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2017

Transportation Engineering

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Full-Text Articles in Engineering

16-11 Microsimulation Of The Impact Of Access Management Practices To Pedestrians, Deo Chimba, Kevin Soloka Dec 2017

16-11 Microsimulation Of The Impact Of Access Management Practices To Pedestrians, Deo Chimba, Kevin Soloka

Transportation Research Center Reports

The study applied microsimulation to analyze the impact of access management (AM) to the operational performances of vehicles and pedestrians. A conceptual model was developed in VISSIM and VISWALK to examine the effect of access and signals density on different median types to the travel speed, travel time, delay and stopping. Access density, signal density, and presence of median were simulated in a scenario base analysis. The model scenarios shifted through changing both access density and signal density with no median, raised median and TWLT lane to provide interactions of arterial corridors in Nashville. The effect of access density on …


16-02 Enhancing Non-Motorized Mobility Within Construction Zones, Upul Attanayake, Abul Fazal Mazumder, Wjdan Dhaif Sahi Sahi, Mathew Mueller, Dustin Black Dec 2017

16-02 Enhancing Non-Motorized Mobility Within Construction Zones, Upul Attanayake, Abul Fazal Mazumder, Wjdan Dhaif Sahi Sahi, Mathew Mueller, Dustin Black

Transportation Research Center Reports

Acquisition of lanes and sidewalks for construction activities increases congestion and delays and compromises safety. Further, work zones impair access to local businesses, bus stops, nearby facilities, etc., while hindering mobility of pedestrians, cyclists, and emergency responders. The emphasis on non-motorized mobility varies significantly when temporary traffic control management plans are developed for small cities. Due to lack of specific instructions given to contractors and the potential liability issues, contractors tend to completely close access to non-motorized traffic without providing alternate routes or detours. Instead of using a detour, pedestrians and cyclists tend to pass through the construction zone or …


Characterization And Modeling Of Asphalt Concrete For Dynamic Properties And Performances, A S M A. Rahman Dec 2017

Characterization And Modeling Of Asphalt Concrete For Dynamic Properties And Performances, A S M A. Rahman

Civil Engineering ETDs

The recently developed mechanistic-empirical pavement design guide (MEPDG, also known as Pavement M-E design method) uses the nationally calibrated, binder viscosity-based dynamic modulus predictive model for the design and analysis of asphalt pavements. In this study, this model is assessed for its appropriateness for asphalt-aggregate mixtures typically used in New Mexico. In essence, this study investigates the predictability issue of complex modulus of New Mexico mixes. A total of 54 Superpave mixes with different aggregate gradations, air voids, and binder grades were collected from the mixing plants and from the pavement construction sites. The loose asphalt mixtures were then compacted, …


Application Of Real Field Connected Vehicle Data For Aggressive Driving Identification On Horizontal Curves, Arash Jahangiri, Vincent Berardi, Sahar Ghanipoor Machiani Dec 2017

Application Of Real Field Connected Vehicle Data For Aggressive Driving Identification On Horizontal Curves, Arash Jahangiri, Vincent Berardi, Sahar Ghanipoor Machiani

Psychology Faculty Articles and Research

The emerging technology of connected vehicles generates a vast amount of data that could be used to enhance roadway safety. In this paper, we focused on safety applications of a real field connected vehicle data on a horizontal curve. The database contains connected vehicle data that were collected on public roads in Ann Arbor, Michigan with instrumented vehicles. Horizontal curve negotiations are associated with a great number of accidents, which are mainly attributed to driving errors. Aggressive/risky driving is a contributing factor to the high rate of crashes on horizontal curves. Using basic safety message data in connected vehicle data …


On The Fatigue Of Headed Shear Studs In Steel-Concrete Composite Bridge Girders, Brianna Laurene Ovuoba Dec 2017

On The Fatigue Of Headed Shear Studs In Steel-Concrete Composite Bridge Girders, Brianna Laurene Ovuoba

Graduate Theses and Dissertations

Shear connectors are commonly used in steel bridges to join the concrete deck and steel superstructure, providing a mechanism for shear transfer across the steel-concrete interface. The most common shear connector is the headed shear stud. In the current AASHTO LRFD Bridge Specifications on composite design, shear stud fatigue often governs over static strength, and a large number of shear connectors often result. This dissertation investigates headed shear stud fatigue capacities and demands, and provides insight into conservancies in existing design specifications through examination of existing high-traffic bridge performance.

To investigate stud capacity, a total of six high-cycle fatigue tests …


Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh Dec 2017

Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh

Graduate Theses and Dissertations

This research proposes novel solution techniques to optimize two real-world problems in the area of scheduling and transportation. We first consider a model for optimizing the operations of dredges. In this problem, scheduling and assignment decisions are integrated across a finite planning horizon. Additional constraints and problem elements explicitly considered include, but are not limited, to environmental work window restrictions, budget limitations, dredge operation rates and schedule-dependent dredge availability. Our approach makes use of Constraint Programming (CP) to obtain quality and robust solutions within an amount of time small enough to be useful to practitioners. The expanded feature set of …


Effectiveness Of Chain Link Turtle Fence And Culverts In Reducing Turtle Mortality And Providing Connectivity Along U.S. Hwy 83, Valentine National Wildlife Refuge, Nebraska, Usa, Marcel P. Huijser, Kari E. Gunson, Elizabeth R. Fairbank Dec 2017

Effectiveness Of Chain Link Turtle Fence And Culverts In Reducing Turtle Mortality And Providing Connectivity Along U.S. Hwy 83, Valentine National Wildlife Refuge, Nebraska, Usa, Marcel P. Huijser, Kari E. Gunson, Elizabeth R. Fairbank

Nebraska Department of Transportation: Research Reports

We evaluated the effectiveness of existing turtle fences through collecting and analyzing turtle mortality data along U.S. Hwy 83, in and around Valentine National Wildlife Refuge, Nebraska, USA. We also investigated the level of connectivity for turtles provided through the culverts that were originally designed to pass water through a capture-mark-recapture experiment. While fenced valley sections had 33.1% fewer turtle observations than unfenced valley sections, the difference was not significant. However, we think that the effectiveness of the fence can be improved through fence repairs, other modifications of the fences, vegetation maintenance, and extending the length of the fences. Four …


Fiscal Year 2017 Fhwa-536 Report For The Kentucky Transportation Cabinet, Steven Douglas Kreis, Candice Y. Wallace, Bryan Gibson, Sarah M. Mccormack Dec 2017

Fiscal Year 2017 Fhwa-536 Report For The Kentucky Transportation Cabinet, Steven Douglas Kreis, Candice Y. Wallace, Bryan Gibson, Sarah M. Mccormack

Kentucky Transportation Center Research Report

The Federal Highway Administration (FHWA) requires state transportation agencies to submit a biennial report on local highway finances. The purpose of these reports is to provide FHWA with the data it needs to capture the financing of highway activities at the local level. Based on this information, it can identify trends in revenue, expenditures, investments, and program development, and in turn make decisions about future investments. The report, FHWA-536, asks agencies to report on four areas of local highway finance: 1) disposition of highway-user revenues; 2) revenues used for roads and streets identified by source and funding type; 3) road …


Applicability Of Zipper Merge Versus Early Merge In Kentucky Work Zones, Erin Lammers-Staats, Jerry G. Pigman, Brian K. Howell, Adam J. Kirk Dec 2017

Applicability Of Zipper Merge Versus Early Merge In Kentucky Work Zones, Erin Lammers-Staats, Jerry G. Pigman, Brian K. Howell, Adam J. Kirk

Kentucky Transportation Center Research Report

In an effort to improve work zone safety and streamline traffic flows, a number of state transportation agencies (STAs) have experimented with the zipper merge. The zipper merge differs from a conventional, or early, merge in that vehicles do not merge into the lane that remains open immediately after being notified of a lane closure. Rather, vehicles continue to occupy all lanes until they reach the taper, at which point — and directed by signage — vehicles take turns merging into the open lane, creating a zipper pattern. At the request of the Kentucky Transportation Cabinet (KYTC), Kentucky Transportation Center …


Using Historic Pavement Performance Data To Identify And Select Sites For Asphalt Mixture Design Studies, Allyson Richey Dec 2017

Using Historic Pavement Performance Data To Identify And Select Sites For Asphalt Mixture Design Studies, Allyson Richey

Civil Engineering Undergraduate Honors Theses

Since 1997 Arkansas asphalt mixtures have been designed using a procedure commonly known as ‘Superpave’. In a traditional Superpave mix design, the design considers only traditional volumetric parameters; however, recent advances in mix design technology emphasize mixture’s ability to perform in its environment. There are numerous factors which affect the performance characteristics of an asphalt mix. Certainly, the asphalt binder’s performance is a critical variable in this system. Asphalt binders are sensitive to temperature, so much so that their primary parameter on which they are recommended is a function of both temperature and the geographic latitude in which the pavement …


Evaluation Of Opportunities And Challenges Of Using Inrix Data For Real-Time Performance Monitoring And Historical Trend Assessment, Anuj Sharma, Vesal Ahsani, Sandeep Rawat Dec 2017

Evaluation Of Opportunities And Challenges Of Using Inrix Data For Real-Time Performance Monitoring And Historical Trend Assessment, Anuj Sharma, Vesal Ahsani, Sandeep Rawat

Nebraska Department of Transportation: Research Reports

In recent years there has been a growing desire for the use of probe vehicle technology for congestion detection and general infrastructure performance assessment. Unlike costly traditional data collection by loop detectors, wide-area detection using probe-sourced traffic data is significantly different in terms of measurement technique, pricing, coverage, etc. This affects how the new technology is applied and used to solve current traffic problems such as traffic incident management and roadway performance assessment. This report summarizes the experiences and lessons learned while using probe data for traffic operations and safety management in the state of Nebraska and makes recommendations for …


Evaluating The Effectiveness Of A Hybrid Geosynthetic Reinforcement System To Mitigate Differential Heave On Flexible Pavement Due To Expansive Subgrades, Mir Md. Tamim Dec 2017

Evaluating The Effectiveness Of A Hybrid Geosynthetic Reinforcement System To Mitigate Differential Heave On Flexible Pavement Due To Expansive Subgrades, Mir Md. Tamim

Boise State University Theses and Dissertations

Transportation industries encounter substantial challenges with respect to ride quality and serviceability when they deal with expansive soils underneath roadway structures. These soils exhibit swell-shrink behavior with moisture variations, which cause surficial heaving on the pavement structure and cost billions of dollars for the maintenance of pavements. For the past four decades, a particular stretch of US-95 (Oregon line to Elephant Butte) exhibited recurrent swelling distresses due to the underlying expansive soils. Despite remedial measures that exhibited satisfactory results for most of the sections, recurrent damage still continued in few sections. Further research indicated that the problematic soils were located …


16-08 Does Location Matter? Performance Analysis Of The Affordable Housing Programs In Dallas-Fort Worth, Shima Hamidi, Somayeh Moazzeni, Jinat Jahan, Reza Sardari, David Weinreich Nov 2017

16-08 Does Location Matter? Performance Analysis Of The Affordable Housing Programs In Dallas-Fort Worth, Shima Hamidi, Somayeh Moazzeni, Jinat Jahan, Reza Sardari, David Weinreich

Transportation Research Center Reports

On June 2015, the Texas Department of Housing and Community Affairs lost a case in the U.S. Supreme Court due to their failure to provide equitable affordable housing under the Low Income Housing Tax Credit (LIHTC) program. The U.S. Supreme Court decision has shaken the affordable housing definition by highlighting the importance of location in housing affordability. To best assist low-income families, what should ‘high-opportunity areas’ concretely provide? First and foremost is transportation affordability.

Transportation is more than a sheer convenience for Americans. Looking solely at housing costs is a misleading measure of affordability and a disservice to low-income families. …


Field Investigation And Performance Evaluation Of Interface Bonding Between Pavement Layers, Ramendra N. Das Nov 2017

Field Investigation And Performance Evaluation Of Interface Bonding Between Pavement Layers, Ramendra N. Das

LSU Master's Theses

Proper bonding between pavement layers is essential to provide a monolithic pavement structure that allows distribution of loading over a larger area. Inadequate interface bonding may cause debonding or shear failure at the interface due to the accumulation of concentrated tensile stresses at the bottom of the overlay. Tack coat, a light application of asphaltic cement emulsion is applied on the existing surface to create a strong adhesive bond between pavement layers. The objectives of this study are to investigate the effects of various factors affecting bond strength between hot-mix asphalt (HMA) overlay and underlying pavement layers in the field. …


Sustained Flow Index: A Stochastic Measure Of Freeway Performance, Siavash Shojaat Nov 2017

Sustained Flow Index: A Stochastic Measure Of Freeway Performance, Siavash Shojaat

LSU Doctoral Dissertations

The capacity of a road addresses its quantitative traffic carrying ability. The estimation of capacity as a parameter to assess traffic flow performance on freeway facilities has received considerable attention in the literature. Research into the traffic operation at high volumes reveals that the capacity of freeways is not a fixed number, but rather a random variable. Thus, in a stochastic approach to freeway capacity of estimation, the capacity is treated as a random variable generated from a population of flow observations, stemmed from a certain distribution function. Since the type of capacity distribution function is generally not known with …


An Enhanced Bridge Weigh-In-Motion Methodology And A Bayesian Framework For Predicting Extreme Traffic Load Effects Of Bridges, Yang Yu Nov 2017

An Enhanced Bridge Weigh-In-Motion Methodology And A Bayesian Framework For Predicting Extreme Traffic Load Effects Of Bridges, Yang Yu

LSU Doctoral Dissertations

In the past few decades, the rapid growth of traffic volume and weight, and the aging of transportation infrastructures have raised serious concerns over transportation safety. Under these circumstances, vehicle overweight enforcement and bridge condition assessment through structural health monitoring (SHM) have become critical to the protection of the safety of the public and transportation infrastructures. The main objectives of this dissertation are to: (1) develop an enhanced bridge weigh-in-motion (BWIM) methodology that can be integrated into the SHM system for overweight enforcement and monitoring traffic loading; (2) present a Bayesian framework to predict the extreme traffic load effects (LEs) …


Development Of A Mode And Destination Type Joint Choice Model For Hurricane Evacuation, Ruijie Bian Nov 2017

Development Of A Mode And Destination Type Joint Choice Model For Hurricane Evacuation, Ruijie Bian

LSU Doctoral Dissertations

Since Hurricane Katrina, transit evacuation service has been seen to serve critical needs in affected cities and an increasing number of hurricanes have struck the east coast where more people rely on public transportation to evacuate. Thus, it is important to model mode choice in evacuation for a better estimation of evacuation transit demand. In this study, a joint mode and destination type choice model was estimated based on multiple post-storm behavioral surveys from the northeastern seaboard to the Gulf coast. A Nested Logit model specification was used to estimate this joint choice model. The estimated model showed significant linkage …


Development Of System-Based Methodology To Support Ramp Metering Deployment Decisions, Homa Fartash Nov 2017

Development Of System-Based Methodology To Support Ramp Metering Deployment Decisions, Homa Fartash

FIU Electronic Theses and Dissertations

Ramp metering is an effective management strategy, which helps to keep traffic density below the critical value, preventing breakdowns and thus maintaining the full capacity of the freeway. Warrants for ramp metering installation have been developed by a number of states around the nation. These warrants are generally simple and are based on the traffic, geometry, and safety conditions in the immediate vicinity of each ramp (local conditions). However, advanced applications of ramp metering utilize system-based metering algorithms that involve metering a number of on-ramps to address system bottleneck locations. These algorithms have been proven to perform better compared to …


Countywide Bluetooth System: Use Cases & Performance Measures, Shaun Quayle Nov 2017

Countywide Bluetooth System: Use Cases & Performance Measures, Shaun Quayle

PSU Transportation Seminars

Washington County has 124 permanent roadside Bluetooth readers, which passively and in an anonymous fashion collect travel time, speed, and origin-destination information across the major arterials in the urban County. This presentation gives an overview of the program purpose, history, some interesting use cases, and the formation of comparative performance metrics to gauge the magnitude and duration of congestion across the County. These metrics and information will help planners improve travel demand models, consultants improve traffic analyses, operations staff prioritize timing, detection, and maintenance functions, agencies inform traveler information data, and leaders better communicate the story of traffic demand, delay, …


Modeling Performance, Cost, Delivery, And Trip Distribution Of Demand Responsive Transit Systems With Zoning, Mahour Rahimi Nov 2017

Modeling Performance, Cost, Delivery, And Trip Distribution Of Demand Responsive Transit Systems With Zoning, Mahour Rahimi

Doctoral Dissertations

Demand responsive transit (DRT) services are expensive to operate, so it is crucial to understand the factors that drive the agency costs and be able to investigate and predict the effect of possible changes in specific operating parameters as well as demand and service coverage areas on total costs. In this research, we adopt the concept of the analytical model proposed by Daganzo (1978) to present continuum approximation (CA) models that can estimate important service related factors. As the first step, we propose three analytical models to approximate the operation related variables of DRT services; Fleet Size, Vehicle Hours Traveled …


Evaluation Of Roadway Reallocation Projects: Analysis Of Before-And-After Travel Speeds And Congestion Utilizing High-Resolution Bus Transit Data, Miguel A. Figliozzi, Travis B. Glick Nov 2017

Evaluation Of Roadway Reallocation Projects: Analysis Of Before-And-After Travel Speeds And Congestion Utilizing High-Resolution Bus Transit Data, Miguel A. Figliozzi, Travis B. Glick

TREC Final Reports

The traditional process of identifying corridors for road diet improvements involves selecting potential corridors (mostly based on identifying fourlane roads) and conducting a traffic impact analysis of proposed changes on a selected roadway before implementing changes. The evaluation of roadway reallocation projects should include the analysis of traffic volumes, level of service, speeds, queue lengths and bus operations. There are tools and equipment to evaluate effectively traffic volumes and level of service changes in before-and-after studies. However, the detailed evaluation of speed and queue length distributions along a segment are significantly more cumbersome. In addition, the exhaustive evaluation of bus …


Evaluation Of Roadway Reallocation Projects, Miguel Figliozzi Nov 2017

Evaluation Of Roadway Reallocation Projects, Miguel Figliozzi

TREC Project Briefs

This NITC study offers a new methodology for evaluating the before-and-after effects of roadway space reallocation projects.


In-Place Recycling And Reclamation Of Asphaltic Concrete Pavements In Kentucky, David Q. Hunsucker, David L. Allen, R. Clark Graves Nov 2017

In-Place Recycling And Reclamation Of Asphaltic Concrete Pavements In Kentucky, David Q. Hunsucker, David L. Allen, R. Clark Graves

Kentucky Transportation Center Research Report

Full-depth reclamation has been defined by the Asphalt Recycling and Reclaiming Association as a “rehabilitation technique in which the full thickness of the asphalt pavement and a predetermined portion of the underlying material (base, subbase, and/or subgrade) is uniformly pulverized, blended and compacted to provide an upgraded, homogeneous material resulting in a stabilized base course.” The Kentucky Transportation Cabinet has utilized the full-depth reclamation (FDR) process as a method to address asphalt pavements exhibiting widespread base failures. The FDR process transforms the existing hot mix asphalt (HMA) pavement and underlying granular materials into a stabilized base layer. The stabilized layer …


Coaxing His Data From Mandli Pavement Scans, Eric R. Green, William Nicholas Staats, Erin Lammers-Staats, Teng Alex Wang Nov 2017

Coaxing His Data From Mandli Pavement Scans, Eric R. Green, William Nicholas Staats, Erin Lammers-Staats, Teng Alex Wang

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) Division of Planning’s Highway Information Systems (HIS) database provides geometric information about horizontal and vertical curves, but its accuracy is unknown. An updated method of pavement analysis collects data by scanning the pavement as a van equipped with Mandli software drives the area of interest. The scans provide detailed information that can be used to calculate roadway geometry characteristics (e.g., curve radius, cross slope/superelevation, and grade). This study evaluated the ability of the Mandli data to support curve advisory calculations and find a way to utilize Mandli data to improve the existing HIS database. To …


Accelerated Innovation Deployment (Aid) Demonstration: Kytc — Roundabout Installation Project In London, Kentucky, Jeff Jasper, Adam J. Kirk Nov 2017

Accelerated Innovation Deployment (Aid) Demonstration: Kytc — Roundabout Installation Project In London, Kentucky, Jeff Jasper, Adam J. Kirk

Kentucky Transportation Center Research Report

This document serves as the final report on the construction and opening of the Roundabout Project in London, Kentucky (Kentucky Item Number 11‐904.1). This project (hereafter referred to as the London Roundabout) was constructed on the authority of the Kentucky Transportation Cabinet (KYTC), which received an Accelerated Innovation Deployment (AID) Demonstration grant of $1 million to offset project construction costs. The AID Demonstration program requires that award recipients submit a final report to the Federal Highway Administration (FHWA) within six months of project completion. The purpose of this report is to document the project delivery and construction processes, benefits, and …


Webinar: Transportation Benefits Of Parking Cash-Out, Pre-Tax Commuter Benefits, And Parking Surtaxes, Allen Greenberg, James Choe, Sonika Sethi, Colleen Stoll Oct 2017

Webinar: Transportation Benefits Of Parking Cash-Out, Pre-Tax Commuter Benefits, And Parking Surtaxes, Allen Greenberg, James Choe, Sonika Sethi, Colleen Stoll

TREC Webinar Series

The vast majority of employers provide their employees free parking at work, which encourages employees to drive alone. Multiple strategies exist to level the playing field between travel modes and allow employees to select the travel option most beneficial to them without suffering a financial penalty. The U.S. Department of Transportation, Federal Highway Administration sponsored a study to understand the effect parking cash out, pre-tax commuter benefits, and parking surtaxes can have on congestion, emissions, and other driving-related externalities. The study is part of the Administration’s ongoing efforts to increase awareness of solutions to address the transportation issues affecting communities …


Methods For Utilizing Connected Vehicle Data In Support Of Traffic Bottleneck Management, Samaneh Khazraeian Oct 2017

Methods For Utilizing Connected Vehicle Data In Support Of Traffic Bottleneck Management, Samaneh Khazraeian

FIU Electronic Theses and Dissertations

The decision to select the best Intelligent Transportation System (ITS) technologies from available options has always been a challenging task. The availability of connected vehicle/automated vehicle (CV/AV) technologies in the near future is expected to add to the complexity of the ITS investment decision-making process. The goal of this research is to develop a multi-criteria decision-making analysis (MCDA) framework to support traffic agencies’ decision-making process with consideration of CV/AV technologies. The decision to select between technology alternatives is based on identified performance measures and criteria, and constraints associated with each technology.

Methods inspired by the literature were developed for incident/bottleneck …


Application Of Surface Treatments To Improve Fuel Efficiency Of Internal Combustion Engines, Amirabbas Akbarzadeh Oct 2017

Application Of Surface Treatments To Improve Fuel Efficiency Of Internal Combustion Engines, Amirabbas Akbarzadeh

LSU Master's Theses

To improve the tribological performance of contacting surfaces, different surface modification methods can be employed. Surface texturing and surface coating are examples of viable techniques developed for this purpose. Surface texturing involves creating micropatterns on the contacting surfaces while surface coating requires depositing a thin layer of a suitable material on the surface(s) to improve the component’s friction and wear characteristics. The performance of textured surfaces is affected by the geometric characteristic of textures.When dealing with surface coating parameters, the parameters of interests are the type of coating materials and their thicknesses.

The current study aims to experimentally study the …


Advisory Bike Lanes In North America, Michael Williams Oct 2017

Advisory Bike Lanes In North America, Michael Williams

PSU Transportation Seminars

Despite being used successfully for decades in Europe, Advisory Bike Lanes are an emerging facility type in North America and can be an effective tool for communities wishing to provide bicycle lanes on streets that are otherwise too narrow to accommodate them. This talk will introduce the concept and operation of advisory bike lanes and look at some lessons learned from the early installations of this facility in the U.S. and Canada.


Safety Effectiveness Of Pedestrian Crossing Treatments, Christopher Monsere Oct 2017

Safety Effectiveness Of Pedestrian Crossing Treatments, Christopher Monsere

PSU Transportation Seminars

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 …