Engineering Commons^™

Studies Of Hydrophobic Organic Pollutant Interactions With Cyclodextrin: Implication For Groundwater Remediation, Heng Gao

LSU Doctoral Dissertations

Henry’s Law constants of several common, subsurface hydrophobic organic pollutants (HOPs) including trichloroethylene (TCE), perchloroethylene (PCE) and benzene, toluene, ethylbenzene and o-xylene (BTEX), were measured over a range of temperatures (35, 45, 55 and 65°C) and cyclodextrin (CD) concentrations (0, 10, 20, 50 and 100 g L-1). In aqueous CD solutions, Henry’s constant values decrease by a power law relationship with increasing CD concentration due to an apparent solubility enhancement caused by HOP partitioning to the hydrophobic cavity of CD molecules. The temperature dependence of air-water partitioning under the influence of CD was well described by the van’t Hoff equation …

Optimum Design Of Cable-Stayed Bridges, Mahmoud M. Hassan

Digitized Theses

Owing to their excellent structural characteristics, aesthetic appearance, low maintenance cost, and efficient use of structural materials, cable-stayed bridges have gained much popularity in recent decades. Stay cables of a cable stayed bridge are post-tensioned to counteract the effect of the bridge dead load. The solution for an optimum distribution of post-tensioning cable forces is considered one of the most important and difficult tasks in the design of cable-stayed bridges. A novel approach that utilizes the finite element method, B-spline curves, and real coded genetic algorithm to determine the global optimum post-tensioning cable forces is developed. The effect of geometric …

Influence Of Unstable Soil Movement On Pile-Founded Concrete Floodwalls And A Resulting Design Methodology, Richard James Varuso

LSU Doctoral Dissertations

Efforts are underway in the New Orleans area to raise the elevations of its levee system to combat the effects of hurricane storm surge. When complete, the majority of the system will be comprised of a combination of levees, sheet pile I-Walls, floodgates, and pile-supported concrete floodwalls, commonly referred to as T-Walls. Given the magnitude of the hydrostatic forces associated with storm surge, global instability is failure mechanism that must be considered in the design of T-Walls. In the past, it was assumed that these forces would be resisted by the T-Wall’s sheet pile cut-off wall. Recent literature review and …

Transit-Based Emergency Evacuation Modeling With Microscopic Simulation, Hana H. Naghawi

LSU Doctoral Dissertations

Several recent mass evacuations, including those in advance of Hurricane Katrina in New Orleans and Hurricane Rita in Houston, have demonstrated the effects of limited planning for carless populations. The lack of planning left a significant portion of the mobility-limited population of both these cities unable to flee in advance of the storms. Since 2005 however, both of these cities (as well as others across the United States) have developed transit assisted mass evacuation plans at various levels of detail. Since these plans are relatively recent and do not have a history of experience on which to base their performance, …

Quantitative Comparison And Modeling Of Urban Storm Water Mass Loadings In The City Of Lincoln, Nebraska, Patrick R. Hartman

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

QUANTITATIVE ANALYSIS AND MODELING OF URBAN STORM WATER MASS LOADINGS IN THE CITY OF LINCOLN, NEBRASKA

Patrick Ryan Hartman, M. S. University of Nebraska, 2010

Advisors: Bruce I. Dvorak, David M Admiraal

The main goal of this study is to monitor, and then compare results related to the water quality and mass loadings of several constituents at two sites in Lincoln, NE. Differences in water quality were assessed using matched-pair t-tests. Mass loadings were examined using cumulative mass plots, and a predictive model for total suspended solids (TSS) was developed at both sites using real-time data obtained from a USGS …

Chemical Compatibility Of Soil-Bentonite Cutoff Wall Backfills Containing Modified Bentonites, Matthew D. Mckeehan

Master’s Theses

This study examined the chemical compatibility of several model soil-bentonite(SB) backfills with an inorganic salt solution (CaCl2). First, bentonite-water slurry was created using a natural sodium-bentonite, as well as two modified bentonites –multiswellable bentonite (MSB) and a “salt-resistant” bentonite (SW101). Once slurries that met typical construction specifications had been created using the various bentonites,the model SB backfills were prepared for each type of bentonite. These backfills werealso designed to meet conventional construction and design requirements. The SB backfills were then subjected to permeation with tap water and/or CaCl2 solutions of various concentrations in order to evaluate the compatibility of the …

Investigating The Effects Of Various Crowd Characteristics On The Dynamic Properties Of An Occupied Structure, Robert Joseph Firman Iii

Honors Theses

One of the challenges for structural engineers during design is considering how the structure will respond to crowd-induced dynamic loading. It has been shown that human occupants of a structure do not simply add mass to the system when considering the overall dynamic response of the system, but interact with it and may induce changes of the dynamic properties from those of the empty structure. This study presents an investigation into the human-structure interaction based on several crowd characteristics and their effect on the dynamic properties of an empty structure. The dynamic properties including frequency, damping, and mode shapes were …

Behavior Of Externally Bonded Fiber Reinforced Polymer Systems For Strengthening Concrete Girders In Shear, Michael Shawn Murphy

Doctoral Dissertations

"Deficiencies in shear resistance are a primary concern in concrete members due to the sudden and unpredictable nature of shear failures. Shear deficiencies in concrete structures can arise due to improper design, long-term deterioration, man-made damages, increases in loads, or as a result of over strengthening in flexure. A number of shear strengthening techniques offer a cost effective means for restoring or enhancing the shear capacity of a concrete member. The use of externally bonded fiber reinforced polymers (FRP) is one such technique that has gained recent recognition for its high strength-to-weight ratio and simplicity of application. The development of …

Organic Particulate Matter Formation At Varying Relative Humidity Using Surrogate Secondary And Primary Organic Compounds With Activity Corrections In The Condensed Phase Obtained Using A Method Based On The Wilson Equation, James F. Pankow, E. I. Chang

Civil and Environmental Engineering Faculty Publications and Presentations

Secondary organic aerosol (SOA) formation in the atmosphere is currently often modeled using a multiple lumped "two-product" (N · 2p) approach. The N · 2p approach neglects: 1) variation of activity coefficient (i) values and mean molecular weight MW in the particulate matter (PM) phase; 2) water uptake into the PM; and 3) the possibility of phase separation in the PM. This study considers these effects by adopting an (N ·2p)pMW, approach (is a phase index). Specific chemical structures are assigned to 25 lumped SOA compounds and to 15 representative primary organic aerosol (POA) compounds to allow calculation of i …

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Department of Biological Systems Engineering: Papers and Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, …

Nebraska Water And Energy Flux Measurement, Modeling, And Research Network (Nebflux), Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

Surface energy and water vapor fluxes play a critical role in understanding the response of agro‐ecosystems to changes in environmental and atmospheric parameters. These fluxes play a crucial role in exploring the dynamics of water and energy use efficiencies of these systems. Quantification of the fluxes is also necessary for assessing the impact of land use and management changes on water balances. Accomplishing these goals requires measurement of water vapor and energy exchanges between various vegetation surfaces and microclimates for long‐enough periods to understand the behavior and dynamics involved with the flux transfer so that robust models can be developed …

Opto-Electrophoretic Detection Of Bio-Molecules Using Conducting Chalcogenide Glass Sensors, Zhiyong Yang, Megan K. Fah, Kelly A. Reynolds, Jonathan D. Sexton, Mark R. Riley, Marie-Laure Anne, Bruno Bureau, Pierre Lucas

Department of Biological Systems Engineering: Papers and Publications

Novel telluride glasses with high electrical conductivity, wide infrared transparency and good resistance to crystallization are used to design an opto-electrophoretic sensor for detection and identification of hazardous microorganisms. The sensor is based on an attenuated total reflectance element made of Ge-As-Te glass that serves as both an optical sensing zone and an electrode for driving the migration of bio-molecules within the evanescent wave of the sensor. An electric field is applied between the optical element and a counter electrode in order to induce the migration of bio-molecules carrying surface charges. The effect of concentration and applied voltage is tested …

Hydrodynamic Modeling Of San Elijo Lagoon, California, Mary Elizabeth Nee Friedmann Bourgoyne

LSU Master's Theses

Decisions on where to concentrate management efforts need to be guided by an ability to accurately simulate and predict physical and ecological changes. Many restoration projects experience difficulties due to a lack of understanding of the ecological response and evolution of wetland systems (Goodwin et al., 2001). There are several approaches that can be taken in analyzing a system. The appropriate selection should be based on the available data, the spatial scale of the wetland, and the physical processes governing the system (Goodwin and Kamman, 2001). Predictive tools are essential for good long-term management (Goodwin et al., 2001). The objective …

Estimated Impact Of Left Lane Truck Restriction On Louisiana Highway Pavement Using Mepdg, Mini Radhakrishnan

LSU Master's Theses

Truck lane restriction strategies (TLRS) are strategies used to manage truck traffic on highways by prohibiting trucks from using certain lanes in order to minimize interaction between trucks and other vehicles and currently it is under consideration for implementation in Louisiana’s multi-lane highways. One of the serious impacts of a truck lane restriction on highways is accelerated pavement damage on unrestricted lanes due to the increased truck traffic on them. The purpose of this study is to estimate the increased pavement damage on the right lane in terms of various distress caused by imposing left lane truck restriction on trucks …

Reclamation Of Salt From Brine Springs, Tejaswini Anand

Open Access Theses & Dissertations

Sodium-chloride brine underlies the shallow subsurface and discharges in springs and streams at numerous locations in Kent and Stonewall Counties in Central Texas. These discharges eventually flow into the Salt Fork of the Brazos River, lowering the quality of this important surface water resource. One potentially cost effective solution for the problem of excess salt loading to the Brazos River by brine spring discharge is to intercept brine groundwater discharges and either treat or evaporate the water. We have examined the energetic of desalinating and evaporating the water from the brine to produce marketable salt products and distilled water. Our …

Low Impact Development (Lid) Structures For Groundwater Management And Watershed Protection In The Amrc10 Watershed, El Paso Texas, Ricardo Sabino Marmolejo

Open Access Theses & Dissertations

The AMRC10 watershed was modeled in HEC-HMS and in Green Values. Theoretical storm water conveyance and capture models were tested in these programs along with several Low environmental Impact Development features to determine their applicability and performance at this site. Lots should all be designed with all roof downspouts draining into raingardens, at least half of all lawns should be natural landscaping using local vegetation, porous pavement should be used for all driveways, sidewalks and non-street pavement and drainage to the stormwater conveyance structures should make use of drainage swales instead of storm water pipes. To manage runoff three detention …

The Effectiveness Of The Natural Resource Conservation Service (Nrcs) And Huff Rainfall Distribution Methods For Use In Detention Basin Design, Todd Wayne Dablemont

Masters Theses

"This thesis focuses on the effectiveness of the NRCS and Huff rainfall distribution methods for use in detention basin design. This study required the use of HEC-HMS, hydrologic modeling software, in order to analyze the distribution methods. Three separate detention basins and their watersheds were modeled for this study. The watersheds were analyzed for both undeveloped and developed conditions. The parameters analyzed include detention basin inflow, detention basin outflow, watershed peak discharge, and detention basin storage capacity. The determination of detention basin effectiveness was based upon these parameters. The NRCS distribution method is widely used; however, many who use it …

Field Investigation Of Spalling In Bridge Decks With Partial-Depth Precast Concrete Panel Systems Using Non-Destructive Testing, Kandi Rebecca Wieberg

Masters Theses

"This study involved the investigation of the causes of spalling observed in several partial-depth precast prestressed bridge decks in the state of Missouri. Recently it has been observed that several bridges in Missouri with this type of construction have experienced spalling of concrete at the edges of the panels revealing an extreme condition of corrosion in the prestressing tendons, some to the point of rupture. Ground penetrating radar (GPR), which has been shown to be successful in bridge deck evaluation, was used to determine the relative condition of the prestressing tendons as well as the relative condition of the concrete …

The Placement Of Remediation Amendments Into Contaminated Sediments Via Waterjet Technologies, Gavin Hunter Ray Risley

Masters Theses

"The use of amendments to perform in situ remediation of contaminated sediments is a technique that is relatively mature. The need exists to develop a method of amendment delivery that will efficiently place the amendments into the contaminated zone at depth with minimal impacts to the benthic communities and contaminant resuspension. Waterjets have been used for hundreds of years as an excavation, cutting, and cleaning tool, but they can also be used to inject remediation amendments into contaminated sediments if setup properly. In order to test this concept, a waterjet amendment injection system and nozzle have been developed and tested. …

Analysis Of Nationwide Intercity Travel Demand On The Us Transportation Network, Tao Li

Masters Theses

"In this thesis, three issues about the intercity travel demand on the US transportation network are addressed. The final one is the estimation of the domestic passengers' delay cost. A scheme is designed by assuming that costs incurred by flight delays relative to the original flight schedules are imposed at passengers' final destination airports. It is applied to estimate the total domestic delay cost of year 2007 and reasonable results arc obtained. The second one is the air travel demand estimation. Two route-based optimization models are proposed to estimate the travel demand based on available data. It is shown that …

Bayesian Approaches On Observational Before-After Highway Safety Analysis, Daxiao Liu

Masters Theses

"Observational before-after evaluation of roadway safety treatments effect is a necessary and challenging study area for traffic safety engineers. In decades, empirical Bayesian approach has been widely adopted among researchers in this area. In this approach, the researcher combined before period observation data with a safety performance function estimated from similar groups to estimate the expected number of crashes that would have occurred in the after period without the treatment. Comparing this estimate with the number of crashes observed in the after period, the researcher evaluated the effectiveness of the treatment. This approach accounts for well-known regression-to-the-mean effects. However, as …

Evaluation Of Liquefaction-Induced Lateral Spreading In The Midwest, Kermit Nathanial Applegate

Masters Theses

"The Central United States is home to several seismically active regions: the Wabash Valley Seismic Zone, the South Central Illinois Seismic Zone, and the New Madrid Seismic Zone. All three of these regions are capable of inducing large ground motion throughout the Mississippi Valley and along the eastern border of Missouri. This has been supported by many paleoseismic studies conducted throughout the region, which have identified numerous instances of liquefaction phenomena. The fluvial deposition process associated with the Mississippi river valley makes it a prime location for possible liquefaction and lateral spreading effects. However, there are few studies pertaining to …

Calibration Of Resistance Factors For Axial Capacity Of Driven Pile Into Missouri Soil, Mulugeta Abay Kebede

Masters Theses

"Over the past two decades the load resistance factor design (LRFD) has been accepted by the American Association for Transportation and Highway Officials (AASHTO) for the design of bridges. This approach is now gaining widespread popularity in the United States for substructure bridge design, including the design of driven pile foundations, as the states calibrate the geotechnical resistance factors for local geological conditions and practices. This study presents the geotechnical resistance factors calibrated for axially driven pile using the first-order reliability method (FORM) for the target reliability index of 2.33 and 3.0 based on 64 end-of-drives (EOD) and 22 beginning-of …

Experimental And Modeling Comparison Of Modular Photovoltaic-Thermal Solar Panels, Nicole C. Annis

Masters Theses

"Three different prototype photovoltaic-thermal panels using water as the cooling fluid were tested simultaneously. The first two panels (Panel A and B) consisted of a highly conductive thermal sheeting and different sized copper tubing. The third panel (Panel C) consisted of copper tubing with an aluminum fin. Thermal images were used to verify the heat transfer across the panels and compare the amount of heat radiating off the back of the photovoltaic-thermal panels versus the standard photovoltaic paneleaf Three A type panels were thermally connected in series. Three photovoltaic panels were also tested for an electrical comparison. The purpose of …

Innovative Concrete Bridging Systems For Pedestrian Bridges: Implementation And Monitoring, Kurt Edward Bloch

Masters Theses

"Two precast, prestressed pedestrian bridges were designed for rapid construction in Rolla, MO, utilizing high-strength concrete (HSC) and high-strength self-consolidating concrete (HS-SCC) with a target 28 day compressive strength of 68.9 MPa (10,000 psi) and release compressive strength of 24.1 MPa (3,500 psi). In addition, a glass fiber reinforced polymer (GFRP) bar reinforced deck panel system was utilized in one of the two deck panels on each bridge.

Material properties were tested for compression, elastic modulus, modulus of rupture, splitting tensile strength, creep, and shrinkage following ASTM standards. Instrumentation systems within the spandrel beams and precast deck panels were implemented …

Effects From Filtration, Capping Agents, And Presence/Absence Of Food On The Toxicity Of Silver Nanoparticles To Daphnia Magna, H. Joel Allen, Christopher A. Impellitteri, Dana A. Macke, J. Lee Heckman, Helen C. Poynton, James M. Lazorchak, Shekar Govindaswamy, Deborah L. Roose, Mallikarjuna N. Nadagouda

United States Environmental Protection Agency: Staff Publications

Relatively little is known about the behavior and toxicity of nanoparticles in the environment. Objectives of work presented here include establishing the toxicity of a variety of silver nanoparticles (AgNPs) to Daphnia magna neonates, assessing the applicability of a commonly used bioassay for testing AgNPs, and determining the advantages and disadvantages of multiple characterization techniques for AgNPs in simple aquatic systems. Daphnia magna were exposed to a silver nitrate solution and AgNPs suspensions including commercially available AgNPs (uncoated and coated), and laboratory-synthesized AgNPs (coated with coffee or citrate). The nanoparticle suspensions were analyzed for silver concentration (microwave acid digestions), size …

Unconventional Uses Of Cantilevers For Chemical Sensing In Gas And Liquid Environments, Isabelle Dufour, Fabien Josse, Stephen M. Heinrich, C. Lucat, C. Ayela, F. Ménil, Oliver Brand

Civil and Environmental Engineering Faculty Research and Publications

Microcantilevers used as (bio)chemical sensors are usually coated with a chemically sensitive layer. The coated devices operate either in a static bending regime or in a dynamic flexural mode. While the coated devices operate generally well in both the static and dynamic mode, they do suffer from certain shortcomings depending on the medium of operation and the application, including lack of selectivity and of reversibility of the sensitive coating and a reduced quality factor due to the surrounding medium. In particular, the performance of microcantilevers excited in their standard out-of-plane dynamic mode drastically decreases in viscous liquid media. Moreover, the …

Tapping Environmental History To Recreate America’S Colonial Hydrology, Christopher L. Pastore, Mark B. Green, Daniel J. Bain, Andrea Muñoz-Hernandez, Charles J. Vörösmarty, Jennifer Arrigo, Sara Brandt, Jonathan M. Duncan, Francesca Greco, Hyojin Kim, Sanjiv Kumar, Michael Lally, Anthony J. Parolari, Brian Pellerin, Nira Salant, Adam Schlosser, Kate Zalzal

Civil and Environmental Engineering Faculty Research and Publications

To properly remediate, improve, or predict how hydrological systems behave, it is vital to establish their histories. However, modern-style records, assembled from instrumental data and remote sensing platforms, hardly exist back more than a few decades. As centuries of data is preferable given multidecadal fluxes of both meteorology/climatology and demographics, building such a history requires resources traditionally considered only useful in the social sciences and humanities. In this Feature, Pastore et al. discuss how they have undertaken the synthesis of historical records and modern techniques to understand the hydrology of the Northeastern U.S. from Colonial times to modern day. Such …

An Assessment Of Delivery Risks In Transportation Projects, Velvet Fitzpatrick, Kumares C. Sinha

JTRP Technical Reports

A large number of uncertainties exist in the delivery of highway projects, and it is important to describe the extent so that budgeting and programming can be carried out in a manner that duly accounts for such uncertainties. The study investigates the sources of delivery variability (risk factors) that occur in the period between project proposed date and the letting date. Data on 366 highway projects were collected from the Indiana Department of Transportation Management Information Portal. Using statistical and econometric techniques, the data was analyzed to identify the potential risk factors and to determine the magnitude and direction of …

Initial Expansion Of The Columbia River Tidal Plume: Theory And Remote Sensing Observations, David A. Jay, Edward D. Zaron, Jiayi Pan

Civil and Environmental Engineering Faculty Publications and Presentations

Analysis of the Columbia River tidal plume using Lagrangian frontal equations provides a concise description of the evolution of frontal depth H, velocity U, reduced gravity g', and frontal internal Froude number F (sub R) . Because the estuary mouth is narrow, the initial radial plume motion is supercritical (F (sub R) > 1) for up to 12 hours. Understanding this supercritical phase is vital, because plume properties change rapidly, with strong ecosystem impacts. To analyze this expansion, analytical and numerical models (the latter with three mixing formulations) were tested. Model results are compared to synthetic aperture radar images to verify …