Civil and Environmental Engineering Commons^™

The Effects Of Assumption On Subspace Identification Using Simulation And Experiment Data, Yoonhwak Kim

Electronic Theses and Dissertations

In the modern dynamic engineering field, experimental dynamics is an important area of study. This area includes structural dynamics, structural control, and structural health monitoring. In experimental dynamics, methods to obtain measured data have seen a great influx of research efforts to develop an accurate and reliable experimental analysis result. A technical challenge is the procurement of informative data that exhibits the desired system information. In many cases, the number of sensors is limited by cost and difficulty of data archive. Furthermore, some informative data has technical difficulty when measuring input force and, even if obtaining the desired data were …

Chemophysical Characteristics And Application Of Biosorption Activated Media (Bam) For Copper And Nutrient Removal In Stormwater Management, Jamie Jones

Electronic Theses and Dissertations

For high groundwater table areas, stormwater wet detention ponds are utilized as the preferred stormwater management throughout the state of Florida. Previous research has found that accumulations of nutrients, algae, heavy metals, pesticides, chlorophyll a, fecal coliform bacteria and low concentrations of dissolved oxygen (DO) are common characteristics of stormwater wet detention ponds. Although these pollutant levels are not regulated within the ponds, states are required to compute the pollutant load reductions through total maximum daily load (TMDL) programs to meet the water quality requirements addressed by the Clean Water Act (CWA). In this study, field sampling data of stormwater …

Multi-Physics Modeling Of Geomechanical Systems With Coupled Hydromechanical Behaviors, Ahmad Mohamed

Electronic Theses and Dissertations

Geotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the consolidation of porous material. The objective of this research wasto demonstrate the advantages of using hydromechanical models to estimate deformation and pore water pressure of porous materials by comparing with mechanical-only models. Firstly, extensive literature survey was conducted …

Integrated Data Fusion And Mining (Idfm) Technique For Monitoring Water Quality In Large And Small Lakes, Benjamin Vannah

Electronic Theses and Dissertations

Monitoring water quality on a near-real-time basis to address water resources management and public health concerns in coupled natural systems and the built environment is by no means an easy task. Furthermore, this emerging societal challenge will continue to grow, due to the ever-increasing anthropogenic impacts upon surface waters. For example, urban growth and agricultural operations have led to an influx of nutrients into surface waters stimulating harmful algal bloom formation, and stormwater runoff from urban areas contributes to the accumulation of total organic carbon (TOC) in surface waters. TOC in surface waters is a known precursor of disinfection byproducts …

Evaluating The Use Of Recycled Concrete Aggregate In French Drain Applications, Zachary Behring

Electronic Theses and Dissertations

Recycled concrete aggregate (RCA) is often used as a replacement of virgin aggregate in road foundations (base course), embankments, hot-mix asphalt, and Portland cement concrete. However, the use of RCA in exfiltration drainage systems, such as French drains, is currently prohibited in many states of the U.S. The French drain system collects water runoff from the road pavement and transfers to slotted pipes underground and then filters through coarse aggregate and geotextile. The primary concerns with using RCA as a drainage media are the fines content and the precipitation of calcium carbonate to cause a reducing in filter fabric permittivity. …

Assessment, Optimization, And Enhancement Of Ultrafiltration (Uf) Membrane Processes In Potable Water Treatment, Christopher Boyd

Electronic Theses and Dissertations

This dissertation reports on research related to ultrafiltration (UF) membranes in drinking water applications. A pilot-scale investigation identified seasonal surface water quality impacts on UF performance and resulted in the development of a dynamic chemically enhanced backwash protocol for fouling management. Subsequent analysis of UF process data revealed limitations with the use of specific flux, transmembrane pressure (TMP), and other normalization techniques for assessing UF process fouling. A new TMP balance approach is presented that identifies the pressure contribution of membrane fouling and structural changes, enables direct process performance comparisons at different operating fluxes, and distinguishes between physically and chemically …

Evaluation Of The Biodegradability And Toxicity Of Pca And Mpca, Juan Rueda

Electronic Theses and Dissertations

The main types of hypergolic propellants used at Kennedy Space Center (KSC) are hydrazine (HZ) and monomethylhydrazine (MMH). HZ and MMH are classified as hazardous materials and they are also known to be potentially carcinogenic to humans; therefore, handling these substances and their waste is strictly regulated. The wastes streams from HZ and MMH have been estimated to be the main hazardous wastes streams at KSC. Currently at KSC these wastes are first neutralized using citric acid and then they are transported on public roads for incineration as hazardous materials. A new method using alpha ketoglutaric acid (AKGA) was proposed …

Development Of A Chemical Kinetic Model For A Fluidized-Bed Sewage Sludge Gasifier, Wyatt Champion

Electronic Theses and Dissertations

As the need for both sustainable energy production and waste minimization increases, the gasification of biomass becomes an increasingly important process. What would otherwise be considered waste can now be used as fuel, and the benefits of volume reduction through gasification are seen in the increased lifespan of landfills. Fluidized-bed gasification is a particularly robust technology, and allows for the conversion of most types of waste biomass. Within a fluidized-bed gasifier, thermal medium (sand) is heated to operating temperature (around 1350°F) and begins to fluidize due to the rapid expansion of air entering the bottom of the reactor. This fluidization …

Near-Road Dispersion Modeling Of Mobile Source Air Toxics (Msats) In Florida, Kurt Westerlund

Electronic Theses and Dissertations

There is a growing public concern that emissions of mobile source air toxics (MSATs) from motor vehicles may pose a threat to human health. At present, no state or federal agencies require dispersion modeling of these compounds, but many agencies are concerned about potential future requirements. Current air pollution professionals are familiar with Federal Highway Administration (FHWA) and U.S. Environmental Protection Agency (EPA) requirements for dispersion modeling to produce predicted concentrations for comparison with appropriate standards. This research examined a method in which the potential near-road concentrations of MSATs were calculated. It was believed that by assessing MSATs in much …

Study Of The Effect Of Surface Morphology On Mass Transfer And Fouling Behavior Of Reverse Osmosis And Nanofiltration Membrane Processes, Yuming Fang

Electronic Theses and Dissertations

Reverse osmosis (RO) and nanofiltration (NF) membranes are pressure driven, diffusion controlled process. The influence of surface characteristics on membrane process performance is considered significant and is not well understood. Current mass transport models generally assume constant mass transfer coefficients (MTCs) based on a homogeneous surface. This work evaluated mass transfer processes by incorporating surface morphology into a diffusion-based model assuming MTCs are dependent on the thickness variation of the membrane’s active layer. To mathematically create such a surface layer, Gaussian random vectors embedded in a software system (MATLAB) were used to generate a three-dimensional ridge and valley active layer …

A Systems Approach To Sustainable Energy Portfolio Development, Saeed Hadian

Electronic Theses and Dissertations

Adequate energy supply has become one of the vital components of human development and economic growth of nations. In fact, major components of the global economy such as transportation services, communications, industrial processes, and construction activities are dependent on adequate energy resources. Even mining and extraction of energy resources, including harnessing the forces of nature to produce energy, are dependent on accessibility of sufficient energy in the appropriate form at the desired location. Therefore, energy resource planning and management to provide appropriate energy in terms of both quantity and quality has become a priority at the global level. The increasing …

Non-Destructive Evaluation Of Concrete Structures Using High Resolution Digital Image And Infrared Thermography Technology, Azusa Watase

Electronic Theses and Dissertations

As existing bridge structures age, they are susceptible to the effects of deterioration, damage and other deleterious processes. These effects hamper the capacity and efficiency of transportation networks and adversely impact local, regional and national economic growth. As a result, bridge authorities and other professionals have become more sensitive to maintenance issues related to this aging infrastructure. While highway bridge condition have been monitored by visual inspection, non-destructive evaluation (NDE) technologies have also been developing and they are expected to be utilized for effective management of highway bridges or other civil infrastructure systems. Efficient use of these technologies saves time …

Development Of An Aquaponics Research Program, Richard W. Marklin Jr., Margaret Mathison, Brooke K. Mayer, Mark L. Nagurka, Vikram Cariapa, Michael Schläppi

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.

Field Performance Of Alternative And Cost Efficient Cast In Place And Precast Prestressed Concrete Bridge Approach Slabs, Nathan Price Muncy

Masters Theses

"In December of 2010, the Missouri Department of Transportation (MoDOT) investigated alternative cost-efficient bridge approach slabs (BASs). New BAS designs were subsequently developed and had a projected cost savings up to twenty-four percent with anticipated equal or better structural performance. A precast-prestressed (PCPS) BAS was introduced as an alternative to traditional BASs that offers advantages such as rapid construction and improved long-term durability. The three new BAS designs were implemented into in-situ bridge projects by MoDOT and the field performance was evaluated within this research study.

Field testing of each BAS was performed using two MoDOT HS20 trucks. Various instrumentation …

Characterization Of Nano-Scale Aluminum Oxide Transport Through Porous Media, Sasha Norien Norwood

Dissertations and Theses

Land application of biosolids has become common practice in the United States as an alternative to industrial fertilizers. Although nutrient rich, biosolids have been found to contain high concentrations of emerging contaminants (e.g. pharmaceuticals, personal care products) while containing a significant fraction of inorganic nano-scale colloidal materials such as oxides of iron, titanium, and aluminum.

Given their reactivity and small size, there are many questions concerning the potential migration of these nano-sized colloidal materials through the soil column and into our surface and groundwater bodies. Transport of emerging pollutants of concern through the soil column, at minimum, is impacted by …

The Relationship Between Traffic Signals And Pedestrian, Bicyclist And Transit User Exposure In Urban Areas, Courtney Natasha Slavin

Dissertations and Theses

Improving the efficiency of traffic operations along arterials is currently a priority for many agencies as their roadway infrastructure is built out to the largest possible capacity within the urban environment. Many advanced systems are being implemented to optimize traffic signal timing. Air quality is typically not a consideration when these decisions are made. The relationship between exposure to air pollution and traffic signal timing has not been fully explored by other researchers. This study is the first research effort to combine detailed traffic signal timing data (at 5 second intervals) and air pollutant exposure data. Results show that longer …

Characterization Of A Coal Fly Ash-Cement Slurry By The Absolute Foam Index, Melanie Kueber Watkins

Dissertations, Master's Theses and Master's Reports

This dissertation established a standard foam index: the absolute foam index test. This test characterized a wide range of coal fly ash by the absolute volume of air-entraining admixture (AEA) necessary to produce a 15-second metastable foam in a coal fly ashcement slurry in a specified time. The absolute foam index test was used to characterize fly ash samples having loss on ignition (LOI) values that ranged from 0.17 to 23.3 %wt. The absolute foam index characterized the fly ash samples by absolute volume of AEA, defined as the amount of undiluted AEA solution added to obtain a 15-minute endpoint …

Futures Methodology As An Analysis And Planning Tool Within The Commercial Real Estate Industry, An Interpretative Study, Dominika Brodowicz

Doctoral

Currently, the majority of methods used in the commercial real estate analysis and planning processes have retrospective and quantitative roots and are based on historic data and trend extrapolation. This approach is based on the assumption that the relationships among key commercial property market variables and trends are constant and develop in a predictable manner into the future. Meanwhile, contemporary real estate companies, which are the subject of this study, are faced with rapid change, often of a discontinuous nature, in their external and internal environments. Furthermore, some of the challenges facing this industry, like social sustainability and a shift …

On The Concept Of Earthquake Resistant Hybrid Steel Frames, Seyed Mohammad Razavi

Civil Engineering Dissertations - Archive

The concept of hybrid steel frame system is presented in which mixtures of fully-rigid and semi-rigid steel connections are used in the 3-, 9- and 20-story SAC frames. Several different patterns and locations of semi-rigid connection replacements within the frame are examined in order to identify hybrid frames with the best seismic performance. The effective connection stiffness is identified by performing a parametric study on the initial stiffness of the semi-rigid connections. Then, the cyclic behavior of the connections with the most effective stiffness is obtained using nonlinear finite element analysis. Inelastic dynamic analyses are conducted on the proposed selected …

The Uplift Resistance Of Spartina Alterniflora In A Louisiana Salt Marsh, James Madison Bouanchaud Iii

LSU Master's Theses

The uprooting resistance of Spartina Alterniflora was measured in Terrebonne Bay and Bay Jimmy, both of which are located in Louisiana. The parameters collected included plant uprooting resistance, stem diameter, and stem height. Seasonal variations and site specific properties were considered. A device was designed and constructed that was able to perform the specific testing under the constraints of the field site. The device consisted of a winch mounted to a tripod and connected to an inline load cell to measure the uprooting resistance. The data sets were analyzed to determine the relationship between the uprooting resistance and the physical …

Wind Loading On Trees Integrated With A Building Envelope, Aly Mousaad Aly, Alberto Zasso, Girma Bitsuamlak, Alberto Nicola Longarini, Arindam Gam Chowdhury

Faculty Publications

With the sustainability movement, vegetated building envelopes are gaining more popularity. This requires special wind effect investigations, both from sustainability and resiliency perspectives. The current paper focuses on wind load estimation on small- and full-scale trees used as part of green roofs and balconies. Small-scale wind load assessment was carried out using wind tunnel testing in a global-effect study to understand the interference effects from surrounding structures. Full-scale trees were investigated at a large open-jet facility in a local-effect study to investigate the wind-tree interaction. The effect of Reynolds number combined with shape change on the overall loads measured at …

Enhancing Selective Decomposition Of Ibuprofen Onto Porous Tio₂ Nanoparticles, Abolfazl Zakersalehi

Civil Engineering Theses - Archive

Advanced oxidation technologies have gained tremendous attention for water treatment purposes after demonstration of insufficient efficiency of conventional systems for removal of many emerging chemicals of concern. Among AOTs, a TiO2-UV system is one of the most promising approaches due to its green properties and its effectiveness in generation of extremely oxidizing species such as hydroxyl radicals. However it has been demonstrated that non-selectivity of HRs in decomposition of organic compounds results in parallel decomposing of naturally abundant organic matter (NOM) along with toxic target contaminant, which significantly decreases the decomposition rate of target contaminants. Despite a great amount of …

Investigations To Develop Field Stabilization Methods To Mitigate Surficial Slope Failures, Minh Le

Civil Engineering Dissertations - Archive

Surficial slope failures induced by rainfall have been studied for many years. Current research supported by The United States Army Corps of Engineers (USACE) is undertaken at the University of Texas at Arlington on two sites, Joe Pool Dam and Grapevine Dam located in the Fort Worth district. The objective of the project is to find the best stabilization method to mitigate those failures. A testing area of 5 sections (one control and four treated) was established on each site with used admixtures of 20% compost, 4% lime with 0.30% polypropylene fibers, 8% lime with 0.15% polypropylene fibers, and 8% …

Hydraulic Performance Evaluation Of Different Recirculation Systems For Elr / Bioreactor Landfills, Shahed R. Manzur

Civil Engineering Dissertations - Archive

The major aspect of bioreactor landfill is the addition of liquid and recirculation of collected leachate back into the waste mass through the subsurface Leachate Recirculation System (LRS). The leachate recirculation system consists of the perforated recirculation pipes placed inside horizontal trenches and the permeable beds with different orientation. The application of high permeability material (shredded tire chips, broken glass, pea gravel) in landfills is an emerging technology to distribute the moisture over a wider area in a shorter period of time. Horizontal or vertical perforated pipes are installed in bioreactor landfills as LRS with an expectation of uniform moisture …

Large Diameter Steel Pipe Field Test Using Controlled Low Strength Material And Staged Construction Modeling Using 3-D Nonlinear Finite Element Analysis, Franciele Bellaver

Civil Engineering Theses - Archive

Using finite element methods and field tests, an extensive study on selected steel pipes is devised for the Integrated Pipeline Project in Dallas-Fort Worth, Texas. The project integrates Tarrant Regional Water District (TRWD) existing pipelines to the Dallas system along 150 miles. Field test of buried pipes, monitoring the pipe in different trench conditions is extremely valuable in predicting the displacement of the pipe during construction stages and during its lifetime. The field instrumentation monitors the circular displacements and strains of a buried steel pipe with an outside diameter (O.D.) of 84 in. and 0.375 in. thickness in three different …

Determination Of Safe Roadway Buffer Width To Protect Human Health From No2 Exposure: A Case Study For Grand Prairie, Tx, Hetal Bhatt, Melanie L. Sattler, Stephen P. Mattingly

Civil Engineering Faculty Publications - Archive

No abstract provided.

Sustainable Slope Stabilization Using Recycled Plastic Pin In Texas, Mohammad Sadik Khan

Civil Engineering Dissertations - Archive

Shallow slope failures are predominant in the North Texas area and pose significant maintenance problems for the Texas Department of Transportation (TxDOT). As a cost effective alternative, the Recycled Plastic Pin (RPP) can be utilized to stabilize the shallow slope failure. RPP are fabricated from recycled plastics and waste materials (i.e. polymers, sawdust, and fly ash). It is a lightweight material and less susceptible to chemical and biological degradation than alternative reinforcing element. RPPs are driven into the slope face, which provide additional resistance along the slip surface and increase the factor of safety. The current study summarized the remediation …

Using Gis To Delineate Headwater Stream Origins In The Appalachian Coal-Belt Region Of Kentucky, Jonathan A. Villines

Theses and Dissertations--Biosystems and Agricultural Engineering

Human activity such as surface mining can have substantial impacts on the natural environment. Performing a Cumulative Hydrologic Impact Assessment (CHIA) of such impacts on surface water systems requires knowing the location and extent of these impacted streams. The Jurisdictional Determination (JD) of a stream’s protected status under the Clean Water Act (CWA) involves locating and classifying streams according to their flow regime: ephemeral, intermittent, or perennial. Due to their often remote locations and small size, taking a field inventory of headwater streams for surface mining permit applications or permit reviews is challenging. A means of estimating headwater stream location …

Safety Performance Evaluation Of The Non-Blocked Midwest Guardrail System, Kevin D Schrum, Karla A. Lechtenberg, Robert W. Bielenberg, Scott K. Rosenbaugh, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Modeling Of Shear Strengthening Of Reinforced Concrete Beams Retrofitted With Externally Bonded Fiber Reinforced Polymers, Srinivasa Anusha Bellamkonda

LSU Master's Theses

This thesis presents a study on the shear retrofit of reinforced concrete (RC) beams with externally bonded fiber reinforced polymers (FRP), since it is very important for RC beam to have a shear strength that is higher than the flexural strength in order to ensure ductile flexural failure mode. The study proposes a new model to predict the FRP shear strength contribution for different modes of failure, i.e., bending, shear with FRP rupture, shear with FRP debonding, and mixed shear-flexure and various retrofit techniques, i.e., side-bonding, U-jacketing, and full wrapping. The proposed model is compared to other existing models for …