Showing papers in "Journal of Transportation Engineering-asce in 2015"

Effects of Pavement Surface Conditions on Traffic Crash Severity

Abstract: Improving road safety through proper pavement maintenance is one of the goals of pavement management. Many studies have found that pavement conditions significantly influence traffic safety. Although several studies have explored the relationship between pavement conditions and crash occurrence, the effect of poor pavement conditions on crash severity levels has not been investigated, especially by using a discrete model that can handle ordered data. This paper focuses on the development of the relationship between poor pavement conditions and crash severity levels using a series of Bayesian ordered logistic models for low/medium/high speed roads and single/multiple collision cases. The Bayesian ordered logistic regression models indicated that the poor pavement condition decreases the severity of single-vehicle collisions on low-speed roads whereas it increases their severity on high-speed roads. On the other hand, the poor pavement condition increases the severity of multiple-vehicle crashes on ...

Public Transport Travel-Time Variability Definitions and Monitoring

Abstract: Public Transport Travel Time Variability (PTTV) is essential for understanding the deteriorations in the reliability of travel time, optimizing transit schedules and route choices. This paper establishes the key definitions of PTTV in which firstly include all buses, and secondly include only a single service from a bus route. The paper then analyzes the day-to-day distribution of public transport travel time by using Transit Signal Priority data. A comprehensive approach, using both parametric bootstrapping Kolmogorov-Smirnov test and Bayesian Information Creation technique is developed, recommends Lognormal distribution as the best descriptor of bus travel time on urban corridors. The probability density function of Lognormal distribution is finally used for calculating probability indicators of PTTV. The findings of this study are useful for both traffic managers and statisticians for planning and analyzing the transit systems.

Rolling Resistance Measurement and Model Development

Abstract: There is an increased focus worldwide on understanding and modeling rolling resistance because reducing the rolling resistance by just a few percent will lead to substantial energy savings. This paper reviews the state of the art of rolling resistance research, focusing on measuring techniques, surface and texture modeling, contact models, tire models, and macro-modeling of rolling resistance.

Exploratory Analysis of Lane Changing on Freeways Based on Driver Behavior

Abstract: Lane changing has received much attention as it is a significant component of microscopic traffic simulation. Many studies have focused on the details of the lane changing maneuver from external observation-based data which do not consider the type of driver performing the maneuver. The research reported in this paper relates the physical details of freeway lane changing to the type of driver performing the maneuver. Forty-six research participants drove an instrumented vehicle and performed a combined total of 726 freeway lane changes. Each research participant was categorized into one of four groups ranging from conservative to aggressive based on cluster analysis. The data were analyzed to identify any trends between the different driver types and their lane changing characteristics, specifically lane changing duration and gap acceptance characteristics. In general, more conservative drivers have greater lane changing durations than aggressive drivers. The gap acceptance comparison among driver...

Identification and Prioritization of Critical Transportation Infrastructure: Case Study of Coastal Flooding

Abstract: In order to better inform transportation decision makers of the criticality of transportation infrastructure, this paper explores an accessibility-based criticality prioritization methodology to identify and prioritize critical transportation infrastructure. In particular, the methodology evaluates the network-wide impacts of infrastructure degradation based on the increase in travel cost taking origin importance, destination attractiveness, and traffic congestion into account. The methodology is applied to the road network of Hillsborough County, Florida, threatened by flood risk from storm surge, sea-level rise, and intense precipitation. Light detection and ranging digital elevation data, transportation infrastructure and network data, and zone-based population data of the county are processed for analysis. The approach yields results of not only the criticality of transportation infrastructure under flooding impact but also the most vulnerable zones as a result of infrastructure inundation. Th...

Critical Assessment of an Enhanced Traffic Sign Detection Method Using Mobile LiDAR and INS Technologies

Abstract: Traffic signs are important roadway assets that provide critical guidance, including regulations and safety-related information, to road users. Traffic signs need to be inventoried by transportation agencies. However, the traditional manual methods carried out in the field are dangerous, labor-intensive, and time-consuming. There is a need to develop alternative methods to cost-effectively inventory traffic signs. The research reported in this paper, sponsored by the U.S. DOT Research and Innovative Technology Administration Program, is to critically assess an alternative traffic sign inventory method using mobile light detection and ranging (LiDAR), and inertial navigation system (INS), technologies. The contribution of this paper is three-fold, as follows: (1) an alternative traffic sign inventory method is proposed using mobile LiDAR and INS technologies, (2) a key LiDAR parameter calibration procedure (including a sensitivity study of the key parameters) is proposed to achieve a desirable traf...

Framework for Development and Comprehensive Comparison of Empirical Pavement Performance Models

Abstract: Empirical performance-prediction models are a central part of every network-level pavement management system. In this regard, a variety of novel techniques including computational intelligence have been applied, mainly without a systematic approach to ensure compliance with principles of pavement engineering. In this study, a framework is provided for development and comprehensive comparison of alternative techniques for pavement performance modeling. As an example, several machine-learning techniques are compared in developing flexible pavement-roughness prediction models using Federal Highway Administration (FHWA’s) long-term pavement performance (LTPP) data. Three important principles of model development—maximum likelihood, consistency, and parsimony—are considered in providing a robust parameterization guideline. Variant architectures of artificial neural networks (ANN), radial basis function (RBF) networks, and support vector machines (SVM) are tested to determine the optimum parameters. Fin...

Automatic Horizontal Curve Identification and Measurement Method Using GPS Data

Abstract: Horizontal curves play a critical role in roadway safety by providing a smooth transition between tangent sections. Because radii of horizontal curves are one of the most fundamental elements in roadway geometry design, transportation agencies, e.g., state DOTs, need to measure them to support network-level safety analysis. However, the traditional methods that are commonly used by transportation agencies, e.g., plan sheet reading method and chord-offset method, are time consuming, labor intensive, and inaccurate. Although some semiautomatic and automatic methods have been developed using global positioning system (GPS) data and/or geographic information system (GIS) functions in recent years, these methods are not yet ready to be practically used in a network-level analysis because they either require intensive manual intervention or lack of the capability in automatically identifying complex curves. This study is aimed to develop a new method using widely available GPS data that can automaticall...

Evaluation of Performance Measures for Two-Lane Intercity Highways under Mixed Traffic Conditions

Abstract: Traffic performance of a highway is expressed in terms of level of service (LOS). It is a major input to important decisions on public fund investments. Because of its unique operational characteristics, evaluation of traffic performance on two-lane highways is a critical task. This research examines the applicability of various performance measures for two-lane highways under mixed traffic conditions and assigns threshold values for different levels of service based on the best performance measure observed. Graphical and statistical analyses are carried out among the six most popular performance measures and traffic volume, but none of the considered measures are found to be reliable. A new parameter, number of followers (NF), which is defined as the number of vehicles traveling with a gap less than 2.6 s, is found to have good correlation with traffic volume but it does not reflect the true congestion conditions of a roadway. Therefore, the NF is further modified to the number of followers as a ...

Developing a 24-Hour Large-Scale Microscopic Traffic Simulation Model for the Before-and-After Study of a New Tolled Freeway in the Washington, DC–Baltimore Region

Abstract: For determining highly disaggregate details about traffic dynamics, microscopic traffic simulation has long proven to be a valuable tool for the evaluation of development plans and operation/control strategies. With recent advances in computing capabilities, research interest in large-scale microscopic simulation has never been greater. This case study develops a 24-h large-scale microscopic traffic simulation model for the Washington, DC, metropolitan area. The model consists of over 7,000 links, 3,500 nodes, 400 signalized intersections, and over 40,000 origin-destination pairs. Various field measurements, such as time-dependent traffic counts and corridor travel times, have been used for model calibration/validation. The EPA’s Motor Vehicle Emission Simulator is linked with the microscopic simulation model for the estimation of environmental impacts. The calibrated model system has been used to comprehensively evaluate a newly built toll road in Maryland, the Intercounty Connector. Various netw...

Developing Passenger-Car Equivalents for Heavy Vehicles in Entry Flow at Roundabouts

Abstract: This study develops passenger-car equivalents (PCEs) for heavy vehicles at roundabouts. For this task, the movements of cars and heavy vehicles were observed using video records collected from three roundabouts in Vermont; Ontario, Canada; and Wisconsin. The PCE was developed such that the variation in the entry capacity in a various mix of cars and heavy vehicles was minimized. The PCE was also applied to the prediction of the entry capacity using a roundabout capacity model. For the model inputs, the study adjusted the critical headway and the follow-up headway to account for the difference in driver’s gap acceptance behavior between cars and heavy vehicles. The result shows that the PCEs for heavy trucks and light trucks are 1.5–2.5 and 1.0–1.5, respectively, at the three roundabouts. In particular, the PCE for light trucks was lower than a default value of 2.0. The result also shows that the established model generally predicted the capacity more accurately when the critical headway and the fo...

Finite-Element Analysis of Stress Concentration around Dowel Bars in Jointed Plain Concrete Pavement

Abstract: Stresses in the concrete surrounding dowel bars is a major factor that contributes to transverse joint distress in jointed plain concrete pavement (JPCP). In this study, a distribution of stresses around dowel bars was analyzed with special attention to compressive and tensile stresses, which are responsible for cracks’ initiation and propagation. Calculations considering diameter, spacing, and length of dowels in JPCP were made using the finite-element method (FEM). Sliding interfaces with friction that permit separation between dowels and surface concrete were modeled using the full cylindrical surface between each dowel and the surrounding concrete. Practical functional relationships among the studied parameters may be useful in the calculation of maximal stresses in concrete around a dowel bar in dependence on its characteristics. Knowledge about the mechanical behavior of dowel bars at their contact with concrete is important to develop effective doweled joints and to improve the load transfe...

Rail–Truck Multimodal Freight Collaboration: Truck Freight Carrier Perspectives in the United States

Abstract: Due to the impacts of highway congestion, truck driver shortage, the need for energy security, and the increasing revenue gaps to finance highway infrastructure construction and renewal, there is a critical need to explore the opportunities and barriers to rail-truck multimodal transportation paradigms. This study proposes a two-step modeling approach to explore truck freight carrier perspectives on the factors that foster/impede their willingness to collaborate with rail freight carriers through multimodal freight collaboration, and how these factors are correlated with their operational and behavioral characteristics. Understanding these correlations can provide rail freight carrier decision makers insights for the design of targeted mechanisms that will be required for such collaborations to come to fruition, including: (1) adjusting the rail carrier operations; (2) adopting technology that is synergistic with those of truck freight carriers; (3) designs for uncontainerized cargo; and (4) impro...

Analysis of Crash Risks by Collision Type at Freeway Diverge Area Using Multivariate Modeling Technique

Abstract: Crashes present different collision types at freeway diverge areas. The research reported in this paper applies the multivariate modeling technique to evaluate the crash risks by collision type. Three years crash data are obtained from 282 freeway exit ramps. Three types of crashes are considered [i.e., (1) rear-end, (2) sideswipe, and (3) angle collisions]. A multivariate Poisson-lognormal (MVPLN) model is estimated to jointly evaluate the impacts of explanatory variables on different collision risks. For comparison purpose, univariate negative binomial (NB) models are also estimated based on the same dataset. The results show that the MVPLN model successfully captures the correlation of latent effects among the crash counts of different collision types. Thus, the MNPLN model estimates the impacts of variables more accurately than the NB model. The MVPLN model is found outperform the NB models in predicting the crash count of each collision type. Findings of this paper can help better understand ...

Calibration and Application of Treatment Performance Models in a Pavement Management System in Tennessee

Abstract: The usage of locally calibrated performance models and other related parameters is necessary in order to utilize the pavement management system (PMS) for maintenance strategy decision-making. In this study, the performance models of typical asphalt resurfacing treatments used in Tennessee were calibrated for the PMS by investigating historical maintenance projects. The multiple regression method was employed to analyze the influence of pretreatment PSI, traffic level, overlay thickness, and milling depth on the post-treatment performance curves. Specific designs of asphalt overlays and performance classes were determined according to the regression analysis. The performance curves for each identified treatment method at different performance classes were established and calibrated for the PMS. Rehabilitation trigger values, typical treatments and decision trees for pavement with different functional classes were determined and designed by investigating the historical maintenance projects. Utilizing the calibrated models, pavement maintenance optimization analyses were performed on a network level. The study has found that pavement with lower pretreatment roughness, thick overlay, and deep milling deteriorated at slower rate. Pavement with high traffic levels tended to have lower post-treatment roughness. The distress condition decreases much faster than smoothness. The most cost-effective network level maintenance strategy can be determined by conducting a network optimization analysis with a sufficient high budget limit. It is recommended that an optimized maintenance budget allocation should include combining cost-effectiveness, rolling unused budget over fiscal years, and re-distributing budget among different maintenance regions.

Optimal Modification of Urban Bus Network Routes Using a Genetic Algorithm

Abstract: The bus network design problem refers to a determination of optimizing the network of bus routes, usually in urban areas. The optimal routes must comply with a given passenger demand matrix and attain a compromise best solution from the user, the operator, and the community. This paper proposes the use of a genetic algorithm as a tool to handle the complexity of the bus network design problem. The methodology developed considers a mechanism to maintain as many satisfactory routes of the existing network as possible and, at the same time, to incorporate experience-based suggestions, such as minimizing of the number of transfers required by a passenger, into the revised bus network. The solution method, using genetic algorithm, has four steps: (1) generating a set of potential routes, (2) designing the bus network, (3) checking the routes for implementation, and (4) examining the extension of routes for improvement. The proposed method is validated through a benchmark bus network and a case study. T...

Time-Headway Distributions on an Expressway: Case of Bangkok

Abstract: Traffic flow modeling is one of the fundamental keys to solving a traffic engineering problem. Among many parameters, time headway is frequently used to model traffic flow characteristics. A statistical analysis of time headways is immensely important to both theoretical traffic modeling and simulation-based traffic modeling. Basically, it allows researchers to describe an inherently random pattern of traffic flows. Past studies have mainly focused on the time headways of vehicles on highways, freeways, and arterials. However, studies of time headways on urban expressways are rather limited and still need further investigation. In this paper, the author investigates and characterizes the time-headway distributions of vehicles traveling on an urban expressway in Bangkok, Thailand. Particularly, the exponential distribution, the lognormal distribution, and the generalized extreme value (GEV) distribution are used to model the time headways. It is found that the GEV distribution is most effective in modeling time headways. In fact, the GEV distribution can describe more than 90% of the empirical distributions on most lanes and sections of the expressway. On the other hand, the exponential distribution is the least effective distribution. It can only describe the empirical distributions during the periods when the traffic is extremely light.

Statistical Analyses of Field Serviceability of Throw-and-Roll Pothole Patches

Abstract: In order to evaluate the effectiveness of different pothole patching methods and materials, it is necessary to conduct a long-term field survey of patches installed at different environmental and traffic conditions. The research reported in this paper investigated the service life of different throw-and-roll pothole patches through a 14-month field survey. Three statistical methods, including (1) logistic regression, (2) classification tree, and (3) survival analysis, were employed to characterize the influence of different factors on the service life of installed patches, and to identify the performance of different patching materials. The factors investigated in the research reported in this paper included the length, width, and depth of patches; traffic level; speed limit; and freeze times. All the three statistical methods identified similar trends of the significance of factors and performance rankings of materials. Generally, patches installed on road sections with less freeze cycles, lower ...

Soil Resilient Modulus Regressed from Physical Properties and Influence of Seasonal Variation on Asphalt Pavement Performance

Abstract: Subgrade soil, as the critical underlying support for other pavement layers and traffic loads, should be stiff enough to maintain the integrity of pavement structures and the smoothness of pavement surface. The resilient modulus, as an indicator of subgrade stiffness, is an essential input in the American Association of State Highway and Transportation Officials (AASHTO) Mechanistic-Empirical Pavement Design Guide (MEPDG). At input level 1 of MEPDG, the MEPDG generalized model is required to describe resilient modulus of subgrade soil, and the coefficients of this model are used for pavement design. The change of the resilient modulus model has raised the interest of many state highway agencies and made it necessary to convert old resilient modulus test data into new ones required for the MEPDG model. In this study, the coefficients of the generalized and the universal models for soil resilient modulus were obtained through regression of the results of 13 soils in Tennessee. The coefficients of the two models were also compared. There is a potential risk that the coefficients from the universal model may be mistakenly used in the MEPDG instead of those coefficients from the generalized model. The consequence of this improper use was demonstrated in the comparison between the miscalculated and the real resilient moduli. The coefficients of the generalized model were correlated to soil physical properties, which provided an alternate time-saving and economical method to obtain soil resilient modulus as level 2 inputs. The coefficients were obtained at different post-compaction water contents, to allow the estimation of pavement response under seasonal moisture variation of subgrade. Rutting and roughness of two typical pavement sections were analyzed to investigate the influence of the seasonal variation of soil resilient modulus on pavement performance. The results showed that moisture variation had a significant effect on subgrade resilient modulus and, subsequently, on pavement performance. It is recommended that seasonal change in soil resilient modulus be considered in the analysis on pavement performance.

Life-Cycle Assessment of Diesel-Electric Hybrid and Conventional Diesel Trucks for Deliveries

Abstract: Purolator is a Canadian courier company that recently introduced hybrid electric vehicles (HEVs) into their fleets. This paper estimates the fuel savings and greenhouse gas (GHG) reductions for Purolator’s hybrid trucks using a life-cycle assessment executed with GHGenius, a Government of Canada model. Overall, it was found that Purolator’s hybrid diesel trucks reduce GHG emissions by 23% and 8% for city and highway driving, respectively. The results confirm that switching to an HEV fleet could reduce CO₂ emissions during vehicle operations by 25%, as the vehicle manufacturer (Azure Dynamics) has advertised. Moreover, the modeled emission reductions (1,668 t CO₂-eq) and fuel savings (609,000 L) over a distance of 5,200,000 km are similar to Purolator’s advertised values (1,900 t CO₂-eq, 645,000 L). The life-cycle costs of hybrid delivery trucks do not presently make them financially favorable alternatives to conventional diesel trucks, but their financial competitiveness is sensitive to vehicle service life, diesel fuel price, assumed discount rate, and incremental hybrid cost.

Nonparametric Modeling of Vehicle-Type-Specific Headway Distribution in Freeway Work Zones

Abstract: This paper presents a vehicle-type-specific headway distribution analysis in a freeway work zone The goal of this paper is to provide a vehicle-type-specific model with different time periods using empirical work-zone data from highway I-91 in Greenfield, MA A nonparametric approach with a Gaussian kernel is used to describe the vehicle-type-specific headway distribution in a freeway work zone No assumption is required on how the headways should be distributed for nonparametric methods The vehicles are classified into Car, Van, and Truck based on a FHWA vehicle-type classification scheme Statistical tests indicate nonparametric distribution with Gaussian kernel outperforms the lognormal distribution in statistical sense according to the χ2 values Further, another work zone dataset from Jacksonville, FL is utilized to examine the mixed headway scenario without specifying vehicle types The K−S and Chi-square test results suggest the necessity of considering the vehicle types separately Follo

Comparison of Two Simulation Approaches to Safety Assessment: Cellular Automata and SSAM

Abstract: A study is conducted to compare two simulation methods for estimating conflicts between road users. An improved cellular automata (CA) model is proposed to estimate the occurrences and severity of traffic conflicts (both vehicle–vehicle and vehicle–pedestrian) at signalized intersections. The proposed CA model is compared with a calibrated method of a surrogate safety assessment model (SSAM) based on Vissim. Simulated conflicts from both methods are compared with observed vehicle conflicts from automated vehicle tracking for both occurrences and severity. Simulation results show that the CA approach is able to replicate realistic conflicts. However, SSAM tends to overestimate occurrences and underestimate the severity of rear-end and lane-change conflicts. SSAM has also been found to overestimate the severity of crossing conflicts. Furthermore, the proposed CA model is able to estimate conflicts between vehicles and pedestrians.

Development of safety performance measures for urban roundabouts in India

Abstract: Roundabouts, although considered as safe among the various intersection types, have seen an increasing crash rate over the years in India. Geometric design of a roundabout directly influences the driver's speed adoption and maneuvering behavior, and hence plays a vital role in its safety performance. Application of treatments at roundabouts by altering the geometric design requires careful safety evaluation before actual implementation. The present study identified the crash causes and devised safety performance measures for urban roundabouts located in the state of Kerala, India. Crash prediction models and crash modification factors (CMFs) are developed in this study for the safety assessment of geometric design features of roundabouts. Of the many models tried, the zero-inflated negative binomial regression model is the best model to predict the crash frequency of roundabout approaches. Geometric features of the central island, circulatory roadway, and approach roads are associated with the crash occurrence on roundabout approaches. CMFs are developed by a cross-sectional method and are useful for investigating the relationship between safety and geometric design features of roundabouts. Language: en

Operational Advantages of Dynamic Reversible Left-Lane Control of Existing Signalized Diamond Interchanges

Abstract: The signalized diamond interchange is a widely used intersection design for freeway-to-arterial connections. The capacity of these interchanges is largely determined by the number of lanes, the demands of the various movements, the storage spaces for different movements, and the signal-timing strategies. This paper studies the advantages of using dynamic reversible lanes for left-turn movements. In traditional diamond interchanges, the bay lengths cannot change; however, if signal times are adjusted to give more time to an approach when traffic counts are heavier in one direction (such as the shifts between morning and evening peak), this limitation in capacity can be mitigated. In this work, several diamond interchange designs are studied. The optimized traditional diamond interchange performance is compared, in simulation, to the proposed dynamic reversible lane case. Situations are identified in which a dynamic reversible left-lane control would be beneficial in reducing delay and increasing th...

Assessment of Composite Pavement Performance by Survival Analysis

Abstract: The main objective of this paper is to identify the most appropriate rehabilitation method for composite pavements and to evaluate the influence of different factors for the reflective crack development in composite pavement by survival analysis. Four composite pavement rehabilitation methods are evaluated: mill and fill, overlay, heater scarification, and rubblization. Survival analysis is used to evaluate the four methods using three pavement performance indicators: reflective cracking, international roughness index (IRI), and pavement condition index (PCI). Rubblization can significantly retard reflective cracking development compared with the other three methods. No significant difference for PCI is seen in the survival analysis for the four rehabilitation methods. Heater scarification shows the lowest survival probability for both reflective cracking and IRI, whereas overlay results in the poorest overall pavement condition based on PCI. Parametric survival models are employed to further anal...

Unpaved Road Dust Control in the Piceance Creek Basin in Rio Blanco County, Colorado

Abstract: Road dust from unpaved roads (dirt roads) is a major source of airborne particulates; the loss of those fines accelerates the deterioration of roads. As a result, road dust emissions are a major concern of the users and managers of dirt roads. Exxon Mobil has been concerned with the dust emissions and rapid road deterioration of the access roads in its natural gas production facility in the Piceance Creek Basin north of Rifle, Colorado. As part of the access road management plan for Exxon Mobil Piceance Creek, a research project was initiated to investigate the effectiveness of several chemical dust suppressants in reducing dust emissions, thus prolonging the intervals between periodic maintenance. Rio Blanco County and the Bureau of Land Management participated in this project. Using the Colorado State University Dustometer and its associated dust measurement protocol, it was found that all chemical suppressants decrease dust emissions and that magnesium chloride (MgCl2) was the most effective du...

Measuring the Sustainability of Shared-Use Paths: Development of the GreenPaths Rating System

Abstract: The application of sustainable performance measures continues to increase with the development of sustainable rating systems such as leadership in energy and environmental design (LEED), as...

Smart Parking-Management System for Commercial Vehicle Parking at Public Rest Areas

Abstract: Trucks move around 70% of the freight weight in the United States. The combination of increased commercial motor vehicle traffic, tighter delivery schedules, and federally regulated limits on driving time lead to a nationally recognized problem on interstate highways in the United States, i.e., increased demand for commercial truck parking. Unavailability of sufficient parking spaces at rest areas results in illegal and unsafe parking at entrance/exit ramps, and other unauthorized areas. The research reported in this paper, funded by the Florida DOT, sought to understand the truck parking problem in Florida, determine the supply and demand characteristics for commercial truck parking, assess technology that can be used to improve parking management, and conduct a pilot project to test a smart truck parking-management technology to make better utilization of commercial parking spaces at public rest areas.

Street-Crossing Behavior of People with Disabilities

Abstract: Physical disability is as a multifaceted phenomenon, whose manifestations may be difficult to realize and properly address when designing or improving urban built environments. The mere app...

Estimating Welfare Change Associated with Improvements in Urban Bicycling Facilities

Abstract: Prior research has focused on estimating the heath, air quality, safety, and congestion relief benefits of bicycling facilities Bicycling facilities also provide bicyclists with a more enjoyable and safer feeling experience An estimate of the total welfare change, or net benefits, associated with providing improved bicycle facilities should therefore include the value of these additional benefits This study estimates welfare change as willingness to pay (WTP) for improvements in bicycling facilities using several different methods to value travel time Three types of improvements are considered: cycle tracks, bicycle lanes, and street lighting A stated preference survey asked respondents to choose between different levels of bicycle facility improvements and travel time, and also asked respondents for their average and marginal wage rates Cycle tracks were valued the most, followed by street lighting and bicycle lanes Greater cycling experience was associated with lower WPT, although increas