Civil and Environmental Engineering Commons^™

Nitrogen Removal And Sustainability Of Vertical Flow Constructed Wetlands For Small Scale Wastewater Treatment, Valerie J. Fuchs

Dissertations, Master's Theses and Master's Reports - Open

The challenge for wastewater professionals is to design and operate treatment processes that support human well being and are environmentally sensitive throughout the life-cycle. This research focuses on one technology for small-scale wastewater treatment: the vertical flow constructed wetland (VFCW), which is herein investigated for the capacity to remove ammonium and nitrate nitrogen from wastewater. Hydraulic regime and presence/absence of vegetation are the basis for a three-phase bench scale experiment to determine oxygen transfer and nitrogen fate in VFCWs. Results show that 90% NH4+-N removal is achieved in aerobic downflow columns, 60% NO3--N removal occurs in anaerobic upflow columns, and …

Post Treatment Alternatives For Stabilizing Desalinated Water, Susaye Douglas

Electronic Theses and Dissertations

The use of brackish water and seawater desalination for augmenting potable water supplies has focused primarily on pre-treatment, process optimization, energy efficiency, and concentrate management. Much less has been documented regarding the impact of post-treatment requirements with respect to distribution system. The goals of this study were to review current literature on post-treatment of permeate water, use survey questionnaires to gather information on post-treatment water quality characteristics, gather operation information, review general capital and maintenance cost, and identify appropriate "lessons learned" with regards to post-treatment from water purveyors participating in the Project. A workshop was organized where experts from across …

A Fuzzy Set Theory Based Methodology For Analysis Of Uncertainties In Stage-Discharge Measurements And Rating Curve, Rajesh R. Shrestha, Slobodan P. Simonovic

Water Resources Research Report

River stage and discharge records are essential for hydrological and hydraulic analyses. While stage is measured directly, discharge value is calculated from measurements of flow velocity, depth and channel cross-section dimensions. The measurements are affected by random and systematic measurement errors and other inaccuracies, such as approximation of velocity distribution and channel geometry with a finite number of measurements. Such errors lead to the uncertainty in both, the stage and the discharge values, which propagates into the rating curve established from the measurements. The relationship between stage and discharge is not strictly single valued, but takes a looped form due …

Biological Treatment Of Dietary Supplement Wastewater, Erick Benjamin Butler

ETD Archive

Dietary supplement wastewater contains higher order polysaccharides such as the complex sugars maltodextrin and low fat milk. These complex sugars contain a significant amount of organic carbon therefore, presence of these sugars can pose threats to the environment if discharged without treatment. While many food processing plants are required to send their waste through wastewater treatment, legislation may require preliminary treatment of these wastes in order to satisfy the effluent discharge requirements. Because of the high organic carbon presence, it would be preferable to use biological treatment methods to reduce the organics present within the system. Microorganisms are capable of …

Artificial Insemination In South American Camelids And Wild Equids, G. P. Adams, M. H. Ratto, C. W. Collins, D. R. Bergfelt

United States Environmental Protection Agency: Publications

An overview of the present status of the use of artificial insemination (AI) in South American camelids and wild equids is offered. Technical aspects of semen collection, dilution and cryopreservation have limited the development and use of AI in camelid and equid species. To-date, efficiency is low but progress has been made and viable offspring have been produced through the use of AI in domestic South American camelids using both fresh and frozen semen. The origin, composition, and function of the viscous component of camelid seminal plasma remain a mystery and an obvious area for future research. A better understanding …

The Solar Transformity Of Petroleum Fuels, S. Bastianoni, D. E. Campbell, R. Ridolfi, F. M. Pulselli

United States Environmental Protection Agency: Publications

Petroleum fuels are the primary energy basis for transportation and industry. They are almost always an important input to the economic and social activities of humanity. Emergy analyses require accurate estimates with specified uncertainty for the transformities of major energy and material inputs to economic and environmental systems. In this study, the oil refining processes in Italy and the United States were examined to estimate the transformity and specific emergy of petroleum derivatives. Based on our assumptions that petroleum derivatives are splits of a complex hydrocarbon mixture and that the emergy is split based on the fraction of energy in …

Foodweb Modeling For Polychlorinated Biphenyls (Pcbs) In The Twelvemile Creek Arm Of Lake Hartwell, South Carolina, Usa, Brenda Rashleigh, M. Craig Barber, David M. Walters

United States Environmental Protection Agency: Publications

PCBs from the Sangamo-Weston Superfund Site near Clemson, South Carolina, USA, were released into the Twelvemile Creek Arm of Lake Hartwell until the early 1990s. Monitoring data have shown that while PCB concentration in sediments declined since 1995, PCB concentrations in fish have remained elevated, e.g., largemouth bass (Micropterus salmoides) concentrations have ranged from 5 to 10 ppm. The EPA aquatic ecosystem model AQUATOX was applied to this system to better characterize foodweb dynamics that lead to biomagnification of PCBs. The model was calibrated with observed fish biomass data. Simulated PCB loading over a 12-year period provided a …

Comparing The Mutagenicity Of Toxaphene After Aging In Anoxic Soils And Accumulating In Fish, James C. Young, Anne D. Freeman, Robert M. Bruce, Douglas Williams, Keith Maruya

United States Environmental Protection Agency: Publications

A test program was conducted to evaluate the mutagenicity of toxaphene residuals extracted from aged soils and from fish collected in creeks near a toxaphene-contaminated site. The ultimate objective was to determine if the residual toxaphene congeners were more or less mutagenic than those in technical- grade toxaphene.The study showed that the mutagenicity of the bioaccumulated toxaphenecongeners in fish, expressed as colony revertants per mg of residual toxaphene, was no greater than that of technical-grade toxaphene.Themutagenicimpactofthetoxapheneresidualsinagedsoilstatistically was less than that for technical-grade toxaphene. Two specific congeners, a hexachlorobornane(labeled Hx-Sd) and a heptachlorobornane (labeled Hp-Sd), were found to accumulate over time …

Missouri River Recovery Program: From Steamboats To Barges: Missouri River Navigation

United States Army Corps of Engineers, Omaha District

Since the early 1800s, the Missouri River has been a thoroughfare for the
transportation of goods. The U.S. government began taking an active interest in Missouri River navigation in 1832, as steamboats became the preferred means of transporting goods and people. On July 3, 1832, Congress authorized channel improvements on the Missouri River. These early river improvements involved mainly addressing obstacles in the river.

Since 1912, the U.S. Army Corps of Engineers (Corps) has managed the river to
allow for modern commercial navigation and trade. This fact sheet will describe the history of navigation on the Missouri River, navigation today, …

Effects Of Aggregate Angularity On Mix Design Characteristics And Pavement Performance, Yong-Rak Kim, Leonardo T. Souza

Mid-America Transportation Center: Final Reports and Technical Briefs

This research targeted two primary purposes: to estimate current aggregate angularity test methods and to evaluate current aggregate angularity requirements in the Nebraska asphalt mixture/pavement specification. To meet the first research objective, various aggregate angularity tests were estimated with the same sets of aggregates and were compared by investigating their characteristics on testing repeatability, cost, testing time, workability, and sensitivity of test results. For the second objective, the effect of aggregate angularity on mixture performance was investigated by conducting laboratory performance tests (the uniaxial static creep test and the indirect tensile fracture energy test) of five mixes designed with different …

Quick Test For Percent Of Deleterious Material, David Newton Richardson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Missouri Department of Transportation (MoDOT) is considering the replacement of its deleterious materials test method (TM-71) with test methods that are more objective. MoDOT contracted with the Missouri University of Science and Technology (Missouri S&T) to develop a system of test methods. Nine quarry/ledge samples representing seven geologic formations (four limestones and three dolomites) were supplied by MoDOT. The ledge samples represented three aggregates each for use in concrete, asphalt, and granular base. Samples with controlled contamination were also tested, bringing the total to 18. The aggregates were subjected to fifteen test methods. This data, coupled with MoDOT historical …

A Refined True Triaxial Apparatus For Testing Unsaturated Soils Under Suction-Controlled Stress Paths, Diego D. Perez-Ruiz

Civil Engineering Dissertations - Archive

A novel, computer-driven, true triaxial (cubical) apparatus has been developed to test unsaturated soil specimens under suction-controlled multi-axial stress paths that are not achievable in a conventional cylindrical apparatus. The cubical cell implemented in this research work is a considerably refined version of those previously reported by Hoyos (1998) and Laikram (2007). The refined version is a servo-controlled, mixed boundary type of cell that allows for full control and real time measurements of matric suction, net principal stresses and soil deformations along a wide range of simple-to-complex stress paths induced on cubical specimens of unsaturated soil. The specimen seats on …

Performance Of Large Scale Steel Fiber Reinforced Concrete Deep Beam With Single Opening Under Monotonic Loading, Carlos Flores

Civil Engineering Theses - Archive

The design of complex, discontinuous stress trajectory regions (D-regions) is complex in natureand cumbersome to design. The performance of a large scale steel fiber reinforced concrete (SFRC)deep beam with single opening under monotonic loading was tested under controlled conditions. Themain objective of this study was to see if Steel Fiber Reinforced Concrete (SFRC), used as a bettermaterial than reinforced concrete (RC) offered an alternate to the cumbersome and iterative stepsinvolved in strut-and-tie (STM) methodology. Additionally, a similar reinforced concrete (RC) specimenwas tested under the same controlled condition designed with classical strut-and-tie model designmethodology reinforced using conventional steel bars.Material testing was …

Theoretical Feasibility Study For A Conceptual Approach To Trenchless Replacement Of Culverts, Diego R. Calderon

Civil Engineering Theses - Archive

Culvert damage and collapses and their renewal alternatives are a raising concern in today's infrastructure topics. In most cases damages are irreversible; however, in many cases opportunities exist to correct and renew. While conventional open-cut construction brings inconvenience to the public, trenchless technology brings a greener, reliable and more socially acceptable alternative to renew culverts. Considering the strong dependency on highway transportation by the American lifestyle, collapses of culverts in major roads may produce chaotic traffic redirections. To reduce this risk, this research sets a path for a construction and feasibility study on a new culvert replacement method based on …

Use Of Electrical Resistivity And Multichannel Analysis Of Surface Wave Geophysical Tomography In Geotechnical Site Characterization Of Dam, Joshua Lee Hubbard

Civil Engineering Theses - Archive

Performance of geotechnical site characterization is a primary function of geotechnical engineers. Generalizations required to extrapolate conventional geotechnical boring data can limit the effectiveness of site assessments. Advancements in geophysical technology have simplified means of data acquisition and interpretation of electrical and seismic testing, allowing a broader audience of practitioners to utilize methods for various engineering and environmental applications. In this study, electrical resistivity and multichannel analysis of surface waves (MASW) seismic geophysical methods are used to expound upon previous geotechnical sampling and in situ testing conducted at an earthen dam site in East Texas. Findings from this study show: …

A New Paradigm In User Equilibrium - Application In Managed Lane Pricing, Asapol Sinprasertkool

Civil Engineering Dissertations - Archive

Ineffective use of the High-Occupancy-Vehicle (HOV) lanes has the potential to decrease the overall roadway capacity during peak periods. Excess capacity in HOV lanes during peak periods can be made available to other types of vehicles, including single occupancy vehicles (SOV) for a price (toll). Such dual use lanes are known as "Managed Lanes." The main purpose of this research is to propose a new paradigm in user equilibrium to predict the travel demand for determining the optimal fare policy for managed lane facilities. Depending on their value of time, motorists may choose to travel on Managed Lanes (ML) or …

Durability Studies On Stabilization Effectiveness Of Soils Containing Different Fractions Of Montmorillonite, Aravind Pedarla

Civil Engineering Theses - Archive

Stabilization of clays with additives like lime and cement has been practiced for several years and worked well in improving the subgrades. Though this practice is used widely, there were cases where the treated subgrades exhibited premature failures. Many departments of transportation (DOT) agencies in the United States have had subgrade failures even after stabilization with chemical additives due to loss of stabilizer over a time period, or a stabilizer being ineffective in some soils. The design based on PI and gradation of soil followed by many DOTs is quite misleading due to the lack of inclusion of basic soil …

Failure Analysis Of A Mechanically Stabilized Earth (Mse) Wall Using Finite Element Program Plaxis, Tahsina Mahmood

Civil Engineering Theses - Archive

Mechanically Stabilized Earth (MSE) retaining walls have been increasingly used in many federal, state and private projects over the last 20 years. MSE walls are reliable, constructible, and cost effective. However, failure of MSE wall has become a problem for all agencies using them. This study presents the failure analysis of a segmental block, MSE retaining wall located in Rockville, Maryland. The top of MSE wall moved about 12 inches to 18 inches. An extensive geotechnical investigation program was undertaken to investigate the MSE wall failure. This study presents the results of investigations to determine the causes of failure. The …

Development And Benefits Of A Leed Project Management Database, Teri Schmig

Civil Engineering Theses - Archive

The U.S. Green Building Council is a non-profit community of industry leaders working to make green buildings available to everyone. The documentation process for achieving Leadership in Energy and Environmental Design (LEED® ) certification is highly complex and more time-consuming than necessary with currently employed systems. This thesis explains the need for development of a relational database as a means to increase the efficiency of the documentation process to meet LEED® requirements. This database will provide the construction project team a relational platform that guides the user through the LEED® administration and certification process. By developing a LEED® specific project …

Development Of Brownfield Database Using Gis, Jubair Hossain

Civil Engineering Theses - Archive

Brownfields are abandoned, idled or underutilized industrial or commercial sites where expansion or redevelopment is complicated by actual or perceived environmental contamination. Brownfields may be as small as a vacant city lot or as large as an abandoned manufacturing facility occupying several hundred acres. The extent of contamination encountered at brownfield sites may range from minor surface debris to extensive, dangerous soil and ground-water contamination. Concerning the communities in which brownfields are located, redevelopment may improve community appearance and image, relieve associated health and environmental concerns and produce a beneficial economic effect through increased property values and employment opportunities.The overall …

Level-Of-Service And Traffic Safety Relationship: An Exploratory Analysis Of Signalized Intersections And Multiland High-Speed Arterial Corridors, Ana Almonte-Valdivia

Electronic Theses and Dissertations

Since its inception in 1965, the Level-of-Service (LOS) has proved to be an important and practical "quality of service" indicator for transportation facilities around the world, widely used in the transportation and planning fields. The LOS rates these facilities' traffic operating conditions through the following delay-based indicators (ordered from best to worst conditions): A, B, C, D, E and F. This LOS rating has its foundation on quantifiable measures of effectiveness (MOEs) and on road users' perceptions; altogether, these measures define a LOS based on acceptable traffic operating conditions for the road user, implying that traffic safety is inherent to …

Resilient Moduli Of Typical Missouri Soils And Unbound Granular Base Materials, David Newton Richardson, Thomas M. Petry, Yu-Ning Louis Ge, Y. P. Han, S. M. Lusher

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The objective of this project is to accurately determine the resilient moduli for common Missouri subgrade soils and unbound granular base materials in accordance with the AASHTO T 307 test method. The test results included moduli data from 27 common subgrade soils out of the 99 Missouri soil associations and from 5 unbound granular bases. These materials were tested at their optimum water content and at an elevated water content, which would normally occur as a worse case scenario during the life of a pavement. The five unbound granular base materials were tested at two different gradations (high and low …

A Comprehensive Study Of Recycled Concrete Aggregates As A Drainable Base Layer For Pavements, Juan Bosquez

Civil Engineering Dissertations - Archive

The use of recycled materials in construction is becoming increasingly popular due to the shortage of raw materials. Coupled with the environmental concerns surrounding the quarrying of natural minerals, waste materials are being considered as viable replacement sources. By recycling waste materials, available landfill space is increased and costs of transportation are reduced. This dissertation study was conducted to evaluate the use of recycled concrete aggregates as flexible base as per the requirements of the Texas Department of Transportation (2004). Two sources of recycled aggregates and one source of natural limestone aggregate were collected from the Dallas/Fort Worth Area and …

Nonlinear Dynamic Analysis Of Hybrid Frames, Dobrinka Radulova

Civil Engineering Theses - Archive

This study proposes a hybrid frame system consisting of rigid and semi-rigid connections subjected to a dynamic loading. Two building geometries are chosen to represent low-rise and high-rise buildings. Multiple locations for placement of semi-rigid connections are proposed, and the hybrid systems with the most efficient energy dissipation are identified. During this analysis, five earthquake records are used to provide a spectrum of frequencies. Five practical semi-rigid connection types and one connection with analytical parameters are also modeled into the selected hybrid combinations by applying zero-length springs at the ends of beams, in which their nonlinear constitutive relation is defined …

Analytical Strip Method To Antisymmetric Laminated Plates, Liecheng Sun

University of Kentucky Doctoral Dissertations

An Analytical Strip Method (ASM) for the analysis of stiffened and non-stiffened antisymmetric laminated composite plates is derived by considering the bending-extension coupling effect for bending, free vibration and buckling. A system of three equations of equilibrium, governing the general response of arbitrarily laminated composite plates, is reduced to a single eighth order partial differential equation in terms of a displacement function. The displacement function is solved in a single series form to determine the displacement, fundamental frequency, and buckling load of antisymmetric cross-ply and angle-ply laminated composite plates. The solution is applicable to rectangular plates with two opposite edges …

Vortex Model Of Open Channel Flows With Gravel Beds, Brian James Belcher

University of Kentucky Doctoral Dissertations

Turbulent structures are known to be important physical processes in gravel-bed rivers. A number of limitations exist that prohibit the advancement and prediction of turbulence structures for optimization of civil infrastructure, biological habitats and sediment transport in gravel-bed rivers. This includes measurement limitations that prohibit characterization of size and strength of turbulent structures in the riverine environment for different case studies as well as traditional numerical modeling limitations that prohibit modeling and prediction of turbulent structure for heterogeneous beds under high Reynolds number flows using the Navier-Stokes equations. While these limitations exist, researchers have developed various theories for the structure …

Investigation Of Damage Detection Methodologies For Structural Health Monitoring, Mustafa Gul

Electronic Theses and Dissertations

Structural Health Monitoring (SHM) is employed to track and evaluate damage and deterioration during regular operation as well as after extreme events for aerospace, mechanical and civil structures. A complete SHM system incorporates performance metrics, sensing, signal processing, data analysis, transmission and management for decision-making purposes. Damage detection in the context of SHM can be successful by employing a collection of robust and practical damage detection methodologies that can be used to identify, locate and quantify damage or, in general terms, changes in observable behavior. In this study, different damage detection methods are investigated for global condition assessment of structures. …

Reduced Visibility Related Crashes In Florida: Crash Characteristics, Spatial Analysis And Injury Severity, Al-Ahad Ekram

Electronic Theses and Dissertations

Roadway crashes related to vision obstruction due to fog/smoke (FS) conditions constitute a challenge for traffic engineers. Previous research efforts mostly concentrated on the snow and rain related crashes. Statistics show that Florida is among the top three states in terms of crashes due to vision obstruction by FS. This research culminated in a comprehensive study of fog and smoke related crashes in the state of Florida. The analysis took into account the crashes that occurred between 2003 and 2007 on Florida state roads. Spatial analysis and injury severity analysis have been conducted and significant results have been identified. The …

The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe

Electronic Theses and Dissertations

The microscopic traffic simulation program VISSIM is a powerful tool that has been used by transportation engineers and urban planners around the world. A VISSIM simulation is meant to depict the performance of the physical road network through the use of modeling tools and behavioral parameters. The process which gets the model to the point of matching real world conditions is called calibration and requires a means of relating the real world to the simulated world. The topic of this thesis discusses a new means of calibration using the two-fluid model. The two-fluid model is a macroscopic modeling technique which …

Work Zone Effects On Performance Of A Toll Plaza, Jingyu Liu

Electronic Theses and Dissertations

No-lane closure workzone is typical during the construction of open road tolling lanes of a toll plaza. The influence of no-lane closure on toll plazas' performance is unknown because very few studies have been conducted to address this topic. The open road tolling (ORT) has become the new trend of operating an efficient toll plaza. So, the upgrading of a toll plaza from gated E-pass to open road E-pass has become common. The better the toll plaza authority knows about the influence of this construction and congestion effects, the better it can serve the costumers. This project mainly deals with …