Engineering Commons^™

Direct Determination Of The Dynamic Elastic Modulus And Poisson's Ratio Of Timoshenko Prisms And Rods, Guadalupe Leon

Graduate Theses, Dissertations, and Problem Reports

In this study, the exact solution of the Timoshenko beam vibration frequency equation under free-free boundary conditions was determined with an accurate shear shape factor. The exact solution was compared with a 3-D finite element calculation using ABAQUS program, and the difference between the exact solution and the 3-D FEM was within 0.15% for both the transverse and torsional modes. Furthermore, relationships between the resonance frequencies and Poisson’s ratio were proposed that can directly determine the elastic constants, unlike the equations provided by ASTM C215. The frequency ratio between the 1^st bending mode and the 1^st torsional mode, …

Minimizing Trihalomethane Formation Through Source Water Monitoring And Optimizing Treatment Practices, Nashid Mirza

Graduate Theses, Dissertations, and Problem Reports

Trihalomethanes, a family of halogenated disinfection byproducts, are prevalent in finished drinking water. According to USEPA’s Disinfectants and Disinfection Byproducts Rules (DBPRs), the regulatory standard of the total trihalomethanes (TTHMs) is 80 μg/L, and water treatment plant operators are required to closely monitor TTHMs in the finished water on a quarterly basis. Although total organic carbon (TOC) has been identified as a precursor for the TTHMs, knowledge gaps still exist in how specific water and treatment related factors (e.g., intake water quality, seasonal variation, contact time, and treatment train) affect TTHMs formation. Focusing on water treatment plants in southwestern Pennsylvania, …

Review Of Water Allocation Models For West Virginia, Madison Lee Alexis Thompson

Graduate Theses, Dissertations, and Problem Reports

Modeling river basins started gaining in popularity and usage in the western part of the United States in large part due to its extreme droughts. Planning is necessary to sustain the population, industries, and recreational water use year-round. Water allocation modeling is a tool used to aid in the issues that come from managing water resources. This work considers the continuous models that synthesized the hydrologic processes that occur and provides a simulation of past, current, or future conditions.

West Virginia, located on the eastern side of the United States, does not have an extreme drought problem as seen in …

Numerical Modeling Of Hydraulic Fracture Propagation And Comparison With Microseismic Data At A Field Site, Carter Lawrence Hulcher

Graduate Theses, Dissertations, and Problem Reports

A hydraulic fracturing site in Morgantown, West Virginia, USA was selected to be a research site for the Marcellus Shale Energy and Environment Laboratory (MSEEL) project which was funded by the U.S. Department of Energy (DOE). The overall objective of the MSEEL research project is to evaluate and improve technologies to enhance shale gas recovery with minimal impacts on the environment. The field site has two previously drilled wells and two newly drilled wells for extracting natural gas. A separate exploratory well (or “science well”) was also drilled and includes a geophone array to extract important seismic/microseismic event information, which …

Structural Behavior Of Steel Plate Embedded Hybrid Gfrp Shapes, Piyush R. Soti

Graduate Theses, Dissertations, and Problem Reports

The civil infrastructure industry has been dominated by traditional materials such as steel, timber, and concrete. Although these materials offer great advantages, they have major durability issues in terms of corrosion, decaying, and cracking. Traditional material-based structures deteriorate frequently and require regular-interval repairs with huge expenditures. To resolve these maintenance and durability issues associated with traditional materials, fiber reinforced polymer (FRP) composites have gained some popularity in the past few decades because of their superior mechanical properties and durability. Carbon-FRPs (CFRPs) and glass-FRP (GFRPs) are the most commonly used FRPs in the market. However, in civil engineering applications, CFRPs are …

Short Beam Shear Strength Evaluations Of Gfrp Composites: Correlations Through Accelerated And Natural Aging, William Todd Barker

Graduate Theses, Dissertations, and Problem Reports

Fiber Reinforced Polymers (FRP) composites have been materials of interest in replacing or reinforcing steel, wood, and concrete, but lack of understanding of degradation under physical and chemical aging is a main concern. Through many years of research, the understanding of aging or durability of GFRPs has improved. To be able to evaluate aging related degradation rates, an accelerated aging methodology under varying environments is introduced. Accelerated aging is a concept used to age composites in a lab controlled environment under varying pH conditions (2 to 13) and temperatures (~ -20° to +160°F). Once acceleratedly aged testing is completed, Arrhenius …

Retaining Wall System With Soldier Pile And Composite Resin Infused Lagging Elements, Shane Phillip Moore

Graduate Theses, Dissertations, and Problem Reports

Retaining walls are used as an alternative to installing drainage and soil reinforcement, depending on site conditions. This report discusses the design of a retaining wall with steel soldier piles and lagging elements for rocky slopes. The design consists of six different options, three options with a span of eight feet and three options with a span of ten feet between soldier piles. The three options for both spans are the same concept but designed for different load conditions. These options include: timber with glass fiber reinforced polymers (GFRP) wraps, reinforced concrete with GFRP wraps, and an FRP Prodeck system …

Shear Stress Estimates In The Approach And Bridge Section By Using Various Formula, Jun Seon Lee

Graduate Theses, Dissertations, and Problem Reports

Shear stress is the resistance force on top of the contact surface caused by moving flow and is one of the important variable in fluid mechanics. Thus, a lot of researches have been conducted to predict accurate value of shear stress. However, calculating shear stress with existing equations has several limitations because only gradually varied flow and/or uniform flow was considered in their studies. Therefore, direct applying those methods into complex flow type, such as around a bridge, to predict shear stress is questionable.

Thus, laboratory experiments were carried out in a laboratory flume to attack the objective of this …

Evaluating Design Criteria For High Hazard Dams In A Changing Climate, Aaron Read Sutton

Graduate Theses, Dissertations, and Problem Reports

With changes in climate, there is the potential for future flooding events to vary in frequency and magnitude. These changes may stress the 432 high hazard dames in West Virginia. The 100-year flowrate is an important design criterion for emergency spillways of high hazard dams. Emergency spillways are designed to be reached only by 100-year flow and above. This work quantified how changes in the 100-year flowrate may affect emergency spillway activation. Peakflow data from the Central Appalachian Ecoregion in WV, taken from 24 USGS gages, were used to analyze changes in the 100-year flowrate.

Flow frequency analysis revealed that …

Bending Response Of Timber Mortise And Tenon Joints Reinforced With Filler-Modules And Frp Gussets, Andrew Robert Pacifico

Graduate Theses, Dissertations, and Problem Reports

In 2013, the California Bay Area (CBA) passed a set of ordinances to ensure that their 10,000 plus timber soft-story buildings were prepared for seismic events, through nondestructive evaluation methods. Many property owners are searching for an affordable retrofitting system that will also meet CBA’s new laws focusing on installations by the mandated deadlines in 2020. Over the past three to four decades, Fiber Reinforced Polymer (FRP) composites have found their way into the civil infrastructure sector for rehabilitation. The objective of this study is to evaluate the bending behavior retrofitted mortise and tenon timber joints reinforced with engineered wood …

Field Performance And Rating Evaluation Of A Modular Press-Brake-Formed Steel Tub Girder With A Steel Sandwich Plate Deck, Nicole Marie Hegele Underwood

Graduate Theses, Dissertations, and Problem Reports

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and culvert industry leaders (including steel manufacturers, fabricators, service centers, coaters, researchers, and representatives of related associations and government organizations) who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140 feet in length. The SSSBA technical working group has developed a shallow press-brake-formed tub girder, a trapezoidal cold bent girder, to address the demand in the short span steel bridge market for rapid infrastructure replacement solutions.

Following extensive experimental testing and design work at West …