Civil and Environmental Engineering Commons^™

Evaluating Alternative Hydraulic Solutions To Limit Nutrient Contamination Of An Aquifer In Southern California, Jake Mendoza Perry

Master's Theses

Many small communities depend on groundwater sources for drinking water and they often use septic tanks for their sewer system needs. However, nitrates and other pollutants from septic systems can percolate to the aquifers and deteriorate quality of the groundwater, threatening the public health. This study has developed a groundwater model using Visual MODFLOW for an aquifer that is used as a water supply source for the cities of Beaumont and Cherry Valley, California. Septic systems are the suspected major source of nitrate contamination of the aquifer. The model has been developed to clarify the extent of interactions between nitrate …

Effects Of Particulates On Water Meter Accuracy Through Expected Life, B. Skyler Buck, Michael C. Johnson, Steven L. Barfuss

Civil and Environmental Engineering Faculty Publications

Many factors can influence the accuracy of water meters, including age, throughput, water quality, and the presence of particulates in the metered water. These factors can affect various types of meters quite differently depending on the meter's design. This article examines the effects of particulates on various types of meters over their estimated life in a controlled environment. The intent of this study was to assess the effect of particulates on new meter performance and identify trends that may typify meter performance and longevity after being subjected to a slug of particulates. Oscillating-piston (displacement-piston) meters were most affected by a …

Performance Based Analysis Of A Steel Braced Frame Building With Buckling Restrained Braces, Margaux Claire Burkholder

Master's Theses

This paper provides an assessment of the seismic performance of a code-designed buckling restrained braced frame building using the performance-based analysis procedures prescribed in ASCE 41-06. The building was designed based on the standards of the ASCE 7-05 for a typical office building located in San Francisco, CA. Nonlinear modeling parameters and acceptance criteria for buckling restrained brace components were developed to match ASCE 41-06 design standards for structural steel components, since buckling restrained braces are not currently included in ASCE 41-06. The building was evaluated using linear static, linear dynamic, nonlinear static and nonlinear dynamic analysis procedures. This study …

Development Of Best Management Practice Design Guidance For Roadway Applications In Nebraska, Benedict Vacha

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

Runoff from roadways carries pollutants which may be detrimental to aquatic ecosystems. The primary pollutants of concern for roadway runoff are solids and heavy metals, particularly cadmium, copper, and zinc. Roadway runoff falls under the legislation of the Clean Water Act (CWA) via the National Pollutant Discharge Elimination System (NPDES). CWA regulates discharge of nonpoint source pollutants, such as roadway runoff, by issuing permits to public entities which manage Municipal Separate Storm Sewer Systems (MS4s). Part of the Nebraska Department of Roads (NDOR) permitting requirement is to create a design guide for Best Management Practices (BMPs) tailored to remediate roadway …

Development And Recommendations For A Non-Proprietary, High-Tension, Cable End Terminal System, Ryan J. Terpsma

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Cable guardrail systems have been increasing in popularity in recent years due to several perceived benefits over the commonly used W-beam guardrail. A non-proprietary design was desired as an alternative to the many proprietary designs available. A non-proprietary, high-tension cable end terminal was necessary to accompany the non-proprietary, high-tension cable guardrail system under development.

The objective of this research project was to develop design recommendations for a non-proprietary, high-tension cable end terminal. An analysis of several cable guardrail end terminals was undertaken to identify any common features that may prove to be beneficial or detrimental to end terminal designs. Next, …

Static And Impact Load Response Of Reinforced Concrete Beams And Slabs With Nsm-Cfrp Retrofitting, Nakul Ramanna-Sanjeevaiah

Civil & Environmental Engineering Theses & Dissertations

The use of Near-Surface Mounted Carbon Fiber Reinforced Polymer (NSM-CFRP) reinforcement such as carbon FRP strips holds a high potential for increasing the flexural strength of reinforced concrete members. In comparison to externally bonded CFRP laminates, NSM-CFRP reinforcement approach has several advantages. The main advantages include increased stiffness and strength, better bonding, the possibility of anchoring the reinforcement into adjacent members, and minimal installation time. Thus, the structural engineers worldwide are developing a considerable interest in practical applications of the NSM-CFRP reinforcement technique. A considerable amount of research is still needed in order to fully benefit from this method not …

Evaluation Of Hydraulic Conductivity Of Non Aqueous Phase Liquids In Partially Saturated Soils, Chijioke Ekeleme Akamiro

Civil & Environmental Engineering Theses & Dissertations

This study seeks to investigate a problem of predicting the hydraulic conductivity of NAPLs in partially saturated soils and to relate the hydraulic conductivity to basic soil parameters that are either easy to determine or are in wide use. To evaluate hydraulic conductivity in partially saturated soils, previous researchers have focused on flow geometry, soil and chemical properties, etc. used in CHEMFLO program by Nofziger et al., (1989) and saturation equations by such authors as Van Genutchen (1980) and Brooks and Corey (1964). Among those, the soil-water characteristic curve (SWCC) is the most widely used constitutive relations for unsaturated soils …

Integrating Probe Vehicles And Stationary Detector Data To Construct Accurate Cumulative Curves To Study Bottlenecks, Khairul Azfi Anuar

Civil & Environmental Engineering Theses & Dissertations

Advancements in sensors technologies have given researchers and practitioners access to an immense amount of traffic data from multiple types of sensors. However, because of the diversity of the data types, developing a relationship between the different data sources can be challenging. To further complicate the issue, the presence of error or noise makes it difficult to infer any reliable conclusions from the data. To develop a relationship between different data sources, a new methodology is proposed in this thesis for fusing stationary detector data and probe vehicle data to construct an accurate cumulative curve. To remove or to reduce …

The Modified Coastal Storm Impulse Parameter, Sayed Gholamreza Mahmoudpour

Civil & Environmental Engineering Theses & Dissertations

The correlation of the morphological changes to the coast and storm characteristics is among interests of coastal engineers. Better understandings of a storm's potential forces ultimately lead engineers to safer designs and minimize the damages. Therefore, a need to quantify the storm potential forces to a storm parameter is evident. The desired storm parameter is to consider all the relative physical factors and is to present realistic results that then can be proven by actual nature response.

The concept of Coastal Storm Impulse (COSI) parameter was first introduced by Basco and Klentzman (2006) and is based on the conservation of …

Analysis Of Primary-Secondary Incident Events On Urban Freeways, Hongbing Zhang

Civil & Environmental Engineering Theses & Dissertations

The objective of this study is to understand the nature of primary and secondary traffic incidents, assess their impacts and explore the implications in traffic operations, safety, and planning. To achieve the objective, a queue-based secondary incident identification method was developed and applied based on detailed incident, traffic and geometric data sets from Hampton Roads, Virginia. This identification method can overcome the limitations in earlier studies and identify secondary incidents in both road directions. An innovative event categorization defines the term "primary-secondary incident event", as one characterized by a primary incident and one or more associated secondary incidents in both …

Spatial Analysis Of Travel Behavior And Response To Traveler Information, Xin Wang

Civil & Environmental Engineering Theses & Dissertations

Transportation planners have long recognized that it is urgent to integrate emerging spatial analysis with travel behavior studies. A clearer understanding of the spatial interactions among travelers and the complex environment they face has the potential to reap benefits of the ongoing technologies of travel behavior, spatial analysis and Advanced Traveler Information Systems (ATIS).

Considering that spatial patterns have been overlooked in the literature of travel behavior and ATIS, the main objective of this research is to use robust methods of spatial analysis to enhance the understanding of how the associations between traveler decisions, built environment and socio-demographic characteristics are …

Utc Public Transportation Survey, Andra Blanariu

Honors Theses

Chattanooga Area Regional Transportation Authority, the public transit system in Chattanooga, covers most of downtown Chattanooga and its surrounding areas. In the fall of 2011, the enrollment rate of the University of Tennessee at Chattanooga reached over 11000. During the same semester, UTC housed around 2900 students on their campus, which is located in downtown Chattanooga. Based on an on-board survey offered by CARTA in August of 2011, only nineteen percent of their riders are students. While the Chattanooga State Community College is not located downtown, CARTA's survey showed that their students compose the majority of student bus riders. The …

Technical Note: Bias Correcting Climate Model Simulated Daily Temperature Extremes With Quantile Mapping, Bridget Thrasher, Edwin P. Maurer, Philip B. Duffy, Colin Mckellar

Civil, Environmental and Sustainable Engineering

When applying a quantile mapping-based bias correction to daily temperature extremes simulated by a global climate model (GCM), the transformed values of maximum and minimum temperatures are changed, and the diuWhen applying a quantile mapping-based bias correction to daily temperature extremes simulated by a global climate model (GCM), the transformed values of maximum and minimum temperatures are changed, and the diurnal temperature range (DTR) can become physically unrealistic. While causes are not thoroughly explored, there is a strong relationship between GCM biases in snow albedo feedback during snowmelt and bias correction resulting in unrealistic DTR values. We propose a technique …

Factors Influencing Crack-Induced Tensile Strength Of Compacted Soil, Tae Hyung Kim, Tae Hoon Kim, Gi Chun Kang, Louis Ge

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Mode I (tensile) fracture is the most commonly observed failure in Geostructure's resulting from cracks in soil. Direct or indirect tensile tests have been used to evaluate the tensile strength of geomaterials. in this paper, the unconfined penetration device and experimental procedure were modified to reduce measurement errors. It was then used to determine the tensile strength of compacted soil. Factors influencing the tensile strength of the compacted soil, including the plasticity index, rate of loading, and size of specimen were discussed in detail, as well as its reliability. Experimental results indicated that the modified, unconfined penetration technique is sufficiently …

The Cuahsi Community Hydrologic Information System, David G. Tarboton, D. R. Maidment, I. Zaslavsky, Daniel Ames, J. L. Goodall, R. P. Hooper, Jeffery S. Horsburgh

Civil and Environmental Engineering Faculty Publications

No abstract provided.

Interaction Between Electromagnetic Waves And Transport In Saturated Media, Mahsa Azad, Harlan Sangrey, Arvin Farid, Jim Browning, Elisa Barney Smith

Civil Engineering Faculty Publications and Presentations

Air sparging is one of the most popular remediation technologies. However, it is limited to a small radius of influence (ROI) surrounding the air injection well. Hence, there have been several efforts to improve its effectiveness. To study the possibility of improving the effectivity of air sparging electromagnetic (EM) waves, an easily visible analogous problem (dye transport in water) is studied in this paper. In order to quantify the effects of EM stimulation on flow of an inert, nonreactive dye in water, EM-stimulated and unstipulated dye transport experiments tests were performed and compared. To quantify this interaction, both dye transport …

Scale Model Shake Table Testing Of Seismic Earth Pressures In Soft Clay, Robb Moss, R.E. Noche

Civil and Environmental Engineering

There is much uncertainty in seismic earth pressures for basement wall design and retaining wall design in clay soil. The research presented herein uses a scale model testing platform on a 1g shake table to measure the distribution and magnitude of seismic earth pressures for the prototype soil conditions of San Francisco Young Bay Mud (YBM). Similitude scaling of the dynamic soil properties, the wall dimensions, and the input time histories (among other variables) affords accurate modeling of the prototype scale wall. For basement conditions, inertial soil structure interaction (SSI) effects are included in the experiments. Care is taken to …

Using Avhrr-Based Vegetation Health Indices For Estimation Of Potato Yield In Bangladesh, Rahman A., Kaiser Khan, Nir Y. Krakauer, Leonid Roytman, Kogan F.

Publications and Research

We developed a model correlating Advanced Very High Resolution Radiometer (AVHRR)-based Temperature Condition Index (TCI) and Vegetation Condition Index (VCI) with potato yield in Bangladesh. Weekly TCI and VCI Indices for 1993–2005 along with official potato yield statistics were used for model development. We found a strong correlation between inter annual variation in potato yield and TCI and VCI during the critical period of potato growth (vegetative phase and tuber initiation), mid-December to mid-January. Principal component regression (PCR) was used to construct a model to predict potato yield as function of TCI and VCI. The model explained about 75% of …

Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter

USF Tampa Graduate Theses and Dissertations

A simple anaerobic digestion model has been developed for a continuously-stirred tank reactor (CSTR), which links the specific biogas production rate to the food/microorganism ratio (F/M). The model treats the various microbial populations involved in the sequential biological processes involved in anaerobic digestion as a composite and links the entire biomass specific growth rate directly to the specific biogas production rate. The model was calibrated by determining the specific gas production rate for a range of F/M values using a municipal wastewater seed sludge. The model predictions for steady-state biogas production rates were compared to observed biogas production and volatile …

An Analysis Of Turnover Intentions: A Reexamination Of Air Force Civil Engineering Company Grade Officers, Joshua D. Connell

Theses and Dissertations

A potential retention problem is facing company grade officers (CGOs) in the Air Force Civil Engineer (CE) career field. This is due to the stress caused by a demanding workload experienced during a prolonged period of conflict (Iraq and Afghanistan), which is compounded by a reduction in force. The possibility of reduced retention is thus a concern for CE leadership. Based on past research, and the prior study conducted by Riddel (2010), a new model of turnover intentions was developed. The new model expands on Riddel's simplified model of turnover and attempts to focus on key factors that may help …

Asset Management: Roof Maintenance And Facility Energy Retrofits, Joseph P. Dirosario

Theses and Dissertations

The United States Air Force (USAF) needs aggressive new techniques to compliment its asset management of its real estate portfolio. Air Force officials are experiencing budget cuts that have led to degraded facility infrastructure. Two areas of operations in which there are opportunities to improve the asset management of Air Force facilities are roof maintenance and energy retrofits. Information obtained via a geospatial information systems analysis revealed that the current state of the rooftop maintenance program was deficient and supported strategic sourcing as a potential solution to the program's deficiencies. In addition, two methodologies were created to gauge the effectiveness …

Evaluation Of Municipal Wastewater Treatment Plant Activated Sludge For Biodegradation Of Propylene Glycol As An Aircraft Deicer, Justin D. Delorit

Theses and Dissertations

Aircraft deicing fluid used at airport facilities is often collected for treatment or disposal in order to prevent serious ecological threats to nearby surface waters. This study investigated lab scale degradation of propylene glycol (PG), the active ingredient in a common aircraft deicing fluid, by way of a laboratory-scale sequencing batch reactor containing municipal waste water treatment facility activated sludge (AS) performing simultaneous organic carbon oxidation and nitrification. The ability of AS to remove PG was evaluated by studying the biodegradation and sorption characteristics of PG in an AS medium. The results indicate sorption may play a role in the …

Turnover Intentions: A Quantitative Analysis Of Comments From Air Force Civil Engineering Company Grade Officers, Tj E. Gabrielson

Theses and Dissertations

Voluntary turnover is a concern for the military and many other organizations from a financial and performance standpoint. This study applied grounded theory to code and network comments provided by CE officers in 2010. The results of this study found the most influential construct that predicts turnover intentions to be the relationship of OPSTEMPO influencing interrole conflict. This conflict is increased by the workload at home station due to under manning within CE. OPSTEMPO is an important aspect of a military member's decision to stay or leave the service because it was found to interact with a multitude of other …

Firm Fixed Price And Cost Plus Fixed Fee Construction Contracts In Iraq And Afghanistan, Lindsay M. Jaszkowiak

Theses and Dissertations

Firm Fixed Price (FFP) and Cost Plus Fixed Fee (CPFF) contract types have been utilized the most for construction in the Iraq and Afghanistan theaters. Often construction occurs in contested regions that are known to be particularly challenging, unpredictable, and unstable. The objective of this study was to analyze the performance of these two contract types in the contingency environment, and to determine what internal and external factors influence contact success the most. First, the author evaluated existing construction performance data using bivariate analysis and analysis of variance to identify differences in contract type. Next, a quantitative/qualitative questionnaire was administered …

Optimization Of Nanoscale Zero-Valent Iron For The Remediation Of Groundwater Contaminants, Andrew W. E. Mcpherson

Theses and Dissertations

Nanoscale zero-valent iron (nZVI) is an emerging tool for the remediation of groundwater contaminants. The nanoparticles are capable of reductively destroying or immobilizing a wide range of contaminants. Their small size results in a high surface area to mass ratio, making them much more reactive compared to their more-coarse predecessors. Small particle size also allows nZVI particles to be injected directly into contaminated areas via a well, limiting the above-ground footprint and allowing access to contaminated areas that are beyond the reach of some conventional methods. nZVI technology has the potential to facilitate remediation in difficult situations, improve remediation outcomes, …

Biodegradation Of Organophosphate Chemical Warfare Agents By Activated Sludge, Steven J. Schuldt

Theses and Dissertations

Organophosphates (OPs) have been widely used as Chemical Warfare Agents (CWAs) as well as pesticides since World War II and still remain a threat to national security. While efforts have been taken at military installations and civilian communities to secure these chemicals and prevent their misuse, a determined adversary could still obtain and deploy them to injure, kill, or instill terror. The lethal properties of this group of compounds are primarily owed to their irreversible inhibition of the enzyme acetyl cholinesterase (AChE) and thus may alter the human nervous system or affect the hormonal balance of children in particular. In …

Analysis Of Leadership In Energy And Environmental Design® Construction In The Air Force, James M. Rozzoni

Theses and Dissertations

The Air Force uses the Leadership in Energy and Environmental Design (LEED) rating system as a third party verification system to ensure sustainable and resource-conscious facilities. The Federal Government has implemented several mandates in recent years that require certain milestones be met for energy reduction, water conservation, renewable energy use, and so forth. This research aims to determine how the Air Force has implemented LEED through credit analysis, and to better understand why LEED is being used in this way. Using a database of 172 military construction projects, the research evaluates the frequency of credit usage individually and by category. …

The Application Of Sensors On Guardrails For The Purpose Of Real Time Impact Detection, Matthew D. Sturtevant

Theses and Dissertations

The United States roadway system has deteriorated over time due to its age, increasing delays in completing preventative maintenance, and the lack of timely repairs following damage to the infrastructure. Proper asset management drives the need for generalized methods to integrate new sensing capabilities into existing Intelligent Transportation Systems in a time efficient and cost effective manner. In this thesis, we present a methodology for the deployment of new sensors into an existing ITS system. The proposed methodology employs a three phase approach that incorporates data modeling, spatial analysis in Geographic Information Systems, and cost optimization to provide enhanced decision …

Understanding The Impact Of Bead Type On Paint And Thermoplastic Pavement Markings, Joshua D. Hollingsworth

Theses and Dissertations

Each year the United States spends approximately two billion dollars maintaining pavement markings. In addition, an impending Federal policy establishing a minimum retro-reflectivity value for pavement markings has driven asset managers to develop performance models to effectively and efficiently manage these high quantity, low cost assets. Research over the past decade has sought to identify and understand the many factors influencing pavement marking degradation. Despite the fact that reflective glass beads are foundational to pavement marking retro-reflectivity, little research has specifically considered the impacts of bead type. The purpose of this study is to quantify the impact that bead type …

Improving Effectiveness Of Monetary Weapon Systems In Afghanistan, Seth M. Lorimer

Theses and Dissertations

Tenuous political and economic times call for increased oversight and improved results from military counterinsurgency programs in Afghanistan, programs that provide agile non-kinetic weapons, critical for commanders fighting in today's asymmetric battle space. This paper proposes a decision tool for construction projects executed under the Commanders Emergency Response Program, designed to meet the changing demands of fighting an amorphous insurgency among dynamic systems of stakeholders. The research first conducted a system analysis of the CERP project execution process identifying key findings addressing value adding inputs. The research then applies a Causal Chain, borrowed from the Emergency Management field to identify …