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Articles 421 - 450 of 1513
Full-Text Articles in Civil and Environmental Engineering
Airport Runway Heating System, Greg Wang, Curtis Reedy
Airport Runway Heating System, Greg Wang, Curtis Reedy
Electrical Engineering
According to the Federal Aviation Administration, flight delays cost airlines $22 billion annually (Rapajic 16). Snow and ice buildup on the tarmacs are a major contributor to these delays in regions where freezing weather conditions are common. Current solutions such as anti-freeze chemicals and snowplows are ineffective and costly. Implementing a radiant heating system, specifically pipes running hot liquid within or below the runways, can help maintain the surface above freezing temperatures. Such a system has yet to be installed in a functioning airport because of its complexity and high cost. However, the FAA provides funding for infrastructure improvements, and …
Another Look At The Collapse Of Skyline Plaza At Bailey’S Crossroads, Virginia, Jeffrey Schellhammer, Norbert Delatte, Paul A. Bosela
Another Look At The Collapse Of Skyline Plaza At Bailey’S Crossroads, Virginia, Jeffrey Schellhammer, Norbert Delatte, Paul A. Bosela
Civil and Environmental Engineering Faculty Publications
On March 2, 1973, the Skyline Plaza apartment building in Bailey’s Crossroads, Virginia collapsed while under construction. The Occupational Health and Safety Administration (OSHA) requested an investigation from the National Bureau of Standards [(NBS); now the National Institute of Standards and Technology (NIST)]. The NBS team concluded that the most likely cause of the collapse was a punching shear failure of the 23rd floor slab. The two factors that contributed to this were premature removal of shores below the 23rd floor slab, and the low strength of the 23rd floor concrete in the area supporting the weight of the 24th …
Performance Of Reinforced Concrete Beams Strengthened With Mechanically-Fastened Composite System Under Corrosive Environment, Amna Zaid Suwaid Al Nassibi
Performance Of Reinforced Concrete Beams Strengthened With Mechanically-Fastened Composite System Under Corrosive Environment, Amna Zaid Suwaid Al Nassibi
Theses
This study examines the effects of corrosion exposure on the flexural response of reinforced concrete (RC) beams strengthened with a powder-actuated fastened (PAF) composite system. Twenty-one RC beams were constructed and tested to failure under four-point bending. The corroded beams were subjected to 30, 60, and 100 days of accelerated corrosion that corresponded to measure tensile steel mass losses of 6, 11 and 18% respectively. Other test parameters included width of fiber reinforced polymer (FRP) composite strip, fastener length, and number of fasteners rows.
For the non-corroded beams, the PAF-FRP system resulted in up to 24% increase in beam flexural …
Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs
Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs
Master's Theses
The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings.
The work of this thesis is divided into four phases. First, …
Seismic Rehabilitation Of Steel Moment Frames Vulnerable To Soft-Story Failures Through Implementation Of Rocking Cores, Juan Carlos Sanchez
Seismic Rehabilitation Of Steel Moment Frames Vulnerable To Soft-Story Failures Through Implementation Of Rocking Cores, Juan Carlos Sanchez
Master's Theses
During seismic events, inefficient steel moment frame building systems may exhibit soft-story failures. This thesis focuses on development and validation of a seismic retrofit strategy for avoiding soft-story failures in low-rise and mid-rise steel moment frame buildings. The considered retrofit strategy consists of a sufficiently stiff Rocking Core (RC) pinned to the foundation and pin connected to the existing frame. For demonstration purposes, two representative benchmark steel moment frames, which are modified from the three- and nine-story pre-Northridge steel moment frames designed for Los Angeles in the SAC Steel Project, are considered. Finite Element (FE) models of the benchmark buildings …
Evaluation Of Alternative Snowplowable Markers And Snowplowing Procedures, Kenneth R. Agent, Jerry G. Pigman
Evaluation Of Alternative Snowplowable Markers And Snowplowing Procedures, Kenneth R. Agent, Jerry G. Pigman
Kentucky Transportation Center Research Report
The objectives of this study were to investigate viable alternatives to the currently approved snowplowable raised pavement marker and alternative methods and equipment used to snowplow roadways. The study included evaluating any potential durable and effective pavement marker that is not disruptive to snowplowing operations and alternative snowplowing procedures and equipment that do not damage pavement delineation and pavements. Implementation possibilities resulting from the research project include a recessed snowplowable marker and improved/alternative snowplowing procedures and equipment.
The alternative snowplowable markers included in the evaluation were the current steel casting marker and a recessed marker. The evaluations confirmed past research …
1976 Montreal Olympics: Case Study Of Project Management Failure, Ashish Patel, Paul A. Bosela, Norbert Delatte
1976 Montreal Olympics: Case Study Of Project Management Failure, Ashish Patel, Paul A. Bosela, Norbert Delatte
Civil and Environmental Engineering Faculty Publications
A successful engineering project must include its timely and economic completion. A project management failure can lead to delays and cost overruns. One example of a project that greatly exceeded its projected budget is the construction of the multiple facilities for the 1976 Olympic Games in Montreal. These included the Olympic Stadium, a velodrome for bicycle events, and the Olympic Village to house the athletes. This case study reviews the circumstances of the cost increases and the design decisions and other circumstances that led to them. The difficulties were brought on by an unrealistic schedule to complete the facilities before …
Reliability-Based Bridge Assessment Using Enhanced Monte Carlo To Simulate Extreme Traffic Loading, Bernard Enright, Donya Hajializadeh, Eugene J. Obrien
Reliability-Based Bridge Assessment Using Enhanced Monte Carlo To Simulate Extreme Traffic Loading, Bernard Enright, Donya Hajializadeh, Eugene J. Obrien
Conference papers
A framework is presented for the assessment of the safety of a bridge deck under actual traffic loading using an enhanced Monte Carlo method which attempts to reduce computational cost while preserving the advantages of more conventional, computationally intensive, simulation. To generate the bridge loading scenarios, an extensive Weigh-in-Motion (WIM) database is used to calibrate a sophisticated simulation model of two-directional traffic. Traffic and vehicle characteristics are generated from statistical distributions derived from measured traffic data. Two examples are used in this study to assess the usefulness and accuracy of the enhanced method. In the first, a simple example is …
Evaluation Of Wet-Nighttime Delineation, Kenneth R. Agent
Evaluation Of Wet-Nighttime Delineation, Kenneth R. Agent
Kentucky Transportation Center Research Report
The objective of the research was to evaluate the alternative methods which could potentially provide effective and durable delineation of roadways during wet-nighttime conditions. Following is a summary of conclusions for future procedures and materials which should be considered as a method to provide effective lane delineation during wet-nighttime conditions.
- Snowplowable raised pavement markers should continue to be used on interstates and parkways. The installation process must ensure the markers are not placed on or adjacent to the pavement joint.
- Lenses in the steel casting raised pavement markers should be replaced on a three-year cycle. The condition of the castings …
Use Of A Gateway In-Street Sign Treatment To Increase Yielding To Pedestrians At Crosswalks, Miles K. Bennett
Use Of A Gateway In-Street Sign Treatment To Increase Yielding To Pedestrians At Crosswalks, Miles K. Bennett
Masters Theses
An important goal to reduce the number of collisions between motorists and pedestrians is to increase motorist’s yielding right-of-way to pedestrians in crosswalks. The current study addresses this goal. A Gateway installation of instreet signs (one in-street sign installed between the two travel lanes in each direction and one on both edges of the roadway in each direction) was evaluated on multilane roads. The first experiment compared the efficacy of adding multiple in-street signs used in a gateway configuration with a single sign between the two travel lanes in each direction. The second experiment compared the in-street sign gateway treatment …
Spatial Factors Impacting Non-Motorized Exposures And Crash Risks, Farhad Abasahl
Spatial Factors Impacting Non-Motorized Exposures And Crash Risks, Farhad Abasahl
Masters Theses
This research investigates spatial factors, that impact non-motorized exposures and crashes, and examines the relationship between exposure at signalized intersections and crash frequencies involving pedestrians and bicycles at a census tract level. The four Michigan cities of Ann Arbor, East Lansing, Flint and Grand Rapids are examined. After completing an extensive literature review to provide a list of required data, 92 intersections are selected from the four cities to collect pedestrian and bicyclist counts. Five-year crash records, special attractions, non-motorized facilities and transportation infrastructure data for the four cities are gathered for the four cities. This data are later mapped …
Gis-Based Flood Analysis For Adequate Flood Mitigation In An Unplanned Urban Area; The Case Of Pikine Dagoudane In Dakar County, Senegal, Sokhna Helene Diop
Gis-Based Flood Analysis For Adequate Flood Mitigation In An Unplanned Urban Area; The Case Of Pikine Dagoudane In Dakar County, Senegal, Sokhna Helene Diop
Masters Theses
Since 1989, Pikine Dagoudane, in the suburbs of Dakar City has faced several flooding events, resulting in economic loss, environmental degradation and severe disturbance of the social life of the residents. The mitigation programs implemented have not appeared to provide any relief since 2000. Review of the existing literature on the crisis has revealed that the general scale of the studies, and the insufficient attention to some of the major factors could be accounted for such little efficiency. This thesis applies a different approach, based on a small area and focusing mainly on topographic characteristics, to provide a better understanding …
Residential Fire Sprinkler Design For The Phi Kappa Psi Fraternity House, Nolan Frost
Residential Fire Sprinkler Design For The Phi Kappa Psi Fraternity House, Nolan Frost
BioResource and Agricultural Engineering
This senior project discusses the design of a residential fire sprinkler system for a local fraternity house. The design follows NFPA 13D code, and contains design calculations, design drawings, material specifications, and cost analysis. The design was completed with the intention of being used for the installation of a fire sprinkler system in the house.
Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh
Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh
Civil and Environmental Engineering and Engineering Mechanics Faculty Publications
Identifying factors that affect crash injury severity and understanding how these factors affect injury severity is critical in planning and implementing highway safety improvement programs. Factors such as driver-related, traffic-related, environment-related and geometric design-related were considered when developing statistical models to predict the effects of these factors on the severity of injuries sustained from motor vehicle crashes at merging and diverging locations. Police-reported crash data at selected freeway merging and diverging areas in the state of Ohio were used for the development of the models. A generalized ordinal logit model also known as partial proportional odds model was applied to …
Optimized Aggregates Gradations For Portland Cement Concrete Mix Designs Evaluation, Wally Heyen, Lieska Halsey, Robert Rea, Mick Syslo
Optimized Aggregates Gradations For Portland Cement Concrete Mix Designs Evaluation, Wally Heyen, Lieska Halsey, Robert Rea, Mick Syslo
Nebraska Department of Transportation: Research Reports
No abstract provided.
Dairy Manure Flushwater Treatment By Packed-Bed Anaerobic Digesters, Neal Cary Adler
Dairy Manure Flushwater Treatment By Packed-Bed Anaerobic Digesters, Neal Cary Adler
Master's Theses
Wastewater treatment performance of three pilot-scale packed-bed anaerobic digesters with walnut shell medium was researched for treating dairy freestall barn flushwater. Reciprocation mixing was evaluated as a means to lessen channelization in the media bed and to improve biogas production and organic matter removal at ambient temperatures. Reciprocation has been used in biological nitrogen removal systems to introduce air into the system to repeatedly oxygenate nitrifying biofilm along with mixing (Behrends et al. 2003), but the anaerobic systems benefit from mixing. Two tanks were used in each system, where one was full and one was empty at any given time. …
Nutrient Removal Using Microalgae In Wastewater-Fed High Rate Ponds, Matthew N. Rodrigues
Nutrient Removal Using Microalgae In Wastewater-Fed High Rate Ponds, Matthew N. Rodrigues
Master's Theses
This thesis discusses the mechanisms associated with the removal of organic matter, nitrogen and phosphorus in wastewater-fed high rate algae ponds (HRAP) designed to operate as triplicates. Research was conducted at the San Luis Obispo Water Reclamation Facility (SLOWRF) as a pilot-scale study of nine 30-square meter ponds one foot in depth. During period of study, triplicates were operated at hydraulic retention times (HRT) of 4, 3 or 2-days. Main objectives for the study were to determine minimum HRTs required to achieve secondary and tertiary treatment. Experimental conditions such as CO2 supplementation, nighttime aeration and operation of ponds in …
Boundary Retracement Survey Of Cal Poly’S Serrano Ranch, John Lanfranki
Boundary Retracement Survey Of Cal Poly’S Serrano Ranch, John Lanfranki
BioResource and Agricultural Engineering
No abstract provided.
Design, Construction, And Evaluation Of A Hydraulic Oil Filtration Cart, Eric Steiger
Design, Construction, And Evaluation Of A Hydraulic Oil Filtration Cart, Eric Steiger
BioResource and Agricultural Engineering
This report discusses the design, construction, and evaluation of a hydraulic oil filtration car sponsored by Papich Construction Inc. This company developed the need for a filter cart system to service equipment by flushing and cleaning the oil in hydraulic reservoirs and systems. The opportunity of reviewing an existing product from Caterpillar was taken to obtain basic design parameters. This car however, did not meet all the needs preferred by the service technicians of Papich; thus leading to the idea of a custom filter cart.
The filter cart is composed of a square tube frame sitting on pneumatic no-flat castor …
Starting A Construction Engineering Program At Marquette University, Mark O. Federle
Starting A Construction Engineering Program At Marquette University, Mark O. Federle
Civil and Environmental Engineering Faculty Research and Publications
Marquette University decided to start a Construction Engineering and Management program during the 2007 academic year. An endowed chair, titled the McShane Chair in Construction Engineering and Management, was funded by Jim and Kelly McShane to run the program. After a national search, Mark Federle, an executive with a large construction firm and previous academic experience at Iowa State University, was hired to start the program. The first class of students were enrolled in the fall of 2008. This paper will present the opportunities/challenges in starting a Construction Engineering and Management program. Lessons learned, comparisons to other programs, and other …
Laboratory Evaluation Of A Turn Compensation Control System For A Ground Sprayer, Wesley M. Porter, Jorge A. Rascon, Yeyin Shi, Randal K. Taylor, Paul A. Weckler
Laboratory Evaluation Of A Turn Compensation Control System For A Ground Sprayer, Wesley M. Porter, Jorge A. Rascon, Yeyin Shi, Randal K. Taylor, Paul A. Weckler
Department of Agricultural and Biological Systems Engineering: Faculty Publications
The ability to compensate sprayer nozzle flow across a horizontal boom has the potential to mitigate the problem of inaccurate chemical application rate due to lateral speed differences when sprayers are turning. A laboratory testing platform and procedure were developed and tested with a commercial turn compensation control system for a ground sprayer. Virtual paths consisting of simulated GPS signals representing right and left turns separated by straight segments were simulated with four turning radii (75%, 125%, 250%, and 500%) based on boom width. Actual application rates from 11 nozzles spread across the boom were measured using load cells in …
Volatilization Of Trichloroethylene From Trees And Soil: Measurement And Scaling Approaches, William J. Doucette, H. Klein, J. Chard, Ryan Dupont, W. Plaehn, Bruce Bugbee
Volatilization Of Trichloroethylene From Trees And Soil: Measurement And Scaling Approaches, William J. Doucette, H. Klein, J. Chard, Ryan Dupont, W. Plaehn, Bruce Bugbee
Civil and Environmental Engineering Faculty Publications
Trichloroethylene (TCE) volatilization from leaves, trunk, and soil was measured to assess the significance of these pathways from phytoremediation sites at Travis and Fairchild Air Force Bases. Measurements were scaled temporally and spatially to estimate the annual volatilization of TCE at the Travis (0.82 ± 0.51 kg/yr) and Fairchild sites (0.014 ± 0.008 kg/yr). Volatilization was primarily through the leaf (0.34 ± 0.16 kg/yr at Travis and 0.01 ± 0.06 kg/yr at Fairchild) and soil (0.48 ± 0.36 kg/yr at Travis, 0.003 ± 0.002 kg/yr at Fairchild) pathways. The larger volatilization estimate at Travis was expected because of the site's …
Seismic Rehabilitation Of Steel Concentrically Braced Frames Vulnerable To Soft-Story Failure Through Implementation Of Rocking Cores, Francisco Sanchez-Zamora
Seismic Rehabilitation Of Steel Concentrically Braced Frames Vulnerable To Soft-Story Failure Through Implementation Of Rocking Cores, Francisco Sanchez-Zamora
Master's Theses
Recent research reports that steel Concentrically Braced Frames (CBFs) (even the code-compliant ones) may be susceptible to soft-story failures during strong earthquakes. Such a failure mode causes catastrophic outcomes and should be definitely avoided in practice. This thesis focuses on development and validation of a seismic retrofit strategy for low-rise and mid-rise steel CBFs vulnerable to soft-story failures. The considered retrofit strategy consists of a sufficiently stiff rocking core (RC) pinned to foundation and connected to the existing frame. For demonstration purpose, two representative benchmark steel CBF buildings, which are the three-and six-story CBFs designed forLos Angelesin the SAC Steel …
Seismic Design Manual For Interlocking Compressed Earth Blocks, Nicholas Edwards Kennedy
Seismic Design Manual For Interlocking Compressed Earth Blocks, Nicholas Edwards Kennedy
Master's Theses
Seismic Design Manual for Interlocking Compressed Earth Blocks
Nicholas Edwards Kennedy
This thesis presents a comprehensive seismic design manual to be used to design and construct simple Interlocking Compressed Earth Block (ICEB) structures in seismically active regions. ICEBs are earth blocks made primarily of soil and stabilized with cement. They have female and male stud mechanisms designed to interlock when stacked, eliminating the need for mortar. The blocks can accept reinforcement and grout after they are placed. While ICEB construction is similar to conventional masonry construction, current design code standards for masonry only partially capture the actual behavior of ICEB …
Comparison Of Biofilm Media In Reciprocating Biofilters Treating Dairy Flushwater, Kyle Keoki Tatsuo Fooks
Comparison Of Biofilm Media In Reciprocating Biofilters Treating Dairy Flushwater, Kyle Keoki Tatsuo Fooks
Master's Theses
Reciprocating biofilters known as ReCip is a viable technology to manage nutrients, mainly nitrogen, problems at livestock operations such as swine farms and dairies. Past studies have demonstrated that ReCip is more adept at total nitrogen (TN) removal than traditional subsurface flow wetland systems. The traditional substrate used to attach biomass was rock aggregate; this media may be hard to obtain for some agricultural projects, so alternate substrates are tested and compared with the rock aggregate. The purpose of the study was twofold: first, different biofilm media were tested and compared in terms of treatment performance and, second, the long-term …
Settling Performance In Wastewater Fed High Rate Algae Ponds, Elliott Blake Ripley
Settling Performance In Wastewater Fed High Rate Algae Ponds, Elliott Blake Ripley
Master's Theses
Although high rate algae ponds (HRAPs) are a proven wastewater treatment technology with numerous environmental, social, and economic benefits, their widespread use has been hindered by inconsistent and unreliable settling performance. Hence, the goal of this thesis is to investigate how specific operational parameters affect the settling performance of HRAPs. Nine HRAPs (30 m2 surface area, 0.3 m depth) were operated as three triplicate sets, with each set run on either a 2, 3, or 4 day HRT continuously from January 25, 2012 through April 11, 2013. Settling performance was determined (i) by measuring the TSS of Imhoff cone …
An Innovative Protective Jacket For Structures Subject To Blast Loads: A Comprehensive Experimental And Simulation Study, Nicholas J. Carlson
An Innovative Protective Jacket For Structures Subject To Blast Loads: A Comprehensive Experimental And Simulation Study, Nicholas J. Carlson
Dissertations
As the importance of protective engineering and multi-hazard mitigation design has grown in recent years, the development of an effective structural protection system that aids in the preservation of life safety during blast events is an important topic of research in structural engineering. This protection is especially vital for blast and explosion mitigation, where a vehicle-borne bomb or an improvised explosive device can readily cause an under-designed structure with insufficient redundancy to undergo progressive collapse due to the removal of its first-floor columns. An especially pressing research need is the consideration of structures that require blast protection, but—due to time …
Developing Crash Modification Factors For Operational Parameters On Urban Freeways, Eugene Vida Maina
Developing Crash Modification Factors For Operational Parameters On Urban Freeways, Eugene Vida Maina
Dissertations
Studies have shown that, roadway safety has become an intensively investigated topic with the objective of improved understanding of the factors that cause crashes to occur. However, it has been shown that as traffic volumes continue to increase across the United States, 52% of drivers feel less safe on the roads today more than they did five years ago and that the American public feels that traffic safety is a serious problem that needs both the government and media to pay more attention to this issue.
In response to these public and driver grievances, State and National transportation agencies have …
Evaluating The Safety Effects Of Signal Improvements, Ashley Lynn Dowell
Evaluating The Safety Effects Of Signal Improvements, Ashley Lynn Dowell
Theses and Dissertations
As a result of high crash frequencies on roadways, transportation safety has become a high priority for the United States Department of Transportation and the Utah Department of Transportation. A large percentage of fatal and injury crashes on roadways occur at intersections and traffic signals have been implemented to reduce these severe crashes. There is a need to evaluate the effectiveness of the traffic signal improvements through the development of Crash Modification Factors (CMFs). Recent research has shown that traditional safety evaluation methods have been inadequate in developing CMFs. In recent years, Bayesian statistical methods have been utilized in traffic …
Long-Term Low Do Enriches And Shifts Nitrifier Community In Activated Sludge, Guoqiang Liu, Jianmin Wang
Long-Term Low Do Enriches And Shifts Nitrifier Community In Activated Sludge, Guoqiang Liu, Jianmin Wang
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
In the activated sludge process, reducing the operational dissolved oxygen (DO) concentration can improve oxygen transfer efficiency, thereby reducing energy use. The low DO, however, may result in incomplete nitrification. This research investigated the long-term effect of low DO on the nitrification performance of activated sludge. Results indicated that, for reactors with 10- and 40-day solids retention times (SRTs), complete nitrification was accomplished after a long-term operation with a DO of 0.37 and 0.16 mg/L, respectively. Under long-term low DO conditions, nitrite oxidizing bacteria (NOB) became a better oxygen competitor than ammonia oxidizing bacteria (AOB) and, as a result, no …