http://www.archive.org/details/designofwatersys00adam Thesis (B.S.)--Armour Institute of Technolog; Includes folded leaves in back pocket ;... Show morehttp://www.archive.org/details/designofwatersys00adam Thesis (B.S.)--Armour Institute of Technolog; Includes folded leaves in back pocket ; Bibliography: leaf 1 Show less
http://www.archive.org/details/designofwatersup00shaw Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket... Show morehttp://www.archive.org/details/designofwatersup00shaw Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket Bibliography: leaf 1 Show less
A ground source heat pump system (GSHP) is a heating and air-conditioning system where a ground source is used as a heat source and sink.... Show moreA ground source heat pump system (GSHP) is a heating and air-conditioning system where a ground source is used as a heat source and sink. Potential ground sources include groundwater, surface water, and ground. A GSHP has several advantages over other heat pump systems, such as an air-source heat pump, because it has higher heating and cooling efficiency, more energy savings, and lower CO2 emissions. A treated wastewater source heat pump (TWSHP) system is similar to a GSHP system, but the TWSHP system relies on a treated wastewater source, which means that the source temperature is variable. A TWSHP is more convenient and offers greater cost savings; the TWSHP system avoids the costs associated with pumping, grouting, and drilling because the treated wastewater is already available at the surface. RETScreen is a software product that provides a methodology to study the feasibility of installing a constant-temperature source GSHP system. Advantages of using RETScreen include it is tested, valuable, readily available, and free. If design of a variable-temperature source TWSHP system can take advantage of RETSceen methodology, it would bring a tremendous help for TWSHP applications. This paper presents a case study to test whether a TWSHP system can take advantage of RETSceen methodology. The approach involves an assessment of TWSHP system operating performance under variable source temperatures. Results show that a TWSHP system can take advantage of RETSceen methodology for a variable source temperatures span over a certain range. In this study the heating temperature ranged from 9 to 16 ℃ and the cooling temperature ranged from 11 to 22℃. Keywords: treated wastewater source heat pump; RETScreen methodology M.S. in Environmental Engineering, July 2013 Show less
Masonry arch bridges are regarded as the oldest examples of engineered structures in the world; and they reflect the previous civilizations in... Show moreMasonry arch bridges are regarded as the oldest examples of engineered structures in the world; and they reflect the previous civilizations in the world with their various sizes, styles, and spans. The preservation of these structures is receiving a great deal of attention in the structural engineering community. And as such, restoration, strengthening and reinforcement of historical masonry bridges have become a challenge for civil engineers. At the present time, most important problems of masonry arch bridges are heavy traffic loads and destructive natural disasters. These bridges were constructed centuries ago and they addressed the load-carrying problems of old times. With the passing of the time, the traffic changed and many natural disasters occurred. Correspondingly, loads on masonry arch bridges have increased and the traffic on the bridges have become more intense in the course of time. However, the bridges keep up to their initial performance; and this shows the complexity of their structural behaviors. This study provides the background information about masonry arch bridges and their components. It also helps us better understand the construction materials, structural properties and structural behavior of masonry arch bridges. In light of this background information, this study presents an overview of seismic retrofit for masonry arch bridges and a comprehensive study on the type, mechanism of failure and structural integrity of masonry arch bridges. M.S. in Civil Engineering, July 2011 Show less
Trusses, although geometrically simple, constitute rather complex structures when one considers their true behavior. Even though they are... Show moreTrusses, although geometrically simple, constitute rather complex structures when one considers their true behavior. Even though they are designed considering pin connections for their joints, in practice joints are neither pinned nor fixed. For this reason, the behavior of a truss at its joints is rather complicated; and to a great extent depends on the method of fabrication used including the weld patterns and the geometry and design of gusset plates used. This study focuses on the behavior of welded truss joints by using a three-dimensional finite element analysis in an effort to provide an insight into how stress patterns are developed at a joint when it is subject to loads from adjoining truss members. The research included a series of simulation analyses on a simple truss joint with welded connections. The typical joint is those that can be found in the lower chords of trusses used in highway bridges. The simulations employed linear finite element analyses utilizing solid elements to model the weld, connecting elements and the gusset plates. Stresses obtained from these analyses were compared with those through conventional methods. At points of stress concentrations, stresses from the finite element (FE) analyses showed stresses can be as high as 5 – 10 orders of magnitude higher than those from conventional methods. The results are presented in the form of graphs showing the ratio of FE-based results to those from conventional methods for several different configurations for weld length. M.S. in Civil Engineering, December 2011 Show less