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Civil and Environmental Engineering Faculty Publications

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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 …

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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 …

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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 …

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Serviceability-Based Dynamic Loan Rating Of A Lt20 Bridge, P. Siswobusono, S.-E. Chen, S. Jones, D. Callahan, T. Grimes, Norbert Delatte Nov 2004

Serviceability-Based Dynamic Loan Rating Of A Lt20 Bridge, P. Siswobusono, S.-E. Chen, S. Jones, D. Callahan, T. Grimes, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

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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 …

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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 …

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Effect Of Supplementary Cementitious Materials On The Compressive Strength And Durability Of Short-Term Cured Concrete, H. Toutanji, Norbert Delatte, S. Aggoun, R. Duval, A. Danson Feb 2004

Effect Of Supplementary Cementitious Materials On The Compressive Strength And Durability Of Short-Term Cured Concrete, H. Toutanji, Norbert Delatte, S. Aggoun, R. Duval, A. Danson

Civil and Environmental Engineering Faculty Publications

This research focuses on studying the effect different supplementary cementitious materials (silica fume, fly ash, slag, and their combinations) on strength and durability of concrete cured for a short period of time—14 days. This work primarily deals with the characteristics of these materials, including strength, durability, and resistance to wet and dry and freeze and thaw environments. Over 16 mixes were made and compared to the control mix. Each of these mixes was either differing in the percentages of the additives or was combinations of two or more additives. All specimens were moist cured for 14 days before testing or …

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Collapse Of 2000 Commonwealth Avenue: Punching Shear Case Study, Suzanne King, Norbert Delatte Feb 2004

Collapse Of 2000 Commonwealth Avenue: Punching Shear Case Study, Suzanne King, Norbert Delatte

Civil and Environmental Engineering Faculty Publications

On January 25, 1971, two thirds of a 16-story apartment building collapsed while under construction at 2000 Commonwealth Avenue, Boston, Massachusetts. Four workers died after a failure on the roof instigated a progressive collapse all the way to the basement, where the men were found. Fortunately, the collapse occurred slowly enough for most of the other workers to run to safety. An investigation, conducted by a commission assembled by the Mayor of Boston, painted a picture of a troubled project, with considerable confusion about responsibility for structural safety. The surviving workers’ descriptions of the failure provide a textbook definition of …

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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 …

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Undergraduate Summer Research In Structural Engineering, Norbert J. Delatte Jan 2004

Undergraduate Summer Research In Structural Engineering, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

For the last seven years, a summer Research Experiences for Undergraduates site in structural engineering, funded by the National Science Foundation, has operated at the University of Alabama at Birmingham. During this time, 33 students from 22 colleges and universities have participated in the site. Participants are recruited nationally and have come from as far away as California and Puerto Rico. The program is intended to provide students interested in graduate studies with an introduction to research methods, and to provide students who will not continue their studies past a bachelor of science in civil engineering with a better understanding …

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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 …

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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.

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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 …

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C-Ring Strength Of Advanced Monolithic Ceramics, A. A. Wereszczak, R. J. Caspe, J. J. Swab, S. F. Duffy, E. H. Baker Dec 2003

C-Ring Strength Of Advanced Monolithic Ceramics, A. A. Wereszczak, R. J. Caspe, J. J. Swab, S. F. Duffy, E. H. Baker

Civil and Environmental Engineering Faculty Publications

Alumina, silicon carbide, silicon nitride, and zirconia are common candidate ceramics for load-bearing tubular components. To help facilitate design and reliability modeling with each ceramic, Weibull strength distributions were determined with each material using a diametrally compressed c-ring specimen in accordance with ASTM C1323. The investigated silicon nitride and zirconia were found to exhibit higher uncensored characteristic strengths than the alumina and silicon carbide. The occurrence of chamfer-located fracture initiation was problematic, and hindered the ability to generate valid design data in some of these ceramics. Fractography and stress modeling results suggest that some aspects of ASTM C1323 should be …

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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 …

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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 …

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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 …

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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 …

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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.

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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 …

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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), …

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Using The Ltpp Database In A Pavement Design Course, Norbert J. Delatte Oct 2002

Using The Ltpp Database In A Pavement Design Course, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

The Strategic Highway Research Program Long Term Pavement Performance (LTPP) database provides considerable information about a large number of pavement test sections. The information may be easily accessed using DataPave 2.0 software, available free from the Federal Highway Administration. This software provides information on approximately 3,000 sections, with several modules for data analysis and extraction. This paper describes the integration of LTPP DataPave 2.0 software into a pavement design course. The database was used at several points throughout the course, including lessons on traffic characterization, materials, reliability, performance, and design. Twelve Texas pavement case studies were used. Each student was …

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Forensics And Case Studies In Civil Engineering Education: State Of The Art, Norbert J. Delatte, Kevin L. Rens Aug 2002

Forensics And Case Studies In Civil Engineering Education: State Of The Art, Norbert J. Delatte, Kevin L. Rens

Civil and Environmental Engineering Faculty Publications

This paper reviews the state of the art in the use of forensic engineering and failure case studies in civil engineering education. The study of engineering failures can offer students valuable insights into associated technical, ethical, and professional issues. Lessons learned from failures have substantially affected civil engineering practice. For the student, study of these cases can help place design and analysis procedures into historical context and reinforce the necessity of lifelong learning. Three approaches for bringing forensics and failure case studies into the civil engineering curriculum are discussed in this paper. These are stand-alone forensic engineering or failure case …

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Agricultural Product Loads And Warehouse Failures, Norbert J. Delatte Aug 2002

Agricultural Product Loads And Warehouse Failures, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Two manufactured metal building warehouses loaded with agricultural products failed in service. Inspection revealed considerable damage to the structure and the foundation. The building owner filed suit against the building supplier, the building erector, and the soils testing laboratory whose engineer had designed the foundation. The agricultural product imposed substantial outward lateral pressures on the walls of the structures. Review of the available design documents indicated that these loads had not been accounted for in design. A structural analysis revealed that elements of the structure were underdesigned for the agricultural product loads. In addition, the foundation did not have any …

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Closure To “Another Look At The L’Ambiance Plaza Collapse,” By Rachel Martin And Norbert J. Delatte, Norbert J. Delatte Feb 2002

Closure To “Another Look At The L’Ambiance Plaza Collapse,” By Rachel Martin And Norbert J. Delatte, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

No abstract provided.

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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 …

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Lessons From Roman Cement And Concrete, Norbert J. Delatte Jul 2001

Lessons From Roman Cement And Concrete, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Although masonry and lime mortars had been used for centuries by earlier civilizations, the Romans were the first to extensively use naturally occurring volcanic earth to make hydraulic cement. The volcanic powder named “pulvis puteolanis,” found near the town of Puteoli near Naples (now Pozzouli), was used to build magnificent structures. The use of this hydraulic cement in masonry and concrete greatly expanded civil engineering possibilities. The Roman engineer Vitruvius, writing in The Ten Books on Architecture, described the careful materials selection, proportioning, and workmanship that was critical to the performance of Roman concrete. Masonry and coarse and fine …

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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.

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Another Look At Hartford Civic Center Coliseum Collapse, Rachel Martin, Norbert J. Delatte Feb 2001

Another Look At Hartford Civic Center Coliseum Collapse, Rachel Martin, Norbert J. Delatte

Civil and Environmental Engineering Faculty Publications

Only a few hours after five thousand basketball fans had left, the roof of the Hartford Civic Center Coliseum collapsed under a heavy snowfall. Fortunately, the arena was empty. The design of the space frame roof had been based on an innovative and extensive computer analysis. However, when deflections twice as great as those predicted by the computer analysis were observed during construction, the warning was ignored. Overconfidence in computer analysis results played a large part in this failure. A useful lesson from this case is that the computer is only an analytical tool and computed results must be checked …

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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 …

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