel Density tool. Incorporating findings from the three major crash analysis efforts, a data-driven and evidence-based set of countermeasures was developed that target the behavioral factors and critical locations identified from those efforts. A group of selected systemic countermeasures were presented and discussed with some examples representing the common applications. Targeted countermeasures were then recommended for 35 priority locations identified in the state of Florida, including 15 hotspot areas ranked by kernel density and 20 high priority intersections ranked by high crash severity or high crash rate. Last but not least, an economic appraisal approach was recommended that considers the economic impacts of enhanced freight safety and mobility in the project evaluation process. The Large Truck Crash Reduction Benefit Estimator, a spreadsheet-based tool, was developed to facilitate the economic appraisal process.104
2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHa... more 2019PDFTech ReportJin, XiaAsgari, HamidrezaLee, MingRahimi, AlirezaAzimi, GhazalehBejleri, IlirHakim, NahalZhai, LiangCarrick, GradyFlorida International UniversityFlorida. Department of TransportationFlorida. Department of Transportation. Freight and Multimodal OperationsFlorida. Department of TransportationUnited StatesCountermeasuresCrash analysisCrash causesCrash severityEconomic impactsFreight transportationHigh risk locationsIntersectionsLogitsMotor carriersSpatial analysisTruck crashesTrucking safetyLarge truck crashcritical reasoneconomic appraisalBDV29-977-31Final Report, January 2017 - June 2019This report summarizes the efforts and results of the research project \u201cLarge Truck Crash Analysis for Freight Mobility and Safety Enhancement in Florida\u201d, which was intended to gain more understanding of the patterns and contributing factors of large truck crashes in Florida, to recommend practical countermeasures to reduce crashes involving freight, and to enhance freight mobility and safety. A comprehensive statewide crash analysis was conducted focusing on large truck-involved crashes in the past ten years, between 2007 and 2016. Three different approaches were undertaken to analyze the crash data. A framework was developed to identify the critical reason for individual crashes, which provided insights into the potential causes or factors that lead to increasing risk of a crash. Disaggregate crash severity analysis was conducted to investigate the impacts of contributing factors on crash severity outcomes through random parameter ordered logit (RPOL) models. Spatial analysis was also conducted to illustrate the spatial pattern of large truck crashes and identify concentration or problematics areas, using an ArcGIS Spatial Analyst extension, the Kernel Density tool. Incorporating findings from the three major crash analysis efforts, a data-driven and evidence-based set of countermeasures was developed that target the behavioral factors and critical locations identified from those efforts. A group of selected systemic countermeasures were presented and discussed with some examples representing the common applications. Targeted countermeasures were then recommended for 35 priority locations identified in the state of Florida, including 15 hotspot areas ranked by kernel density and 20 high priority intersections ranked by high crash severity or high crash rate. Last but not least, an economic appraisal approach was recommended that considers the economic impacts of enhanced freight safety and mobility in the project evaluation process. The Large Truck Crash Reduction Benefit Estimator, a spreadsheet-based tool, was developed to facilitate the economic appraisal process.104
Transportation Research Record: Journal of the Transportation Research Board
Disabled and abandoned vehicles (DAVs) on limited access freeways are exposure risks that can res... more Disabled and abandoned vehicles (DAVs) on limited access freeways are exposure risks that can result in congestion and crashes. Improving law enforcement response to DAVs can reduce their impact and potentially prevent some crashes from occurring. Crowdsourced data, such as Waze user alerts, can provide near real-time information on highway conditions, including the presence of DAVs. The challenge is effectively filtering the data so law enforcement can more efficiently respond to actual DAV incidents. In this paper, over 3.8 million Waze alerts and 329 DAV crashes on Florida limited access roadways from July 1, 2019, to December 31, 2020, were analyzed to determine appropriate matching parameters, characteristics, and potential benefits that could be provided by the Waze alerts. Evaluation of various spatiotemporal buffers to match Waze and crash data showed that buffers of 0.5 km (0.31 mi) and 30 min would provide the best matching. Using these buffers, 41 crashes were found to ha...
Transportation Research Record: Journal of the Transportation Research Board
This research sought to understand secondary crashes involving incident responders in which a cit... more This research sought to understand secondary crashes involving incident responders in which a citation was issued for violation of Florida’s Move Over Law. From 2011 to 2020, there were 519 crashes involving a Move Over Law citation, for which the circumstances of the crashes had required a driver to slow or change lanes because of a stopped responder vehicle. The majority occurred during times other than daylight, and driver distraction and alcohol were notably present in the data. Alcohol increased crash and injury severity and the likelihood of injury. Law enforcement traffic stops were the most common precipitating activity, followed by previous crashes and vehicle disablements. Over two-thirds of crashes involved a law enforcement vehicle, the remainder comprised other responder vehicle types. A distribution of posted speed limits showed that more than half of move over violation crashes occurred on roadways with a posted speed of 45 mph or less. In 41 crashes, a pedestrian was...
United States. Federal Highway Administration. Office of Operations, Feb 1, 2021
Federal Highway Administration2021PDFTech ReportBurgess, Lisa M.Garinger, AmyCarrick, GradyCambri... more Federal Highway Administration2021PDFTech ReportBurgess, Lisa M.Garinger, AmyCarrick, GradyCambridge Systematics, Inc.United States. Federal Highway Administration. Office of OperationsUnited States. Federal Highway Administration. Office of OperationsUnited StatesIncident managementTraffic control centersPerformance measurementLaw enforcementData sharingComputer-aided dispatchTraffic management centerTraffic incident managementTraffic Incident Management performance measuresFHWA-HOP-20-064DTFH61-16-D-00051/693JJ319F000293Final ReportThis Primer describes how integrating data from law enforcement and public safety computer-aided dispatch systems with transportation operating systems can improve incident response, help to save responder lives, and improve safety for travelers on the network. It presents several successful case studies of data sharing partnerships that have resulted in improved operational information as well as improved decision-making data for travelers. The Primer presents several practices that have advanced data sharing relationships between public safety agencies and transportation operating agencies.113
This publication is distributed by the U.S. Department of Transportation, National Highway Traffi... more This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings and conclusions expressed in this publication are those of the authors and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its contents or use thereof. If trade or manufacturers' names are mentioned, it is only because they are considered essential to the object of the publication and should not be construed as an endorsement. The United States Government does not endorse products or manufacturers.
1 This research has the objective to provide a decision support system for managers who must 2 de... more 1 This research has the objective to provide a decision support system for managers who must 2 decide if a roadway “warrants” the addition of Safety Service Patrol (SSP). Unlike the familiar 3 “signal warrants” that guide the installation of traffic signals at candidate intersections, there are 4 no such guidelines for safety service patrol decisions. A proven framework for deploying 5 intelligent transportation system (ITS) equipment is adapted for this purpose. Meetings with 6 Florida Department of Transportation (FDOT) service patrol program managers, and a survey of 7 national state points of contact for service patrols provided insight into critical factors that might 8 contribute to guidelines. Historical incidents from Florida feed models that predict incidents and 9 crashes on candidate roadways, using proven negative-binomial regression models, like those 10 found in the Highway Safety Manual. Qualitative and quantitative thresholds for critical factors 11 are established i...
i DISCLAIMER The opinions, findings, and conclusions expressed in this publication are those of t... more i DISCLAIMER The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the State of Florida Department of Transportation.
Transportation Research Record: Journal of the Transportation Research Board, 2019
Safety service patrols operate in more than 40 states and territories in the United States and ea... more Safety service patrols operate in more than 40 states and territories in the United States and each program operates with unique vehicles, uniforms, and equipment. Despite the variety of operator uniforms, legal and technical requirements at a national level dictate some choices, though color and style are largely at the discretion of states. Past research confirms that high-visibility safety apparel (HVSA) increases visibility. Biomotion markers on the joints further enhance visibility. The Manual on Uniform Traffic Control Devices specifies that personnel working in the right-of-way wear a Class 2 or 3 HVSA. A survey of states where service patrols operate found the majority use high-visibility yellow-green over red-orange, and Class 3 garments are preferred over Class 2. In relation to the base uniform, there is a mixture of maintenance-type uniforms, polo shirts, and no uniform specification at all. In a survey of Florida service patrol program managers and operators, conveying ...
Transportation Research Record: Journal of the Transportation Research Board, 2018
Safety service patrols are a proven strategy to mitigate the effects of traffic incidents through... more Safety service patrols are a proven strategy to mitigate the effects of traffic incidents through quick clearance, incident management, and assistance to other incident responders like police, fire, emergency medical services, and towing. As encountered by other responders, working on or near roadways presents unique hazards for safety service patrol vehicles and operators. Road Rangers are Florida’s branded safety service patrols and, as a mature program with over 100 beats, a suitable case study for safety. This research combined an analysis of Road Ranger traffic crash data for 3 years with a comprehensive safety survey of more than 200 operators to determine safety characteristics related to service patrols. Comparing 200 Road Ranger traffic crashes from 2014 through 2016 with all Florida freeway crashes for the same time period revealed that Road Ranger crashes are five times more likely to involve a parked vehicle, and involve two or more vehicles 95% of the time. Pedestrian i...
Transportation Research Record: Journal of the Transportation Research Board, 2018
This paper introduces a framework for the design and deployment of safety service patrols (SSP) o... more This paper introduces a framework for the design and deployment of safety service patrols (SSP) on freeways. Three mathematical programming models are proposed, with the targets of minimizing fleet size and total average response time and maximizing social benefits to accommodate various design objectives. Fast heuristic algorithms based on neighborhood searching techniques are presented for solving the optimization problems. In addition, a computer tool with a graphical user interface has been developed that takes roadway segments information as the input and provides real-world recommendations for deployment. The tool was tested using nearly 800 unique Florida roadway segments, totaling over 2,000 centerline freeway miles. The results were consistent with more than 100 current beats of Florida Road Ranger service patrols, and will be used for budget forecasting for the state.
Transportation Research Record: Journal of the Transportation Research Board, 2017
This research had the objective of providing a decision support system for managers who must deci... more This research had the objective of providing a decision support system for managers who must decide whether a roadway warrants the addition of a safety service patrol (SSP). Unlike the familiar signal warrants that guide the installation of traffic signals at candidate intersections, no such guidelines exist for decisions on SSPs. A proven framework for deploying intelligent transportation system equipment is adapted for this purpose. Meetings with managers from the service patrol program of the Florida Department of Transportation and a survey of national state points of contact for service patrols provided insight into critical factors that might contribute to guidelines. Historical incidents from Florida fed models that predict incidents and crashes on candidate roadways by using proven negative binomial regression models like those found in the Highway Safety Manual. Qualitative and quantitative thresholds for critical factors were established in the form of rules in decision ta...
According to the Federal Highway Administration (FHWA), fatalities in highway work zones were up ... more According to the Federal Highway Administration (FHWA), fatalities in highway work zones were up nearly 50% between 1997 and 2003. In 2003 alone, there were 41,000 injuries and 1,028 fatalities in these locations. Increasingly, safety interests are searching for characteristics associated with work zones that contribute to the dangers of such areas. Like many aspects of traffic safety, a better understanding of the contributing factors in crashes can potentially lead to improved countermeasures. Examining crash data is a principal method by which engineers, police, and safety advocates attempt to determine those factors, but such data are often incomplete. The prospect of improving the data set requires examining the potential of a supplemental data collection system. Using qualitative research, work zone stakeholders potentially provide a better understanding of work zone incidents, rendering new data elements. Creating a web-based supplemental collection system can assist police in gathering the data while completing the current x traffic crash report. Supplemental data elements and collection systems have the potential to enrich the data set, and bolster the cause of safety.
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Papers by Grady Carrick