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Full-Text Articles in Civil and Environmental Engineering

Second-Order Perturbation Analysis Of The St. Venant Equations In Relation To Bed-Load Transport And Equilibrium Scour Hole Development, Frans Joseph Lambrechtsen Dec 2013

Second-Order Perturbation Analysis Of The St. Venant Equations In Relation To Bed-Load Transport And Equilibrium Scour Hole Development, Frans Joseph Lambrechtsen

Theses and Dissertations

This analysis is an expansion of research done by Rollin Hotchkiss during his Ph.D work. The research uses fluid flow, sediment transport, and perturbation theory to predict where scour will occur in a variable-width channel. The resulting equations also determine equilibrium scour depth based upon the stream bed elevation derived from a dimensionless bed slope equation. Hotchkiss perturbed the width of the channel using a second order Taylor Series perturbation but neglected second order terms. The present work follows the same procedures as Hotchkiss but maintains the second order terms. The primary purpose is to examine how the additional terms …


Deicer Usage On Concrete And Asphalt Pavements In Utah, Chase David Thomas Dec 2013

Deicer Usage On Concrete And Asphalt Pavements In Utah, Chase David Thomas

Theses and Dissertations

The objectives of this research were to 1) compile winter maintenance data for the Utah Department of Transportation (UDOT) to directly compare concrete and asphalt pavements with regards to deicer usage and 2) determine if there is a statistical difference in deicer usage on concrete and asphalt pavements. To this end, three data sources were consulted for this research: Material Maintenance Quality Assurance (MMQA) database, UDOT road database, and Google Maps. The final compiled data set prepared for analysis in this research contained deicer quantities by deicer type, pavement surface areas by pavement material type, traffic, longitude, latitude, and elevation …


Hot Spot Identification And Analysis Methodology, Jacob S. Farnsworth Nov 2013

Hot Spot Identification And Analysis Methodology, Jacob S. Farnsworth

Theses and Dissertations

The Utah Department of Transportation (UDOT) Traffic and Safety Division continues to advance the safety of roadway sections throughout the state. To aid UDOT in meeting their goal the Department of Civil and Environmental Engineering at Brigham Young University (BYU) has worked with the Statistics Department in developing analysis tools for safety. The most recent of these tools has been the development of a hierarchical Bayesian Poisson Mixture Model (PMM) statistical model of traffic crashes and safety on UDOT roadways statewide and the integration of the results of this model in a Geographic Information System (GIS) framework. This research focuses …


Internal Curing Of Concrete Bridge Decks In Utah: Mountain View Corridor Project, Joseph Michael Yaede Jul 2013

Internal Curing Of Concrete Bridge Decks In Utah: Mountain View Corridor Project, Joseph Michael Yaede

Theses and Dissertations

The objectives of this research were to 1) monitor in-situ moisture and diffusivity for both conventional concrete and concrete containing pre-wetted lightweight fine aggregate (LWFA), 2) compare deck performance in terms of early-age cracking, compressive strength, and chloride ingress, and 3) compare concrete properties in terms of compressive strength, chloride permeability, elastic modulus, and water content in the laboratory using cylinders cast in the field at the time of deck construction. The research involved field and laboratory evaluations of four newly constructed bridge decks located in northern Utah, two constructed using conventional concrete and two constructed using pre-wetted LWFA to …


A Comparative Analysis Of Energy Modelingmethods For Commercial Buildings, Spencer Mark Salmon Jul 2013

A Comparative Analysis Of Energy Modelingmethods For Commercial Buildings, Spencer Mark Salmon

Theses and Dissertations

This thesis researched the accuracy of measured energy data in comparison to estimated hand calculation data and estimated building energy performance simulation data. In the facility management industry, there is minimal evidence that building energy performance software is being used as a benchmark against measured energy usage within a building. Research was conducted to find examples of measured energy data compared to simulated data. The study examined the accuracy of a simulation software and hand calculations to measured energy data. Data suggests that comparisons may be made between building energy performance simulated data and measured data, though comparisons are solely …


Modeling And Optimization Of Space Use And Transportation For A 3d Walkable City, Bradley R. Mecham Jul 2013

Modeling And Optimization Of Space Use And Transportation For A 3d Walkable City, Bradley R. Mecham

Theses and Dissertations

This thesis presents an investigation of a new three-dimensional urban form where walking distances are less than a half-mile and congestion is minimal. The car-free urban form investigated herein is a city composed of skyscrapers massively interconnected with skybridges at multiple levels. The investigation consists of optimizing space use arrangement, skybridge presence or absence, and elevator number to simultaneously minimize total travel time, skybridge light blockage, and elevator energy usage in the city. These objectives are evaluated using three objective functions, the most significant of which involves a three-dimensional, pedestrian-only, three-step version of the traditional four-step planning model. Optimal and …


Large-Scale Testing Of Passive Force Behavior For Skewed Abutments With High Width-Height Ratios, Katie Noel Palmer Jul 2013

Large-Scale Testing Of Passive Force Behavior For Skewed Abutments With High Width-Height Ratios, Katie Noel Palmer

Theses and Dissertations

The effects of seismic forces and thermal expansion on bridge performance necessitate an accurate understanding of the relationship between passive force and backwall deflection. In past case studies, skewed bridges exhibited significantly more damage than non-skewed bridges. These findings prompted studies involving numerical modeling, lab-scale tests, and large-scale tests that each showed a dramatic reduction in passive force with increased skew. Using these results, a correlation was developed between peak passive force and backwall skew angle. The majority of these tests had length to height ratios of 2.0; however, for several abutments in the field, the length to height ratio …


An Analysis Of The Provo River Decree And Its Current Application To Provo Area Water Rights, Karsten Eugene Busby Jul 2013

An Analysis Of The Provo River Decree And Its Current Application To Provo Area Water Rights, Karsten Eugene Busby

Theses and Dissertations

Water scarcity in the west has created a long history of conflict. When Utah was settled, laws were instituted (both officially and otherwise) that allowed water users to use streams and springs in efficient ways without causing harm to other users. The Provo River Decree is a physical example of local water law that has been in place for almost a hundred years. While many changes have arisen in its area of jurisdiction, it is still drawn upon to determine water rights. Ambiguity, rigidity, and overall changes to use patterns have limited the application of the decree to present situations. …


Compositional And Structural Properties Of Emulsion-Treated Base Material: 7800 South In West Jordan, Utah, Lisa Renay Gurney Jun 2013

Compositional And Structural Properties Of Emulsion-Treated Base Material: 7800 South In West Jordan, Utah, Lisa Renay Gurney

Theses and Dissertations

The objectives of this research were 1) to examine correlations between compositional and structural properties of emulsion-treated base (ETB) layers, determine which of these factors exhibit the greatest spatial variability, and determine if significant differences exist between different test sections on a given project and 2) to investigate temporal trends in the structural properties of base materials treated with asphalt emulsion and to assess the rate at which ETB design properties are achieved. The research conducted in this study focused on testing of the ETB layer constructed on 7800 South (SR-48) in West Jordan, Utah. The research conducted in this …


Evaluating The Effects Of Non-Anonymity On Student Team-Member Evaluations, Taylor Robert Smith Jun 2013

Evaluating The Effects Of Non-Anonymity On Student Team-Member Evaluations, Taylor Robert Smith

Theses and Dissertations

This thesis investigates the effect that non-anonymity has upon student team-member evaluations; more specifically, it looked at how to create conditions of openness and honesty in which students will readily give and receive constructive criticism. The central hypothesis of this research is that if students are taught and prepared to properly give and receive constructive criticism, and have multiple opportunities to do so, non-anonymous feedback is the most effective and desirable. In order to gauge the effects of non-anonymity, eight specific hypotheses relating to different aspects of the feedback process were tested. Predictions were made as to the effects upon …


Comparison Of Performance-Based Liquefaction Initiation Analyses Between Multiple Probabilistic Liquefaction Models Using The Standard Penetration Test, Alexander David Wright Jun 2013

Comparison Of Performance-Based Liquefaction Initiation Analyses Between Multiple Probabilistic Liquefaction Models Using The Standard Penetration Test, Alexander David Wright

Theses and Dissertations

For the most recent and correct article, please click here: http://ascelibrary.org/doi/abs/10.1061/9780784412787.086

This study examines the use of performance-based approaches in liquefaction hazard analysis. Two new methods of performance-based liquefaction initiation analysis are proposed which use the works of Juang et al. (2012) and Boulanger and Idriss (2012). Further advances are made by incorporating the performance-based magnitude scaling factors as proposed by Cetin et al. (2012). Using these new equations a comparative study is made between the three methods. Further comparisons are made between the performance-based approaches and the more widely used deterministic approaches. The comparisons reveal that on average for …


Accuracy Of A Simplified Analysis Model For Modern Skyscrapers, Jacob Scott Lee Jun 2013

Accuracy Of A Simplified Analysis Model For Modern Skyscrapers, Jacob Scott Lee

Theses and Dissertations

A new simplified skyscraper analysis model (SSAM) was developed and implemented in a spreadsheet to be used for preliminary skyscraper design and teaching purposes. The SSAM predicts linear and nonlinear response to gravity, wind, and seismic loading of "modern" skyscrapers which involve a core, megacolumns, outrigger trusses, belt trusses, and diagonals. The SSAM may be classified as a discrete method that constructs a reduced system stiffness matrix involving selected degrees of freedom (DOF's). The steps in the SSAM consist of: 1) determination of megacolumn areas, 2) construction of stiffness matrix, 3) calculation of lateral forces and displacements, and 4) calculation …


Evaluating The Safety Effects Of Signal Improvements, Ashley Lynn Dowell May 2013

Evaluating The Safety Effects Of Signal Improvements, Ashley Lynn Dowell

Theses and Dissertations

As a result of high crash frequencies on roadways, transportation safety has become a high priority for the United States Department of Transportation and the Utah Department of Transportation. A large percentage of fatal and injury crashes on roadways occur at intersections and traffic signals have been implemented to reduce these severe crashes. There is a need to evaluate the effectiveness of the traffic signal improvements through the development of Crash Modification Factors (CMFs). Recent research has shown that traditional safety evaluation methods have been inadequate in developing CMFs. In recent years, Bayesian statistical methods have been utilized in traffic …


Development Of Peptide Nanotube-Modified Biosensors For Gas-Phase Organophosphate Detection, Peter A . Baker Mar 2013

Development Of Peptide Nanotube-Modified Biosensors For Gas-Phase Organophosphate Detection, Peter A . Baker

Theses and Dissertations

Vapor-phase detection of the model organophosphate malathion was achieved using enzymes encapsulated in peptide nanotubes and attached to gold screen-printed electrodes. Malathion was chosen as the model for this experiment because its binding mechanism with acetylcholinesterase (AChE) is identical to its more potent counterparts (such as sarin or VX), but it has an extremely low human toxicity, which makes it both practical and easy to use. The peptide nanotubes had horseradish peroxidase encapsulated inside and were coated with both acetylthiocholine (ASCh) and AChE on the outside. ASCh hydrolysis, which produces thiocholine, was catalyzed by the AChE. The thiocholine was then …


An Analysis Of Factors That Influence The Success Of Expeditionary Civil Engineer Hub-And-Spoke Organizations, Joshua A . Hager Mar 2013

An Analysis Of Factors That Influence The Success Of Expeditionary Civil Engineer Hub-And-Spoke Organizations, Joshua A . Hager

Theses and Dissertations

Expeditionary Air Force Civil Engineer support to recent operations in southwest Asia created a unique organizational learning environment, particularly related supporting the general engineering requirements of geographically separated units in a manpower-constrained contingency environment. One of the direct results of this organizational learning was the hub-and-spoke expeditionary engineer unit featuring elements of both RED HORSE and Prime BEEF capabilities operating with theater-wide visibility of infrastructure requirements. This study acquired insights from literature and a purposeful sample of subject matter experts about operational advantages this hub-and-spoke unit offered compared to those offered by strictly legacy organizational models. The research used a …


Successfully Implementing Net-Zero Engergy Policy Through The Air Force Military Construction Program, D. Gavin Brost Mar 2013

Successfully Implementing Net-Zero Engergy Policy Through The Air Force Military Construction Program, D. Gavin Brost

Theses and Dissertations

The U.S. Government has issued numerous policies aimed at reducing federal facility energy consumption; the most recent, Executive Order 13514, requires that new construction designed after 2020 can achieve net-zero energy by 2030. The policy defines a Zero-Energy Building as one that is designed, constructed, and operated to reduce energy demand to a level which can be offset from sources of renewable energy. This research develops and evaluates a feasibility assessment model based on life-cycle cost. It incorporates geospatial analysis to calculate and summarize input values for all Air Force installations in the Contiguous U.S. A comparative analysis is then …


An Analysis Of Cost Premiums And Losses Associated With Usaf Military Construction (Milcon), Daniel L. Blomberg Mar 2013

An Analysis Of Cost Premiums And Losses Associated With Usaf Military Construction (Milcon), Daniel L. Blomberg

Theses and Dissertations

Military construction (MILCON) represents 40% of the federal government's $30 billion construction budget. The federal budget is fixed; therefore, any cost overages likely affect project scope or requirements. This study investigated if MILCON procurement costs more than private industry construction and if so, what causes the cost premiums. A combination of in-depth literature review, expert interviews, a unique case study, expert surveys, and geospatial statistical analysis answered the research question. The case study evaluated two nearly identical projects to determine how internal factors affect MILCON cost premiums. This study confirmed the existence of MILCON cost premiums. Additionally, 11 major cost …


Influence Of Media Size And Flow Rate On The Transport Of Silver Nanoparticles In Saturated Porous Media: Laboratory Experiments And Modeling, Travis J. Meidinger Mar 2013

Influence Of Media Size And Flow Rate On The Transport Of Silver Nanoparticles In Saturated Porous Media: Laboratory Experiments And Modeling, Travis J. Meidinger

Theses and Dissertations

Silver nanoparticles (AgNPs) are widely produced and used. Because of their potential toxicity and the possibility of their release into the environment, it is important to understand the factors involved in their transport; particularly how they may move in groundwater, which is a potential pathway to human and environmental receptors. By passing a solution of 15 mg/L AgNPs with an average size of 17 nm through sand-filled glass columns, this study looks at the physical effects of flow rate and media size on transport. Three different sand sizes ( 0.074, 0.21-0.297, and 0.4-2.0mm) were used, as well as two different …


Biodegradation Of An Organophosphate Chemical Warfare Agent Simulant By Activated Sludge With Varying Solid Retention Times, Allen K. Janeczko Mar 2013

Biodegradation Of An Organophosphate Chemical Warfare Agent Simulant By Activated Sludge With Varying Solid Retention Times, Allen K. Janeczko

Theses and Dissertations

This study examined the fate of malathion, a surrogate compound for VX studies, in bench-scale sequencing batch bioreactors being operated under varied solid retention times (SRTs) to simulate the activated sludge process in wastewater treatment facilities. Results show that a constant influent of the malathion will largely be removed. However, the heterotrophic bacteria undergo a stress response which temporarily inhibits malathion removal, the extent of which increases with increasing SRTs. After this stress response takes place, the activated sludge is able to resume a high degree of malathion removal, even with increased influent concentration; however, this is done so at …


Case Study Analysis Of Trust And Commitment Between The Civil Engineering Commodity Council And The Civil Engineering Career Field, Jonnathan B. Page Mar 2013

Case Study Analysis Of Trust And Commitment Between The Civil Engineering Commodity Council And The Civil Engineering Career Field, Jonnathan B. Page

Theses and Dissertations

The Air Force is pursuing strategic sourcing as a strategy for reducing costs of goods and services to help meet budget reductions while still performing its mission. These commodities are sourced through a number of commodity councils, each of which whom interact with their stakeholders throughout the sourcing process for that specific commodity. This research identifies factors that influence the success or failure of the sourcing process from the perspective of the Civil Engineering Commodity Council (CECC) and attempts to organize these factors within a framework built around trust and its effect on commitment and cooperation. These factors were identified …


Fate Of Malathion In An Activated Sludge Municipal Wastewater Treatment System, Edward B. Walters Mar 2013

Fate Of Malathion In An Activated Sludge Municipal Wastewater Treatment System, Edward B. Walters

Theses and Dissertations

Organophosphate compounds are used as pesticides and in chemical warfare agents such as nerve agents. VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate) is one of the most toxic and environmentally persistent of these nerve agents. This research examined the fate of malathion, a pesticide and surrogate of VX (O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate), in bench-scale activated sludge (AS) sequencing batch reactors. Sorption kinetics and sorption equilibrium isotherm experiments indicate that sorption to AS biomass was not a statistically important removal mechanism. However, approximately 90% of the initial 4.25 mg L-1 malathion concentration degraded primarily via heterotrophic activity.


Understanding The Effects Of Climate On Airfield Pavement Deterioration Rates, Justin C. Meihaus Mar 2013

Understanding The Effects Of Climate On Airfield Pavement Deterioration Rates, Justin C. Meihaus

Theses and Dissertations

Over the past two decades, pavement engineers at the Air Force Civil Engineer Center have noticed the majority of identified distresses from PCI airfield surveys are climate related. To verify these trends, a comprehensive analysis of the current airfield pavement distress database was accomplished based on a climate region perspective. A four-zone regional climatic model was created for the United States using geospatial interpolation techniques and climate data acquired from WeatherBank Inc. Once the climatic regional model was developed, the climate information for each installation was imported into the Air Force pavement distress database within PAVER. Utilizing the pavement condition …


Assessment Of Potential Carbon Dioxide-Based Demand Control Ventilation System Performance In Single Zone Systems, Joseph G. Pickenpaugh Mar 2013

Assessment Of Potential Carbon Dioxide-Based Demand Control Ventilation System Performance In Single Zone Systems, Joseph G. Pickenpaugh

Theses and Dissertations

Heating, ventilation, and air conditioning (HVAC) use accounts for 43% of commercial energy consumption, with close to 5% used for ventilation purposes. Federal government agencies face both energy consumption reduction mandates and reduced funding. Carbon dioxide (CO2) based demand control ventilation (DCV) is a technology that allows for reduced energy consumption by allowing facility designers to introduce outside air based on facility occupancy, per American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) standards. This research aims to create a generalized methodology assessing energy and cost reductions from CO2-based DCV and then apply it to a specific facility at …


A Trophic State Analysis Of Lakes In Yellowstone National Park, Anthony Alexander Melcher Mar 2013

A Trophic State Analysis Of Lakes In Yellowstone National Park, Anthony Alexander Melcher

Theses and Dissertations

Eutrophication is of interest in the field of water quality. Eutrophic lakes, when used as sources for drinking water, can cause problems during the treatment process, for example algae blooms can clog filters, requiring more water and energy to be used during the cleaning and backwashing of the filters. Excess nutrient loading and eutrophication can also harm fish and aquatic life habitats. Certain species of algae and cyanobacteria can be toxic to humans as well. Since 1998, Dr. A. Woodruff Miller has collected water samples from 46 lakes and ponds in Yellowstone National Park. The Carlson Trophic State Index, the …


Passive Force On Skewed Abutments With Mechanically Stabilized Earth (Mse) Wingwalls Based On Large-Scale Tests, Bryan William Franke Mar 2013

Passive Force On Skewed Abutments With Mechanically Stabilized Earth (Mse) Wingwalls Based On Large-Scale Tests, Bryan William Franke

Theses and Dissertations

Passive force-deflection behavior for densely compacted backfills must be considered in bridge design to ensure adequate resistance to both seismic and thermally induced forces. Current codes and practices do not distinguish between skewed and non-skewed bridge abutment geometries; however, in recent years, numerical models and small-scale, plane-strain laboratory tests have suggested a significant reduction in passive force for skewed bridge abutments. Also, various case studies have suggested higher soil stresses might be experienced on the acute side of the skew angle. For these reasons, three large-scale tests were performed with abutment skew angles of 0, 15 and 30 degrees using …


Lateral Resistance Of Piles Near Vertical Mse Abutment Walls At Provo Center Street, Kent R. Nelson Mar 2013

Lateral Resistance Of Piles Near Vertical Mse Abutment Walls At Provo Center Street, Kent R. Nelson

Theses and Dissertations

Full scale lateral load tests were performed on four piles located at various distances behind MSE walls. Three of the four test piles were production piles used to support bridges, and the other pile a production pile used as part of the bridge abutment. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force resisted by the MSE reinforcement. Lateral load-displacement curves were developed for pile at various spacing and with various reinforcement ratio (reinforcement length, L divided by wall height, H). The force …


Evaluation Of Passive Force On Skewed Bridge Abutments With Large-Scale Tests, Aaron Kirt Marsh Mar 2013

Evaluation Of Passive Force On Skewed Bridge Abutments With Large-Scale Tests, Aaron Kirt Marsh

Theses and Dissertations

Accounting for seismic forces and thermal expansion in bridge design requires an accurate passive force versus backwall deflection relationship. Current design codes make no allowances for skew effects on the development of the passive force. However, small-scale experimental results and available numerical models indicate that there is a significant reduction in peak passive force as skew angle increases for plane-strain cases. To further explore this issue large-scale field tests were conducted at skew angles of 0°, 15°, and 30° with unconfined backfill geometry. The abutment backwall was 11 feet (3.35-m) wide by 5.5 feet (1.68-m) high, and backfill material consisted …


Starch Resin Moisture Level Effect On Injection Molding Processability And Molded Part Mechanical Properties With Pure Starch Resin And Polymer Blends, Jordan M. Ellingson Mar 2013

Starch Resin Moisture Level Effect On Injection Molding Processability And Molded Part Mechanical Properties With Pure Starch Resin And Polymer Blends, Jordan M. Ellingson

Theses and Dissertations

The current and forecasted global consumption of plastic packaging and products through the 21st century combined with the already reported and growing negative impact of plastics on the environment due to plastics being synthesized from nonrenewable resources that do not biodegrade is of serious concern. However, recent advances in starch technology including the development of thermoplastic starch (TPS) materials —polymers that are both renewable and biodegradable—have brought hope to reducing this impact. The mechanical properties of thermoplastic starch have often been improved by blending with synthetic polymers. One issue that arises with blending is volatilization of the melt from moisture …


Location-Allocation Optimization Of Supply Chain Distribution Networks: A Case Study, Mark Nicholas Helberg Mar 2013

Location-Allocation Optimization Of Supply Chain Distribution Networks: A Case Study, Mark Nicholas Helberg

Theses and Dissertations

The location of distribution centers is an important strategic decision in supply chain design, particularly as it relates to service quality, productivity, and profitability of the firm. There has been extensive research performed on distribution location models which require the use of complex algorithms and assumptions that make use of these models difficult in practice for small and medium enterprises (SMEs) that have limited capital and resources. Studies have also failed to capture and quantify potential business results of using more sophisticated methods. In this study, a deterministic and static location-allocation model is designed using a prototype software tool. The …


Influence Of Moving Load, Structure, Temperature Gradient, And Wheel Configuration On Load Transfer Efficiency, Akshay Joshi Mar 2013

Influence Of Moving Load, Structure, Temperature Gradient, And Wheel Configuration On Load Transfer Efficiency, Akshay Joshi

Theses and Dissertations

An airport pavement consists of one or more paving materials over the natural subgrade. Pavement design involves the interaction of pavement with vehicular loads and climatic conditions. The Federal Aviation Administration (FAA) uses a mechanistic design procedure, FAARFIELD, for the design of rigid airport pavements. The FAARFIELD (FAA Rigid and Flexible Iterative Elastic Layer Design) procedure is based on layered elastic and three-dimensional finite element-based structural analysis developed to calculate design thicknesses for airfield pavements. The design procedure assumes constant stress-based load transfer efficiency (LTE (S)), of 25% at the joints. Variations in environmental conditions, loading characteristics, type of joint …