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2008

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Full-Text Articles in Civil and Environmental Engineering

Optimization Model For National Water Master Planning: Design And Documentation, Richard C. Peralta Apr 2008

Optimization Model For National Water Master Planning: Design And Documentation, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Physical distribution system and Balancing and Allocation and Transfer modules descriptors.


Numerical Analysis Of Passive Force On Skewed Bridgeabutments With Reinforced Concrete Wingwalls, Scott Karl Snow Apr 2008

Numerical Analysis Of Passive Force On Skewed Bridgeabutments With Reinforced Concrete Wingwalls, Scott Karl Snow

Theses and Dissertations

Numerical Analysis of Passive Force on Skewed BridgeAbutments with Reinforced Concrete WingwallsScott Karl SnowDepartment of Civil and Environmental Engineering, BYU Master of Science Historically bridges with skewed abutments have proven more likely to fail during earthquake loadings (Toro et al, 2013) when compared to non-skewed bridges (Apirakvorapinit et al. 2012; Elnashai et al. 2010). Previous studies including small-scale laboratory tests by Jessee (2012), large-scale field tests by Smith (2014), and numerical modeling by Shamsabadi et al. (2006) have shown that 45° skewed bridge abutments experience a reduction in peak passive force by about 65%. With numerous skewed bridges in the …


Impact Of Mass Mixing On The Lateral Resistance Of Driven-Pile Foundations, Mark Alan Herbst Mar 2008

Impact Of Mass Mixing On The Lateral Resistance Of Driven-Pile Foundations, Mark Alan Herbst

Theses and Dissertations

Although it has been established that in-situ soil mixing has improved the bearing capacity of soils, additional research is needed to better understand the effect of soil mixing on lateral resistance of pile caps. To do this, in-situ soil mixing was used to strengthen weak clay adjacent to a pile cap of a driven pile foundation. The mass stabilization method or mass mixing was used to treat an 11 ft wide, 4 ft thick, and 10 ft deep zone consisting of an average 475 psf clay that was adjacent to a 9-pile group in 3x3 pile configuration capped with a …


Development Of A Screening Tool To Facilitate Technology Of An Innovative Technology To Treat Perchlorate-Contaminated Water, Daniel A. Craig Mar 2008

Development Of A Screening Tool To Facilitate Technology Of An Innovative Technology To Treat Perchlorate-Contaminated Water, Daniel A. Craig

Theses and Dissertations

Perchlorate contamination of drinking water is a significant problem nationwide. The purpose of this study was to develop a tool to predict the cost and performance of tailored granular activated carbon (T-GAC), an innovative technology that is being evaluated as a cost-effective treatment for perchlorate-contaminated water. The ability to accurately predict performance and cost can facilitate the transfer and commercialization of innovative technologies. In the study, a model was developed to predict T-GAC performance and life-cycle costs for removing perchlorate under varying influent water quality and technology operating conditions. The model's design parameters were obtained from laboratory rapid small-scale column …


Selecting The Best Thermal Building Insulation Using A Multi-Attribute Decision Model, Theodore J. Sotoropolis Mar 2008

Selecting The Best Thermal Building Insulation Using A Multi-Attribute Decision Model, Theodore J. Sotoropolis

Theses and Dissertations

Thermal building insulation has traditionally been viewed as a means to reduce thermal conductivity through the building envelope. Builders typically choose the least expensive material which meets the specifications in order to remain competitive. Other factors regarding long term health and environmental consequences are typically dismissed. However, a recent shift toward sustainability requires that architects and engineers take a more responsible approach to building design. This research takes a holistic approach to selecting thermal building insulation through the use of a multi-attribute decision model. Several types of insulating products from a variety of manufacturers were investigated in order to determine …


Liquefaction Mitigation Using Vertical Composite Drains And Liquefaction Induced Downdrag On Piles: Implications For Deep Foundation Design, Spencer R. Strand Mar 2008

Liquefaction Mitigation Using Vertical Composite Drains And Liquefaction Induced Downdrag On Piles: Implications For Deep Foundation Design, Spencer R. Strand

Theses and Dissertations

Deep foundations constructed in liquefiable soils require specialized design. The design engineer of such foundations must consider the effects of liquefaction on the foundation and overlying structure, such as excessive settlement, loss of skin friction at the soil-pile interface, and the development of downdrag on the pile. Controlled blasting was employed to liquefy a loose, saturated sand in order to test the liquefaction prevention capabilities of full-scale, vertical composite earthquake (EQ) drains and to investigate the development of downdrag on full-scale test piles. Blasting produced liquefaction at a test site without EQ drains which eventually resulted in 270 mm of …


Automated Quadrilateral Coarsening By Ring Collapse, Mark William Dewey Mar 2008

Automated Quadrilateral Coarsening By Ring Collapse, Mark William Dewey

Theses and Dissertations

In most finite element analysis, a uniform mesh is not the optimum way to model the problem. Mesh adaptation is the ability to modify a finite element model to include regions of the mesh with higher and lower node density. Mesh adaptation has received extensive study in both computational mechanics and computer graphics to increase the resolution or accuracy of the solution in specific areas. The algorithm developed in this thesis, the Automated Quadrilateral Coarsening by Ring Collapse (AQCRC) algorithm, provides a unique solution to allow conformal coarsening of both structured and unstructured quadrilateral finite element meshes. The algorithm is …


Factors Leading To Effectiveness And Satisfaction In Civil Engineer Information Systems, Donald C. Crabtree Mar 2008

Factors Leading To Effectiveness And Satisfaction In Civil Engineer Information Systems, Donald C. Crabtree

Theses and Dissertations

The Air Force Civil Engineer Support Agency (AFCESA) has developed information systems in support of civil engineer operations. Over the last decade, the number of systems has grown to support the breadth of civil engineer functions. At this time, numerous (900+) decentralized systems support civil engineer functions around the world. Due to budget constraints, AFCESA is transforming civil engineer business processes to leverage the workforce in an optimized fashion. In support of this transition, AFCESA is posturing to acquire new information systems in support of civil engineer business processes. To help AFCESA improve upon its suite of information systems development …


Parallel Processing Of Reactive Transport Models Using Openmp, Jared D. Mclaughlin Mar 2008

Parallel Processing Of Reactive Transport Models Using Openmp, Jared D. Mclaughlin

Theses and Dissertations

Transport codes are beginning to be parallelized in order to allow more complex add-ons, such as geochemical packages, to utilize finer, more accurate grids, and to reduce solution times making stochastic and Monte Carlo simulations more feasible. Most codes parallelized via MPI (message passing interface) offer good results, but require the development of a new parallel code. OpenMP, the shared-memory standard, offers incremental parallelization, allowing sequential codes to remain relatively intact with minimal changes or additions. OpenMP allows speedup to be seen on personal computers with dual processors or greater, unlike some other parallelization approaches that require a supercomputer. An …


An Analysis Of Construction Cost And Schedule Performance, Michael J. Beach Mar 2008

An Analysis Of Construction Cost And Schedule Performance, Michael J. Beach

Theses and Dissertations

Cost and schedule performance are widely accepted in the literature and in industry as effective measures of the success of the project management effort expended. Earned Value Analysis (EVA) offers many metrics to objectively measure cost and schedule performance of many different types of projects. The author utilized EVA to objectively measure the cost and schedule performance of completed United States Air Force (AF) Military Construction (MILCON projects from 1990 to 2005. The impact of Major Command (MAJCOM), Construction Agent (CA), and facility type (CATCODE) and the combination of these variables on the EVA metrics of Cost Performance Index (CPI), …


Factor Analysis Of Interface Problems Among Construction Parties - A Case Study Of Mrt, Rong-Yau Huang, Chin-Tien Huang, Hung Lin, Wen-Hsiang Ku Mar 2008

Factor Analysis Of Interface Problems Among Construction Parties - A Case Study Of Mrt, Rong-Yau Huang, Chin-Tien Huang, Hung Lin, Wen-Hsiang Ku

Journal of Marine Science and Technology–Taiwan

With the rapid development of technology and the increasingly bigger size of constructions, the involved parties are required to pay more attention to all types of difficult interface problems than ever before. By considering the mass rapid transit system (MRTS) as an example, several problems resulting from complicated mechanical, electrical, civil, and track interfaces led to enormously extra losses in the construction process. Accordingly, this paper intends to use quantitative methods to categorize a variety of interface problems in the MRTS construction projects as well as identify their individual impacts in order to clarify these interface problems. The analysis results …


Application Of Maximum-Efficiency Tracking Control To Backlight Module Based On Phase-Locked Loop Technique, Chang-Hua Lin, Ying Lu Mar 2008

Application Of Maximum-Efficiency Tracking Control To Backlight Module Based On Phase-Locked Loop Technique, Chang-Hua Lin, Ying Lu

Journal of Marine Science and Technology–Taiwan

Maximum-efficiency tracking control applied in the backlight module is proposed in this paper. The backlight system incorporates a phase-locked loop (PLL) as a feedback mechanism to promote both the system efficiency and stability. To overcome the drawbacks of the conventional electromagnetic transformer and to miniaturize the backlight module, the piezoelectric transformer (PT) is adopted for driving the cold cathode fluorescent lamp (CCFL). To avoid the system efficiency decreases due to the temperature effect of PT, the PLL is utilized to track immediately the optimal operating frequency of PT for achieving maximum output efficiency under various ambient temperatures. The feedback parameter …


Utility Of Daily Vs. Monthly Large-Scale Climate Data: An Intercomparison Of Two Statistical Downscaling Methods, Edwin P. Maurer, Hugo G. Hidalgo Mar 2008

Utility Of Daily Vs. Monthly Large-Scale Climate Data: An Intercomparison Of Two Statistical Downscaling Methods, Edwin P. Maurer, Hugo G. Hidalgo

Civil, Environmental and Sustainable Engineering

Downscaling of climate model data is essential to local and regional impact analysis. We compare two methods of statistical downscaling to produce continuous, gridded time series of precipitation and surface air temperature at a 1/8-degree (approximately 140 km2 per grid cell) resolution over the western U.S. We use NCEP/NCAR Reanalysis data from 1950–1999 as a surrogate General Circulation Model (GCM). The two methods included are constructed analogues (CA) and a bias correction and spatial downscaling (BCSD), both of which have been shown to be skillful in different settings, and BCSD has been used extensively in hydrologic impact analysis. Both methods …


Evaluation Of The Applicability Of The Interactive Highway Safety Design Model To Safety Audit Of Two-Lane Rural Highways, Kaitlin Chuo Mar 2008

Evaluation Of The Applicability Of The Interactive Highway Safety Design Model To Safety Audit Of Two-Lane Rural Highways, Kaitlin Chuo

Theses and Dissertations

The Interactive Highway Safety Design Model (IHSDM) is a suite of software developed by the Federal Highway Administration (FHWA) for monitoring and analyzing two-lane rural highways in the United States. As IHSDM is a fairly "young" program a limited amount of research has been conducted to evaluate its practicability and reliability. To determine if IHSDM can be adopted into the engineering decision making process in Utah, a study was conducted under the supervision of the Utah Department of Transportation (UDOT) to evaluate its applicability to audit safety of two-lane rural highways in Utah. IHSDM consists of six modules: Policy Review …


Analytical And Numerical Methodology For Modeling Temperatures In Landfills, James L. Hanson, Wei-Lien Liu, Nazli Yesiller Mar 2008

Analytical And Numerical Methodology For Modeling Temperatures In Landfills, James L. Hanson, Wei-Lien Liu, Nazli Yesiller

Civil and Environmental Engineering

Analytical and numerical approaches have been developed for modeling temperatures in municipal solid waste landfills. Steps for model formulation and details of boundary conditions are described. The formulation was based on a transient conductive heat transfer analysis. Conventional earth temperature theories were modified for landfill systems by incorporating heat generation functions representing biological decomposition of wastes. Finite element analysis was used for general modeling and parametric evaluations. Thermal properties of materials were determined using field observations and data reported in literature. The boundary conditions consisted of seasonal temperature cycles at the ground surface (established using near-surface field measurements) and constant …


Engineering Controlled Low Strength Materials Using Scrap Tire Rubber, Tammie Cheung, Daniel C. Jansen, James L. Hanson Mar 2008

Engineering Controlled Low Strength Materials Using Scrap Tire Rubber, Tammie Cheung, Daniel C. Jansen, James L. Hanson

Civil and Environmental Engineering

An investigation was conducted to determine the influence of recycled scrap tire rubber on the engineering properties of controlled low strength material (CLSM). With control over the ultimate compressive strength of CLSMs being key for applications such as backfilling utility trenches where re-excavation is often necessary, incorporation of scrap tire rubber into the CLSM mixture is a viable way to limit the ultimate strength. The work presented includes the results of 27 batches of CLSM, 20 of which included scrap tire rubber. The variables included: cement content, fly ash content, and fractional replacement of sand with scrap tire rubber. Results …


Portland Cement Concrete Pavement Over Rubblized Pcc, James Crovetti Mar 2008

Portland Cement Concrete Pavement Over Rubblized Pcc, James Crovetti

Transportation Reports with the Wisconsin Department of Transportation

This report has presented findings of research conducted to determine the viability of constructing Portland cement concrete pavements over rubblized PCC. Rubblization of aged PCC pavements is a common technique for in-place recycling of these pavements. For the vast majority of applications, the rubblized PCC layer is surfaced with hot mix asphalt (HMA). The use of Portland cement concrete as a surfacing material offers designers another option which may provide good performance and be cost-effective under certain conditions.

The current concrete pavement design procedures utilized by WisDOT allow for the incorporation of a rubblized PCC base layer and an increase …


Climate Change Scenarios For The California Region, Daniel R. Cayan, Edwin P. Maurer, Michael D. Dettinger, Mary Tyree, Katharine Hayhoe Mar 2008

Climate Change Scenarios For The California Region, Daniel R. Cayan, Edwin P. Maurer, Michael D. Dettinger, Mary Tyree, Katharine Hayhoe

Civil, Environmental and Sustainable Engineering

To investigate possible future climate changes in California, a set of climate change model simulations was selected and evaluated. From the IPCC Fourth Assessment, simulations of twenty-first century climates under a B1 (low emissions) and an A2 (a medium-high emissions) emissions scenarios were evaluated, along with occasional comparisons to the A1fi (high emissions) scenario. The climate models whose simulations were the focus of the present study were from the Parallel Climate Model (PCM1) from NCAR and DOE, and the NOAA Geophysical Fluid Dynamics Laboratory CM2.1 model (GFDL). These emission scenarios and attendant climate simulations are not “predictions,” but rather are …


Now Hear This! What All Environmental Engineers Should Know About Noise Control, Harold M. Cota, Mark Bastasch, Roger Wayson, Tracy Thatcher Mar 2008

Now Hear This! What All Environmental Engineers Should Know About Noise Control, Harold M. Cota, Mark Bastasch, Roger Wayson, Tracy Thatcher

Civil and Environmental Engineering

Noise is an is an that affects almost everyone. And even though environmental engineers are often called on to deal with noise-related problems, most of them receive little or no academic training in noise control. This primer suggests why all environmental engineers should know something about noise control, what they need to know, and where they can find the necessary information.


A New Approach For Nonlinear Finite Element Analysis Of Reinforced Concrete Structures With Corroded Reinforcements, Mohsen A. Shayanfar, Amir Safiey Mar 2008

A New Approach For Nonlinear Finite Element Analysis Of Reinforced Concrete Structures With Corroded Reinforcements, Mohsen A. Shayanfar, Amir Safiey

Publications

A new approach for nonlinear finite element analysis of corroded reinforcements in reinforced concrete (RC) structures is elaborated in the article. An algorithmic procedure for producing the tension-stiffening curve of

RC elements taking into consideration most of effective parameters, e.g.: the rate of steel bar corrosion, bond-slip behavior, concrete cover and amount of reinforcement, is illustrated. This has been established on both experimental and analytical bases. This algorithm is implemented into a nonlinear finite element analysis program. The abilities of the resulted program have been studied by modeling some experimental specimens showing a reasonable agreement between the analytical and experimental …


Resistance To It Change In The Aec Industry: An Individual Assessment Tool, Kirsten Davis, Anthony D. Songer Mar 2008

Resistance To It Change In The Aec Industry: An Individual Assessment Tool, Kirsten Davis, Anthony D. Songer

Construction Management Faculty Publications and Presentations

Numerous IT adoption studies within the AEC industry identify issues with individuals resisting IT changes. Current change models often only look at organizations and tasks and frequently neglect the individuals involved. The limitations in existing change models and the criticality of people issues in the successful implementation of change necessitates the investigation of individual resistance to IT change.

Change management theory and attitude-behavior connections provide a framework to study variables associated with impeding/promoting the use of technologies. Data collected from a 50-person sample of the AEC population allowed reductions of the attitudes, fears, and beliefs variables. Reducing the variables indicative …


A Fast Adaptive Wavelet Scheme In Rbf Collocation For Nearly Singular Potential Pdes, Nicolas Ali Libre, Arezoo Emdadi, Edward J. Kansa, Mohammad Shekarchi, Mohammad Rahimian Mar 2008

A Fast Adaptive Wavelet Scheme In Rbf Collocation For Nearly Singular Potential Pdes, Nicolas Ali Libre, Arezoo Emdadi, Edward J. Kansa, Mohammad Shekarchi, Mohammad Rahimian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We present a wavelet based adaptive scheme and investigate the efficiency of this scheme for solving nearly singular potential PDEs. Multiresolution wavelet analysis (MRWA) provides a firm mathematical foundation by projecting the solution of PDE onto a nested sequence of approximation spaces. The wavelet coefficients then were used as an estimation of the sensible regions for node adaptation. The proposed adaptation scheme requires negligible calculation time due to the existence of the fast DiscreteWavelet Transform (DWT). Certain aspects of the proposed adaptive scheme are discussed through numerical examples. It has been shown that the proposed adaptive scheme can detect the …


Effects Of Ionic Strength, Temperature, And Ph On Degradation Of Selected Antibiotics, Keith A. Loftin, Craig D. Adams, Michael T. Meyer, Rao Surampalli Mar 2008

Effects Of Ionic Strength, Temperature, And Ph On Degradation Of Selected Antibiotics, Keith A. Loftin, Craig D. Adams, Michael T. Meyer, Rao Surampalli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Aqueous degradation rates, which include hydrolysis and epimerization, for chlorretracycline (CTC), oxytetracycline (OTC), tetracycline (TET), lincomycin (LNC), sulfachlorpyridazine (SCP), sulfadimethoxine (SDM), sulfathiazole (STZ), trimethoprim (TRM), and tylosin a (TYL) were studied as a function of ionic strength (0.0015, 0.050, or 0.084 mg/L as Na2HPO4), temperature (7, 22, and 35°C), and pH (2, 5, 7, 9, and 11). Multiple linear regression revealed that ionic strength did not significantly affect (α = 0.05) degradation rates for all compounds, but temperature and pH affected rates for CTC, OTC, and TET significand (α = 0.05). Degradation also was observed for TYL at pH 2 …


Investigation Of Voids/Cracking On The I-275 Twin Bridges Over The Ohio River In Kenton County - Phase I, Brad Rister, Theodore Hopwood Ii Mar 2008

Investigation Of Voids/Cracking On The I-275 Twin Bridges Over The Ohio River In Kenton County - Phase I, Brad Rister, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

An evaluation of the northbound bridge approach and the abutment wall of (Combs-Hehl) bridge on I-275 in Kenton County was conducted in September 2007. The inspection consisted of using ground penetrating radar to look for potential voids beneath the concrete approach slab and a video camera inspection to inspect the void space beneath the pier cap/concrete beam in front of the abutment wall.

Results of field testing and recommendations:

A possible void approximately 1-2 inches in depth resides under the approach slab approximately 105 feet before the bridge abutment in the fast lane. It is recommended that this section be …


Evaluation Of Noise Impact Mitigation Protocols To Support Css, Ted Grossardt, Lou Cohn, Al Harris, Keiron Bailey, John Ripy Mar 2008

Evaluation Of Noise Impact Mitigation Protocols To Support Css, Ted Grossardt, Lou Cohn, Al Harris, Keiron Bailey, John Ripy

Kentucky Transportation Center Research Report

This research project developed and evaluated practical ways of involving the public in context sensitive sound mitigation strategies. The integrated use of photo montage, PowerPoint presentation, linked traffic sound files, and audience response systems demonstrated that significant visual and aural differences could be clearly portrayed and clear preferences could be expressed by citizens and professionals alike, even where the choice menu was quite complex.


Improved Method Of Using Traffic Estimates To Evaluate Intersection Improvements, Karen Schurr, Krishna C. Movva, Linna Zhang Mar 2008

Improved Method Of Using Traffic Estimates To Evaluate Intersection Improvements, Karen Schurr, Krishna C. Movva, Linna Zhang

Nebraska Department of Transportation: Research Reports

No abstract provided.


Evaluation Of A Modified Three Cable Guardrail Adjacent To Steep Slope, Ryan J. Terpsma, Dean L. Sicking, Karla A. Polivka, John R. Rohde, Ronald K. Faller, John D. Reid Mar 2008

Evaluation Of A Modified Three Cable Guardrail Adjacent To Steep Slope, Ryan J. Terpsma, Dean L. Sicking, Karla A. Polivka, John R. Rohde, Ronald K. Faller, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.


Bs News Mar 2008

Bs News

Building Services Engineering

No abstract provided.


A Strategy For Reducing The Impact Of Driving Under Influence Of Intoxicants In Portland, Oregon, Christopher Monsere, Delia Chi Mar 2008

A Strategy For Reducing The Impact Of Driving Under Influence Of Intoxicants In Portland, Oregon, Christopher Monsere, Delia Chi

Civil and Environmental Engineering Faculty Publications and Presentations

Driving under the influence of intoxicants (DUII) applies to operating a vehicle under the influence of any substance that can impair driving performance. Nationally and locally there is a strong desire to reduce the societal impacts of this significant social problem. The trend in U.S. alcohol-related motor vehicle crashes was generally decreasing in the mid to late 1980’s but has remained fairly flat since the early 1990s. In 1982, approximately 60% of all US traffic fatalities were alcohol-related. By 1994, this had decreased to 43% but in the decade that followed it has changed little. In 2005, nearly 39% of …


Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger Mar 2008

Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger

Theses and Dissertations

Environmental managers utilize a variety of tools when assessing lotic systems for stressors attributed to anthropogenic sources. Stream deposited sediment has been recognized as one of the major stressors affecting streams in the U.S. The detrimental effect on aquatic biota of sediment depositing within the interstitial spaces of stream substrate (embeddedness) has been established, yet lacking is an effective in situ method of quantifying embeddedness over short time periods. The goal of this research was to develop a short-term embeddedness (EMB) quantification method that can be linked to benthic macroinvertebrate health. Such a method would be a valuable tool when …