Open Access. Powered by Scholars. Published by Universities.®

Civil and Environmental Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

2009

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 301 - 330 of 655

Full-Text Articles in Civil and Environmental Engineering

Vehicle Tire-Pavement Interfacial Surface Pressure Measurements And Assessments, Jerry G. Rose, Timothy E. Guenther May 2009

Vehicle Tire-Pavement Interfacial Surface Pressure Measurements And Assessments, Jerry G. Rose, Timothy E. Guenther

Kentucky Transportation Center Research Report

This report examines a method of using Piezoelectric Pressure-Sensitive Ink (Tekscan) Pressure Measurement System to evaluate vehicle tire pressures that are exerted on the surface of pavements. Upgrades to the Tekscan system facilitated refinements from previous research and allows for procedures to be modified in order to account for these improvements. Among the most significant advances is the ability to select various sensitivities within the software program. In addition to the methodology of evaluating calibration practices, sensitivity and sensor selection, it was important to determine how accurately the pressures and wheel loads can be computed from pavement tests. Also examined …


Highway-Railway At-Grade Crossings: Rideability Measurements And Assessments, Jerry G. Rose, Thomas W. Witt, Aaron F. Renfro, Nathan E. Ridgeway May 2009

Highway-Railway At-Grade Crossings: Rideability Measurements And Assessments, Jerry G. Rose, Thomas W. Witt, Aaron F. Renfro, Nathan E. Ridgeway

Kentucky Transportation Center Research Report

This report provides two analyses for obtaining a quantitative means of rating the condition of railroad‐highway at‐grade crossings based on their measured roughness. Phase One of this report examined 11 crossings in the Lexington area by use of a laser based inertial profiler from the Kentucky Transportation Cabinet (KYTC) and a Face Rolling Dipstick. Phase Two was a continuation of Phase One with 26 crossings examined using inertial profilers from both the KYTC and the National Center of Asphalt technology. Objective ratings based on rideability were obtained and wheelpath profiles were measured for each crossing. Several roughness indexes were computed …


Highway-Railway At-Grade Crossing Structures: Optimum Design/Installation Practices And Management Program – An Overview, Jerry G. Rose May 2009

Highway-Railway At-Grade Crossing Structures: Optimum Design/Installation Practices And Management Program – An Overview, Jerry G. Rose

Kentucky Transportation Center Research Report

Replacing and rehabilitating highway-railway at-grade crossings represent major track maintenance expenses for the U.S. highway governmental agencies and railroad industry. The ideal crossing system is one that will maintain a smooth surface and stable highway/trackbed for a long period of time minimizing costly and inconvenient disruptions to highway and rail traffic.

This report describes the consensus goals for, and the development of, a cooperative, fast-track crossing renewal system for an ideal highway-railway crossing management program. The performance-based process utilizes premium structural materials and construction techniques to provide long-term, cost effective, smooth, and safe crossings. Specifically stressed is the desirability of …


Highway-Railway At-Grade Crossings: Long-Term Settlement Measurements And Assessments, Jerry G. Rose, Mary G. Swiderski, Justin S. Anderson, Lindsay A. Walker May 2009

Highway-Railway At-Grade Crossings: Long-Term Settlement Measurements And Assessments, Jerry G. Rose, Mary G. Swiderski, Justin S. Anderson, Lindsay A. Walker

Kentucky Transportation Center Research Report

The purpose of this research was to evaluate the long-term settlements for a wide variety of at-grade crossings. Twenty-four highway crossings were monitored to determine the effects of enhanced support on minimizing long-term settlements of the crossing surfaces. Settlements of the rail and highway approaches to the crossing areas were compared to settlements of the common crossing areas over an average service period of three years. Long-term settlements of crossings with traditional all-granular support materials were compared to crossings with enhanced support. The enhanced support was provided by substituting a layer of asphalt (termed underlayment) for the all-granular subballast layer. …


Environmental Durability Of Reinforced Concrete Deck Girders Strengthened For Shear With Surface Bonded Carbon Fiber-Reinforced Polymer, Christopher Higgins, Matthew R. Dawson, Mikal M. Mitchell, Gautam Sopal, A. Ekin Senturk May 2009

Environmental Durability Of Reinforced Concrete Deck Girders Strengthened For Shear With Surface Bonded Carbon Fiber-Reinforced Polymer, Christopher Higgins, Matthew R. Dawson, Mikal M. Mitchell, Gautam Sopal, A. Ekin Senturk

TREC Final Reports

This research investigated the durability of carbon fiber-reinforced polymer composites (CFRP) used for shear strengthening reinforced concrete deck girders. Large beams were used to avoid accounting for size effects in the data analysis. The effort included determining the role of freeze-thaw, moisture, and fatigue on structural performance and developing analytical design procedures that account for durability.

The results showed that moisture infiltration behind the CFRP, combined with freeze-thaw, was critical in reducing shear panel stiffness and shear capacity. Long-term moisture exposure alone produced only a minor decrease in shear capacity. Freeze-thaw, combined with fatigue, had little effect on shear capacity …


An Investigation Of Human Induced Vibrations On Clemson Memorial Stadium, Benjamin Morris May 2009

An Investigation Of Human Induced Vibrations On Clemson Memorial Stadium, Benjamin Morris

All Theses

Human induced stadium vibrations have become of increasing concern to design engineers and facility managers as more energetic crowds and increasingly efficient structures have increased the likelihood of serviceability issues. The 'in-time' bouncing of spectators due to music has caused one such issue in the south upper deck of Clemson University's Memorial Stadium. To gain an understanding of the severity of vibrations in Memorial Stadium, a combination of experimental and analytical modeling is utilized. Data collected by an array of accelerometers installed on a main post tensioned precast cantilever girder provides a season and a half of response histories in …


Reliability Of Light Frame Roof Systems Subject To High Winds, Angelina Gleason May 2009

Reliability Of Light Frame Roof Systems Subject To High Winds, Angelina Gleason

All Theses

Recent hurricane damages have devastated coastal communities and focused national attention on hurricane damage mitigation. Structural damage is one of the most significant impacts of a hurricane. Even small levels of structural damage can result in large economic losses; when gaps open in the roof system, rain water can leak in, ruining the contents of the structure and rendering it uninhabitable although it is still standing. In order to prevent these secondary damages from occurring, a better understanding of the roof system behavior is essential. This research aims to ascertain the behavior of the roof system by determining the influence …


The Influence Of Carbon Source Types And Nitrate On The Performance Of The Enhanced Biological Phosphorus Removal Systems, Shamim Ara Begum May 2009

The Influence Of Carbon Source Types And Nitrate On The Performance Of The Enhanced Biological Phosphorus Removal Systems, Shamim Ara Begum

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focuses on two issues in enhanced biological phosphorus removal (EBPR). The first issue encompasses the effect of the type of carbon sources (i.e. volatile fatty acids and non volatile fatty acids) on the microbiology of EBPR. The second issue deals with the influence of denitrification on EBPR. Few studies have been performed to investigate these two issues. The recent findings on these areas are summarized below to establish the knowledge gaps this dissertation attempted to address. Details on the specific findings can be found in the literature review portion of this proposal.


Metering Secondary Water In Residential Irrigation Systems, Gregory L. Richards May 2009

Metering Secondary Water In Residential Irrigation Systems, Gregory L. Richards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of residential secondary or dual water systems for irrigation purposes is common in the western United States where water supplies are scarce. While the use of non-potable water in secondary systems has successfully curtailed demands on potable systems, experience has shown that overall water use actually increases with the introduction of a secondary supply because users commonly pay a fixed fee and have unlimited water use. While water metering and billing effectively reduce water use, there are two main obstacles to the widespread installation of meters in secondary systems.

The first obstacle is that standard residential water meters …


Behavior Of Prestressed Concrete Bridge Girders, Franklin B. Angomas May 2009

Behavior Of Prestressed Concrete Bridge Girders, Franklin B. Angomas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For this research, prestress losses were monitored in six HPC bridge girders. These measured losses were compared to predicted losses according to four sources. Prestress loss predictive methods considered for this research were: 1- AASHTO LRFD 2004, 2- AASHTO LRFD 2004 Refined, 3- AASHTO LRFD 2007, and 4- AASHTO LRFD Lump Sum method. On the other hand, the camber prediction methods used in the present research were: 1- Time dependent method described in NCHRP Report 496, 2- PCI multiplier method, and 3- Improved PCI Multiplier method. For the purpose of this research, long-term prestress losses were monitored in select girders …


Measurement Of Air Pollutant Emissions From A Confined Poultry Facility, Olumuyiwa Omotola Ogunlaja May 2009

Measurement Of Air Pollutant Emissions From A Confined Poultry Facility, Olumuyiwa Omotola Ogunlaja

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Air emissions from animal feeding operations have become a growing concern. Much work has been done to study occupational exposures and the exhaust concentrations associated with animal facilities; however little information has been provided about air quality around the houses. Ammonia (NH3 ), ethanol (EtOH), nitrous oxide (N2O), carbon dioxide (CO2), and particulate matter (PM 2.5 and PM10) emissions were monitored in two different buildings for laying hens in northern Utah. Over the six-month sampling period, the observed average temperatures for the west and east fan banks of the high-rise building were 21.2±4 …


Sediment Transport Impacts Upon Culvert Hydraulics, Wade H. Goodridge May 2009

Sediment Transport Impacts Upon Culvert Hydraulics, Wade H. Goodridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sedimentation buildup and accumulation can cause serious impediments to the hydraulic capacity of culvert systems. There has not been any significant research to date regarding the behavior of bed load transport nor the implications of bed forms upon the hydraulics associated with culvert flow. The primary objective of this study was to investigate how sediment transport occurs in a culvert and to then develop a methodology and test setup to successfully investigate this sediment transport. The investigation was limited to studying culvert and pipeline transport of alluvial material in sand and gravel sizes.

This dissertation develops a semi-empirical bed load …


Finite Element Modeling Of Full Depth Precast Concrete Transverse Bridge Deck Connections, Jacob Logan Julander May 2009

Finite Element Modeling Of Full Depth Precast Concrete Transverse Bridge Deck Connections, Jacob Logan Julander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The frequent use of precast concrete panels has been used to decrease the construction time for bridges. Cracking often occurs at the transverse connections of these panels, resulting in corrosion, and decreased bridge life. Previous laboratory testing of these connections was performed at Utah State University for the Utah Department of Transportation to determine maximum shear and moment capacities, cracking behavior, and cracking loads for five different connections. Two connections are Utah Department of Transportation standard connections. These connections are post tensioned and welded tie connection using shear studs. A different type of welded tie connection using rebar was also …


Development Of Mechanically Stabilized Earth (Mse) Wall Inspection Procedure For Failure Mode Analysis And Risk Assessment, Ryan Bruce Maw May 2009

Development Of Mechanically Stabilized Earth (Mse) Wall Inspection Procedure For Failure Mode Analysis And Risk Assessment, Ryan Bruce Maw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A large component of the State of Utah's transportation network involves the use of MSE walls, which have proven useful in infrastructure for their reduced costs and footprint compared to other alternatives. As effective as MSE walls have been in responding to demands in transportation, they also have inherent challenges. For the majority of MSE walls the structure is limited in observation as structural components are buried as part of the soils mass. This inability to observe at can lead to the development of complex failure mechanisms, which can be difficult to assess and anticipate. As society becomes increasingly reliant …


Water Allocation For Agricultural Use Considering Treated Wastewater, Public Health Risk, And Economic Issues, Ahmed E. Al-Juaidi May 2009

Water Allocation For Agricultural Use Considering Treated Wastewater, Public Health Risk, And Economic Issues, Ahmed E. Al-Juaidi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increasing demand on limited water resources calls for more efficient and improved approaches to maximize the benefits of water use. Typically, agricultural water use has the largest share among all water use sectors. Therefore, finding the best agricultural water management alternatives to maximize profit and reduce financial and other related risks under limited water availability is essential. Treated wastewater is an important alternative source of agricultural water which has the potential to reduce the stress on freshwater sources from urban and industrial sectors. Thus, further research on optimal agricultural water management is needed to find the best management alternatives that …


Energy Losses In Cross Junctions, Zachary B. Sharp May 2009

Energy Losses In Cross Junctions, Zachary B. Sharp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solving for energy losses in pipe junctions has been a focus of study for many years. Although pipe junctions and fittings are at times considered "minor losses" in relation to other energy losses in a pipe network, there are cases where disregarding such losses in flow calculations will lead to errors. To facilitate these calculations, energy loss coefficients (K-factors) are commonly used to obtain energy losses for elbows, tees, crosses, valves, and other pipe fittings. When accurate K-factors are used, the flow rate and corresponding energy at any location in a pipe network can be calculated. K-factors are well defined …


Investigation Of Feasibility And Potential Mechanisms For The Bioregeneration Of Perchlorate Laden Gel-Type Anion Exchange Resin, Arjun Krishna Venkatesan May 2009

Investigation Of Feasibility And Potential Mechanisms For The Bioregeneration Of Perchlorate Laden Gel-Type Anion Exchange Resin, Arjun Krishna Venkatesan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The feasibility and potential mechanisms for the bioregeneration of perchlorate laden gel-type anion exchange resin were investigated in this study. Bioregeneration is a sustainable process when compared to one time use of resin and disposal by incineration. Batch and bench-scale bioregeneration experiments were performed to evaluate the feasibility of the process and to gain insight into potential mechanisms that control gel-type resin bioregeneration. The results of the bioregeneration tests suggested that the initial phase of the bioregeneration process is controlled by kinetics, while the later phase is controlled by diffusion. Higher perchlorate load in the resin had a positive effect …


Development Of Strategies For Enhanced In Situ Bioremediation Of High Concentrations Of Halogenated Methanes, Huifeng Shan May 2009

Development Of Strategies For Enhanced In Situ Bioremediation Of High Concentrations Of Halogenated Methanes, Huifeng Shan

All Dissertations

ABSTRACT
Bioremediation of high concentrations of halomethanes e.g., carbon tetrachloride (CT), trichlorofluoromethane (CFC-11) and chloroform (CF) has seldom been addressed before and remains highly challenging. A microcosm study was conducted to investigate bioremediation strategies for groundwater contaminated with CT (6 to 10 mg/L), CFC-11 (1 to 26 mg/L), CF (3-500 mg/L), and 1,1-dichloroethene (1,1-DCE; up to 9 mg/L) at a former industrial site in California. Biostimulation with corn syrup and catalytic amounts of vitamin B12 was demonstrated as a feasible remedial strategy and bioaugmentation with B12 represents the most promising bioremediation method of the ones studied. Halomethane transformation …


Characterizing Liquefaction Resistance Of Aged Sand Deposits, Hossein Hayati May 2009

Characterizing Liquefaction Resistance Of Aged Sand Deposits, Hossein Hayati

All Dissertations

Presented in this dissertation are the results of various studies conducted to characterize the liquefaction resistance of aged natural deposits. The data considered include laboratory and field test results from sites in five countries with particular focus on multiple locations in the South Carolina Coastal Plain.
A new liquefaction potential map of the peninsula of Charleston, South Carolina, is presented. Liquefaction potential is expressed in terms of the liquefaction potential index (LPI) developed by Iwasaki et al. and calculated using 44 cone penetration test (CPT) profiles. The CPT profiles are supplemented with information from the 1:24,000 scale geologic map by …


An Examination Of Confined Aquifer Gradient Behavior Under Pumping Conditions, Stefanie Fountain May 2009

An Examination Of Confined Aquifer Gradient Behavior Under Pumping Conditions, Stefanie Fountain

All Dissertations

Accurate and reliable estimates of groundwater flow and contaminant transport models are dependent on an understanding of the aquifer properties used to create the models. The borehole flowmeter has been used with increasing frequency at a variety of sites to produce high resolution vertical hydraulic conductivity (K(z)) distributions [Boggs et al. 1990; Rehfeldt et al. 1989b; Molz et al. 1989, Boman et al. 1997; Dinwiddie et al. 1999]. In theory, the validity of measurements obtained using borehole flowmeters is contingent on the hydraulic head gradients near the well at each discrete depth resulting from the pumping-induced flow having reached quasi-steady-state. …


The North American Transportation Security Center – Technology Prototype Gap Analysis, Steven Douglas Kreis, Michael M. Barclay May 2009

The North American Transportation Security Center – Technology Prototype Gap Analysis, Steven Douglas Kreis, Michael M. Barclay

Kentucky Transportation Center Research Report

Executive Summary

There are over 800,000 hazardous materials (hazmat) shipments over the nation’s roads each day. According to the U.S. Department of Homeland Security (DHS), terrorist activity related to the transportation of hazardous materials represents a significant threat to public safety and the nation’s critical infrastructure. Specifically, the federal government has identified the government’s inability to track hazmat shipments on a real-time basis as a significant security vulnerability.

In 2004, the U.S. Federal Motor Carrier Safety Administration (FMCSA) completed a study to determine if “smart truck” technology such as GPS tracking, wireless modems, panic buttons, and onboard computers could be …


Earthquake Resistance Of Integral Abutment Bridges, Robert J. Frosch, Michael E. Kreger, Aaron M. Talbott May 2009

Earthquake Resistance Of Integral Abutment Bridges, Robert J. Frosch, Michael E. Kreger, Aaron M. Talbott

JTRP Technical Reports

intermediate length bridges. Integral abutment construction eliminates joints and bearings which reduce long-term maintenance costs. However, in the absence of joints and bearings, the bridge abutments and foundations must be able to accommodate lateral movements from thermal expansion and contraction of the superstructure and from seismic events. Previous research has focused on the response to thermal expansion and contraction. The current research examines the response of integral abutment bridges to seismic loading. A field investigation was conducted to examine the response of an integral abutment to lateral loading from thermal expansion and contraction. The results were used to calibrate analytical …


Bs News May 2009

Bs News

Building Services Engineering

No abstract provided.


The I-70 Greenfield Rest Area Wetland Projects, Shih-Chieh Kao, Ting Pong Chang, Rebeka Sultana, Thomas Konopka, Rao S. Govindaraju, Barry Partridge May 2009

The I-70 Greenfield Rest Area Wetland Projects, Shih-Chieh Kao, Ting Pong Chang, Rebeka Sultana, Thomas Konopka, Rao S. Govindaraju, Barry Partridge

JTRP Technical Reports

On-site treatment of wastewater at highway rest areas poses some unique and difficult challenges because of the rural locale, high variability in wastewater flow rate and strength, and lack of knowledgeable personnel on-site. As a potential alternative, a constructed subsurface wetland system was built at the I-70 rest stop nearby Greenfield, Indiana, in 2003. This wetland system, mainly composed of three wetland cells, also includes draw-and-fill and recirculation mechanisms to increase oxygen transfer to the wastewater and improve the overall treatment performance. Special considerations for highway rest areas have been emphasized. A dynamic hydraulic model was developed to help characterize …


Vertical Boil Propagation From A Submerged Estuarine Sill, C. Chris Chickadel, Alexander R. Horner-Devine, Stefan A. Talke, Andrew T. Jessup May 2009

Vertical Boil Propagation From A Submerged Estuarine Sill, C. Chris Chickadel, Alexander R. Horner-Devine, Stefan A. Talke, Andrew T. Jessup

Civil and Environmental Engineering Faculty Publications and Presentations

Surface disruptions by boils during strong tidal flows over a rocky sill were observed in thermal infrared imagery collected at the Snohomish River estuary in Washington State. Locations of boil disruptions and boil diameters at the surface were quantified and are used to test an idealized model of vertical boil propagation. The model is developed as a two-dimensional approximation of a three-dimensional vortex loop, and boil vorticity is derived from the flow shear over the sill. Predictions of boil disruption locations were determined from the modeled vertical velocity, the sill depth, and the over-sill velocity. Predictions by the vertical velocity …


Laboratory Testing Of Precast Bridge Deck Panel Transverse Connections For Use In Accelerated Bridge Construction, Scott D. Porter May 2009

Laboratory Testing Of Precast Bridge Deck Panel Transverse Connections For Use In Accelerated Bridge Construction, Scott D. Porter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Precast concrete bridge deck panels have been used for decades to accelerate bridge construction. Cracking of the transverse connection between panels is a common problem that can damage deck overlays and cause connection leaking leading to corrosion of lower bridge elements.

To better understand the behavior of bridge deck transverse female-to-female connections, shear and moment lab testing were performed at Utah State University for the Utah Department of Transportation. Two existing UDOT connections were tested, a welded stud connection and a post tensioned connection. A variation of the welded connection using rebar was also tested. In addition, two new curved …


Comparison Of Data Collection And Methods For The Approximation Of Streambed Thermal Properties, Jonathan D. Bingham May 2009

Comparison Of Data Collection And Methods For The Approximation Of Streambed Thermal Properties, Jonathan D. Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When approximating heat transfer through a streambed, an understanding of the thermal properties of the sediments is essential (e.g., thermal conductivity, specific heat capacity, and density). Even though considerable research has been completed in this field, little has been done to establish appropriate standard data collection approaches or to compare modeling methods for approximating these properties. Three mixture models were selected for comparison against each other and against a bed conduction model (SEDMOD). Typical data collection approaches were implemented for use in the mixture models while numerous data collection approaches were employed for use within SEDMOD. Sediment samples were taken …


Hydraulics Of Ideal Drip Irrigation Systems, Evan J. Thompson May 2009

Hydraulics Of Ideal Drip Irrigation Systems, Evan J. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hydraulics of IDEal drip irrigation system components were analyzed under controlled laboratory conditions and the results can be applied to the design of IDEal systems. The hydraulic loss coefficient for the lateral-submain connector valves was determined based on laboratory measurements. It was found that the hydraulic loss due to friction in the lay-flat laterals can be accurately estimated with standard friction loss equations using a smaller effective diameter based on the wall thickness and inlet pressure head. The equivalent length barb loss, expressed as an equivalent length of lateral, was calculated for button emitters, as well as for micro-tubes …


College Of Engineering Senior Design Competition Spring 2009, University Of Nevada, Las Vegas May 2009

College Of Engineering Senior Design Competition Spring 2009, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …


Development Of A Methodology For Evaluating And Anticipating Improvised Explosive Device Threat Activity Using A Fault Tree Based Process, Benjamin Bennett May 2009

Development Of A Methodology For Evaluating And Anticipating Improvised Explosive Device Threat Activity Using A Fault Tree Based Process, Benjamin Bennett

All Dissertations

This document is a redacted version of the original dissertation titled 'Development of a Methodology for Evaluating and Anticipating Improvised Explosive Device Threat Activity Using a Fault Tree Based Process.' To allow for publication, information was removed which was considered sensitive in nature or which could be used by those who employ the Improvised Explosive Device, to negate any advantage gained by this research. The complete un-redacted dissertation is available (with proper vetting) to those whishing to further develop the concepts outlined in this document. Those interested in obtaining access to the complete document should contact the Joint IED Defeat …