Engineering Commons^™

Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang

USF Tampa Graduate Theses and Dissertations

Automated prediction of runway configuration and airport capacity is critical for the future generation of air traffic management. In the future aviation industry, multi-sources weather forecast information will be available for air traffic decision-making units; how to use these data efficiently is key for overall efficiency of air traffic management. Currently, air traffic management personnel lack tools to assist them to translate weather forecast data into real-time airport capacity. Runway configurations and AARs of airports in a multi-airport system are determined by different air traffic controller personnel. The lack of synchronization may lead to the loss of efficiency of the …

Enhancing Concrete Pavement Service Life Using Multiple Strategies To Reduce Cracking Potential, Dhanushika Mapa Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Over the past years, prevention of cracking in concrete structures, especially at early age, has been a challenge facing transportation agencies. During early age, restraint of thermal and moisture related volume changes causes cracking in concrete. This research focuses on evaluating the effectiveness of different cracking mitigation strategies that can be implemented, in different concrete elements, to reduce early-age cracking incidents and therefore enhance concrete service life. To this end, a battery of field and laboratory testing were conducted, and finite element analysis was performed to better understand the mechanisms of primary significance on minimizing cracking risks commonly associated with …

Thermo-Oxidative Degradation Of Hdpe Geomembranes: Effect Of Phenolic Antioxidant And Hindered Amine Light Stabilizer Concentrations, Yasin Kocak

USF Tampa Graduate Theses and Dissertations

High density polyethylene (HDPE) geomembrane is most common geomembrane which is mainly used for civil engineering applications. However, HDPE geomembrane loses its properties under oxidative degradation progress. This study aims to assess geomembranes which have different percentage of phenolic antioxidant and hindered amine light stabilizer (HALS) with under the six months of the thermal-oxidative degradation. The interactions between phenolic antioxidant, HALS and carbon black can affect the mechanical, physical and chemical properties. To monitor these properties, Differential Scanning Calorimetry (DSC), Fourier-transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy (SEM/EDX), Melt Index tests, …

Impact Of The Number Of Lane-Changing Times On Throughput By Fundamental Diagram Based On Ngsim Data, Gangyan Zhang

USF Tampa Graduate Theses and Dissertations

In the present report, the characteristics of the fundamental diagram (FD) are exploited to delve into the effect of the number of times of lane changes on traffic throughput. The NGSIM data are classified and screened by splitting the regions of US-101 and I-80; the relevant traffic variables (e.g., traffic flow, density and speed) are calculated. Appropriate statistical approaches are employed to verify the correlation of the impact of lane changes on different traffic variables. Lane changes could affect traffic throughput in light congestion instead of in heavy congestion. The causes of the effects of lane changes on throughput are …

Device For Imaging Cross-Section Of Post-Tensioned Structural Tendons In The Field, David Dukeman

USF Tampa Graduate Theses and Dissertations

With increasing use of grouted post-tensioned tendons in structures, there is a critical need for equipment to determine deficient grouting. Inadequate grouting can cause dangerous corrosion of the high-strength post-tensioning steel in the tendons. Evaluation should be non-destructive, and early detection is needed to take timely remedial actions to repair or replace any tendons that are affected before catastrophic failure occurs. In particular, there is need for an imaging method that shows the cross-section of the tendon being tested and flag any deficiencies present relative to the location of the strands in the cross section. The method should be rapid, …

Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas

USF Tampa Graduate Theses and Dissertations

With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing, baskets …

Effects Of Support Fluid Type On Concrete Integrity And Durability In Drilled Shafts, Sarah J. Mobley

USF Tampa Graduate Theses and Dissertations

Until recently, concrete flow in tremie-placed drilled shafts has been mischaracterized as rising uniformly with laitance formation occurring only at the top of the rising concrete in the shaft. In actuality, concrete first fills a portion of the reinforcement cage to a sufficient height to promote radial flow into the cover region. Depending on support fluid type, the radial flow can produce laitance-filled creases/channels projecting the reinforcing cage configuration to the side of shaft surface. The flow pattern (and creases) can affect filter cake thickness, cover quality and propensity for corrosion. This research examines 52 tremie-placed laboratory drilled shaft specimens …

Morphology And Detection Of Corrosion On Stainless Steel Reinforcement In Concrete, Julio J. Saire Yanez

USF Tampa Graduate Theses and Dissertations

Stainless steel (SS) has emerged as an alternative corrosion-resistant reinforcement in concrete instead of the commonly used carbon steel (CS). The biggest advantage of SS is that it takes more time for corrosion to initiate than for CS. An additional benefit from the use of SS in concrete may be derived from the period after the corrosion started until the concrete structure reaches a limit state. This period is called corrosion propagation stage (CPS) and it has been hardly studied in SS reinforced structures. The duration of this period could be related, among other factors, to the morphology of corrosion …

Prioritizing Rehabilitation Of Sanitary Sewers In Pinellas County, Fl, Jesse T. Hillman

USF Tampa Graduate Theses and Dissertations

Following large rain events, extraneous freshwater contributions known as inflow and infiltration (I/I) bypass the storm sewer and enter the sanitary sewer system. In areas with a high water table, like Pinellas County and the surrounding Tampa Bay area, a majority of the wastewater infrastructure is submerged year round exacerbating the rate of groundwater infiltration. This excess flow overloads the existing wastewater infrastructure leading to sanitary sewer overflows (SSOs). These SSOs result in serious problems for municipalities and utilities across the country.

This study was performed in order to assist Pinellas County Utilities in rehabilitating their southern sewer system. To …

Steady State Hydroplaning Risk Analysis And Evaluation Of Unsteady State Effects, Menna Yassin

USF Tampa Graduate Theses and Dissertations

Hydroplaning is a major concern on high speed roadways during heavy rainfall events. Hydroplaning tools are widely used by designers to reduce their roadway’s hydroplaning potential, therefore reducing the possibilities of severe crashes. This dissertation presents two methodologies for improving the prediction of hydroplaning potential.

The first phase focused on improving an existing widely used software called PAVDRN. Using multiple datasets from the Florida Department of Transportation, the author filtered the data using specific criteria to leave only truly dynamic hydroplaning crashes. The author then evaluated PAVDRN’s prediction capabilities and assessed its reliability in predicting a hydroplaning crash. Using past …

Characterization Of Geogrid Reinforced Ballast Behavior Through Finite Element Modeling, Bugra Sinmez

USF Tampa Graduate Theses and Dissertations

Recently, the railway pavement structure system, as an integral part of the transport infrastructure, has been under fast development in some countries such as China, Turkey, and some European Union countries, particularly for the use of high-speed trains. In designing and constructing the railway pavement structure, it is necessary to take into account the infrastructure demand of the High-Speed Railway Lines (HSRL). Compared to traditional railway trains, HSRL can cause more significant problems to the ballast or base layer of commonly used ballasted railway pavements. The deteriorated ballast or base layer may further result in substructure degradation that may cause …

Seepage-Coupled Finite Element Analysis Of Stress Driven Rock Slope Failures For Bothnatural And Induced Failures, Thomas Becket Anyintuo

USF Tampa Graduate Theses and Dissertations

Rock slope failures leading to rock falls and rock slides are caused by a multitude of factors, including seismic activity, weathering, frost wedging, groundwater and thermal stressing. Although these causes are generally attributed as separate causes, some of them will often act together to cause rock slope failures. In this work, two of the above factors, seepage of water through cracks and crack propagation due to the after effects of blasting are considered. Their combined impact on the development of rock falls and rock slides is modeled on ANSYS workbench using the Bingham Canyon mine slope failure of 2013 as …

Evaluation Of Strand To Grout Bond In Post-Tensioned Tendons With Corrosion Inhibiting Penetrants, Kurt Kupselaitis

USF Tampa Graduate Theses and Dissertations

Post tensioning bridges is an efficient way of construction where segments of a bridge are strung together using small diameter high strength strands. The steel strands are passed through internal and/or external ducts within the concrete segments, jacked to high levels of stress, anchored using steel wedges, and then filled with a corrosion inhibiting filler. A cementitious material called grout has been widely used for over 50 years as this filler. The Federal Highway Administration design and construction manual provides recommendations in the properly filling techniques to ensure the tendons are full of grout. Despite the level of detail the …