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Prospects For Meeting The Corporate Average Fuel Economy Standards In The U.S., Jessica Zielinski, Rebecca Andreucci, Can B. Aktas 2016 University of New Haven

Prospects For Meeting The Corporate Average Fuel Economy Standards In The U.S., Jessica Zielinski, Rebecca Andreucci, Can B. Aktas

Civil Engineering Faculty Publications

In 2013, the transportation sector accounted for 34% of the United States’ greenhouse gas emissions, with no significant change from prior years. Efforts to improve vehicle transportation efficiency and curb associated environmental emissions had led to the Corporate Average Fuel Economy (CAFE) standards for passenger cars and light trucks initially introduced in 1975. The National Highway Traffic Safety Administration has phased in new standards recently that require an average combined fleetwide fuel economy of 35.1 - 35.4 mpg by 2017, 40.3 - 41.0 mpg by 2021, and 48.7 - 49.7 mpg by 2025. The new legislation has the potential to …


Evaluating A New Cem Iii/A Cement For Concretes Exposed To Harsh Acid Rich Environments, David Thompson, Niall Holmes, John Reddy 2016 Technological University Dublin

Evaluating A New Cem Iii/A Cement For Concretes Exposed To Harsh Acid Rich Environments, David Thompson, Niall Holmes, John Reddy

Conference papers

The Irish Annex to the European specification, performance, production and conformity of concrete, IS EN 206, recommends CEM III/B cement for acid rich environments containing between 66 to 80% GGBS. However, BS 8500, the UK annex to EN 206 and the British Research Establishment (BRE) Special Digest 1, recommends CEM III/A cement with a GGBS range of 36-65%. This project investigated the performance of a new CEM III/A cement produced by Ecocem Ireland in concretes exposed to such environments using an extensive suite of laboratory tests.

In Ireland, up to €5.8bn will be invested to provide fresh drinking water and …


Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim 2016 University of Central Florida

Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim

Electronic Theses and Dissertations

This dissertation investigates the hydroclimatic controls on drainage network dynamics and characterizes the variation of drainage density in various climate regions. The methods were developed to extract the valley and wet channel networks based on Light Detection and Ranging (LiDAR) data including the elevation and intensity of laser returns. The study watersheds were selected based on the availability of streamflow observations and LiDAR data. Climate aridity index was used as a quantitative indicator for climate. The climate controls on drainage density were re-visited using watersheds with minimal anthropogenic interferences and compared with the U-shape relationship reported in the previous studies. …


Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby 2016 University of Central Florida

Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby

Electronic Theses and Dissertations

Fog along roadways is a dangerous hazard that leads to crashes resulting from limited visibility. Low visibility gives drivers less time to react to potential obstacles that can suddenly appear and require immediate action. To solve this issue, early warning systems involving Dynamic Message Signs or other types of devices are used to alert drivers of the impending visibility condition so that they are prepared. This research focuses on testing the effectiveness of one form of warning systems to investigate how it impacts driver behavior in foggy conditions. To accomplish this objective, a simulation study is developed to test variables …


The Behavior Of Simply Supported Plates Under Extreme Shear Loading, Mhd ammar Hafez 2016 Cleveland State University

The Behavior Of Simply Supported Plates Under Extreme Shear Loading, Mhd Ammar Hafez

ETD Archive

Steel plates are planar structural elements with one dimension significantly smaller than the others. These elements may fail due to either material yielding or buckling. Buckling is a sudden failure mode, which is not desirable in structural engineering applications. Buckling is called an “elastic buckling” when it happens before material yielding, and is termed as “plastic buckling” if it happens after material yielding. The focus of this thesis is on shear plates, which are plates that are primarily subjected to shear loads. Several studies were conducted to increase the elastic buckling capacity of plates by adding stiffeners to plates. However, …


Toward A Better Estimation Of Shear Capacity And Structural Reliability Of Prestressed Concrete Girders, Alaa Ibrahim Chehab 2016 Wayne State University

Toward A Better Estimation Of Shear Capacity And Structural Reliability Of Prestressed Concrete Girders, Alaa Ibrahim Chehab

Wayne State University Dissertations

The main objectives of this study are to evaluate the adequacy of the current AASHTO methods for shear design of prestressed concrete (PC) bridge girders, determine the reliability of PC bridge girders in shear based on the current LRFD General Procedure, determine the most accurate and consistent method for predicting the shear capacity of AASHTO “I” shape PC bridge girders, and recalibrate the AASHTO LRFD code for shear as necessary. These objectives were achieved through lab testing of two full scale Type II girders, finite element modeling for more than 330 PC girders, parametric analysis, regression analysis, and structural reliability …


Kinetic Energy Harvesting Mechanism For Vortex Drop Structures, Mungtra Chusilp 2016 Louisiana Tech University

Kinetic Energy Harvesting Mechanism For Vortex Drop Structures, Mungtra Chusilp

Doctoral Dissertations

Energy recovery from wastewater is gaining significance as utilities work toward achieving energy neutrality and sustainability in their wastewater collection and treatment systems. In this dissertation, kinetic energy harvesting mechanism for vortex drop structures found within the municipal waste and storm water conveyance systems is presented. There are thousands of sewer drop structures installed across the U.S. carrying billions of gallons of sewage each year. A custom micro water turbine is developed in this research which could be retrofitted within the existing drop shafts to harvest the excessive kinetic energy available. This dissertation presents the conceptual design and analysis of …


Project Risk Propagation Modeling Of Engineering, Procurement And Construction, Alireza Atin 2016 Wayne State University

Project Risk Propagation Modeling Of Engineering, Procurement And Construction, Alireza Atin

Wayne State University Dissertations

The construction industry is complicated since it involves a variety of stakeholders, challenging environmental issues, huge investments, complex economic and political factors, and other features which may cause an uncertain and unpredictable environment for construction projects. Impacts of risk events can transfer from one phase (source) of a construction project to another phase (target) very quickly and can cause more damage in other phases. Thus, two surveys were conducted to understand the risk propagation phenomena among the engineering, procurement, and construction phases. We conducted two surveys and analyzed data acquired by using sensitive analysis and binary logistic regression modeling. Risk …


Operational And Water Quality Analysis For The City Of Akron's Water Treatment Plant And Distribution System, Chelsea James 2016 the university of akron

Operational And Water Quality Analysis For The City Of Akron's Water Treatment Plant And Distribution System, Chelsea James

Williams Honors College, Honors Research Projects

Chlorination is one of the most common methods of treating pathogens and ensuring microbial water quality in water treatment and distribution. As chlorinated water leaves the source and travels through the water distribution system, the chlorine reacts with both the organic compounds (dissolved organic carbon, DOC) in the source water and the corrosion or biofilm of the pipe walls. The chlorine concentration, or chlorine residuals, at any point in the water distribution system is a good measure of water quality. At the same time, chlorination produces disinfection byproducts as the chlorine also reacts with other naturally-occurring materials in the water. …


Strain Distribution And Crack Detection In Thin Unbonded Concrete Pavement Overlays With Fully Distributed Fiber Optic Sensors, Yi Bao, Genda Chen 2016 Missouri University of Science and Technology

Strain Distribution And Crack Detection In Thin Unbonded Concrete Pavement Overlays With Fully Distributed Fiber Optic Sensors, Yi Bao, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims at evaluating the feasibility of strain measurement and crack detection in thin unbonded concrete pavement overlays with pulse prepump Brillouin optical time domain analysis. Single-mode optical fibers with two-layer and three-layer coatings, respectively, were applied as fully distributed sensors, their performances were compared with analytical predictions. They were successfully protected from damage during concrete casting of three full-scale concrete panels when 5 to 10-cm-thick protective mortar covers had been set for 2 h. Experimental results from three-point loading tests of the panels indicated that the strain distributions measured from the two types of sensors were in good …


Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi 2016 University of Central Florida

Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi

Electronic Theses and Dissertations

Sinkholes are natural geohazard phenomena that cause damage to property and may lead to loss of life. They can also cause added pollution to the aquifer by draining unfiltered water from streams, wetland, and lakes into the aquifer. Sinkholes occur in a very distinctive karst geology where carbonate, limestone, dolomite, or gypsum, are encountered as the bedrock that can naturally be dissolved by groundwater circulating through them. Sinkholes can occur gradually or suddenly with catastrophic impact depending on the geology and hydrology of the area. Predicting the formation and the collapse of a sinkhole based on the current ground investigation …


Dynamic Modeling Approach To Quantify Change Orders Impact On Labor Productivity, Zain Al-Kofahi 2016 University of Central Florida

Dynamic Modeling Approach To Quantify Change Orders Impact On Labor Productivity, Zain Al-Kofahi

Electronic Theses and Dissertations

In construction projects, change orders are commonly faced. These change orders, which are issued by the owner, may cause interruption to the contractor's work, resulting in damages such as loss of labor productivity, delay damages, and cost overruns which may lead to claims. The relationship between change orders and loss of labor productivity is not well understood because of the difficulty in linking the cause of the productivity loss to the change order. So, to receive compensation, the contractor needs to prove with a credible calculation that the productivity loss was a result of the change order issued by the …


Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad 2016 University of Central Florida

Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad

Electronic Theses and Dissertations

The study contributes to safety literature on transportation safety by employing copula based models for count frequency analysis at a macro-level. Most studies in the transportation safety area identify a single count variable (such as vehicular, pedestrian or bicycle crash counts) for a spatial unit and study the impact of exogenous variables. While the traditional count models perform adequately in the presence of a single count variable, it is necessary to modify these approaches to examine multiple dependent variables for each study unit. To that extent, the current research effort contributes to literature by developing two multivariate models based on …


Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad 2016 University of Central Florida

Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad

Electronic Theses and Dissertations

The objective of this study is to analyze the driving behavior at toll plazas by examining multiple scenarios using a driving simulator to study the effect of different options including different path decisions, various signs, arrow markings, traffic conditions, and extending auxiliary lanes before and after the toll plaza on the driving behavior. Also, this study focuses on investigating the effect of drivers' characteristics on the dangerous driving behavior (e.g. speed variation, sudden lane change, drivers' confusion). Safety and efficiency are the fundamental goals that transportation engineering is always seeking for the design of highways. Transportation agencies have a crucial …


An Integrated Hydrodynamic-Marsh Model With Applications In Fluvial, Marine, And Mixed Estuarine Systems, Karim Alizad 2016 University of Central Florida

An Integrated Hydrodynamic-Marsh Model With Applications In Fluvial, Marine, And Mixed Estuarine Systems, Karim Alizad

Electronic Theses and Dissertations

Coastal wetlands experience fluctuating productivity when subjected to various stressors. One of the most impactful stressors is sea level rise (SLR) associated with global warming. Research has shown that under SLR, salt marshes may not have time to establish an equilibrium with sea level and may migrate landward or become open water. Salt marsh systems play an important role in the coastal ecosystem by providing intertidal habitats and food for birds, fish, crabs, mussels, and other animals. They also protect shorelines by dissipating flow and damping wave energy through an increase in drag forces. Due to the serious consequences of …


Getting To Net Zero Energy Buildings: A Holistic Techno-Ecological Modeling Approach, Mehdi Alirezaei 2016 University of Central Florida

Getting To Net Zero Energy Buildings: A Holistic Techno-Ecological Modeling Approach, Mehdi Alirezaei

Electronic Theses and Dissertations

Buildings in the United States are responsible for more than 40% of the primary energy and 70% of electricity usage and greatly in CO2 emission by about 39%, more than any other sector including transportation and industry sectors. This energy consumption is expected to grow mainly due to increasing trends in new buildings construction. Rising energy prices alongside with energy independencies, limited resources, and climate change have made the current situation even worse. An Energy Efficient (EE) building is able to reduce the heating and cooling load significantly compared with a code compliant building. Furthermore, integrating renewable energy sources in …


Circular Rc Columns Partially Confined With Frp, Sahar Y. Ghanem 2016 University of Kentucky

Circular Rc Columns Partially Confined With Frp, Sahar Y. Ghanem

Theses and Dissertations--Civil Engineering

Wrapping reinforced concrete (RC) columns with Fiber Reinforced Polymer (FRP) composites is effective in increasing their capacity. The current state of art concentrates primarily on fully wrapped RC columns and few studies dealt with partially wrapped columns. The majority of the studies did not account for the influence of the existing steel reinforcement on the column’s behavior. Other studies estimated the total confinement pressure as the sum of the confinement pressure due to the external FRP jacketing and due to the internal transverse steel reinforcement. Few models dealt with the coupled effect of the confinement from steel and partial FRP …


3d Infrastructure Condition Assessment For Rail Highway Applications, Teng Wang 2016 University of Kentucky

3d Infrastructure Condition Assessment For Rail Highway Applications, Teng Wang

Theses and Dissertations--Civil Engineering

Highway roughness is a concern for both the motoring public and highway authorities. Roughness may even increase the risk of crashes. Rail-highway grade crossings are particularly problematic. Roughness may be due to deterioration or simply due to the way the crossing was built to accommodate grade change, local utilities, or rail elevation. With over 216,000 crossings in the US, maintenance is a vast undertaking. While methods are available to quantify highway roughness, no method exists to quantitatively assess the condition of rail crossings. Conventional inspection relies on a labor-intensive process of qualitative judgment. A quantifiable, objective and extensible procedure for …


Underwater Explosion Energy Dissipation Near Waterborne Infrastructure, Paul R. Smith 2016 University of Kentucky

Underwater Explosion Energy Dissipation Near Waterborne Infrastructure, Paul R. Smith

Theses and Dissertations--Civil Engineering

Underwater explosions pose a significant threat to waterborne infrastructure though destructive pressure waves that can travel significant distances through the water. However, the use of bubble screens can attenuate the peak pressure and energy flux created by explosions to safe levels. This study investigates the prediction of pressure wave characteristics based on accumulated data, the damage potential of underwater explosions based on applied loads and effective material strength, and the bubble screen parameters required to prevent damage. The results were compiled to form a procedure for the design and implementation of a bubble screen the protection of waterborne infrastructure.


Transient-Based Risk Analysis Of Water Distribution Systems, Steven Hoagland 2016 University of Kentucky

Transient-Based Risk Analysis Of Water Distribution Systems, Steven Hoagland

Theses and Dissertations--Civil Engineering

Water distribution system utilities must be able to maintain a system’s assets (i.e., pumps, tanks, water mains, etc.) in good working condition in order to provide adequate water quantity and quality to its customers. Various asset management approaches are employed by utilities in order to make optimal decisions regarding the renewal of system components. Part of a good asset management approach is performing a comprehensive risk analysis which consists of considering all potential ways in which the system may fail, the likelihood failure of for each scenario, and the consequences of said failure. This study investigates a water distribution system’s …


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