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Civil and Environmental Engineering Commons

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2008

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Articles 1 - 30 of 307

Full-Text Articles in Civil and Environmental Engineering

Dynamic Properties Of Railway Track And Its Components : A State-Of-The-Art Review, Sakdirat Kaewunruen, Alexander Remennikov Dec 2008

Dynamic Properties Of Railway Track And Its Components : A State-Of-The-Art Review, Sakdirat Kaewunruen, Alexander Remennikov

Faculty of Engineering - Papers (Archive)

Recent findings indicate one of major causes of damages, which is attributed to the resonant behaviours, in a railway track and its components. Basically, when a railway track is excited to generalised dynamic loading, the railway track deforms and then vibrates for certain duration. Dynamic responses of the railway track and its components are the key to evaluate the structural capacity of railway track and its components. If a dynamic loading resonates the railway track’s dynamic responses, its components tend to have the significant damage from excessive dynamic stresses. For example, a rail vibration could lead to defects in rails …


Dynamic Design Guidelines For Prestressed Concrete Sleepers, Alexander Remennikov, Martin H. Murray, Sakdirat Kaewunruen Dec 2008

Dynamic Design Guidelines For Prestressed Concrete Sleepers, Alexander Remennikov, Martin H. Murray, Sakdirat Kaewunruen

Faculty of Engineering - Papers (Archive)

Current design philosophy, outlined in AS 1085.14, is based on the analysis of permissible stresses resulting from quasi-static wheel loads and essentially the static response of concrete sleepers. In general, cracking can incur when the bottom fibre stress is larger than tensile strength of concrete. Premature cracking of prestressed concrete sleepers has been detected in railway tracks. The major cause of cracking is the infrequent but high-magnitude wheel loads produced by a small percentage of “out-of-round” wheels or railhead surface defects, which are crudely accounted for in AS 1085.14 by a single load factor. Based on the current design method, …


Development Of High Performance Precast/Prestressed Bridge Girders, Amin K. Akhnoukh Dec 2008

Development Of High Performance Precast/Prestressed Bridge Girders, Amin K. Akhnoukh

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Demand continues to increase for bridges with long spans and shallow depths. Due to safety concerns, four-span overpasses are being replaced with two span overpasses to avoid placement of piers near the highway shoulders. In the meantime, the bridge profile is restricted due to existing businesses nearby. Thus, nearly the same superstructure depth must be used for double the span length. This dissertation focuses on topics aiming at providing precast prestressed concrete girders with the shallowest possible depth for a given span. It forms parts of larger projects conducted by the University of Nebraska for the Nebraska Department of Roads …


Green Roofs For A Green Town: Possibilities Of Green Roof Implementation In The Town Of Normal, Lindsey Sihau, '09 Dec 2008

Green Roofs For A Green Town: Possibilities Of Green Roof Implementation In The Town Of Normal, Lindsey Sihau, '09

Outstanding Senior Seminar Papers

Green roofs have been growing in popularity throughout the world. Scientists have been studying them since the 1980’s. This research project reviews the literature regarding both the benefits and barriers to green roof construction and management. Policies around the nation are then examined and analyzed. Suggestions are made regarding possible additions to the local Stormwater Management Policy that would emphasize the importance of sustainable building techniques such as green roofs, and hopefully offer incentive to their implementation.


Integrated Science Assessment For Oxides Of Nitrogen And Sulfur – Ecological Criteria, United States Environmental Protection Agency Dec 2008

Integrated Science Assessment For Oxides Of Nitrogen And Sulfur – Ecological Criteria, United States Environmental Protection Agency

United States Environmental Protection Agency: Staff Publications

This Integrated Science Assessment (ISA) is a synthesis and evaluation of the most policy-relevant science that forms the scientific foundation for the review of the secondary (welfare-based) national ambient air quality standards (NAAQS) for oxides of nitrogen (NOx) and oxides of sulfur (SOx). The Clean Air Act definition of welfare effects includes, but is not limited to, effects on soils, water, wildlife, vegetation, visibility, weather, and climate, as well as effects on man-made materials, economic values, and personal comfort and well-being. The current secondary NAAQS for SOx, set in 1973, is a 3-hour average …


Fatigue Risks In The Connections Of Sign Support Structures: Phase 1, Christopher Foley, Baolin Wan, Mathew Weglarz, Matthew Hellenthal, Jordan Komp, Andrew Smith, Joseph Schmidt Dec 2008

Fatigue Risks In The Connections Of Sign Support Structures: Phase 1, Christopher Foley, Baolin Wan, Mathew Weglarz, Matthew Hellenthal, Jordan Komp, Andrew Smith, Joseph Schmidt

Transportation Reports with the Wisconsin Department of Transportation

Wisconsin sought to assess the risk of fatigue-induced fracture in its existing sign support structures designed before the latest AASHTO specifications that included fatigue design. A framework for assessing fatigue-induced fracture risk is developed and detailed synthesis of fatigue testing of connections is conducted. Statistical analysis of tests conducted since 1970 is made and models for characterizing uncertainty in the fatigue life of these connections are proposed. Recommendations regarding further fatigue testing (specimen configuration, number and stress range) are given. Statistical models for wind speed and direction are developed using historical records obtained through the National Climatic Data Center for …


Detection Of Voids In Prestressed Concrete Bridges Using Thermal Imaging And Ground-Penetrating Radar, David G. Pollock, Kenneth J. Dupuis, Benjamin Lacour, Karl R. Olsen Dec 2008

Detection Of Voids In Prestressed Concrete Bridges Using Thermal Imaging And Ground-Penetrating Radar, David G. Pollock, Kenneth J. Dupuis, Benjamin Lacour, Karl R. Olsen

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Thermal imaging and ground-penetrating radar was conducted on concrete specimens with simulated air voids. For the thermal imaging inspections, six concrete specimens were constructed during the month of June 2007 to simulate the walls of post-tensioned box girder bridges. The objective was to detect simulated air voids within grouted post-tensioning ducts, thus locating areas where the post-tensioning steel strands are vulnerable to corrosion. The most important deduction taken from these inspections was that PT-ducts and simulated voids were more detectable in the 20 cm (8 in.) thick specimens than in the 30 cm (12 in.) thick specimens. While inspections of …


Multiple Radar Data Merging In Hydro-Nexrad, Witold F. Krajewski, Bong Chul Seo, Anton Kruger, Piotr Domaszczynski, Gabriele Villarini, James A. Smith Dec 2008

Multiple Radar Data Merging In Hydro-Nexrad, Witold F. Krajewski, Bong Chul Seo, Anton Kruger, Piotr Domaszczynski, Gabriele Villarini, James A. Smith

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Hydro-NEXRAD merging algorithms include two options: (1) data-based merging; and (2) product-based merging. Data-based merging algorithm takes volume scan reflectivity data from all radars involved through preprocessing algorithm that performs volume data quality control, interpolates data to synchronize temporal scale between individual radars, and finally combines data onto a common geographic grid. Reflectivity values for a given location are assigned by a weighting function with respect to the distance from the radar. This single reflectivity field is then converted to rainfall amounts using a user-requested standard approach. In product-based merging algorithm reflectivity data from multiple radars are all converted …


Quantitative Rrna-Targeted Solution-Based Hybridization Assay Using Peptide Nucleic Acid Molecular Beacons, Xu Li, Eberhard Morgenroth, Lutgarde Raskin Dec 2008

Quantitative Rrna-Targeted Solution-Based Hybridization Assay Using Peptide Nucleic Acid Molecular Beacons, Xu Li, Eberhard Morgenroth, Lutgarde Raskin

Department of Civil and Environmental Engineering: Faculty Publications

The potential of a solution-based hybridization assay using peptide nucleic acid (PNA) molecular beacon (MB) probes to quantify 16S rRNA of specific populations in RNA extracts of environmental samples was evaluated by designing PNA MB probes for the genera Dechloromonas and Dechlorosoma. In a kinetic study with 16S rRNA from pure cultures, the hybridization of PNA MB to target 16S rRNA exhibited a higher final hybridization signal and a lower apparent rate constant than the hybridizations to nontarget 16S rRNAs. A concentration of 10 mM NaCl in the hybridization buffer was found to be optimal for maximizing the difference between …


How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere Dec 2008

How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere

TREC Project Briefs

Researchers from Portland State University evaluate Oregon’s Implementation of System-Wide Adaptive Ramp Metering (SWARM).


Hydro-Nexrad: An Updated Overview And Metadata Analysis, Witold F. Krajewski, Anton Kruger, Piotr Domaszczynski, Charles Gunyon, Bong Chul Seo, Radosław Goska, James A. Smith, Mary Lynn Beack, Matthias Steiner Dec 2008

Hydro-Nexrad: An Updated Overview And Metadata Analysis, Witold F. Krajewski, Anton Kruger, Piotr Domaszczynski, Charles Gunyon, Bong Chul Seo, Radosław Goska, James A. Smith, Mary Lynn Beack, Matthias Steiner

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hydro-NEXRAD is a prototype system that allows hydrologists to obtain user-specified rainfall data for their research. These data are based on observations collected by the national network of WSR-88D radars, known as NEXRAD. Users interact with Hydro-NEXRAD through a web-based interface that has map-based components for spatial navigation, calendar- and time series plot components for temporal navigation and a menu-based component for selection of processing options. Through the interface, users browse the Hydro-NEXRAD metadata and select data of interest. As the system is approaching the point of being fully operational, the authors and a group of test users have evaluated …


Investigation Of The Effective Use Of Warning Lights On Indiana Department Of Transportation (Indot) Vehicles And Equipment, Bob Mccullouch, Brandon Stevens Dec 2008

Investigation Of The Effective Use Of Warning Lights On Indiana Department Of Transportation (Indot) Vehicles And Equipment, Bob Mccullouch, Brandon Stevens

JTRP Technical Reports

This study was requested by INDOT to determine if current lighting packages used on INDOT maintenance vehicles, specifically snow plow vehicles, can be improved with other commercially available products. Different light products were obtained from various vendors, mounted on INDOT vehicles, and visual comparisons were performed under various lighting and weather conditions by a team of observers. The comparison evaluations were performed revealing that other light packages, LED models for most options, were brighter and certain colors more visible. The preferred light models are recommended. These recommendations were forwarded to appropriate individuals that make these decisions at INDOT. Implementation is …


Use Of Micropiles For Foundations Of Transportation Structures Final Report, Hoyoung Seo, Monica Prezzi Dec 2008

Use Of Micropiles For Foundations Of Transportation Structures Final Report, Hoyoung Seo, Monica Prezzi

JTRP Technical Reports

In pile design, piles must be able to sustain axial loads from the superstructure without bearing capacity failure or structural damage. In addition, piles must not settle or deflect excessively in order for the serviceability of the superstructures to be maintained. In general, settlement controls the design of piles in most cases because, by the time a pile has failed in terms of bearing capacity, it is very likely that serviceability will have already been compromised. Therefore, realistic estimation of settlement for a given load is very important in design of axially loaded piles. This notwithstanding, pile design has relied …


Approach Slope For Midwest Guardrail System, Erin A. Johnson, Karla A. Lechtenberg, Dean L. Sicking, Robert W. Bielenberg M.S.C.E., E.I.T., Ronald K. Faller, John R. Rohde, John D. Reid Dec 2008

Approach Slope For Midwest Guardrail System, Erin A. Johnson, Karla A. Lechtenberg, Dean L. Sicking, Robert W. Bielenberg M.S.C.E., E.I.T., Ronald K. Faller, John R. Rohde, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.


Cable Median Barrier Guidelines, Dean L. Sicking, Karla A. Lechtenberg, Francisco Daniel Benicio De Albuquerque Dec 2008

Cable Median Barrier Guidelines, Dean L. Sicking, Karla A. Lechtenberg, Francisco Daniel Benicio De Albuquerque

Nebraska Department of Transportation: Research Reports

No abstract provided.


Liquefaction Behavior Of Mississippi River Silts, Ali M. Izadi, Ronaldo Luna, Richard Wesley Stephenson Dec 2008

Liquefaction Behavior Of Mississippi River Silts, Ali M. Izadi, Ronaldo Luna, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Civil Infrastructure Built on Alluviums and Recent Deposits, Such as Dams, Contain Significant Amount of Silts. the Static and Dynamic Behavior of These Fine-Grained Soils Has Been Investigated Less Than the Clay-Like or Sand-Like Soils. Low Plasticity Silts (PI = 6) Obtained East of St. Louis in Illinois Are Known as Loess that Has Been Re-Deposited by Water in the Floodplains of the Mississippi River. These Silts Were Reconstituted in the Laboratory by Slurry at Water Content above the Liquid Limit and Then Consolidated to an Initial Effective Stress. the Initial Laboratory Characterization under Monotonic Loading Included a Series of …


The North American Transportation Security Center, Steven Douglas Kreis, Michael M. Barclay Dec 2008

The North American Transportation Security Center, Steven Douglas Kreis, Michael M. Barclay

Kentucky Transportation Center Research Report

No abstract provided.


Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn Dec 2008

Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

A System-Wide Adaptive Ramp Metering (SWARM) system has been implemented in the Portland, Oregon metropolitan area, replacing the previous pre-timed ramp-metering system that had been in operation since 1981. SWARM has been deployed on six major corridors and operates during the morning and afternoon peak hours. This report presents results of a "before" and "after" evaluation of the performance of two freeway corridors as part of ongoing efforts to measure the benefits of the new SWARM system, as compared to the pre-timed system. The study benefited from using the existing regional data, surveillance and communications infrastructure in addition to a …


Alternative Land Use Patterns To Minimize Congestion (Volume 3: Empirical Study Of Mixed Land Use Traditional Neighborhoods), Li Jin, Jon D. Fricker Dec 2008

Alternative Land Use Patterns To Minimize Congestion (Volume 3: Empirical Study Of Mixed Land Use Traditional Neighborhoods), Li Jin, Jon D. Fricker

JTRP Technical Reports

Urban sprawl creates serious traffic congestion. Alternative land use patterns may be the best solution. New Urbanists claim that, by placing frequently-visited sites within walking distance of homes and creating a pleasant walking environment, people are more willing to choose non-motorized transportation mode to do such activities.

Part I of this study investigated the ability of travel demand models to estimate the impacts of alternative land use patterns. Part II conducted an economic viability analysis for a mixed land use neighborhood and collected land use preferences at meetings of neighborhood associations. The objective in Part III was to evaluate the …


High-Performance Concrete Bridge Decks: A Fast-Track Implementation Study, Volume 1: Structural Behavior, Robert J. Frosch, Timothy S. Aldridge Dec 2008

High-Performance Concrete Bridge Decks: A Fast-Track Implementation Study, Volume 1: Structural Behavior, Robert J. Frosch, Timothy S. Aldridge

JTRP Technical Reports

Transverse cracking of concrete bridge decks is problematic in numerous states. Cracking has been identified in the negative and positive moment regions of bridges and can appear shortly after opening the structure to live loads. To improve the service life of the bridge deck as well as decrease maintenance costs, changes to current construction practices in Indiana are being considered. A typical bridge deck was instrumented which incorporated the following: increased reinforcement amounts, decreasing reinforcement spacing, and high-performance, low-shrinkage concrete. The low shrinkage concrete was achieved using a ternary concrete mix. The objective of this research was to determine the …


Trade-Off Analysis Methodology For Asset Management, Qiang Bai, Samuel Labi, Zongzhi Li Dec 2008

Trade-Off Analysis Methodology For Asset Management, Qiang Bai, Samuel Labi, Zongzhi Li

JTRP Technical Reports

In an era that is characterized by funding limitations, increased stakeholder participation, and the need for increased accountability and transparency, transportation agencies seek to ensure that comprehensive evaluation processes are identified and used for decision-making. Consistent with such processes is the incorporation of multiple performance criteria from different program areas, optimization of decisions under constrained budgets, and investigation of trade-offs between program areas, performance measures, budgetary levels, risk levels, and performance thresholds. To help INDOT carry out these processes, this study developed theoretical constructs for scaling and amalgamation of the different performance measures, and for analyzing the different kinds of …


Safety And Operational Impacts Of Alternative Intersections, Andrew P. Tarko, Mike Inerowicz, Brandon Lang Dec 2008

Safety And Operational Impacts Of Alternative Intersections, Andrew P. Tarko, Mike Inerowicz, Brandon Lang

JTRP Technical Reports

As the degradation of service at some conventional intersections increases, there becomes a need for alternative solutions other than expensive interchanges. Many alternative intersections have been proposed in the past. Under certain traffic and local conditions some solutions are more promising than other. In some cases, the conventional intersection may still be the optimal choice. The presented research focused on developing guidelines that would help planners and designers identify the most promising solutions for further analysis. This objective has been addresses in two ways. Firstly, the existing knowledge on alternative intersections has been identified. Secondly, the performance of conventional and …


Alternative Land Use Patterns To Minimize Congestion (Volume 2: Evaluating The Feasibility Of New Urbanism In An Existing Neighborhood), Huei Koh, Jon D. Fricker Dec 2008

Alternative Land Use Patterns To Minimize Congestion (Volume 2: Evaluating The Feasibility Of New Urbanism In An Existing Neighborhood), Huei Koh, Jon D. Fricker

JTRP Technical Reports

Urban sprawl creates serious traffic congestion. Alternative land use patterns may be the best solution. New Urbanists claim that, by placing frequently-visited sites within walking distance of homes and creating a pleasant walking environment, people are more willing to choose non-motorized transportation mode to do such activities.

Part I of this study investigated the ability of travel demand models to estimate the impacts of alternative land use patterns. Part II conducted an economic viability analysis for a mixed land use neighborhood and collected land use preferences at meetings of neighborhood associations. The objective in Part III was to evaluate the …


Alternative Land Use Patterns To Minimize Congestion (Volume 1: Comparative Analysis Of Mixed Land Use And Separated Land Use Neighborhoods), Amica Bose, Jon D. Fricker Dec 2008

Alternative Land Use Patterns To Minimize Congestion (Volume 1: Comparative Analysis Of Mixed Land Use And Separated Land Use Neighborhoods), Amica Bose, Jon D. Fricker

JTRP Technical Reports

Urban sprawl creates serious traffic congestion. Alternative land use patterns may be the best solution. New Urbanists claim that, by placing frequently-visited sites within walking distance of homes and creating a pleasant walking environment, people are more willing to choose non-motorized transportation mode to do such activities.

Part I of this study investigated the ability of travel demand models to estimate the impacts of alternative land use patterns. Part II conducted an economic viability analysis for a mixed land use neighborhood and collected land use preferences at meetings of neighborhood associations. The objective in Part III was to evaluate the …


Methods Of Safety Improvements At Coordinated Signals, Wei Li, Andrew P. Tarko Dec 2008

Methods Of Safety Improvements At Coordinated Signals, Wei Li, Andrew P. Tarko

JTRP Technical Reports

In this research, the safety impact of arterial signal coordination is investigated. Based on the findings, procedures are proposed to incorporate safety considerations into signal coordination design. In addition, a software tool is developed to facilitate the use of the research findings. Signal coordination has been extensively employed as a tool to optimize an arterial system’s mobility performance, commonly measured by the total number of vehicle stops and the time of delays. Although vehicle crashes at signalized intersections have long been recognized as a major safety threat, studies to date have been limited locally to non-coordinated signals or the noncoordinated …


Incorporating Spatial Data And Gis To Improve Sea Of Land Use Plans: Opportunities And Limitations: Case Studies In The Republic Of Ireland, Ainhoa Gonzalez Del Campo Nov 2008

Incorporating Spatial Data And Gis To Improve Sea Of Land Use Plans: Opportunities And Limitations: Case Studies In The Republic Of Ireland, Ainhoa Gonzalez Del Campo

Doctoral

This research aimed at establishing whether spatial data and Geographic Information Systems (GIS) can contribute to Strategic Environmental Assessment (SEA). To achieve this, an integrated GISEA approach was developed and applied to a number of spatial planning SEAs in the Republic of Ireland. The practical applicability of the approach was examined, evaluating the potential benefits derived from using spatial data and GIS in SEA and assessing the potential barriers to an effective GIS use. The implementation of the SEA Directive incorporated a new dimension into plan-making by calling for the assessment of potential environmental effects that may derive from implementing …


Dynamic Responses Of Marine Risers/Pipes Transporting Fluid Subject To Top End Excitations, J. Leklong, S. Chucheepsakul, S. Kaewunruen Nov 2008

Dynamic Responses Of Marine Risers/Pipes Transporting Fluid Subject To Top End Excitations, J. Leklong, S. Chucheepsakul, S. Kaewunruen

Faculty of Engineering - Papers (Archive)

This paper deals with the dynamic responses to top end excitation of marine risers/pipes conveying internal fluid. The marine riser is often used as a flexible link between undersea bore head and subsurface offshore platform. The tidal waves and the changes of sea level consistently excite its top end connected to a floating vessel. In order to carry out the performance-based design of the marine risers, the evaluation of their dynamic responses to top end excitations is imperative. In this study, the marine riser is simulated using twodimensional beam elements. Energy functional of the marine risers conveying fluids is derived …


Influence Of Joint Stiffness On The Free Vibrations Of A Marine Riser Conveying Fluid, S. Kaewunruen, T. Mccarthy, J. Leklong, S. Chucheepsakul Nov 2008

Influence Of Joint Stiffness On The Free Vibrations Of A Marine Riser Conveying Fluid, S. Kaewunruen, T. Mccarthy, J. Leklong, S. Chucheepsakul

Faculty of Engineering - Papers (Archive)

The marine risers are generally used as the main transport means for economic materials and resources discovered undersea. In general, the marine risers are secured at either an offshore platform or a vessel. Both ends of the riser are to be adjusted to obey with the design criteria but in many cases their rotational stiffness is hardly set free for the hinge connection. This paper integrates the analytical investigation and the design consideration for the effects of end supports on the free vibrations of a marine riser conveying fluid. It is well known that resonances of marine risers/pipes can cause …


Improving Concept Learning In Green Building By Addressing Students' Learning Styles And Prior Knowledge, Sreelatha Chunduri Nov 2008

Improving Concept Learning In Green Building By Addressing Students' Learning Styles And Prior Knowledge, Sreelatha Chunduri

FIU Electronic Theses and Dissertations

In green building there is a requirement for the collaboration of students from different disciplines in order to solve challenging problems. Successful collaboration depends on the establishment of a common understanding of the subject matter among those involved. To gain common understanding concept learning is critical. A concept learning process may be improved when factors affecting it are addressed. Prior knowledge and learning styles of the students may influence the way they learn concepts. This thesis is focused on studying the relationship between a concept learning process and prior knowledge and learning styles of students. An experiment was conducted by …


Inelastic Performance Of Screw Connected Cfs Strap Braced Walls, Kostadin Velchev, Colin A. Rogers Nov 2008

Inelastic Performance Of Screw Connected Cfs Strap Braced Walls, Kostadin Velchev, Colin A. Rogers

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.