Civil and Environmental Engineering Commons^™

Collection And Analysis Of 2013-2014 Travel Time Data, Mei Chen, Xu Zhang

Kentucky Transportation Center Research Report

This report documents the findings of Planning Study 27, Collection and Analysis of 2013-2014 Travel Time Data, which is a continuation of Planning Study 24, Analysis of Historical Travel Time Data. The main scope is to analyze newly acquired link-referenced speed data on Kentucky roads from 2013 and 2014.

Results of the analysis demonstrate the value of probe data in measuring and tracking the performance of roadways across several years. In addition, such data can help KYTC and MPOs identify bottlenecks in the network, prioritize improvement strategies, and assess the effectiveness of projects. As data collection techniques advance, …

Benefits From Constructability Reviews, Nikiforos Stamatiadis, Roy Sturgill, Kiriakos Amiridis

Civil Engineering Faculty Publications

Constructability review is a process used during project design to infuse construction knowledge into the design process. There is industry impetus encouraging early construction involvement in project development. State transportation agencies often have to abide by legislation restricting these procurement methods leaving construability review as the only opportunity for early construction involvement. Staffing and budgetary constraints lead to state transportation agencies being very cautious in the practices and processes they implement that seemingly lie outside the main missions of project development and delivery. Without straightforward and documented savings of constructability review processes, these methods may also be eliminated. After streamlining …

Improved Bridge Joint Materials And Design Details, Theodore Hopwood Ii, Christopher W. Van Dyke, Sudhir Palle

Kentucky Transportation Center Research Report

Expansion joints accommodate bridge movements that result from factors such as thermal expansion and contraction, concrete shrinkage, creep effects, live loading, settlement of the foundation and substructure, and environmental stressors. Expansion joints fall into two categories — open joints and closed joints. Open joints contain gaps that facilitate the passage of water and debris runoff through bridge joints. Flexible or stiff troughs are generally installed beneath open joints to direct runoff away from bridge elements. Closed joints produce a watertight seal that inhibits water, debris, and deicing materials from passing through bridge joints and remaining in contact with underlying bridge …

Subcontracting And The Survival Of Plants In The Road Construction Industry: A Panel Quantile Regression Analysis, Dakshina G. De Silva, Georgia Kosmopoulou, Carlos Lamarche

Economics Faculty Publications

This paper investigates how subcontracting parts of contracted work shapes entrants’ success and survival. We find that newly developed quantile regression approaches can be adapted to study survival of firms competing for government contracts in road construction. The method is applied on a data set that includes patterns of firm entry, exit and auction related information. We find an apparent increase in the business life of firms who subcontract out part of their projects. In Texas, these subcontracting effects appear to be more pronounced for firms with few or no options outside the industry, and among firms who contract out …

Oxidation Of Substituted Catechols At The Air-Water Interface: Production Of Carboxylic Acids, Quinones, And Polyphenols, Elizabeth A. Pillar, Marcelo I. Guzman

Chemistry Faculty Publications

Anthropogenic activities contribute benzene, toluene, and anisole to the environment, which in the atmosphere are converted into the respective phenols, cresols, and methoxyphenols by fast gas-phase reaction with hydroxyl radicals (HO(•)). Further processing of the latter species by HO(•) decreases their vapor pressure as a second hydroxyl group is incorporated to accelerate their oxidative aging at interfaces and in aqueous particles. This work shows how catechol, pyrogallol, 3-methylcatechol, 4-methylcatechol, and 3-methoxycatechol (all proxies for oxygenated aromatics derived from benzene, toluene, and anisole) react at the air-water interface with increasing O3(g) during τc ≈ 1 μs contact time and contrasts their …

In-Service Evaluation Of High Tension Cable Barrier Systems, Brian K. Howell, Kenneth R. Agent, Jeff Jasper, William Nicholas Staats

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet has installed hundreds of miles of high-tension cable median barrier (CMB) as a safety innovation. The usage of CMB aids in the prevention of crossover crashes, where a vehicle departs the roadway on the left shoulder, crosses the median, and enters the opposing lane(s) of traffic. KYTC officials have questioned whether all three barrier products perform similarly. Some installed cable barrier systems have lost tension across the entire cable length after a single vehicle impact. If a second vehicle were to strike the cable barrier system in a location other than the damaged area of the …

Analysis Of Autonomous Vehicle Policies, Bryan Gibson

Kentucky Transportation Center Research Report

The rapid development and adoption of connected and autonomous vehicles will transform the U.S. transportation system over the next 30 years. Although the widespread use of fully connected and autonomous vehicles is still several years away, it is nonetheless critical that legislators, policymakers, and regulators understand how the presence of these vehicles will restructure the operation of roadway networks. Without a doubt, lawmakers and policymakers will need to develop new laws — and revise existing ones — to account for the presence of connected and autonomous vehicles. This report provides an overview of connected and autonomous vehicles — their positives …

Development Of A Research Project Tracking System, Joseph D. Crabtree, Bradley A. Rogers

Kentucky Transportation Center Research Report

The Kentucky Transportation Center, in cooperation with the Kentucky Transportation Cabinet, has developed a Research Project Tracking System (RPTS). The RPTS is web-based and includes a database of active (and recently completed) research projects. The system allows authorized users to access and edit the project data, enter new projects into the system, and produce periodic progress reports. It produces a homepage (or dashboard) for each project, and it provides links to key project documents. It also has the capability to track the implementation of research results on a project-by-project basis.

A Programmatic Approach To Long-Term Bridge Preventive Maintenance, Danny Wells, Bobby W. Meade, Theodore Hopwood Ii, Sudhir Palle

Kentucky Transportation Center Research Report

State transportation agencies use cost-effective preventive maintenance (PM) programs to preserve existing roadway systems, slow down their deterioration, and improve their functional condition. Currently, KYTC’s bridge inventory includes approximately 10,000 structures, and by 2018, most of these structures will have been in use for at least 50 years. Because there is insufficient funding available to pursue a large-scale bridge replacement program, it is critical for the Cabinet to prolong the lives of its bridges by using economical strategies. This report provides guidance that the Kentucky Transportation Cabinet (KYTC) can use to develop and implement a statewide bridge PM program. Drawing …

Air Exchange Rates And Alternatuve Vapor Entry Pathways To Inform Vapor Intrusion Exposure Risk Assessments, Rivka Reichman, Mohammadyousef Roghani, Evan J. Willett, Elham Shirazi, Kelly G. Pennell

Civil Engineering Faculty Publications

Vapor intrusion (VI) is a term used to describe indoor air (IA) contamination that occurs due to the migration of chemical vapors in the soil and groundwater. The overall vapor transport process depends on several factors such as contaminant source characteristics, subsurface conditions, building characteristics, and general site conditions. However, the classic VI conceptual model does not adequately account for the physics of airflow around and inside a building and does not account for chemical emissions from alternative “preferential” pathways (e.g. sewers and other utility connections) into IA spaces. This mini-review provides information about recent research related to building air …

Nitrate Radicals And Biogenic Volatile Organic Compounds: Oxidation, Mechanisms And Organic Aerosol, Nga Lee Ng, Steven S. Brown, Alexander T. Archibald, Elliot Atlas, Ronald C. Cohen, John N. Crowley, Douglas A. Day, Neil M. Donahue, Juliane L. Fry, Hendrik Fuchs, Robert J. Griffin, Marcelo I. Guzman, Hartmut Hermann, Alma Hodzic, Yoshiteru Iinuma, José L. Jimenez, Astrid Kiendler-Scharr, Ben H. Lee, Deborah J. Luecken, Jingqiu Mao, Robert Mclaren, Anke Mutzel, Hans D. Osthoff, Bin Ouyang, Benedicte Picquet-Varrault, Ulrich Platt, Havala O. T. Pye, Yinon Rudich, Rebecca H. Schwantes, Manabu Shiraiwa, Jochen Stutz, Joel A. Thornton, Andreas Tilgner, Brent J. Williams, Rahul A. Zaveri

Chemistry Faculty Publications

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO₃) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO₃-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol. Despite its long history of research and the significance of this topic in atmospheric chemistry, a number …

Develop A Highway Inventory Data Quality Control Scheme (Pl-26), Mei Chen, Obaidur Rahman Kazi, Tony Fields

Kentucky Transportation Center Research Report

Since passage of the Moving Ahead for Progress in the 21st Century (MAP-21), transportation agencies have become increasingly reliant on data for planning and programming, asset management, and performance tracking. An efficient asset inventory database with accurate data is critical for states to comply with MAP-21 (and now FAST Act) requirements.

The Kentucky Transportation Cabinet’s (KYTC) Division of Planning maintains the Highway Information System (HIS), which is a primary source of this information for transportation professionals at the Cabinet (KYTC). Because highway system is continually changing, it is a challenging task to keep the information in the HIS up to …

Us Residential Building Air Exchange Rates: New Perspectives To Improve Decision Making At Vapor Intrusion Sites, Rivka Reichman, Elham Shirazi, Donald G. Colliver, Kelly G. Pennell

Civil Engineering Faculty Publications

Vapor intrusion (VI) is well-known to be difficult to characterize because indoor air (IA) concentrations exhibit considerable temporal and spatial variability in homes throughout impacted communities. To overcome this and other limitations, most VI science has focused on subsurface processes; however there is a need to understand the role of aboveground processes, especially building operation, in the context of VI exposure risks. This tutorial review focuses on building air exchange rates (AERs) and provides a review of literature related building AERs to inform decision making at VI sites. Commonly referenced AER values used by VI regulators and practitioners do not …

Kentucky Vehicle License Plate Study, Valerie J. Keathley, Andrew Martin, Jerry Kissick, Gray Forlines, Jennifer R. Walton

Kentucky Transportation Center Research Report

This study assesses Kentucky’s options for potentially re-plating all motor vehicles registered in the Commonwealth. The report begins with a background and discussion of Kentucky’s plate production processes, the difference between flat and embossed plates, and the structure of license plate labor at the Kentucky State Reformatory in La Grange. It details current plate production costs and processes, along with fees and production numbers. It evaluates three scenarios for future plate production: flat plate production, a hybrid system with embossed general issue plates and flat specialty plates, and an embossed plate system with in-house printed sheeting. Also included is an …

Fate And Impacts Of Priority Pollutant Metals In Coal Fly Ash–Soil–Switchgrass Plant Mesocosms, Olushola M. Awoyemi, E. Kudjo Dzantor

Coal Combustion and Gasification Products Journal Archive

Coal fly ash (CFA) is a coal combustion by-product containing heavy metals (HMs) that can enter and accumulate in environmental matrices. The current study assessed the fate and effects of HMs contained in CFA on Armour silt loam (ASL) soil, switchgrass plant, and leachate. Soil impact indices compared levels of HMs in the CFA-soil admixtures to control soil (without CFA). These indices include contamination factor (*C*~f~), modified degree of contamination (m*C*~d~), and pollution load index (PLI). The ratio of the levels of HMs in switchgrass root and shoot tissues to their levels in the CFA-soil admixtures were used to determine …

Sediment Transport Modelling Using Dynamic (Dis)Connectivity Prediction For A Bedrock Controlled Catchment, David Tyler Mahoney

Theses and Dissertations--Civil Engineering

The (dis)connectivity of sediment, defined as the detachment and transport of sediment from source to sink between geomorphic zones, is a major control on sediment transport rates but has seldom taken precedence in sediment transport models that focus on assessment of sediment impacts on water supply. A watershed-scale sediment transport model was formulated that incorporates sediment (dis)connectivity knowledge and subroutines and predicts sediment flux through coupling with an excessive shear stress erosion equation. The intersecting probabilities of sediment supply, detachment, transport, and (dis)connectivity produce the probability of sediment connectivity for a watershed or region of a watershed. The integration of …

Transportation Network Companies: Influencers Of Transit Ridership Trends, Richard A. Mucci

Theses and Dissertations--Civil Engineering

The major transit systems operating in San Francisco are San Francisco Municipal (MUNI), Bay Area Rapid Transit (BART), and Caltrain. The system of interest for this paper is MUNI, in particular the bus and light rail systems. During the past decade transit ridership in the area has experienced diverging growth, with bus ridership declining while rail ridership is growing significantly (Erhardt et al. 2017). Our data show that between 2009 and 2016, MUNI rail ridership increases from 146,000 to 171,400, while MUNI bus ridership decreases from 520,000 to 450,000. Direct ridership models (DRMs) are used to determine what factors are …

Prediction Of Protected-Permissive Left-Turn Phasing Crashes Based On Conflict Analysis, Shraddha Sagar

Theses and Dissertations--Civil Engineering

Left-turning maneuvers are considered to be the highest risk movements at intersections and two-thirds of the crashes associated with left-turns are reported at signalized intersections. Left-turning vehicles typically encounter conflicts from opposing through traffic. To separate conflicting movements, transportation agencies use a protected-only phase at signalized intersections where each movement is allowed to move alone. However, this could create delays and thus the concept of a protected-permissive phase has been introduced to balance safety and delays. However, the permissive part of this phasing scheme retains the safety concerns and could increase the possibility of conflicts resulting in crashes. This research …

Self-Sensing Cementitious Materials, Alexander Nicholas Houk

Theses and Dissertations--Civil Engineering

The study of self-sensing cementitious materials is a constantly expanding topic of study in the materials and civil engineering fields and refers to the creation and utilization of cement-based materials (including cement paste, cement mortar, and concrete) that are capable of sensing (i.e. measuring) stress and strain states without the use of embedded or attached sensors. With the inclusion of electrically conductive fillers, cementitious materials can become truly self-sensing. Previous researchers have provided only qualitative studies of self-sensing material stress-electrical response. The overall goal of this research was to modify and apply previously developed predictive models on cylinder compression test …

Geopolymerization Of Coal Ash To Produce Cementless Binders, Hamid Akbari, Robert Mensah-Biney, Jonathan Simms

Coal Combustion and Gasification Products Journal Archive

The main objective of this study was to evaluate geopolymer concrete made from coal combustion by-products, disposed of in landfills, as a potential substitute for the ordinary Portland cement (OPC), which is responsible for 5-8% of the total CO2 emissions in the world. In this study, a coal fly ash sample from the Carolinas was used in a chemical process known as geopolymerization to produce a “geopolymer” binder. The developed geopolymer binder could competently substitute the OPC binder in regular concrete applications. An experimental design program was conducted to optimize parameters of the geopolymerization affecting the strength of the final …

Groundwater Monitoring And Data Analysis Under The Coal Combustion Residuals Rule, Bruce Hensel

Coal Combustion and Gasification Products Journal Archive

No abstract provided.

Ponded And Landfilled Fly Ash As A Source Of Rare Earth Elements From A Kentucky Power Plant, James C. Hower, John G. Groppo, Kevin R. Henke, Uschi M. Graham, Madison M. Hood, Prakash Joshi, Dorin V. Preda

Coal Combustion and Gasification Products Journal Archive

Twenty samples, with one composite sample built out of the 20 individual samples, of ponded ash were collected at a Kentucky power plant. The coal feed throughout the history of the power plant was central eastern Kentucky low- to moderate-S high volatile A bituminous coal. The pond was in the process of being excavated, with the ash moved to a landfill on another company property. In spite of the long history of the pond and the expected variation in coal supply, and perhaps because of the mixing due to the excavation, there is little variation in ash-basis rare earth elements …

Rare Earth Element Distribution In Fly Ash Derived From The Fire Clay Coal, Kentucky, Madison M. Hood, Ross K. Taggart, Ryan C. Smith, Heileen Hsu-Kim, Kevin R. Henke, Uschi Graham, John G. Groppo, Jason M. Unrine, James C. Hower

Coal Combustion and Gasification Products Journal Archive

Fly ash was collected from individual mechanical and electrostatic precipitator (ESP) hoppers at a 130-MW pulverized-coal utility unit burning a southeastern Kentucky moderate- to high-S Pennsylvanian Fire Clay coal. The fly ash particle size is generally similar within each row of the mechanical and ESP hoppers, with the mean particle diameter decreasing from >36 μmin the mechanical hoppers to 6 μm in the last ESP row. Rare earth element (REE)–bearing phases occur within fine minerals and, possibly, as part of the fly ash glass phase. Transmission electron microscopy was used to identify Y-Ce-Nd-La–bearing regions within a glassy matrix. Y- and …

The Relative Impact Framework For Evaluating Coal Combustion Residual Surface Impoundment Closure Options: Applications And Lessons Learned, Ari S. Lewis, Andrew B. Bittner

Coal Combustion and Gasification Products Journal Archive

In response to the U.S. Environmental Protection Agency’s new rule regarding the disposal of coal combustion residuals (CCRs), many utilities need to re-examine their waste disposal practices and make decisions regarding if and how unlined surface impoundments (SIs) should be closed. The two primary options for closing SIs are in-place closure, with capping and engineering controls, and excavation of the CCR for transport to and re-disposal in a lined landfill. To help inform closure option decisions, we supported the Electric Power Research Institute’s development of a practical, science-based decision framework that comprehensively evaluates the potential impacts to human health and …

Kentucky Traffic Collision Facts 2016, Eric R. Green, Paul A. Ross, Christopher L. Blackden, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC COLLISION FACTS report is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statutes 189.635, “every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize data on traffic collisions for such purposes as will improve the traffic safety program in the Commonwealth. Data contained in this report are based solely on the observations and judgements …

The Impact Of Owner Practices And Procedures On Construction Project Safety Performance, Huang Liu

Theses and Dissertations--Civil Engineering

Construction sites are dangerous work environments. One traditional assumption prevails in the construction industry that construction safety should be the sole responsibility of the contractor. However, some safety researchers gradually begin to challenge this assumption. The elementary research in this field try to validate the existence of relationship of the owner’s practices and safety performance, which indicates that the involvements of the owner have a positive impact on improvement of safety performance. Therefore, the owner can and should take a responsibility of the project safety. Some subsequent research focus on collecting and summarizing the best safety practices and procedures of …

Safety-Based Guidelines For Left-Turn Phasing Decisions With Negative Binomial Regression, Kiriakos Amiridis

Theses and Dissertations--Civil Engineering

The efficient and safe movement of traffic at signalized intersections is the primary objective of any signal phasing and timing plan. Accommodation of left turns is more critical due to the higher need for balancing operations and safety. The objective of this study is to develop models to estimate the safety impacts of the use of left-turn phasing schemes. The models are based on data from 200 intersections in urban areas in Kentucky. For each intersection, approaches with a left-turn lane were isolated and considered with their opposing through approach in order to examine the left-turn related crashes. This combination …

Pavement Condition Index And Cost Of Ownership Analysis On Preventative Maintenance Projects In Kentucky, Dominic J. Michels

Theses and Dissertations--Civil Engineering

The Commonwealth of Kentucky has seen increasing use over time of preventative maintenance treatments on its asphalt pavements. Performance of two of the most prevalent treatments employed by the Kentucky Transportation Cabinet (KYTC) – Thin Asphalt Overlay (Thinlay) and Microsurfacing – had yet to be examined in-depth through condition surveys. This thesis describes the data collection process to find the Pavement Condition Index (PCI) of each preventative maintenance site in Kentucky from the last 10 years. With PCI from each site, deterioration curves were generated for each treatment – providing the estimated life extension benefit of each. The analysis then …

Incorporating Travel Time Reliability Into Transportation Network Modeling, Xu Zhang

Theses and Dissertations--Civil Engineering

Travel time reliability is deemed as one of the most important factors affecting travelers’ route choice decisions. However, existing practices mostly consider average travel time only. This dissertation establishes a methodology framework to overcome such limitation.

Semi-standard deviation is first proposed as the measure of reliability to quantify the risk under uncertain conditions on the network. This measure only accounts for travel times that exceed certain pre-specified benchmark, which offers a better behavioral interpretation and theoretical foundation than some currently used measures such as standard deviation and the probability of on-time arrival.

Two path finding models are then developed by …

Analytical Strip Method For Thin Cylindrical Shells, John T. Perkins

Theses and Dissertations--Civil Engineering

The Analytical Strip Method (ASM) for the analysis of thin cylindrical shells is presented in this dissertation. The system of three governing differential equations for the cylindrical shell are reduced to a single eighth order partial differential equation (PDE) in terms of a potential function. The PDE is solved as a single series form of the potential function, from which the displacement and force quantities are determined. The solution is applicable to isotropic, generally orthotropic, and laminated shells. Cylinders may have simply supported edges, clamped edges, free edges, or edges supported by isotropic beams. The cylindrical shell can be stiffened …