Engineering Commons^™

Experimental And Field Monitoring Studies On Recycled Materials As Pavement Bases, Sunil Kumar Sirigiripet

Civil Engineering Theses - Archive

Natural aggregates derived from a variety of source rocks have been used as a road base material. But the extraction of natural aggregates resources is increasingly being constrained by urbanization, increased costs and environmental concerns. Thus, increased amounts of reclaimed materials are being used to supplement natural aggregates in road construction. Recycled Asphalt Pavement (RAP) material is one of the important recycled materials used in the present geotechnical applications. Many agencies are constantly seeking to reap the benefits of utilizing RAP. Main advantages of utilizing RAP include the preservation of the existing profile, conservation of asphalt and aggregate resources, conservation …

The Travel Behavior Of Minority Cohorts In Texas, Gustavo A. Jimenez Vera

Civil Engineering Theses - Archive

Texas is changing dramatically; the most conservative population forecast indicates that Hispanics will account for 50% of the Texas population before 2035. Not only is the number of Hispanics on the rise in Texas, but also the foreign-born share has increased dramatically over the last 15 years. The State of Texas is now a majority minority state, and minority cohorts are expected to grow and become more than 65% of the Texas population before 2035. Transportation professionals in the State of Texas are wondering how these demographic changes will affect the transportation system. To gain an understanding of this, one …

Roadway Shallow Water Flow Modeling By Velocity Distribution, Chirakarn Sirivitmaitrie

Civil Engineering Dissertations - Archive

Manning's equation is a widely used method for determining flow discharge in a channel with unconfined gravity flow. The roughness value, n-value, is a critical factor for Manning equation to obtain the accurate amount of flow. A precise estimation of Manning "n" is difficult to obtain and varies by investigator justification and experience. Flow on a roadway is a type of open channel flow normally determined by Manning's equation. To ensure reliability and highway safety, the hydraulic geometry dimensions such as spread, depth and discharge must be accurately estimated. A Texas Department of Transportation Manning n-value research project collected data …

Simulation, Visualization And Self-Assessment Tools For Enhanced Engineering Education The Stiffness Matrix Method Module For Structural Analysis, Ahmed Ali Mohammed

Civil & Environmental Engineering Theses & Dissertations

Existing macromedia FLASH software which has extensive and exciting simulation and visualization capabilities is utilized to develop the "Stiffness Matrix Method" (SMM) module, which is one of the new topics ( offered for the first time in Spring 2007 semester) covered in a Structural Analysis I course, offered at the junior level at Old Dominion University. The developed software (under the FLASH environment), including tutorial lectures to explain all necessary theoretical backgrounds, formulas, step-by-step computerized procedures and numerical examples are presented in simple, user friendly, visualized, interactive fashion to enhance the student's learning capabilities. Through numerous graphical visualization and simulation …

Capacity Estimation Of Two-Sided Type C Weaves On Freeway, Phong Thanh Vo

Civil Engineering Dissertations - Archive

A weaving section is a common design on major highway facilities that has been an interest to researchers for years. Weaving areas are characterized by frequent lane changes, which significantly reduce the capacity of the freeway system. The 2000 Highway Capacity Manual (HCM) defined weaving capacity as "any combination of flows that causes the density to reach the LOS E/F boundary condition of 43 pcpmpl for freeways" based on configuration, number of lanes in the weaving section, free-flow speed, length of the weave, and volume ratio (VR). However, no research has been focused on the two-sided type C weaves, which …

Dynamic Chracteristics And Stability Analysis Of Muncipal Solid Waste In Bioreactor Landfills, Mohamed Adil Haque

Civil Engineering Dissertations - Archive

Bioreactor landfills are operated to enhance refuse decomposition, gas production, and waste stabilization. The major aspect of bioreactor landfill operation is the recirculation of generated leachate back through the refuse mass. Due to the accelerated decomposition and settlement of solid waste, bioreactor landfills are gaining popularity as an alternative to the conventional landfill designed under Subtitle D regulations. However, recirculation of leachate or addition of water to accelerate the waste decomposition changes the biodegradation and geotechnical characteristics of waste mass. Our understanding of changes in engineering characteristics of solid waste with accelerated decomposition is limited. There is a need to …

Our Legacy Of Neglect: The Longfellow Bridge And The Cost Of Deferred Maintenance, David Westerling, Steve Poftak

Civil Engineering Faculty Publications

The Longfellow Bridge, connecting Boston and Cambridge, is in bad shape, due not only to its age and the ravages of our weather, but also to a troubling and persistent lack of maintenance. Fixing the bridge, in effect paying the bill for our unwillingness to maintain it, is estimated to cost at least $180 million, with the potential for cost overruns reaching into the hundreds of millions. The neglect of the Longfellow Bridge is symptomatic of a problem that encompasses almost all the assets owned by the Commonwealth.

Pilot Study On Real-Time Calculation Of Arrival Type For Assessment Of Arterial Performance, Edward J. Smaglik, Darcy M. Bullock, Anuj Sharma

Department of Civil and Environmental Engineering: Faculty Publications

The Highway Capacity Manual uses the arrival type (AT) as a mechanism to account for the quality of traffic signal coordination in the calculation of delay at a signalized intersection. Although there is much discussion in the literature regarding the accuracy and precision of this approach, the AT parameter provides a simple mechanism for grading the performance of traffic signal coordination. This paper describes data collection limitations of current traffic signal controllers and proposes a procedure where the AT parameter can be calculated by traffic signal controllers in real time. Given that the nation received a score of 61 out …

Bs News

Building Services Engineering

No abstract provided.

Improving Arterial Performance Measurement Using Traffic Signal System Data, Michael Wolfe, Christopher Monsere, Peter Koonce, Robert L. Bertini

Civil and Environmental Engineering Faculty Publications and Presentations

The characterization of the performance of freeways in real time and on a historical basis has been successfully achieved for many years. The ability to characterize arterial performance has been more elusive. Currently numerous applications of traffic management and traveler information systems include freeways but lack the ability to extend their operation to major arterials. This paper describes methods for quantifying arterial performance using data from signal system loop detectors. Included in the array of metrics are traffic density, total delay, predicted travel time, and signal coordination effectiveness. Methods for determining performance in these areas are adapted for use in …

Nyumba Ya Mungu Reservoir System Simulation By Using Hec-Ressim Model, Deogratias Mulungu

Tanzania Journal of Engineering and Technology (TJET)

This research paper focused on estimating effective water and optimization of the NyM reservoir for storage conservation and hydropower generation. Several models were used in the study: the Rainfall-Runoff model, GFFS was used to fill in missing data, and the HEC-ResSim Model and the NWBM for reservoir system simulation and water balance respectively. The effective inflows to the NyM reservoir were determined using HEC-ResSim model and the NWBM used to check the total water loss in the system. For the reservoir system simulation, the HEC-ResSim model was used to estimate water loss through irrigation abstractions in Kikuletwa and Ruvu reaches …

Socio-Economic Impacts Of Water Scarcity In Dar Es Salaam, Tanzania, Shadrack Mwakalila

Tanzania Journal of Engineering and Technology (TJET)

Drought and the resulting low water levels in rivers exacerbate water scarcity conditions in Dar es Salaam city. The result is frequent water rationing in areas served with piped water, sometimes for days or weeks, and low water pressure, which leads residents to resort to other less safe and sometimes more expensive water sources. The frequent and current response to the inadequate piped water supply in Dar es Salaam has been the use of groundwater resources. There are both public and private bore-holes and wells drilling companies in Dar es Salaam.. This paper therefore, presents some socio-economic impacts of water …

Program For The Analysis Of Plane Trusses, John Makunza

Tanzania Journal of Engineering and Technology (TJET)

The ‘TRAP - TRuss Analysis Program’ can assist engineers in the analysis of plane truss-type structures, as well as prove an excellent basis for understanding the “finite – element” method. The Program is completely menu-driven, with all nodes, elements, and load data entered through an input file. TRAP includes plotting for displaying the truss geometry in its original shape showing all nodes and support points. In the analysis process, firstly the structure data; e.g number of nodes, elements, materials and supports are to be defined. Secondly, element properties and support constraints have to be specified. Finally, nodal global loads are …

Optimal Utilization Of Timber Poles As Structural Members Of Formwork, Ladislaus Lwambuka

Tanzania Journal of Engineering and Technology (TJET)

Timber poles of the type “Mirunda” are commonly used in East Africa as formwork support structures for casting of reinforced concrete slabs, beams and canopies. It is also widely known that the “Mirunda” poles as structural members of formwork are massively used without any structural consideration and guidance. This common practice has resulted into wastage of natural resources and escalated construction costs. This study has attempted to establish the load bearing capacity of randomly selected “Mirunda” poles through laboratory testing. Using an existing construction site as a case study, the results have been used to establish the actual number of …

Preliminary Estimates Of Building Cost And The Lowest Evaluated Tender, Harriet Eliufoo

Tanzania Journal of Engineering and Technology (TJET)

The paper has investigated and established to what extent are preliminary estimates of building costs close to the lowest evaluated tender and how geographical proximity influences the variance between preliminary estimate and the lowest evaluated tender. A multiple case study constituting 43 building projects in Tanzania were statistically analysed covering a period from 1995- 1999. Findings reveal a significant variance exists between the quantity surveyor’s preliminary estimate figure and the lowest evaluated tender; and that the variance between the quantity surveyor’s figure and the bidder is small when the proposed building project is geographically closer to the quantity surveyor’s base. …

Civil And Mechanical Engineering Students Learning Mechanics In A Multidisciplinary Engineering Foundation Spiral, Jean Nocito-Gobel, Gregory Broderick, Samuel Bogan Daniels, Michael Collura, Richard Stanley

Engineering and Applied Science Education Faculty Publications

This paper describes how mechanical and civil engineering students are introduced to and develop an understanding of mechanics concepts through a sequence of integrated courses as part of a new curriculum taken during the freshman and sophomore years. The Multi- Disciplinary Engineering Foundation Spiral is a four-semester sequence of engineering courses, matched closely with the development of students’ mathematical sophistication and analytical capabilities and integrated with course work in the sciences. Students develop a conceptual understanding of engineering basics in this series of courses, which stress practical applications of these principles. Mechanics concepts are introduced in a pair of first …

A Hybrid First Year Science Course For Engineering Students – Integrating Biology With Chemistry, David Harding, Pauline Schwartz, Jean Nocito-Gobel, Agamemnon Koutsospyros

Civil Engineering Faculty Publications

Biology is playing an increasingly important role in many engineering fields. With the typical engineering program already having a high credit hour requirement, the question becomes, how to best integrate biology concepts into a packed engineering curriculum. A typical biology course is not likely to introduce the important concepts of biology to engineering students. The solution here is to develop a hybrid course that integrates chemistry and biology. In the course, Chemistry with Applications to Biosystems, the concept is to develop a course that integrally links important concepts of chemistry and biology. The course focuses on the areas of biology …

Data Fusion Technique For Measuring Intersection Delay Using Gps-Enabled Probe Vehicles, Byung-Hee Han

Masters Theses

Intersection control delay is considered a primary measure for determining the level of service at signalized intersections. This thesis develops a technique estimating intersection delay using GPS data from GPS-enabled vehicles. First, this study analyzes existing methods that estimate control delays using GPS data and proposes an improved technique in response to the weakness of those methods. The proposed method estimates the control delay well with better accuracy covering the weaknesses. However, the control delay from the GPS data has a sample size problem for determining the level of service at signalized intersections. Therefore, this thesis proposes a data fusion …

Bs News

Building Services Engineering

No abstract provided.

Evaluating And Adaptive Signal Control System In Gresham, James M. Peters, Jay Mccoy, Robert L. Bertini

Civil and Environmental Engineering Faculty Publications and Presentations

Cities and Counties are faced with increasing traffic congestion due to rapidly increasing population. Like many agencies, the City of Gresham has struggled with how to manage the increasing congestion with limited funds for major roadway widening projects. Gresham has recognized the need to optimize existing system capacity to get the most out of their current transportation system infrastructure investment.

In 2005, the City of Gresham, in cooperation with numerous agencies in the Portland metropolitan area, evaluated a variety of signal control systems including traditional time-of-day coordination, traffic responsive, and adaptive signal control systems. Based on that evaluation, the steering …

Traffic Noise Barrier System: U.S. Patent No. Us 7,220,077 B2, Eric C. Humphries, Stephen D. Barratt, Ronald K. Faller, Keith J. Kurz, Dean L. Sicking

Department of Civil and Environmental Engineering: Faculty Publications

A crashworthy traffic noise barrier system for use alongside a path of traffic, the crashworthy traffic noise barrier system comprises a crashworthy longitudinal barrier extending substantially parallel to the path of traffic and a crashworthy traffic noise barrier wall supported by the longitudinal barrier. The crashworthy traffic noise barrier wall includes a plurality of upstanding posts attached to the traffic noise barrier wall, at least one panel supported between each adjacent pair of posts in the plurality of upstanding posts, and at least one longitudinal beam spaced above a top surface of the longitudinal barrier and extending across the plurality …

Numerical And Physical Modeling Of Turbulent Shear Flows, John Raiford

All Dissertations

This dissertation is an evaluation of popular turbulence schemes; both three dimensional and depth-averaged, and also includes an experimental study on shallow near bed jets. The three dimensional and RNG turbulent closure schemes are evaluated for free and bounded shear flows. For free shear flows (circular and plane turbulent jets), the scheme with standard coefficient performs equally well and in some cases better than the renormalized group scheme in predicting growth rate, decay of centerline velocity and longitudinal velocity profiles. For turbulent kinetic energy across the jet, the inner region is better predicted by the RNG scheme.
The second case …

Evaluating The Impacts Of Accelerated Incident Clearance Tools And Strategies By Harnessing The Power Of Microscopic Traffic Simulation , Ryan Fries

All Dissertations

Traffic incidents cause Americans delay, waste fuel, cause injuries, and create toxic emissions. Transportation professionals have implemented a variety of tools to manage these impacts and researchers have studied their effectiveness, illustrating a wide range between different tools and locations. To improve this state of knowledge, this dissertation sought to 1) identify prominent and effective incident management strategies, 2) model six selected incident management strategies within five highway corridors in South Carolina, and 3) apply benefit-cost analysis to evaluate the impact of various combinations of these strategies.
To meet these objectives, the author evaluated published literature of the selected strategies, …

Experimental Studies To Address Strengths Of Limestone Cores, Sulfate Heave Problems In Limestone Cores And Tunnel Lining, Vivekananda Chikyala

Civil Engineering Theses - Archive

Sulfate induced heave is a common scenario in tunnels located on sedimentary rocks containing Pyrites. Pyrite oxidation produces Gypsum which is a major source of natural sulfates. DART NC -1B tunnel is located in Dallas, north Texas. Dallas is located on sedimentary rocks with high Pyrite content and has a history of sulfate induced heave problems in several projects. In spring 2005 & 2006, the shotcrete liner in DART NC-1B tunnel showed cracking associated with water leaks. Considering the local geology and the history of the tunnel, researchers at The University of Texas at Arlington (UTA) suspected probable occurrence of …

Performance Studies On Rigid Pavement Sections Built On Stabilized Sulfate Soils, Deepti Vasudev

Civil Engineering Theses - Archive

Soils of Southeast Arlington are highly expansive and rich in sulfates. They undergo sulfate induced heaving when traditional calcium based stabilizers are used for soil stabilization (Puppala et al. 1998). Traditional stabilizers do not provide effective solution since they are known to induce heaving, termed in the literature as sulfate induced heaving (Hunter, 1988). Both swelling and softening of these soils rich in sulfates induce considerable damage to overlying pavement infrastructure. Typically, high sulfate soils treated with calcium based stabilizers form ettringite mineral. Ettringite undergoes heaving when hydrated (Hunter, 1988; Puppala et al. 2001). Since this sulfate-induced heave is caused …

Effects Of A Debonding Flaw Size And Location On The Flexural Performance Of Cfrp Retrofitted Steel Sections, Sharad C. Choudhary

Civil Engineering Theses - Archive

In US there are several thousand steel bridges at present. Out of them many bridges are at various level of advance deteriorations due to many years of service life and environmental factors. These bridges cannot be fully replaced so retrofitting is the best choice .Earlier steel plates were used. With introduction of FRP in 1960.It is replacing the steel plates as they are lighter in weight and can be made stronger than steel. While installation of these FRP some kinds of Flaws are encountered. The variation of strength of carbon fiber reinforced laminate used for structural repair or strengthening containing …

Evaluation Of Different Contra-Flow Strategies For Hurricane Evacuation In Charleston, South Carolina, Liz Stephen

All Theses

The number of category four and five hurricanes has nearly doubled over the past decade. Charleston, the second most populous city in South Carolina, is located on a very low peninsula, making it susceptible to floods during hurricanes and storm surges. In the event of a hurricane, the population at-risk must be evacuated to safety as quickly as possible. The Interstate system is the primary mode to evacuate at-risk population out of Charleston. Effective traffic management strategies are needed to manage the significant increase in demand on highways during the evacuation and contra-flowing traffic has been applied as a strategy …

Runway Incursion Mitigation, Capacity Enhancement, And Safety Improvements With Perimeter Taxiway Operations At Dallas Fort Worth International Airport, Satyamangalam D. Satyamurti

Civil Engineering Dissertations - Archive

A perimeter taxiway (PT) or end-around taxiway (EAT) operation is a new concept being developed at several airports around the country to eliminate active departure runway incursions during peak periods. PTs will enhance capacity by permitting uninterrupted, safe, continuous takeoffs and landings within the operations framework and guidelines established by the Federal Aviation Administration (FAA). For this research, the Dallas/Fort Worth International Airport's (DFW) proposed PT operations are considered for analysis and evaluation. This concept is tested using actual historical flight data at DFW for simulation and analytical modeling based on the FAA safety factors available in the Visual SIMMOD …

Permeability Of Municipal Solid Waste In Bioreactor Landfill With Degradation, Kiran Kumar Penmethsa

Civil Engineering Theses - Archive

Bioreactor landfills are operated and controlled to accelerate refuse decomposition, gas production and biological stabilization of the municipal solid waste (MSW). Leachate recirculation in bioreactor landfill creates a favorable environment for rapid microbial decomposition of the biodegradable components of solid waste. Therefore, clear understanding of the mechanism of moisture movement within the solid waste would be necessary for successful design and operation of the bioreactor landfill. Permeability is an important parameter during the design of leachate collection and recirculation system. In the current study an experimental program was designed to determine the variation of coefficient of permeability of MSW with …

Autotrophic Denitrification Of Groundwater In A Granular Sulfur-Packed Up-Flow Reactor, Shih-Hui Pan

Civil Engineering Dissertations - Archive

Autotrophic denitrification is an effective treatment technique for nitrate removal from groundwater. Six basic elements are required for the growth of autotrophic denitrifiers: (1) electron donor, (2) electron acceptor, (3) active bacteria, (4) anoxic/anaerobic environment, (5) micronutrients, and (6) optimum pH and temperature. In this research, granular sulfur is an electron donor; nitrate is an electron acceptor; anoxic and anaerobic environment was maintained in the reactor, and micronutrients were added; pH was controlled between 6 and 9, and temperature was maintained at the room temperature (20 + 2 oC). Batch reactor and continuous up-flow reactor experiments were carried out to …