Civil Engineering Commons^™

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a …

Overtime Traffic Enforcement Evaluation: A Methodology For Selecting Agencies And Enforcement Periods, Dario Enrique Romero Santana

Masters Theses

Multiple studies have stated the advantages of police traffic enforcement on crash reduction (Zaidel, February 2002). It is very important to identify locations and time periods where police enforcement produces the greatest crash reductions. The objectives of this study were to: (1) determine the impact of overtime traffic enforcement on crash occurrence; (2) develop procedures to identify police agencies with potential to reduce targeted crashes; and (3) develop procedures to identify additional time periods in which enforcement activities should be conducted. In order to accomplish these objectives, many methodologies were explored. The study used crash and enforcement data collected by …

Lessons From The Green Lanes: Evaluating Protected Bike Lanes In The U.S., Christopher Monsere, Jennifer Dill, Nathan Mcneil, Kelly J. Clifton, Nick Foster, Tara Goddard, Mathew Berkow, Joe Gilpin, Kim Voros, Drusilla Van Hengel, Jamie Parks

Civil and Environmental Engineering Faculty Publications and Presentations

This report presents finding from research evaluating U.S. protected bicycle lanes (cycle tracks) in terms of their use, perception, benefits, and impacts. This research examines protected bicycle lanes in five cities: Austin, TX; Chicago, IL; Portland, OR; San Francisco, CA; and Washington, D.C., using video, surveys of intercepted bicyclists and nearby residents, and count data. A total of 168 hours were analyzed in this report where 16,393 bicyclists and 19,724 turning and merging vehicles were observed. These data were analyzed to assess actual behavior of bicyclists and motor vehicle drivers to determine how well each user type understands the design …

Highway Routine Maintenance Cost Estimation For Nevada, Monika Hagood

UNLV Theses, Dissertations, Professional Papers, and Capstones

State highway agencies are obligated to maintain existing roads for the highway systems to work efficiently and with greater longevity. Every year NDOT is responsible for approximately 13,150 lane miles of existing infrastructure. With that in mind, resources need to be provided to maintain the highway system.

The purpose of this research was to estimate annual routine maintenance cost for several typical treatment methods of highways. Five prioritization categories of highways used by NDOT were considered. Linear regression models were developed that present the relationship between costs including total maintenance cost and five maintenance cost components: labor, equipment, materials, manpower …

Simultaneous Equation Modeling For Crash Rate Of Freeway Segments, Anthony Ramos

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2010, the total number of reported traffic crashes in the state of Nevada was 51,664 of which 235 (0.6%) resulted in one or more deaths (Nevada Department of Transportation, 2012). The state's "Zero Fatalities" traffic safety campaign aims to reduce the rate even further. Out of the total number of crashes, Clark County (includes Las Vegas) accounted for 78.89%. This study examines safety improvement by developing advanced crash prediction models. The system of crash prediction equations consider geometric conditions and traffic volume using simultaneous equation modeling (SEM). The models are based on geometric characteristics and traffic volume data collected …

Generic Incident Model For Investigating Traffic Incident Impacts On Evacuation Times In Large-Scale Emergencies, Andrew J. Collins, Peter Foytik, Erika Frydenlund, R. Michael Robinson, Craig A. Jordan

VMASC Publications

Traffic incidents cause a ripple effect of reduced travel speeds, lane changes, and the pursuit of alternative routes that results in gridlock on the immediately affected and surrounding roadways. The disruptions caused by the secondary effects significantly degrade travel time reliability, which is of great concern to the emergency planners who manage evacuations. Outcomes forecast by a generic incident model embedded in a microscopic evacuation simulation, the Real-Time Evacuation Planning Model (RtePM), were examined to quantify the change in time required for an emergency evacuation that results from traffic incidents. The incident model considered vehicle miles traveled on each individual …

An Explanatory And Comparative Analysis Of Freight Transportation In Eu And U.S. Highways, Luis Alberto Hernandez

Open Access Theses & Dissertations

This thesis provides resources for data collection regarding road freight transportation in the Unites States and the European Union, as well as an explanatory description of data available at each source. Afterwards, individual analysis of the current state of affairs of the highway freight transportation systems in U.S. and EU are performed. Thereafter, an explanatory and comparative analysis between the two land freight transportation systems is performed in terms of regulatory authorities and associations, trucks volume flow, freight weight and volume flow, major issues affecting the system, infrastructure funding sources, and major logistics hubs. Besides, a correlation analysis was performed …

Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke

Civil and Environmental Engineering Faculty Publications and Presentations

Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system …

A Simple Method For Estimation Of Queue Length, S. P. Anusha, Lelitha Devi Vanajakshi, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

Urban arterials are characterized by frequent intersections. Queue length and delay are the two primary measures of performance of intersection. These measures play a primary role in determining the arterial performance. This article presents a methodology to determine the number of vehicles in queue at a signalized intersection for under saturated traffic conditions. The results obtained were validated using actual values that are manually extracted. The root-mean-square error is of the range 1.3 vehicles for estimation of number of vehicles in queue. The various aspects that have to be considered in accurate estimation of performance measures are also discussed.

Performance Comparison Of Design-Build And Construction Manager/General Contractor Highway Projects, Binita Shakya

UNLV Theses, Dissertations, Professional Papers, and Capstones

Researchers have conducted numerous studies comparing project performance of design-bid-build (DBB) and design-build (DB) highway projects. However, little research has been done to compare the performance of DB and construction manager/general contractor (CM/GC) highway projects. Therefore, an exploratory study was conducted to compare the performance of 55 DB and 34 CM/GC highway projects from various States Departments of Transportation (DOTs) in terms of cost, change orders, and construction intensity. The results showed that contract award cost growth was significantly lower in DB projects than in CM/GC projects. In contrast to this, the total cost growth of DB projects was higher …

Developing A Framework For Determining The Contribution Of Transportation Project To Sustainable Development, Karim Ahmed Abdel Warith

Open Access Dissertations

In the past few years, stakeholders in the transportation industry have been concerned with sustainability. However, transportation decision makers have had difficulty incorporating sustainability into transportation infrastructure decisions. This is mainly attributed to the vagueness of the term. Incorporating sustainability into transportation decision making has been a desire put forth by engineers for that past 10 years. However, with no apparent method of defining sustainability, designers and decision makers have not been able to fulfill this desire.

This investigation attempts to define sustainability in a comprehensive and quantitative manner. The research proposes a new methodology that relies on the objective …

Calibration Of Microscopic Traffic Flow Models Considering All Parameters Simultaneously, Victor Hugo Molano Paz

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study proposes a methodology to calibrate microscopic traffic flow simulation models. The proposed methodology has the capability to calibrate simultaneously all the calibration parameters as well as demand patterns for any network topology. These parameters include global and local parameters as well as driver behavior and vehicle performance parameters; all based on multiple performance measures, such as link counts and speeds. Demand patterns are included in the calibration framework in terms of turning volumes.

A Simultaneous Perturbation Stochastic Approximation (SPSA) algorithm is proposed to search for the vector of the model‟s parameters that minimizes the difference between actual and …

Measuring Walkability: Development Of An Automated Sidewalk Quality Assessment Tool, Alexandra Frackelton, Alice Grossman, Evangelos Palinginis, Felipe Castrillon, Vetri Elango, Randall Guensler

Suburban Sustainability

Sidewalks are a critical part of sustainable transportation systems, supporting pedestrian travel and healthy physical activity. Presence and quality of sidewalks is a significant predictor of perceived safety and quality of the pedestrian environment. Lack of adequate pedestrian infrastructure data has been identified as a major barrier to large-scale pedestrian planning. Sidewalk presence, width, and surface condition are identified as important indicators of facility quality and accessibility. Georgia Tech is deploying an Android tablet application to automatically generate spatial sidewalk inventories, automatically assess sidewalk quality, and prioritize sidewalk repairs. The research team has collected field data on sidewalk segments across …

Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Identifying factors that affect crash injury severity and understanding how these factors affect injury severity is critical in planning and implementing highway safety improvement programs. Factors such as driver-related, traffic-related, environment-related and geometric design-related were considered when developing statistical models to predict the effects of these factors on the severity of injuries sustained from motor vehicle crashes at merging and diverging locations. Police-reported crash data at selected freeway merging and diverging areas in the state of Ohio were used for the development of the models. A generalized ordinal logit model also known as partial proportional odds model was applied to …

Partners On Campus: Open Access Transportation Research At Purdue University, David Scherer

Libraries Faculty and Staff Presentations

In the third community webinar presentation on regional and community partnerships, David Scherer, the Scholarly Repository Specialist at Purdue University, described how institutional repositories can support community engagement through the rewards of the partnership between Purdue's institutional repository, Purdue e-Pubs, and Indiana's Joint Transportation Research Program (JTRP). The Purdue Libraries and the Purdue University Press have worked to archive and showcase the fruits of over 75 years of strong collaboration between Purdue University and the Indiana Department of Transportation on research that has a significant impact on the safe and efficient operation of transportation systems throughout Indiana, the United States, …

Investigation Of Crashes And Identifying The Best Practices For Setting Up Speed Zones In Towns Along Rural Highways In Nevada, Krishna Prasad Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2010, 51,664 crashes occurred in Nevada. Only about 9% of those crashes occurred in rural areas of the state. However, if only fatal crashes are considered, 41% of those fatal crashes occurred in rural areas. Generally, speed zones are provided in towns along rural highways to reduce speed-related crashes. However, a guideline is necessary for a consistent procedure to setup speed zones throughout the state. The main objectives of this study are to determine factors associated with crashes and to identify the best practices for setting up speed zones in towns along rural highways.

Eleven towns along rural highways …

An Investigation Of Pavement Distress Variables On Crash Outcomes Using Hierarchical Generalized Linear Regression Modeling, Robert Alan Morgan

Civil & Environmental Engineering Theses & Dissertations

Previous macro-level studies show that the condition of the pavement is associated with roadway safety. However, this premise has not been examined on a micro-level using detailed pavement distress variables (PDVs). The main focus of this research will be to expand the use of the PDV data to further understand the safety risks associated with the type of pavement and each individual PDV by analyzing the likelihood of having a rear-end and/or injurious crash, given that a crash occurs.

Sample crash data and PDV data from the Commonwealth of Virginia for the years 2007 and 2008 were used to produce …

Examining Consumer Behavior And Travel Choices, Kelly J. Clifton, Christopher Devlin Muhs, Sara Morrissey, Tomás Morrissey, Kristina Marie Currans, Chloe Ritter

Civil and Environmental Engineering Faculty Publications and Presentations

This study represents a first attempt to answer a few of the questions that have arisen concerning multimodal transportation investments and the impacts of mode shifts on the business community. This research aims to merge the long history of scholarly work that examines the impacts of the built environment on non-work travel with the relatively new interest in consumer spending by mode of travel. This empirical study of travel choices and consumer spending across 89 businesses in the Portland metropolitan area shows there are important differences between the amounts customers spend on average at various businesses by their mode of …

Path Clearance For Emergency Vehicles Through The Use Of Vehicle-To-Vehicle Communication, Craig Jordan, Mecit Cetin, R. Michael Robinson

VMASC Publications

The study described in this paper evaluated and tested a new strategy to enable emergency response vehicles (EVs) to navigate through congestion at signalized intersections more efficiently. The proposed strategy involves the use of vehicle-to-vehicle communication to send messages to alert vehicles to the approach of the EV and to provide specific instructions on maneuvering to allow the EV to proceed through congested signalized intersections as quickly as possible. This movement is achieved by creation of a split in the vehicle queue in one lane at a critical location to allow the EV to proceed at its desired speed but …

Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari, Pushkin Kachroo, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

In the context of sustainable transportation systems, previous studies have either focused only on the transportation system or have not used a methodology that enables the treatment of incomplete, vague, and qualitative information associated with the available data. This study proposes a system of systems (SOS) and a fuzzy logic modeling approach. The SOS includes the Transportation, Activity, and Environment systems. The fuzzy logic modeling approach enables the treatment of the vagueness associated with some of the relevant data. Performance Indices (PIs) are computed for each system using a number of performance measures. The PIs illustrate the aggregated performance of …

Operational Guidance For Bicycle-Specific Traffic Signals In The United States, Christopher Monsere, Miguel A. Figliozzi, Sam Thompson, Kirk Paulsen

Civil and Environmental Engineering Faculty Publications and Presentations

The research consisted of two phases: 1) a synthesis of practice and 2) and analysis of cyclist performance characteristics. The synthesis of current practice reviewed the literature, current engineering design and operational guidance documents, and surveyed the jurisdictions about their current deployments of bicyclespecific signals. This report summarizes research of cyclist behavior at signalized intersections in Portland, Eugene, Corvallis, Beaverton and Clackamas County, OR. These signals had both bicycle-specific indications and vehicle-only signals. A total of 4,673cyclists were observed. For each cyclist observed arriving on red, a set of descriptive variables were collected (e.g., age, sex, helmet use, presence of …

Demand Responsive Signal Control Strategy (Drsc) Incorporating Queue Length Information In Real-Time Signal Control, Rahul Rajbhara

Civil & Environmental Engineering Theses & Dissertations

Most of the existing vehicle detection systems, namely inductive loops, video cameras etc. are incapable of measuring the queue lengths at signalized intersections. However, with the advent of modern technology, newer detection methods such as probe vehicles equipped with wireless communications (Connected Vehicles), particularly under the Vehicle Infrastructure Integration [52), and radar detection currently provide this capability [53). This thesis presents a Demand Responsive Signal Control Strategy (termed as DRSC) for an isolated signalized intersection. The control strategy incorporates real-time queue length information (obtained from probe vehicles) into the signal control logic. Demand based maximum green time for each upcoming/new …

Analysis Of Primary-Secondary Incident Events On Urban Freeways, Hongbing Zhang

Civil & Environmental Engineering Theses & Dissertations

The objective of this study is to understand the nature of primary and secondary traffic incidents, assess their impacts and explore the implications in traffic operations, safety, and planning. To achieve the objective, a queue-based secondary incident identification method was developed and applied based on detailed incident, traffic and geometric data sets from Hampton Roads, Virginia. This identification method can overcome the limitations in earlier studies and identify secondary incidents in both road directions. An innovative event categorization defines the term "primary-secondary incident event", as one characterized by a primary incident and one or more associated secondary incidents in both …

Spatial Analysis Of Travel Behavior And Response To Traveler Information, Xin Wang

Civil & Environmental Engineering Theses & Dissertations

Transportation planners have long recognized that it is urgent to integrate emerging spatial analysis with travel behavior studies. A clearer understanding of the spatial interactions among travelers and the complex environment they face has the potential to reap benefits of the ongoing technologies of travel behavior, spatial analysis and Advanced Traveler Information Systems (ATIS).

Considering that spatial patterns have been overlooked in the literature of travel behavior and ATIS, the main objective of this research is to use robust methods of spatial analysis to enhance the understanding of how the associations between traveler decisions, built environment and socio-demographic characteristics are …

Integrating Probe Vehicles And Stationary Detector Data To Construct Accurate Cumulative Curves To Study Bottlenecks, Khairul Azfi Anuar

Civil & Environmental Engineering Theses & Dissertations

Advancements in sensors technologies have given researchers and practitioners access to an immense amount of traffic data from multiple types of sensors. However, because of the diversity of the data types, developing a relationship between the different data sources can be challenging. To further complicate the issue, the presence of error or noise makes it difficult to infer any reliable conclusions from the data. To develop a relationship between different data sources, a new methodology is proposed in this thesis for fusing stationary detector data and probe vehicle data to construct an accurate cumulative curve. To remove or to reduce …

Distribution Analysis Of Freight Transportation With Gravity Model And Genetic Algorithm, Jun Duanmu, Peter Foytik, Asad Khattak, R. Michael Robinson

VMASC Publications

The application of a gravity model in freight modeling work on both short-haul and long-haul trips is discussed. A commodity-based gravity model was developed to assess the distribution of freight by long-haul trucks in southeastern Virginia. Although gravity models have been used extensively in transportation studies, little work has been done to address the special characteristics of freight transportation, such as the definition of friction factors and the differences between long-haul and short-haul trips. Results of a recent study of these and similar problems provide valuable insight into freight distribution modeling. A new calibration method that used a genetic algorithm …

Systematic Approach To Evaluate Potential Park And Ride Facilities, Lorenzo Emanuel Cornejo

Open Access Theses & Dissertations

Park and Ride (P&R) facilities promote transit ridership by providing an attractive option to car drivers. They enable potential users to drive to their locations where they can park their cars and take transit services to complete their destinations.

Although the concept of P&R has been implemented in many cities in the United States and integrated with different transportation modes such as mass rapid transit (MRT), light rail transit (LRT), high occupancy vehicle (HOV), Bus Rapid Transit (BRT), among others, no systematic approach has been developed to assess the feasibility of a potential P&R facility. This thesis proposes a systematic …

Analysis Of Isolated Traffic Signal Control Systems, Petr Malina

Open Access Theses & Dissertations

Intelligent Transportation Systems (ITS) are implemented for increase of efficiency and safety in transportation. This thesis focuses on the area of traffic signal timing operations which is one of ITS components. The first objective is to compare the Czech and the U.S. methods for isolated fixed time traffic signal control, using an intersection in El Paso, Texas, as the test site. The second objective of this thesis is to evaluate the U.S. actuated isolated timing plan and compare it against the Czech and U.S. fixed time controls. A microscopic traffic simulation model of the selected intersection is coded in VISSIM …

Evacuee Route Choice Decisions In A Dynamic Hurricane Evacuation Context, R. Michael Robinson, Asad Khattak

VMASC Publications

Very high traffic volumes may lead to extensive congestion during hurricane evacuations. Evacuation planners reduce this congestion by careful planning for multiple hurricane scenarios and assignment of evacuation routes and timing. This planning may be for naught if obstructions block key roadways. An advanced traveler information system (ATIS) may be used to guide evacuees to alternate routes, but how effective will that guidance be? Should the use of alternate routes be encouraged? How are drivers likely to respond to delays and information? Will information shorten or improve the reliability of travel times in emergency conditions? Integration of a dynamic evacuation …

Strategies To Improve And Preserve Flexible Pavements At Intersections, Imad N. Abdallah

Open Access Theses & Dissertations

Many rural intersections originally constructed with thin untreated flexible base and hot mix or a two-course surface treatment experience severe pushing, shoving and rutting. These failures cause an extremely rough surface that can cause damage to small vehicles and potentially cause motorists to lose control of their vehicle. These distresses almost always result in complete failure of the existing pavement that must be repaired several times during the life of the roadway by maintenance forces. Pavement sections constructed with the same materials adjacent to the intersection perform adequately until the approach (approximately 150 ft in advance) of the intersection and …