Engineering Commons^™

Mechanical Properties And High-Temperature Performance Of A Polyester Resin Modified Using Fgd Gypsum, Morteza Janbaz

Theses and Dissertations

High-temperature performance of polyester- based construction materials is an important consideration when fire safety is a concern. These materials are typically used as non-structural components of buildings and other structures. Structural retrofits using fiber-reinforced polymer (FRP) composites are also gaining popularity. However, a major disadvantage of polymer- based materials (including FRP composites) is their flammability and toxic gas generation at high temperatures. The main objective of this research effort was to determine the mechanical properties and high-temperature performance of a polyester resin modified with various amounts of an industrial by-product additive. The additive used was Flu-Gas Desulfurization (FGD) gypsum, which …

Investigation Of Application Niche For Sustainable Wastewater Treatment Using Microbial Fuel Cells, Patrick Thomas Kelly

Theses and Dissertations

Microbial fuel cells represent a sustainable wastewater treatment technology due to its simultaneous treatment of contaminants and electricity production. Selection of suitable substrates is important to identifying proper application of microbial fuel cell (MFC) technology. In this work, four identical MFCs were used to treat the wastes sampled from different stages of a cheese wastewater treatment process, and both treatment performance and energy balance were examined. The two MFCs treating liquid wastes achieved more than 80% removal of total chemical oxygen demand (TCOD), while the other two MFCs fed with sludge or cheese whey removed about 60% of TCOD. The …

Sediment Microbial Fuel Cell As Sustainable Power Resource, Ananta Kothapalli

Theses and Dissertations

This research demonstrates that Ceratophyllum demersum a root less non vascular aquatic plant has negatively affected the power generation from a Sediment Microbial Fuel cell (SMFC). In SMFC the reduced organic matter in the sediment in water produces electrons, which reduces oxygen. Whereas in Plant SMFC continuous supply of organic matter to the anode is done by rhizodeposition (root exudates). Six SMFCs were run for more than 3 months to see the effect of plants, pH and temperature on power generation. Out of six only two SMFC showed stable data. The maximum power density 18 ± 1mW/m3 was generated from …

The Effectiveness Of Silane And Siloxane Treatments On The Superhydrophobicity And Icephobicity Of Concrete Surfaces, Sunil M. Rao

Theses and Dissertations

Icy roads lead to treacherous driving conditions in regions of the U.S., leading to over 450 fatalities per year. De-icing chemicals, such as road salt, leave much to be desired. In this report, commercially available silane, siloxane, and related materials were evaluated as solutions, simple emulsions, and complex emulsions with incorporated particulates, for their effectiveness as superhydrophobic treatments. Through the development and use of a basic impact test, the ease of ice removal (icephobicity) was examined as an application of the targeted superhydrophobicity.

A general correlation was found between icephobicity and hydrophobicity, with the amount of ice removed on impact …

Aqueous Turbulence Structure Immediately Adjacent To The Air - Water Interface And Interfacial Gas Exchange, Binbin Wang

Theses and Dissertations

Air-sea interaction and the interfacial exchange of gas across the air-water interface are of great importance in coupled atmospheric-oceanic environmental systems. Aqueous turbulence structure immediately adjacent to the air-water interface is the combined result of wind, surface waves, currents and other environmental forces and plays a key role in energy budgets, gas fluxes and hence the global climate system. However, the quantification of turbulence structure sufficiently close to the air-water interface is extremely difficult. The physical relationship between interfacial gas exchange and near surface turbulence remains insufficiently investigated. This dissertation aims to measure turbulence in situ in a complex environmental …

Travel Time In Macroscopic Traffic Models For Origin-Destination Estimation, Eric Youngblom

Theses and Dissertations

Transportation macroscopic modeling is a tool for analyzing and prioritizing future transportation improvements. Transportation modeling techniques continue to evolve with improvements to computer processing speeds and traffic data collection. These improvements allow transportation models to be calibrated to real life traffic conditions. The transportation models rely on an origin-destination (OD) matrix, which describes the quantity and distribution of trips in a transportation network. The trips defined by the OD matrix are assigned to the network through the process of traffic assignment. Traffic assignment relies on the travel time (cost) of roadways to replicate route choice of trips between OD trip …

A Rapid Construction Technique For Bridge Abutments Using Controlled Low Strength Materials (Clsm), Vahid Alizadeh

Theses and Dissertations

The required time for building bridge abutments is one of the key obstacles facing rapid bridge construction. For typical span bridges, this can be remedied by using Controlled Low Strength Materials (CLSM) as backfill materials placed behind full-height precast concrete panels that are integrated with the CLSM backfill via steel anchors. CLSM bridge abutments can be constructed in a short time as they do not require heavy machinery for excavation, compaction, and piling equipment. The main objective of this study was to examine the behavior of an instrumented laboratory large-scale CLSM bridge abutment with full-height precast concrete panels that was …

An Analysis Of Factors That Influence The Success Of Expeditionary Civil Engineer Hub-And-Spoke Organizations, Joshua A . Hager

Theses and Dissertations

Expeditionary Air Force Civil Engineer support to recent operations in southwest Asia created a unique organizational learning environment, particularly related supporting the general engineering requirements of geographically separated units in a manpower-constrained contingency environment. One of the direct results of this organizational learning was the hub-and-spoke expeditionary engineer unit featuring elements of both RED HORSE and Prime BEEF capabilities operating with theater-wide visibility of infrastructure requirements. This study acquired insights from literature and a purposeful sample of subject matter experts about operational advantages this hub-and-spoke unit offered compared to those offered by strictly legacy organizational models. The research used a …

Case Study Analysis Of Trust And Commitment Between The Civil Engineering Commodity Council And The Civil Engineering Career Field, Jonnathan B. Page

Theses and Dissertations

The Air Force is pursuing strategic sourcing as a strategy for reducing costs of goods and services to help meet budget reductions while still performing its mission. These commodities are sourced through a number of commodity councils, each of which whom interact with their stakeholders throughout the sourcing process for that specific commodity. This research identifies factors that influence the success or failure of the sourcing process from the perspective of the Civil Engineering Commodity Council (CECC) and attempts to organize these factors within a framework built around trust and its effect on commitment and cooperation. These factors were identified …