Civil Engineering Commons^™

Roadway Determinants Of Bicyclist Multi-Pollutant Exposure Concentrations, Alexander Y. Bigazzi, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Due to poorly quantified traffic-exposure relationships, transportation professionals are unable to easily estimate exposure differences among bicycle routes for network planning, design, and analysis. This paper estimates the effects of roadway characteristics on bicyclist multi-pollutant exposure concentrations, controlling for meteorology and background conditions. Concentrations of volatile organic compounds (VOC), carbon monoxide (CO), and fine particulate matter (PM2.5) are modeled using high-resolution on-road data. This paper also compares exposure differences on immediately parallel high-traffic/low-traffic facilities and is the first study to quantify VOC exposure differences by facility. Results indicate that average daily traffic (ADT) provides a parsimonious way to characterize the …

Dynamic Ventilation And Power Output Of Urban Bicyclists, Alexander Y. Bigazzi, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Bicyclist intake of air pollutants is linked to physical exertion levels, ventilation rates, and exposure concentrations. Whereas exposure concentrations have been widely studied in transportation environments, there is relatively scant research linking on-road ventilation with travel conditions and exertion levels. This paper investigates relationships among power output, heart rate, and ventilation rate for urban bicyclists. Heart rate and ventilation rate were measured on-road and combined with power output estimates from a bicycle power model. Dynamic ventilation rates increased by 0.4-0.8% per watt of power output, with a mean lag of 0.8 minutes. The use of physiology (ventilation) monitoring straps and …

Empirical Analysis Of Bus Bunching Characteristics Based On Bus Avl/Apc Data, Wei Feng, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Bus bunching takes place when headways between buses are irregular. Bus bunching is associated with longer waiting times for riders, overcrowding in some buses, and an overall decrease on the level of service and capacity. Understanding the temporal and spatial characteristics and the causes and effects of bus bunching incidents from archived bus data can greatly aid transit agencies to develop efficient mitigation strategies. This paper presents methods to identify and visualize specific time periods and segments where bus bunching incidents occur based on automatic vehicle location (AVL) and automatic passenger count (APC) data. The paper also proposes methods that …

Does The Bicycle Detector Symbol Change Cyclist Queuing Position At Signalized Intersections?, Stefan W. Bussey, Christopher M. Monsere, Peter Koonce

Civil and Environmental Engineering Faculty Publications and Presentations

The Manual of Traffic Control Devices (MUTCD) includes a bicycle detector pavement marking (Section 9C-05) and accompanying explanatory sign (R10-22) which may encourage cyclists to position themselves over detection at traffic signals. This paper presents the results of an observational and survey- based study evaluating the bicycle detector marking. Three minor actuated approaches at signalized intersections with significant bicycle volumes and without bicycle detector markings were selected for treatment. Three configurations were compared: 1) bicycle detector marking only 2) bicycle detector marking with the R10-22 explanatory sign, and 3) an alternative bicycle detector installed over a contrasting green rectangle. Analysis …

Exploring Thresholds For Timing Strategies On A Pedestrian Active Corridor, Sirisha Murthy Kothuri, Peter Koonce, Christopher M. Monsere, Titus Reynolds

Civil and Environmental Engineering Faculty Publications and Presentations

Traditional signal timing policies have typically prioritized vehicles over pedestrians at intersections, leading to undesirable consequences such as large delays and risky crossing behaviors. The objective of this paper is to explore signal timing control strategies to reduce pedestrian delay at signalized intersections. The impacts of change in signal controller mode of operation (coordinated vs. free) at intersections were studied using the micro-simulation software VISSIM. A base model was developed and calibrated for an existing pedestrian active corridor. A hypothetical network of three intersections was used to explore the effects of mode of operation and measures of delay for pedestrians …

Creating A National Nonmotorized Traffic Count Archive: Process And Progress, Krista Nordback, Kristin A. Tufte, Morgan Harvey, Nathan Mcneil, Elizabeth Stolz, Jolene Liu

Civil and Environmental Engineering Faculty Publications and Presentations

Robust bicycle and pedestrian data on a national scale would help promote effective planning and engineering of walking and bicycling facilities, build the evidence-based case for funding such projects, and dispel notions that walking and cycling are not occurring. To organize and promote the collection of nonmotorized traffic data, a team of transportation professionals and computer scientists is creating a national bicycle and pedestrian count archive. This archive will enable data sharing by centralizing continuous and short-duration traffic counts in a publicly available online archive. Although other archives exist, this will be the first archive that will be national in …

Evolution And Usage Of The Portal Data Archive: 10-Year Retrospective, Kristin A. Tufte, Robert Bertini, Morgan Harvey

Civil and Environmental Engineering Faculty Publications and Presentations

The Portal transportation data archive (http://portal.its.pdx.edu/) was begun in June 2004 in collaboration with the Oregon Department of Transportation, with a single data source: freeway loop detector data. In 10 years, Portal has grown to contain approximately 3 TB of transportation-related data from a wide variety of systems and sources, including freeway data, arterial signal data, travel times from Bluetooth detection systems, transit data, and bicycle count data. Over its 10-year existence, Portal has expanded both in the type of data that it receives and in the geographic regions from which it gets data. This paper discusses the …

Bottom Friction Assessment For Hydrodynamic Currents In The Lower St. Johns River, Henok Kefelegn Demissie

UNF Graduate Theses and Dissertations

A preexisting version of the 2D finite-element hydrodynamic model (code) ADCIRC was modified to enable assimilation of velocity data for calculation of longwave hydrodynamics of the lower St. Johns River. The data assimilation also enables model calibration and parameter estimation of directionally variant Manning’s n value using an anisotropic formulation of bottom roughness. This modified version of the ADCIRC code differs from the original ADCIRC model, as it introduces a module to provide evaluation of directional Manning’s roughness coefficient using observed velocity data for ebb and flood flow durations. The vector-based directional Manning’s n value is found by comparing the …

Comparison Of Hydrologic Model Performance Statistics Using Thiessen Polygon Rain Gauge And Nexrad Precipitation Input Methods At Different Watershed Spatial Scales And Rainfall Return Frequencies, Amanda E. Tancreto

UNF Graduate Theses and Dissertations

As hydrological computer modeling software continues to increase in complexity, the need for further understanding of the value of different model input datasets becomes apparent. Frequently used precipitation model input include rain gauge data and next-generation radar–based (NEXRAD) rainfall data. Rain gauge data are usually interpolated across a model domain using various methods including the Thiessen Polygon methodology, which may be data-sparse in some areas and overly data-dense in others. However, rain gauge data are generally very easy to use in hydrologic model development, often requiring little to no data processing. NEXRAD data have the potential to improve hydrologic runoff …

Effect Of Lateral Stiffness On Bridge Deck Performance, Andrea Del Pilar Toro

UNF Graduate Theses and Dissertations

The use of the empirical deck design method has increased its acceptance due to the economic advantages that it presents when compared to its counterpart, the traditional method. This can be attributed to the fact that the empirical method provides an appropriate design where the deck withstands stress not only due to the steel reinforcement but to an implicit arching membrane stress set-up as an effect of the lateral restraint surrounding the deck slab known as Compressive Membrane Action (CMA).

It has been proved through research that most design codes underestimate the strength of laterally restrained slabs. However, there is …

The Development Of A Hydrodynamics-Based Storm Severity Index, Gabriel Francis Todaro

UNF Graduate Theses and Dissertations

A hydrodynamic-based storm severity scale that ranks the damage potential of a storm at a given coastal area is developed. Seventeen tropical and extratropical storm events at 113 different locations on the Atlantic coast and the Gulf of Mexico are examined in order to create and verify a Storm Severity Index Model (SSIM). The results from the SSIM are then used to create a location-based storm severity scale titled the Twenty-Four Point Storm Severity Scale. The Twenty-Four Point Scale is based on three subsets of factors. The first is the energy flux above the normal mean high water line that …

Earthmoving Productivity In Urban Bridge Construction, Seonghoon Kim, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

Earthmoving operations in urban bridge reconstruction projects are analyzed to identify significant factors that impact relatively low productivity. The research project was conducted in the urban interchange reconstruction of Interstate Highway 235 (I-235) in Des Moines, Iowa. By using observational studies and a statistical analysis method, the factors were identified, including match factor, number of passes, and loading cycle time per bucket. Number of truck, match factor, travel time, and hauling distance were identified as the unique factors for the off-site earthmoving project, while the start time and travel time were significant factors for the on-site project. This research also …

Performance-Based Engineering For Evaluation And Retrofitting Non-Ductile Reinforced Concrete Buildings Incorporating Aftershock Hazard, Ruilong Han

Dissertations, Master's Theses and Master's Reports - Open

Performance-based engineering (PBE) provides a probabilistic tool for assessing the seismic risk and performance of buildings. Only the mainshock hazard has been included in the current PBE framework, although the concern on aftershock hazard has been increased recently. This study develops methodologies to incorporate aftershock hazard into a PBE framework, and assesses the seismic risk and performance of non-ductile reinforced concrete (RC) frame buildings under mainshock and aftershock hazards. A seismic retrofit strategy for these buildings, base isolation, is also evaluated using the developed methodologies.

A methodology for synthesizing aftershock ground motions is proposed and validated to resolve the challenge …

Numerical Study Of Structural Responses Of Rigid And Flexible Pavements Under Heavy Vehicles’ Loading, Rezwana Kabir

Dissertations, Master's Theses and Master's Reports

The highway system serves as the most critical transportation link in the economic development of a nation. In Michigan, about 74% of all the commodities delivered annually are transported by heavy trucks. The Michigan Department of Transportation (MDOT) permits multi-axle (11 axles) heavy truck with gross vehicle weight (GVW) limit of 164,000 lb., unlike many states having GVW limit of 80,000 lb. The effect of these heavy truck loadings on pavements might accelerate the rate of deterioration for flexible and rigid pavement structures. More detailed knowledge of the interaction of trucks with the pavement structure is essential for better management …

Development Of An Automated Method For Identification Of Wet And Dry Channel Segments Using Lidar Data And Fuzzy Logic Cluster Analysis, Chris Rowney

Electronic Theses and Dissertations

Research into the use of LiDAR data for purposes other than simple topographic elevation determination, such as urban land cover classification and the identification of forest biomass, has become prominent in recent years. In many cases, alternative analysis methodologies conducted using airborne LiDAR data are possible because the raw data collected during a survey can include information other than the classically used elevation and coordinate points, the X, Y, and Z of the plane. In particular, intensity return values for each point in a LiDAR grid have been found to provide a useful data set for wet and dry channel …

Road Management System And Road Safety In Uganda, Paul Gudoi Zanule

Walden Dissertations and Doctoral Studies

Traffic collisions cost Uganda millions of dollars each year. The purpose of this descriptive case study was to describe the strategies and processes needed to implement a road management system. Such a system would significantly reduce the fatalities and accidents in Uganda, improve the transportation within Kampala's business district, and increase business profitability. Three conceptual theories framed the research study: management theory, strategic management theory, and criminology theory. Using a snowball sampling strategy, data were collected from open-ended interviews, questionnaires, observations, and archived documents from 20 administrative participants in the government and organizational leaders involved in the transport operations and …

Quantifying Benefits Of Signal Timing Maintenance And Optimization Using Both Travel Time And Travel Time Reliability Measures, Howell Li, Steven M. Lavrenz, Christopher M. Day, Amanda Stevens, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

High-Resolution Controller Data Performance Measures For Optimizing Diverging Diamond Interchanges And Outcome Assessment With Drone Video, Alexander M. Hainen, Amanda L. Stevens, Christopher M. Day, Howell Li, Jamie Mackey, Matt Luker, Mark Taylor, James R. Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Characterizing Signalized Intersection Performance Using Maximum Vehicle Delay, Steven M. Lavrenz, Christopher M. Day, Alexander M. Hainen, W Benjamin Smith, Amanda L. Stevens, Howell Li, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Sequence Optimization At Signalized Diamond Interchanges Using High-Resolution Event-Based Data, Alexander M. Hainen, Howell Li, Amanda L. Stevens, Christopher M. Day, Jim Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.