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Articles 1231 - 1260 of 2083

Full-Text Articles in Civil and Environmental Engineering

Reply To Comment By Jonathan J. Rhodes On ‘‘Modeling Of The Interactions Between Forest Vegetation, Disturbances, And Sediment Yields’’, Charles H. Luce, David G. Tarboton, Erkan Istanbulluoglu, Robert T. Pack Feb 2005

Reply To Comment By Jonathan J. Rhodes On ‘‘Modeling Of The Interactions Between Forest Vegetation, Disturbances, And Sediment Yields’’, Charles H. Luce, David G. Tarboton, Erkan Istanbulluoglu, Robert T. Pack

Civil and Environmental Engineering Faculty Publications

Rhodes [2005] brings up some excellent points in his comments on the work of Istanbulluoglu et al. [2004]. We appreciate the opportunity to respond because it is likely that other readers will also wonder how they can apply the relatively simple analysis to important policy questions. Models necessarily reduce the complexity of the problem to make it tractable and synthesize some diverse sources of information. It may be helpful at times for readers to understand the high dimension of the complexity sacrificed in order to obtain the synthesis and the reasons for reducing the complexity in a particular manner. Rhodes …


Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta Jan 2005

Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Best utilizing water resources requires coordinating their availability and use in time and space. Required can be: spatially and temporally distributed data; simulators to predict system response to stimuli; procedures for defining management goals, constraints, and scenarios; optimizers to compute optimal management strategies; and appropriate strategy implementation techniques. Here, a strategy is a set of controllable groundwater extraction and injection rates and surface water diversions. Simulation/optimization (S/O) models couple simulators and optimizers to compute optimal strategies for posed management problems. S/O models are becoming more commonly used for policy, planning, system design, and management. For example, water planners and managers …


Developed Pumping Strategies For Mather Afb Tce Plume, Richard C. Peralta, Bassel Timani Nov 2004

Developed Pumping Strategies For Mather Afb Tce Plume, Richard C. Peralta, Bassel Timani

Civil and Environmental Engineering Faculty Publications

Accomplishments prior to BCT Meeting/Phone Conference of 14 October 2004 Prior to 14 October 2004, the best pumping strategy USU achieved manually completely contains both PCE and TCE1 (within revised containment zones proposed by USU on that date), at the end of years 2, 3, 4, 5 and 5-year intervals thereafter. This strategy uses two new extraction wells (USUE3 and USUE4). The strategy did not utilize a recently constructed well EW-12B. USU did not previously know about EW-12B and the well package USU received did not indicate a well at its location, cell (3,58,43). On 14 October, USU also learned …


Optimización Para El Normado, Planeamiento, Diseño Y Manejo Del Agua Subterránea, Richard C. Peralta Oct 2004

Optimización Para El Normado, Planeamiento, Diseño Y Manejo Del Agua Subterránea, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Los modelos de Simulación/optimización (S/O) junta modelos de simulación y optimización para calcular estrategias óptimas para el manejo del agua subterránea ante problemas de optimización propuestos. Una estrategia es un conjunto de caudales de extracción e inyección de agua subterráneas distribuidas espacial y temporalmente. Los modelos S/O están llegando a ser más comúnmente usados para el desarrollo de normas, planeamiento, diseño del sistema y manejo. Por ejemplo, los encargados del manejo y planificación del agua algunas veces deben decidir como controlar el uso del agua subterránea para originar un futuro favorable y evitar serios problemas. Los modelos S/O pueden ayudar …


Hydraulic Characteristics Of Labyrinth Weirs, Corwin M. Willmore May 2004

Hydraulic Characteristics Of Labyrinth Weirs, Corwin M. Willmore

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Primarily, half-round crest labyrinth weirs were tested in this study with the side leg angle (a) ranging between 7 to 35 degrees. Historical data was primarily limited to quarter-round data. This study presents data and equations for estimating the discharge coefficient for labyrinth weirs with both half-round, quarter-round, and two Ogee-type crest weir shapes . A method is presented for comparing the flow capacity between weirs in order to determine the most efficient weir at a given Ht/P. For a labyrinth weir with the crest shape,# of cycles (N), and the cycle width (w) held constant, the discharge coefficient (Cct) …


Interim Sediment Management Plan For First Dam, Logan River, Thirumurugan Bose May 2004

Interim Sediment Management Plan For First Dam, Logan River, Thirumurugan Bose

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Sediment is a serious problem in the management of dams all over the world. In this project an interim sediment management plan for First Dam, on the Logan River in northern Utah, is discussed. The objective of the plan is to control the sediment budget of the reservoir in such a way that other reservoir maintenance activities (e.g., unusual draw downs for structural repairs) will produce minimal downstream environmental impacts on water quality and aquatic resources.

This report presents a detailed literature review of the various sediment management practices used for reservoir sediment control. It also discusses the downstream effects …


Analytical And Numerical Investigation Of A Mechanically Stabilized Earth Wall On I-15, Aaron S. Budge May 2004

Analytical And Numerical Investigation Of A Mechanically Stabilized Earth Wall On I-15, Aaron S. Budge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation is the culmination of extensive research into the behavior of a mechanically stabilized earth (MSE) wall at I-15 and 3600 South in Salt Lake City, Utah. The wall is about 30 ft tall and is constructed on a compressible, soft clay foundation. Research on this project has included extensive instrumentation and monitoring of stresses and deformations in the wall and its foundation, a study of the effects of drilling and sampling method on disturbance of samples, and extensive laboratory testing to determine strength and deformation properties of soils at the site. The results of these portions of the …


Shear Wave Velocity Profiling Of Poorly Characterized Geologic Units In Salt Lake Valley, Utah, Jeff W. Gilbert May 2004

Shear Wave Velocity Profiling Of Poorly Characterized Geologic Units In Salt Lake Valley, Utah, Jeff W. Gilbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Shear wave velocity profiling in poorly characterized geologic units was successfully completed at 44 sites in and around the Salt Lake City metropolitan area by a team from Utah State University, Utah Geological Survey, and University of Utah Seismograph Stations. The sites tested in the Salt Lake Valley have been used to redefine site response geologic units Q02, Q03, and Q04 within the valley, and refocus future research in geologic units along the Wasatch Front.

This testing was carried out using the USU mobile source trailer and combining the results of Spectral Analysis of Surface Waves and refraction testing. Results …


Modeling Of The Interactions Between Forest Vegetation, Disturbances, And Sediment Yields, Erkan Istanbulluoglu, David G. Tarboton, Robert T. Pack, Charles H. Luce Feb 2004

Modeling Of The Interactions Between Forest Vegetation, Disturbances, And Sediment Yields, Erkan Istanbulluoglu, David G. Tarboton, Robert T. Pack, Charles H. Luce

Civil and Environmental Engineering Faculty Publications

The controls of forest vegetation, wildfires, and harvest vegetation disturbances on the frequency and magnitude of sediment delivery from a small watershed (∼3.9 km2) in the Idaho batholith are investigated through numerical modeling. The model simulates soil development based on continuous bedrock weathering and the divergence of diffusive sediment transport on hillslopes. Soil removal is due to episodic gully erosion, shallow landsliding, and debris flow generation. In the model, forest vegetation provides root cohesion and surface resistance to channel initiation. Forest fires and harvests reduce the vegetation. Vegetation loss leaves the land susceptible to erosion and landsliding until the vegetation …


Implications Of On-Ground Nitrogen Loading And Soil Transformations On Ground Water Quality Management, M. Almasri, Jagath J. Kaluarachchi Feb 2004

Implications Of On-Ground Nitrogen Loading And Soil Transformations On Ground Water Quality Management, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

This paper presents a modeling approach based on a geographic information system (GIS) to estimate the variability of on-ground nitrogen loading and the corresponding nitrate leaching to ground water. The methodology integrates all point and nonpoint sources of nitrogen, the national land cover database, soil nitrogen transformations, and the uncertainty of key soil and land use-related parameters to predict the nitrate mass leaching to ground water. The analysis considered 21 different land use classes with information derived from nitrogen sources such as fertilizer and dairy manure applications, dairy lagoons, septic systems, and dry and wet depositions. Simulations were performed at …


Cee6880 - Soil-Based Hazardous Waste Management, Spring 2004, Ron Sims Jan 2004

Cee6880 - Soil-Based Hazardous Waste Management, Spring 2004, Ron Sims

Civil and Environmental Engineering - OCW

Engineering management of hazardous wastes present in the vadose zone, including extraction, containment, and biological, chemical, and physical destruction technologies. Aspects include engineering characterization, problem definition, treatment, and monitoring. Analysis and design emphasized through problems, examinations, and report writing.

Technical Requirements: A PC is required to run the Fugacity Calculator.


Software For Optimizing International Water Resources Management, Richard C. Peralta, S. Wu Jan 2004

Software For Optimizing International Water Resources Management, Richard C. Peralta, S. Wu

Civil and Environmental Engineering Faculty Publications

The Simulation/Optimization MOdeling System (SOMOS) has modules adapted for a range of international water resource management needs. The SOMOA module is best for field groundwater and conjunctive water management situations. It employs several analytical simulation models and several optimization methods to give appropriate optimal guidance for situations having sparse data. SOMOA requires understanding of the limitations of common analytical equations. It does not require experience in finite difference or element numerical modeling. SOMOS also has modules ideal for situations in which there is sufficient data for numerical modeling or aquifer and stream-aquifer systems. Emphasized here are SOMOA and its applications …


Multi-Objective Conjunctive Use Optimization, H. C. Fayad, Richard C. Peralta Jan 2004

Multi-Objective Conjunctive Use Optimization, H. C. Fayad, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

This paper presents a simulation/optimization model based on artificial neural networks and genetic algorithms for solving multi-objective conjunctive water use problems. The model simulates and optimizes water flows in a hydraulically connected reservoir-stream-aquifer system. It is a powerful tool to help water managers and authorities in developing conjunctive water management strategies and evaluating tradeoffs between conflicting goals.


Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad Jan 2004

Optimization Modeling For Groundwater And Conjunctive Use Water Policy Development, Richard C. Peralta, R. Shulstad

Civil and Environmental Engineering Faculty Publications

Planners must sometimes decide how to restrict or reduce groundwater use to prevent unacceptable future problems. Often there are several alternatives (policies). Comparing policies can involve formulating a sustained groundwater yield optimization problem and computing an optimal groundwater pumping strategy for each. This is easy via the SOMOS simulation/optimization (S/O) model. Subsequent analysis can include: flow simulation to predict transient water level response to pumping; and economic evaluation to estimate costs and returns. Two examples predict the best consequences of potential physical and legal management policies for alluvial and valley basin fill aquifers hydraulically linked to surface waters. Results show …


Multi-Criteria Decision Analysis With Probabilistic Risk Assessment For The Management Of Contaminated Ground Water, I. Khadam, Jagath J. Kaluarachchi Oct 2003

Multi-Criteria Decision Analysis With Probabilistic Risk Assessment For The Management Of Contaminated Ground Water, I. Khadam, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Traditionally, environmental decision analysis in subsurface contamination scenarios is performed using cost–benefit analysis. In this paper, we discuss some of the limitations associated with cost–benefit analysis, especially its definition of risk, its definition of cost of risk, and its poor ability to communicate risk-related information. This paper presents an integrated approach for management of contaminated ground water resources using health risk assessment and economic analysis through a multi-criteria decision analysis framework. The methodology introduces several important concepts and definitions in decision analysis related to subsurface contamination. These are the trade-off between population risk and individual risk, the trade-off between the …


Modeling And Control Of Vinyl Chloride In Drinking Water Distribution Systems, M Beardsley, Craig D. Adams Sep 2003

Modeling And Control Of Vinyl Chloride In Drinking Water Distribution Systems, M Beardsley, Craig D. Adams

Civil and Environmental Engineering Faculty Publications

In water distribution systems containing PVC pipe manufactured in the “early era” (prior to 1977), vinyl chloride can leach into drinking water resulting in vinyl chloride concentrations exceeding the 2 μg⋅L−1 maximum contaminant level. Field testing of dead-end segments of water distribution systems consisting of early-era PVC pipe was conducted to examine their initial intrapipe vinyl chloride monomer (VCM) concentrations based on a Fickian-diffusion-based leaching model. The experiments showed a wide range of VCM concentrations within early-era PVC pipe ranging from less than 50 to more than 600 mg⋅kg−1. Based on the diffusion modeling approach, a protocol was designed that …


Applicability Of Risk-Based Management And The Need For Risk-Based Economic Decision Analysis At Hazardous Waste Contaminated Sites, I. Khadam, Jagath J. Kaluarachchi Jul 2003

Applicability Of Risk-Based Management And The Need For Risk-Based Economic Decision Analysis At Hazardous Waste Contaminated Sites, I. Khadam, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Decision analysis in subsurface contamination management is generally carried out through a traditional engineering economic viewpoint. However, new advances in human health risk assessment, namely, the probabilistic risk assessment, and the growing awareness of the importance of soft data in the decision-making process, require decision analysis methodologies that are capable of accommodating non-technical and politically biased qualitative information. In this work, we discuss the major limitations of the currently practiced decision analysis framework, which evolves around the definition of risk and cost of risk, and its poor ability to communicate risk-related information. A demonstration using a numerical example was conducted …


A Sediment Transport Model For Incising Gullies On Steep Topography, Erkan Istanbulluoglu, David G. Tarboton, Robert T. Pack, Charles H. Luce Apr 2003

A Sediment Transport Model For Incising Gullies On Steep Topography, Erkan Istanbulluoglu, David G. Tarboton, Robert T. Pack, Charles H. Luce

Civil and Environmental Engineering Faculty Publications

We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates are assumed to provide an estimate of sediment transport capacity at each survey cross section from the single gully-forming thunderstorm. Sediment transport models commonly relate transport capacity to overland flow shear stress, which is related to runoff rate, slope, and drainage area. We have estimated the runoff rate and duration associated with the gully-forming …


Water Management: Partnerships For Future Directions (Research And Testing Education Support Outreach), Mac Mckee Jan 2003

Water Management: Partnerships For Future Directions (Research And Testing Education Support Outreach), Mac Mckee

Reports

The UWRL is uniquely positioned to form collaborations with USU departments, other academic institutions and water centers, government, and private sector organizations involved in addressing water issues. The strong and consistent support of the State of Utah illustrates the importance of water and the creation of knowledge to manage water in Utah and the surrounding western states. The scope of projects ranges from multimillion dollar partnerships related to soil and groundwater remediation with national impacts, to small scale projects related to outreach to a specific city or county public sector audience. The UWRL mission, the strategy used to accomplish the …


Somos Simulation/Optimization Modeling System, Richard C. Peralta Jan 2003

Somos Simulation/Optimization Modeling System, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

SOMOS (Simulation / Optimization Modeling System) is a family of simulation / optimization (S/O) modules to aid in optimally managing water resources. SOMOS results from twenty years experience developing optimization models and applying them to real-world problems, including 11 pump-and-treat (PAT) systems and numerous water supply problems. SOMOS significantly improves water management or designs and saves money. Its user’s manual provides excellent training in principles of applying optimization to managing aquifer and stream-aquifer systems. It is being incorporated with powerful groundwater modeling and visualization packages.


Practical Simulation /Optimization Modeling For Groundwater Quality And Quantity Management, Richard C. Peralta, Ineke M. Kalwij, Shengjun Wu Jan 2003

Practical Simulation /Optimization Modeling For Groundwater Quality And Quantity Management, Richard C. Peralta, Ineke M. Kalwij, Shengjun Wu

Civil and Environmental Engineering Faculty Publications

Software for mathematically optimizing groundwater management has improved significantly in recent years. The SOMOS code can readily handle large complex plume and water management problems. Most recently, it developed a least-cost $40.82M 30-yr pumping strategy for the 6.58 mile long Blaine NAD plume. That strategy was 19 percent better than the strategy developed simultaneously by an experienced consultant using normal trial and error simulation procedures. The management problem involved 60 stress periods, and well installation and pumping rates that could change every 10 periods. The optimal strategy employed 10 new wells. At a simpler site, SOMOS helped select robust strategies …


Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta Dec 2002

Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present optimal pumping strategies to address RDX and TNT plumes at Umatilla Chemical Depot (UCD). We provide strategies for four optimization problem formulations. Each strategy requires constructing 2 wells. New Well U-1 is in the same location for all strategies. The second well location can differ with formulation. The number in a strategy’s name refers to the formulation it addresses. Using optimization in design is normally an iterative process involving interaction between the designer and client after preliminary optimizations are performed. This project does not permit that. To compensate, we present a second strategy for Formulation 1 (Strategy USU1B), …


Finite Element And Pullout Test Performance Of Welded Wire Mats, Bradley C. Conder May 2002

Finite Element And Pullout Test Performance Of Welded Wire Mats, Bradley C. Conder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper reports on the pullout test performance of welded-wire reinforcing mats. A 126-foot high mechanically stabilized earth wall was constructed at Kennecott Utah Copper. In the lower half of the wall, single lengths of 50-foot long welded-wire mats were used. In the top half of the wall, two lengths of 50-foot mats were overlapped 10 feet to create 90-foot mats. This 10-foot "lap zone" was investigated in this study.

The finite element program Plaxis was used to investigate several pullout test parameters: overburden pressure, gap width, boundary effects, and horizontal spacing of transverse elements from the pullout box face. …


Is There Synchronicity In Nitrogen Input And Output At The Noland Divide Watershed, A Small N-Saturated Forested Catchment In The Great Smoky Mountains National Park, H. Van Miegroet, I. F. Creed, N. S. Nicholas, David G. Tarboton, K. L. Webster, J. Schubzda, B. Robinson, J. Smoot, D. W. Johnson, S. E. Lindberg, G. Lovett, S. Nodvin, S. Moore Nov 2001

Is There Synchronicity In Nitrogen Input And Output At The Noland Divide Watershed, A Small N-Saturated Forested Catchment In The Great Smoky Mountains National Park, H. Van Miegroet, I. F. Creed, N. S. Nicholas, David G. Tarboton, K. L. Webster, J. Schubzda, B. Robinson, J. Smoot, D. W. Johnson, S. E. Lindberg, G. Lovett, S. Nodvin, S. Moore

Civil and Environmental Engineering Faculty Publications

High-elevation red spruce [Picea rubens Sarg.]-Fraser fir [Abies fraseri (Pursh.) Poir] forests in the Southern Appalachians currently receive large nitrogen (N) inputs via atmospheric deposition (30 kg N ha(-1) year(-1)) but have limited N retention capacity due to a combination of stand age, heavy fir mortality caused by exotic insect infestations, and numerous gaps caused by windfalls and ice storms. This study examined the magnitude and timing of the N fluxes into, through, and out of a small, first-order catchment in the Great Smoky Mountains National Park. It also examined the role of climatic conditions in causing interannual variations in …


Shear Wave Velocity Profiles At Sites Liquefied By The 1999 Kocaeli, Turkey Earthquake, Brady R. Cox May 2001

Shear Wave Velocity Profiles At Sites Liquefied By The 1999 Kocaeli, Turkey Earthquake, Brady R. Cox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents shear wave velocity profiles for 15 sites liquefied by the 1999 Kocaeli, Turkey earthquake. These profiles are used in order to evaluate each liquefaction site by the simplified shear wave velocity procedure. This procedure allowed for the identification of a potentially liquefiable region within the subsurface at each site. Locating this region at each site allowed for the separation of soils that were too stiff to liquefy from soils that were soft enough to liquefy. Once these soft regions had been identified, they were evaluated to separate granular soils expected to liquefy, from fine-grained soils expected not …


Terrain Analysis Using Digital Elevation Models, David G. Tarboton, Daniel Ames Apr 2001

Terrain Analysis Using Digital Elevation Models, David G. Tarboton, Daniel Ames

Civil and Environmental Engineering Faculty Publications

No abstract provided.


Development Of A Low-Cost, Self-Calibrating Stream Gaging Station, Gilberto Urroz, Robert C. Leines, Garryn L. Perret, Jared M. Holland, Brian E. Hunsaker Jan 2001

Development Of A Low-Cost, Self-Calibrating Stream Gaging Station, Gilberto Urroz, Robert C. Leines, Garryn L. Perret, Jared M. Holland, Brian E. Hunsaker

Reports

Executive Summary: The present report presents a review of the state-of-the-art technologies for the development of a low-cost, self-calibrating stream gaging station. The research was conducted by the Utah Water Research Laboratory with funding provided by the Utah Division of Water Resources through Project RP 110080, March 1998. The report presents a review of the current practices in stream gaging and how technologies such as remote data telemetry through the use of satellite, cellular phone communications, and radio telemetry can be used for the real-time transmission of data. The study also includes the use of Global Positioning System (GPS) for …


Remediation Simulation/Optimization Demonstrations, Richard C. Peralta Jan 2001

Remediation Simulation/Optimization Demonstrations, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Applications of simulation/optimization (S/0) software to develop contamination remediation strategies include formal remediation optimization using heads and gradients (hydraulics-based) and concentrations (risk-based) constraints. The six reported cases involve pump and treat systems, or pump, treat and re-inject systems, together termed PAT systems. We used S/0 modeling to perform hydraulic optimization for two of the sites and transport optimization for four. For four of the six sites, other parties used normal simulation (S) modeling alone to develop pumping strategies. Comparing the S/0 model-developed strategies with the S model-developed strategies showed S/0 modeling benefits ranging up to: (a) 25 percent reduction in …


Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta Jan 2001

Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Diverse water management simulation/optimization (S/O) experiences promoted the development of many S/O modeling approaches and models. Several of these are being incorporated within the Simulation/Optimization Modeling System (SOMOS). Non-modeler water scientists or engineers can apply one SOMOS module to optimize field-scale groundwater and conjunctive water management. Experienced groundwater modelers can apply other modules to optimally manage complex heterogeneous aquifer and stream-aquifer systems. SOMOS employs a variety of simulation models and approaches and optimization algorithms to optimize flow and contaminant management. SOMOS or its precursor modules have been well proven in real-world projects. Designed for use by consultants, students, academics, and …


Computing Optimal Pumping Strategies For Groundwater Contaminant Plume Remediation, Richard C. Peralta, Alaa H. Aly Sep 2000

Computing Optimal Pumping Strategies For Groundwater Contaminant Plume Remediation, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/Optimization (S/0) models can greatly simplify the process of designing remediation systems for contaminated groundwater. We describe some technical aspects of using S/0 models and possible S/0 model formulations for groundwater remediation design. We: discuss some S/0 model optimization algorithms; illustrate simple optimization problem solution; describe two real-world S/0 model applications; and demonstrate S/0 model application under uncertainty.