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2016

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Articles 1921 - 1950 of 2180

Full-Text Articles in Civil and Environmental Engineering

Reuse Of Aqueous Waste Streams For Transportation-Related Applications, Gregory L. Hansen Jan 2016

Reuse Of Aqueous Waste Streams For Transportation-Related Applications, Gregory L. Hansen

Electronic Theses and Dissertations

Aqueous waste streams produced from commercial, industrial, and municipal processes may be potentially reused for transportation applications. The objectives of this project were to identify potential transportation-related applications for aqueous waste streams available in South Dakota, develop guidance for the beneficial reuse of aqueous waste streams, and evaluate the reuse of MIEX® brine generated by the Watertown Municipal Water Treatment Plant (WMWTP). This study identified many aqueous wastes from municipal water and wastewater treatment facilities, industrial and agricultural processes in South Dakota that can be potentially used for ice and dust control. Beneficial reuse of these waste streams requires a …


Pumping Of Fresh Concrete: Insights And Challenges, Geert De Schutter, Dimitri Feys Jan 2016

Pumping Of Fresh Concrete: Insights And Challenges, Geert De Schutter, Dimitri Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Pumping of Fresh Concrete is of Utmost Importance for Concrete Practice. Required Pumping Pressures Are Typically Estimated based on Design Charts. However, with the Increased Use of Chemical Admixtures and the Development of More Flowable Concrete Mixtures, the Accuracy of Traditional Design Charts is Questioned. in Recent Years, Significant Progress Has Been Obtained in Understanding the Flow of the Material in the Pumping Pipe, Including the Behavior of the Lubrication Layer Near the Pipe Surface. in Comparison with Traditional Design Charts, This Results in More Reliable Pressure Predictions When Considering Very Fluid Concrete Types Like Self-Consolidating Concrete. Some Remaining Challenges …


Specification Development For Cold In-Situ Recycling Of Asphalt, Amir Tabakovic, Ciaran Mcnally, Eanna Fallon Jan 2016

Specification Development For Cold In-Situ Recycling Of Asphalt, Amir Tabakovic, Ciaran Mcnally, Eanna Fallon

Research and Innovation - Articles

In-situ cold recycling provides a valuable means to reduce the environmental impact of road construction. The reduced energy requirements relative to traditional hot mix recycling can lead to significant reductions in cost and associated CO2 emissions. Worldwide, in-situ cold recycling has been found to be particularly useful in the rehabilitation of rural roads where site locations are far from asphalt plants. However, practical issues remain due to the evolving nature of cold bituminous materials. Unlike hot-mix asphalts which gain strength quickly as they cool, cold-mix bituminous materials gain strength slowly over time. This is particularly an issue in countries …


The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud Jan 2016

The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud

Open Access Theses & Dissertations

Using a suite of modeling techniques and instrumentation we study the atmospheric pollutants in the PdN Region. The first objective of this work was to measure hemi-spherically integrated, spectrally resolved solar photon flux (actinic flux) between the wavelengths 300 and 700 nm, and use the measured actinic flux to improve air quality simulations. Actinic flux was measured in the PdN region in order to calculate photolysis rate coefficients for different pollutants. The improved photolysis rate coefficients were then integrated into a photochemical air quality model (CAMx) in order to improve air quality forecasting. We present the simulations performed for a …


Resolving The Policy Paradox: The Case Of Biofuel Production In Ireland, Alan Gilmer, Mark J. Mcgarrity, Vivienne Byers Jan 2016

Resolving The Policy Paradox: The Case Of Biofuel Production In Ireland, Alan Gilmer, Mark J. Mcgarrity, Vivienne Byers

Articles

Purpose – The purpose of this paper is to determine the status of policy design and policy implementation in the biofuel sector in Ireland. The focus of the work addresses the overarching operational context of the biofuel sector in Ireland and the role of different actors in shaping and resolving inconsistencies in policy outlook and practice. Design/methodology/approach – This study used a qualitative research approach involving a series of semi-structured interviews with members of the relevant sub-groups concerned. This study sought to address two questions – whether current or proposed policy is likely to affect consumption of indigenous biofuel feedstocks …


An Overview Of The Development Of Cement-Based Batteries For The Cathodic Protection Of Embedded Steel In Concrete, Aimee Byrne, Niall Holmes, Brian Norton Jan 2016

An Overview Of The Development Of Cement-Based Batteries For The Cathodic Protection Of Embedded Steel In Concrete, Aimee Byrne, Niall Holmes, Brian Norton

Conference papers

This paper presents an overview of the cement-based batteries developed in DIT for use in the cathodic protection of embedded steel in reinforced concrete undergoing chloride-induced corrosion. Cathodic protection delivers an external current (approximately 20mA per m2 of embedded steel) which effectively polarises the internal current generated during corrosion. The batteries developed in DIT comprise of a cement-based electrolyte containing different additives including sand, aggregate, salts, carbon black and plasticiser with protruding anode and cathode metal plates. These batteries produced an initial electrical output of 1.5V and 23mA through a 10 resistor as measured using data acquisition units and a …


Using Photovoltaics To Power Electrochemical Chloride Extraction From Concrete, Sean Bond, Lynette O'Callaghan, Niall Holmes Dr., Brian Norton Jan 2016

Using Photovoltaics To Power Electrochemical Chloride Extraction From Concrete, Sean Bond, Lynette O'Callaghan, Niall Holmes Dr., Brian Norton

Conference papers

Corrosion of embedded steel in reinforced concrete (RC) is a world-wide problem, that reduces structural performance and lifespan. Chloride attack may be a result of seawater, de-icing salts or contaminated admixtures, brought on by ingress of chlorides into the concrete. Electrochemical Chloride Extraction (ECE) is a non-destructive treatment for contaminated RC structures, that due to uncertainty of treatment times and applied current densities, is only 50% effective. It is often diesel powered has an environmental impact and often very costly due to the long treatment times. To improve the efficiency of ECE the influences of concrete resistance, cement type and …


Developing Graduate Attributes To Meet The Grand Challenges: What Pedagogical Factors Influence The Development Of Graduate Attributes And Does Engineering Education Ensure Graduates Can Address The Global Grand Challenges?, Una Beagon, Brian Bowe Jan 2016

Developing Graduate Attributes To Meet The Grand Challenges: What Pedagogical Factors Influence The Development Of Graduate Attributes And Does Engineering Education Ensure Graduates Can Address The Global Grand Challenges?, Una Beagon, Brian Bowe

Conference papers

My interest in preparing graduates for a successful career in industry stems from personal experience of employing graduates as civil and structural engineers in an engineering consultancy role. The range of skills, abilities and values of each graduate was varied, and it became apparent that academic achievement, whilst important was not the defining skill for achieving early responsibility or promotion within the company. More often, the graduate who was able to communicate well and self-direct his/her work was given more responsibility and opportunity. Many graduates would define early promotion, advanced responsibility and the associated increase in salary as the beginnings …


A Literature Review Of The Evolution Of British Prefabricated Low-Rise Housing, Daniel O'Neill, Samantha Organ Jan 2016

A Literature Review Of The Evolution Of British Prefabricated Low-Rise Housing, Daniel O'Neill, Samantha Organ

Articles

Purpose – The purpose of this paper is to explore academic papers and reports and present a chronology of the evolution of British low-rise prefabricated housing. The paper provides chronological information for construction and surveying researchers undertaking research in associated areas.

Design/methodology/approach – This is a qualitative literature review, providing an exploration and analysis of academic papers and reports on low-rise prefabricated housing.

Findings – A substantial literature was discovered. However, there are gaps in the available literature. The history of British construction technology is a rich research area but is under-researched. Prefabricated housing has a long history dating back …


Main Contractor Selection On Construction Projects When Adapting An Integrated Project Delivery Procurement Strategy Within An Irish Context., Fiacra Mcdonnell Jan 2016

Main Contractor Selection On Construction Projects When Adapting An Integrated Project Delivery Procurement Strategy Within An Irish Context., Fiacra Mcdonnell

Other Resources

The Irish construction industry has experienced turbulent years over the last decade from an economic viewpoint. The industry has tended to be conservative in nature and slow to embrace change. However international influences have exposed Irish construction professionals to new more efficient systems and technologies, which although slow to take hold have started to gain traction within certain sectors of the industry. This study has focussed on the innovative procurement route known as Integrated Project Delivery (IPD), and its facilitator; Building Information Modelling (BIM). The overall aim of this study was to investigate whether Integrated Project Delivery was a viable …


Experimental Rapid Renewal Project (Bridge Construction), Bobby W. Meade, Sudhir Palle, Theodore Hopwood Ii Jan 2016

Experimental Rapid Renewal Project (Bridge Construction), Bobby W. Meade, Sudhir Palle, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The objectives of this study were to develop specifications and contract language and to monitor the implementation them to effectively use rapid reconstruction and extended service life concepts in new bridge construction. Through the use of A + B bidding, a duplex protective coating system using Hot Dipped Galvanizing (HDG) and paint, and preservation techniques such as concrete sealers and stains the Kentucky Transportation Cabinet attained those goals.


Pore Pressure Measurement Instrumentation Response To Blasting, Kylie M. Larson-Robl Jan 2016

Pore Pressure Measurement Instrumentation Response To Blasting, Kylie M. Larson-Robl

Theses and Dissertations--Mining Engineering

Coal mine impoundment failures have been well documented to occur due to an increase in excess pore pressure from sustained monotonic loads. Very few failures have ever occurred from dynamic loading events, such as earthquakes, and research has been done regarding the stability of these impoundment structures under such natural seismic loading events. To date no failures or damage have been reported from dynamic loading events caused by near-by production blasting, however little research has been done considering these conditions. Taking into account that current environmental restrictions oblige to increase the capacity of coal impoundments, thus increasing the hazard of …


An Intermodal Network Model Of Coal Distribution In The United States And Its Economic Implications For The Inland Waterway System, Benjamin L. Blandford, Ted H. Grossardt, Michael Shouse, John Ripy Jan 2016

An Intermodal Network Model Of Coal Distribution In The United States And Its Economic Implications For The Inland Waterway System, Benjamin L. Blandford, Ted H. Grossardt, Michael Shouse, John Ripy

Kentucky Transportation Center Research Report

This paper describes a GIS-based intermodal network model for the shipment of coal in the United States. The purpose of this research was to investigate the role played by railways, waterways, and highways in the movement of coal from its source area to point of use, and to highlight the implications these movements have for the U.S. economy. The project team modeled coal movements across the U.S. intermodal transportation network using the Energy Information Administration’s 2010 data, which provided detailed origin, destination, primary mode, and volume information for coal shipments. The model identifies the optimum routes for coal shipments based …


Kentucky Traffic Collision Facts 2015, Kentucky Transportation Center, Kentucky State Police Jan 2016

Kentucky Traffic Collision Facts 2015, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC COLLISION FACTS report for 2015 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 …


Modeling Long-Term Deformations Of Unbound Pavement Materials Using The Miniaturized Pressuremeter Creep Data, A. M. Shaban, P. J. Consentino Jan 2016

Modeling Long-Term Deformations Of Unbound Pavement Materials Using The Miniaturized Pressuremeter Creep Data, A. M. Shaban, P. J. Consentino

Mechanical and Civil Engineering Faculty Publications

This research was undertaken to study the predictive capability of the pressuremeter test for characterizing in situ creep behavior of unbound pavement layers. Although the creep potential of granular pavement materials is less pronounced than fine-grained soils, consideration of actual creep deformations in the pavement evaluation process will improve long-term pavement performance. In this investigation, the long-term deformations determined from laboratory one-dimensional creep tests were compared with those investigated by field pressuremeter tests. The pressuremeter test consisted of inflating a cylindrical probe incrementally up to a given stress level, and then maintaining the pressure constant for a 5-min single stage. …


Object Detection For Agricultural And Construction Environments Using An Ultrasonic Sensor, Joseph S. Dvorak, Marvin L. Stone, Kelvin P. Self Jan 2016

Object Detection For Agricultural And Construction Environments Using An Ultrasonic Sensor, Joseph S. Dvorak, Marvin L. Stone, Kelvin P. Self

Biosystems and Agricultural Engineering Faculty Publications

This study tested an ultrasonic sensor‘s ability to detect several objects commonly encountered in outdoor agricultural or construction environments: a water jug, a sheet of oriented strand board (OSB), a metal fence post, a human model, a wooden fence post, a Dracaena plant, a juniper plant, and a dog model. Tests were performed with each target object at distances from 0.01 to 3 m. Five tests were performed with each object at each location, and the sensor‘s ability to detect the object during each test was categorized as "undetected," "intermittent," "incorrect distance," "good." Rigid objects that presented a larger surface …


Reactivity Of Hydroxyl Radical: Mechanistic Insight Into The Reactivity With Dissolved Organic Matter, Mallika Khare Jan 2016

Reactivity Of Hydroxyl Radical: Mechanistic Insight Into The Reactivity With Dissolved Organic Matter, Mallika Khare

Dissertations, Master's Theses and Master's Reports

Advanced Oxidation Processes (AOPs) that produce highly reactive hydroxyl radicals (HO•) are attractive and promising water and wastewater treatment technologies because HO• can destroy a variety of organic compounds. However, background dissolved organic matter (DOM) significantly reduces the performance of AOPs by scavenging HO•. The conventional experimental approach to identifying ‘average’ reactivity limits our mechanistic understanding of the reaction of HO• with complex mixture of surrogate DOM. This is the first study to use quantum mechanical methods to understand the elementary reactions of HO• with a model monomer of DOM. “Temple Northeastern Birmingham model” (TNB). The theoretically calculated aqueous-phase free …


Evaluating The Anaerobic Codigestion Potential Of Stillage And Dairy Manure In A Tubular Digester, Brad J. Weiss Jan 2016

Evaluating The Anaerobic Codigestion Potential Of Stillage And Dairy Manure In A Tubular Digester, Brad J. Weiss

Dissertations, Master's Theses and Master's Reports

Evaluations of the anaerobic treatment of sugarcane stillage and dairy manure in a low cost tubular digester were performed in small scale batch experiments and using mathematical simulations. A local sensitivity analysis of the model was performed, and key input parameters were adjusted until the predicted COD removal was consistent with data obtained using two full-scale digesters. Simulations were performed to evaluate COD removal and biogas production for nine different mixtures of stillage and manure at four different temperatures ranging from 15˚C to 30˚C. Digestion of stillage alone was not effective, but when codigested with 20% or more manure, COD …


Use Of Lidar In The Design Of Grassed Waterways: Case Study In Agricultural Management In Oklahoma, Annette Sparks Jan 2016

Use Of Lidar In The Design Of Grassed Waterways: Case Study In Agricultural Management In Oklahoma, Annette Sparks

Dissertations, Master's Theses and Master's Reports

Before the advent of Light Detection and Ranging (LiDAR) technology, farm-level infrastructure for sustainable agriculture was designed using topographic maps. LiDAR is a remote sensing method whereby reflected laser pulses are measured to generate high-resolution 3D images of the terrain. This report compares these two methods in the design of grassed waterways for flood drainage and evaluates how the quantitative difference between the two methods can affect the overall hydrologic design. The benefits of LiDAR are expected to be higher accuracy and precision in design, as well as greater reproducibility or consistency, regardless of the designer. To carry out this …


2016 Nebraska Groundwater Quality Monitoring Report Jan 2016

2016 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …


Validation Of Integrated Coast-Ocean Model Cche2d-Coast And Development Of Wind Model, Afshin Gazerzadeh Jan 2016

Validation Of Integrated Coast-Ocean Model Cche2d-Coast And Development Of Wind Model, Afshin Gazerzadeh

Electronic Theses and Dissertations

The eastern and southern coastlines of the United States are two of the most cyclone-prone areas of the world. The effects of tropical cyclones vary mainly depending on wind intensity and geological features of the coast that it is crossing. Higher winds potentially generate higher storm surges and consequently larger floods occur along the coastlines. Therefore, it is critical to accurately predict winds, storm surge, and waves associated with a hurricane. In the present study, an integrated coastal and ocean process model, CCHE2D-Coast, is validated by assessing the model’s capabilities in simulating coast-ocean circulations driven by the astronomical tides on …


Flood Disaster Resilient Bridge Structures For Sustainable Bridge Management Systems, Alper Durmus Jan 2016

Flood Disaster Resilient Bridge Structures For Sustainable Bridge Management Systems, Alper Durmus

Electronic Theses and Dissertations

Extreme weather events are occurring at an increasing ferocity and frequency. Floods are the most comand damaging natural disaster. More than 4,400 occurrences of flood disasters have been reported globally between 1900 and 2016. As a result, around seven million people were killed and millions more were displaced. Climate impacts are expected to intensify weather related flooding events, and sea level rise expected worldwide will increase the risk of coastal disasters. Transportation infrastructure, vital to the economy and society of every country, is especially prone to the inland and coastal floods. Bridge structures are under the constant threat of these …


Bridge Rating Based On In-Situ Weigh-In-Motion And Health Monitoring Data, Dana Feng Jan 2016

Bridge Rating Based On In-Situ Weigh-In-Motion And Health Monitoring Data, Dana Feng

LSU Doctoral Dissertations

Parallel to the bridge design methodology changes from the Allowable Stress Design to the Load Factor Design, and then to the reliability based Load and Resistance Factor Design (LRFD), bridge load rating method has also been evolving. Applying the reliability theory to the bridge load rating is more complex than applying to the LRFD since any conservatism can have a significant effect on the assessment of bridge capacity, particularly in load posting and bridge replacement. Although the current Load and Resistant Factor Rating (LRFR) method applying the concept of reliability analyses, it uses very limited site-specific data due to practical …


Performance Evaluation Of Instrumented Geosynthetics Reinforced Paved Test Sections Built Over Weak Subgrade Using Accelerated Load Testing, Shadi Hanandeh Jan 2016

Performance Evaluation Of Instrumented Geosynthetics Reinforced Paved Test Sections Built Over Weak Subgrade Using Accelerated Load Testing, Shadi Hanandeh

LSU Doctoral Dissertations

Weak soil is a common problem in road construction. Whether it is a temporary access road or a permanent road built over a weak subgrade, a large deformation of the subgrade can lead to deterioration of the paved or unpaved surface. Geosynthetics offer a potentially economical solution for stabilizing roads built over weak soil. Three sets of testing programs were be conducted in this study.The first testing program includes conducting accelerated load testing of full-scale geosynthetic reinforced test lanes using rolling wheel load facility; the second program included conducting laboratory cyclic plate loading test on geosynthetic reinforced test sections constructed …


Coastal Flood Risk In A Changing Climate Along The Northern Gulf Of Mexico, Matthew Vernon Bilskie Jan 2016

Coastal Flood Risk In A Changing Climate Along The Northern Gulf Of Mexico, Matthew Vernon Bilskie

LSU Doctoral Dissertations

Coastal regions around the world are experiencing increased vulnerability from natural and manmade disasters. It is anticipated that coastal flood risk will increase due to the effects of climate change, and sea level rise (SLR) in particular. A dynamic, physics-based, framework to compute coastal flood inundation maps under various climate change scenarios was developed. The novel modeling system includes not only SLR, but considers future projections of shoreline evolution and primary dune morphology, upland migration of intertidal marsh, and land use land cover change. A present day hurricane storm surge model was generated for the Mississippi, Alabama, and Florida panhandle …


Strengthening Shear Deficient Thin-Walled Steel Beams By Bonding Pultruded Gfrp Sections, Tuna Ulger Jan 2016

Strengthening Shear Deficient Thin-Walled Steel Beams By Bonding Pultruded Gfrp Sections, Tuna Ulger

LSU Doctoral Dissertations

Rehabilitation and retrofitting methods offer economical and feasible alternatives for upgrading aged and deficient structures. Structural strengthening using Fiber Reinforced Polymer (FRP) composites have been widely investigated by researchers and used in field applications. The main advantage of FRP composites is the superior mechanical properties they offer over traditional structural materials. One novel alternative of these retrofitting methods was developed at Louisiana State University and called “Strengthening-by-Stiffening” (SBS). In SBS, the external strengthening of shear deficient thin-walled steel structures is achieved by bonding pultruded FRP sections to buckling prone web panels. Contrary to the commonly used uniaxial tension resistance of …


Characterization Of Human-Induced Vibrations, Benjamin Thomas Davis Jan 2016

Characterization Of Human-Induced Vibrations, Benjamin Thomas Davis

Theses and Dissertations

In the US alone, 20% of citizens will be over the age of 65 by the year 2030, and the largest challenge facing this growing demographic is not a new disease but a simple motion - the fall. These events are the premier cause of fatal and nonfatal injuries. In fact, a fall is so common that every 17 seconds an older adult is treated for fall-related injuries, and every 30 minutes, an older adult dies from fall complications. Research has shown a positive outcome of a fall event is largely dependent on the immediate response (<30 minutes) and rescue of the person.

This work explores …


Deposits Emplaced In Upper Regime, Ricardo Rafael Hernández Moreira Jan 2016

Deposits Emplaced In Upper Regime, Ricardo Rafael Hernández Moreira

Theses and Dissertations

Relatively common to the submarine setting are depositional sequences that begin with a lower erosional boundary, followed in ascending order by a either a graded or an inherently massive basal unit, a relatively coarse parallel laminated unit, a cross laminated unit, a relatively fine parallel laminated unit, and a capping layer of massive mud. These sequences are present in turbidity current, coastal storm and tsunami deposits, and their study is the key to understanding the physical processes governing sediment transport, erosion and deposition in submarine settings, to the reconstruction of global paleoclimate and paleoflow, to the exploration of hydrocarbon reservoirs …


Assessment, Prevention And Remediation Of Corrosion In Weathering Steel Transmission Line Poles, Matthew Bruce Barragan Jan 2016

Assessment, Prevention And Remediation Of Corrosion In Weathering Steel Transmission Line Poles, Matthew Bruce Barragan

Theses and Dissertations

Electric utilities routinely use weathering steel (WS) in transmission line structures, capitalizing on corrosion resistance and associated cost savings. The formation of a protective iron-oxide patina on uncoated above-ground WS surfaces depends on the operating environment and exposure conditions. In fact, exposure to common aggressive environments, such as those found in sulfate-contaminated industrial areas and chloride-laden coastal areas, may dramatically hinder the corrosion resistance of WS transmission line structures.

To assess the corrosion behavior of WS transmission line poles, field inspections were conducted at five test sites comprising diverse operating environments and pole designs. These sites included three locations in …


Use Of Biochar-Ultrafiltration Membrane Processes For Removal Of Humic Acid, Vaibhavi Shankar Jan 2016

Use Of Biochar-Ultrafiltration Membrane Processes For Removal Of Humic Acid, Vaibhavi Shankar

Theses and Dissertations

The performance of an ultrafiltration (UF)-biochar process was evaluated in comparison with a UF membrane process for the removal of humic acid (HA). Bench-scale UF experiments were conducted to study the rejection and flux trends under various hydrodynamic, pH, conductivity, and pressure conditions. The resistance-in-series model was used to evaluate the processes and it showed that unlike stirred conditions, where low fouling resistance was observed, comparable trends were obtained for UF-biochar and UF alone for unstirred conditions. Thus, the processes were further evaluated under unstirred conditions. Additionally, total fouling resistance was decreased in the presence of biochar, indicating that HA …