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Theses and Dissertations

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Full-Text Articles in Civil and Environmental Engineering

A New Global Forecasting Model To Produce High-Resolution Stream Forecasts, Alan Dee Snow Apr 2015

A New Global Forecasting Model To Produce High-Resolution Stream Forecasts, Alan Dee Snow

Theses and Dissertations

Warning systems with the ability to predict floods days in advance can benefit tens of millions of people. Because of these potential impacts there have been efforts to improve prediction systems such as the United States’ Advanced Hydrologic Prediction Service and European-developed Global Flood Awareness System. However, these projects are currently limited to relatively coarse resolutions. This thesis presents a method for downscaling and routing global runoff forecasts generated by the European Centre for Medium-Range Weather Forecasts using the Routing Application for Parallel computatIon of Discharge program that make possible orders of magnitude increases in the density of the resolution …

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Organizational Learning In Commercial Construction: Lessons Learned From The 2007-2009 U.S. Recession, Evan Michael Danforth Apr 2015

Organizational Learning In Commercial Construction: Lessons Learned From The 2007-2009 U.S. Recession, Evan Michael Danforth

Theses and Dissertations

Organizational learning seeks to proactively expand the knowledge base of an organizational entity by incorporating knowledge, skills, and experience into the collective conscience of the company through the development of routines rather than relying on individual employees for these traits. Valuable experience gained by individuals who weather economic downturn with their companies must be absorbed into the corporate structure in a meaningful way so that it may be accessible for use during future recessions. This research asks what was learned by individuals during the most recent recession, what mechanisms were employed to retain and utilize this knowledge, and what cultures, …

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Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings Mar 2015

Detection And Characterization Of Malathion Adherence To Piping Materials Used In Water Distribution Systems, William D. Flemings

Theses and Dissertations

Protection of the public water supply is a national security priority, and as such, it is important to better understand the fate of a chemical weapons agent injection into a public water distribution system. This study investigated the adherence of malathion to pipe materials that are used in public water distribution systems, with malathion serving as a chemical representative of the organophosphorus nerve agent VX. Copper and iron specimen were exposed to malathion solutions for periods of 4, 8, and 24 hours and then tested for evidence of chemical adherence to the metal surfaces. Nonlinear desiccation profiles revealed total mass …

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Integrating Pavement Crack Detection And Analysis Using Autonomous Unmanned Aerial Vehicle Imagery, Patrick J. Grandsaert Mar 2015

Integrating Pavement Crack Detection And Analysis Using Autonomous Unmanned Aerial Vehicle Imagery, Patrick J. Grandsaert

Theses and Dissertations

Efficient, reliable data is necessary to make informed decisions on how to best manage aging road assets. This research explores a new method to automate the collection, processing, and analysis of transportation networks using Unmanned Aerial Vehicles and Computer Vision technology. While there are current methodologies to accomplish road assessment manually and semi-autonomously, this research is a proof of concept to obtain the road assessment faster and cheaper with a vision for little to no human interaction required. This research evaluates the strengths of applying UAV technology to pavement assessments and identifies where further work is needed. Furthermore, it validates …

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Analysis Of Air Force Wartime Contracted Construction Project Performance, Ryan M. Hoff Mar 2015

Analysis Of Air Force Wartime Contracted Construction Project Performance, Ryan M. Hoff

Theses and Dissertations

Using a dataset of 25 Afghan wartime projects, two questions were investigated: 1) What factors affect the success of construction projects; and 2) How do project outcomes differ based on the contract type? Current literature suggests that wartime projects may face the same cost and schedule factors as peacetime projects, with some notable additions. Project factors, health and safety compliance, quality of work, technical performance, work productivity, and external environmental factors were tested with contingency tables to determine dependency with schedule or cost performance. External environmental factors, including weather and wartime security, were not predictive of project performance. However, cost …

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Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi Mar 2015

Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi

Theses and Dissertations

A study was conducted to evaluate the advanced oxidation of organic contaminants using pulsed ultraviolet light emitted diode (UV LED). Tartrazine was used as a surrogate organic compound. Low pressure Mercury-based lamps currently used in the treatment of water pose potential health risks if broken and create final disposal issues at the end of their service life. UV LED offers an alternative solution due to its non-toxicity, flexible design, and longer operating life compared to the mercury-based lamps. The apparent first order reaction rate constant for tartrazine degradation increased linearly with increasing duty cycle. At a continuous 100% duty cycle, …

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The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee Mar 2015

The Fate Of Malathion On Copper And Iron Piping Within A Water Distribution System, Walter R. Lee

Theses and Dissertations

Thermogravimetry, the study of mass loss as a function of temperature, has been used for oxidation, decomposition, and solid-state studies. This research used a thermogravimetric analyzer (TGA) coupled with Fourier transform infrared (FT-IR) spectroscopy in the study of copper and iron specimens exposed to malathion. Exposure to the malathion solution created a visible silver coating on copper and graphite-flake particles on iron specimens. Thermogravimetric mass loss curves revealed linear and nonlinear decomposition stages associated with mass loss reactions. Copper specimens exposed to malathion exhibited lower activation energy (Ea) values (2.28 to 4.40 kJ mol-1) than for copper specimens exposed to …

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The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas Mar 2015

The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas

Theses and Dissertations

Decontamination activities following a chemical weapons incident may generate significant quantities of contaminated wash water that may enter the wastewater collection system either intentionally or accidentally. This raises concerns about the effect of chemical warfare agents (CWAs) on the operation of a biological wastewater treatment plant. The goal of the study was to evaluate the effect of malathion on the activity and performance of activated sludge. Malathion is an organophosphate (OP) and is considered an environmental surrogate for VX. This study employed respirometry, short term batch tests, and long term exposure experiments to investigate the effects of different concentrations of …

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A Probabilistic Assessment Of Failure For Air Force Building Systems, Stephanie L. Alley Mar 2015

A Probabilistic Assessment Of Failure For Air Force Building Systems, Stephanie L. Alley

Theses and Dissertations

Deteriorating and failing federal facilities represent a cost to leaders and organizations as they attempt to manage and maintain these assets. Currently the Air Force employs the BUILDERTM Sustainment Management System to predict the reliability of building components. At different system levels, however, the probabilities of failure are not predicted. The purpose of this research is to provide probabilistic models which predict the probability of failure at the system level of a building s infrastructure hierarchy. This research investigated the plumbing, HVAC, fire protection, and electrical systems. Probabilistic models were created for these systems by using fault trees with …

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Test And Evaluation Of Ultrasonic Additive Manufacturing (Uam) For A Large Aircraft Maintenance Shelter (Lams) Baseplate, Daniel H. Gartland Mar 2015

Test And Evaluation Of Ultrasonic Additive Manufacturing (Uam) For A Large Aircraft Maintenance Shelter (Lams) Baseplate, Daniel H. Gartland

Theses and Dissertations

Additive manufacturing is an exciting new manufacturing technology that could have application to Air Force Civil Engineer (CE) operations. This research replicates a Large Area Maintenance Shelter (LAMS) baseplate design for ultrasonic additive manufacturing (UAM). Due to production problems the test section was not built as designed. Instead, a smaller block of material was submitted for evaluation. After the UAM build, ultrasonic inspection was conducted to identify anomalies in the test piece. The results of this proof of concept study indicate that UAM is not yet ready for CE expeditionary applications requiring a high degree of mechanical strength. The machine …

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The Impact Of United States Investment For Civil Infrastructure In Developing Countries, Joel N. Hansen Mar 2015

The Impact Of United States Investment For Civil Infrastructure In Developing Countries, Joel N. Hansen

Theses and Dissertations

U.S. foreign assistance is used to support regional interests and to address the economic and social needs of host nation (HN) citizens. Within the Department of Defense (DoD), military exercises implement humanitarian and civic assistance (HCA) activities in developing nations as one method of accomplishing the U.S. foreign assistance objectives. To account for the impact of civil infrastructure projects on HN citizens, this research incorporated survey data collected during a DoD-sponsored exercise in Belize to test the expectancy disconfirmation model of citizen satisfaction and analyze the impact of constructing HCA projects on citizen satisfaction with HN government services. The research …

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Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin Mar 2015

Effect Of Malathion On The Microbial Ecology Of Activated Sludge, Seth K. Martin

Theses and Dissertations

Decontamination activities may cause the release of contaminated washwater into the wastewater that eventually flows into a wastewater treatment facility. This raises concerns about the effect of chemical warfare agents (CWAs) on the microbial consortia that are responsible for cleaning the wastewater. This study investigated the impact of malathion on the microbial ecology of laboratory scale activated sludge communities. The Simpson Reciprocal Index decreased for three bioreactors operated in the absence of malathion, which showed that the microbial assemblage became less diverse during the course of the study. The species identified in the bioreactors belonged to well-known groups of heterotrophic …

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Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara Mar 2015

Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara

Theses and Dissertations

The goal of this study is to use Modeling and Simulation of Evacuation Plan (MSEP) to support management to execute proper evacuation plan in case of emergency at Hancock Stadium in Illinois State University. Analyses of the research literature and evacuation scenarios are used to build a simulation system that will connect a description of emergency and evacuation situation with its context. It shows how an evacuation plan actually functions. The results of the study will help safety managers to understand the current situations of evacuation according to the specific simulation scenarios. The evacuation simulation is categorized according to the …

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Event-Based Hydrologic Model Calibration Using Nexrad In A Data-Poor Region Of Southern New Jersey, Christopher Siegel Mar 2015

Event-Based Hydrologic Model Calibration Using Nexrad In A Data-Poor Region Of Southern New Jersey, Christopher Siegel

Theses and Dissertations

Proper calibration of hydrologic models requires both reliable observed stream flow and precipitation data. Southern New Jersey has a notable lack of observed precipitation data, in particular, at the event scale; therefore model calibration represents a significant challenge. From a design standpoint this has not been a major concern as hydrologic models have been driven using design storms and are not calibrated. However, the need for research and impact analyses in the face of climate change (changes in extreme precipitation and sea-level rise in particular) and expected population growth in the region requires calibrated models, and reliable observed precipitation data …

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Verification Of The Dissipated Energy Based Fatigue Model Using Field Data, Thomas Redles Mar 2015

Verification Of The Dissipated Energy Based Fatigue Model Using Field Data, Thomas Redles

Theses and Dissertations

Damage can be limited to the top layer in perpetual pavements through the use of a very thick surface layer or a binder-rich intermediate layer. To achieve this goal, tensile strains at the bottom of the top hot-mix asphalt (HMA) layer must be limited to below a certain value known as the fatigue endurance limit (FEL). In this thesis, a method for estimating the allowable strain in the asphalt layers of flexible airfield pavements is proposed based on the concept that HMA fatigue failure is associated with a significant reduction in HMA layer modulus, usually taken as 50 percent. Falling …

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Hydrologic Data Sharing Using Open Source Software And Low-Cost Electronics, Jeffrey Michael Sadler Mar 2015

Hydrologic Data Sharing Using Open Source Software And Low-Cost Electronics, Jeffrey Michael Sadler

Theses and Dissertations

While it is generally accepted that environmental data are critical to understanding environmental phenomena, there are yet improvements to be made in their consistent collection, curation, and sharing. This thesis describes two research efforts to improve two different aspects of hydrologic data collection and management. First described is a recipe for the design, development, and deployment of a low-cost environmental data logging and transmission system for environmental sensors and its connection to an open source data-sharing network. The hardware is built using several low-cost, open-source, mass-produced components. The system automatically ingests data into HydroServer, a standards-based server in the open …

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Investigation Of Laboratory Test Procedures For Assessing The Structural Capacity Of Geogrid-Reinforced Aggregate Base Materials, Jaren Tolman Knighton Mar 2015

Investigation Of Laboratory Test Procedures For Assessing The Structural Capacity Of Geogrid-Reinforced Aggregate Base Materials, Jaren Tolman Knighton

Theses and Dissertations

The modulus of aggregate base layers in pavement structures can potentially be increased through the use of geogrid. However, methods for determining how much structural benefit can be expected from a given geogrid product have not been standardized. A laboratory testing protocol is therefore needed to enable evaluation, in terms of modulus or California bearing ratio (CBR), for example, of the degree of improvement that may be achieved by a given geogrid. Consequently, the objective of this research was to identify a laboratory test method that can be used to quantify improvements in structural capacity of aggregate base materials reinforced …

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Modeling Stokes Flow Using Hierarchical Structure-Preserving B-Splines, Kendrick Monroe Shepherd Mar 2015

Modeling Stokes Flow Using Hierarchical Structure-Preserving B-Splines, Kendrick Monroe Shepherd

Theses and Dissertations

A new spline space, the hierarchical structure-preserving B-spline space, is introduced and implemented in the analysis of Stokes flow. The space, when properly constrained, is shown to be stable and to have at least optimal convergence rates in the velocity field and suboptimal convergence rates in the pressure field. However, results show that superoptimal convergence can often be expected in the pressure field, likely due to error reduction in the velocity field. Like other hierarchical spline spaces, these splines are shown to greatly increase accuracy and to drastically lower computation times for analyses on domains whose solution fields have singularities …

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Using Remote Sensing To Explore The Time History Of Emergent Vegetation At Malheur Lake, Oregon, Zola Yaa Adjei Mar 2015

Using Remote Sensing To Explore The Time History Of Emergent Vegetation At Malheur Lake, Oregon, Zola Yaa Adjei

Theses and Dissertations

The growth patterns of emergent vegetation can be a useful indicator for factors affecting lake health. However, field data to characterize emergent vegetation at many reservoirs may not be available or may be limited to small, isolated areas. We present a case study using remotely sensed data from the Landsat satellite to generate data to represent emergent vegetation in the near-shoreline and tributary delta areas of Malheur Lake, Oregon. We selected late June images for this study as vegetation is relatively mature in late June and visible, but has not completely grown-in providing a better indication of vegetation coverage in …

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Shear Strength Prediction Methods For Grouted Masonry Shear Walls, Patrick Dillon Mar 2015

Shear Strength Prediction Methods For Grouted Masonry Shear Walls, Patrick Dillon

Theses and Dissertations

The research in this dissertation is divided between three different approaches for predicting the shear strength of reinforcement masonry shear walls. Each approach provides increasing accuracy and precision in predicting the shear strength of masonry walls. The three approaches were developed or validated using data from 353 wall tests that have been conducted over the past half century. The data were collected, scrutinized, and synthesized using principles of meta-analysis. Predictions made with current Masonry Standards Joint Committee (MSJC) shear strength equation are unconservative and show a higher degree of variation for partially-grouted walls. The first approach modifies the existing MSJC …

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Reducing Drifts In Buckling Restrained Braced Framesthrough Elastic Stories, Jennifer Lorraine Craft Mar 2015

Reducing Drifts In Buckling Restrained Braced Framesthrough Elastic Stories, Jennifer Lorraine Craft

Theses and Dissertations

It is possible to reduce residual and maximum drifts in buildings by adding “elastic stories” that engage gravity columns in seismic response. An elastic story is a story wherein the buckling restrained brace frame (BRBF) size is increased to prevent yielding when an earthquake occurs. Buildings ranging from 4–16 stories were designed with various elastic story brace sizes and locations to determine the optimal combination to best reduce drifts. Gravity column stiffnesses were also varied in elastic story buildings to determine the effects on drifts. Computer models were used to analyze these buildings under a suite of earthquakes. Adding elastic …

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Experimental Testing Of Shallow Embedded Connections Between Steel Columns And Concrete Footings, Nicholas Valgardson Barnwell Mar 2015

Experimental Testing Of Shallow Embedded Connections Between Steel Columns And Concrete Footings, Nicholas Valgardson Barnwell

Theses and Dissertations

Shallow embedded column connections are widely used for columns resisting gravity loads in current design methods. These connections are usually considered “pinned” for structural analysis. In reality these connections fall in between a fixed and a pinned condition. Although methods exist to estimate the stiffness and strength of exposed columns or embedded columns under lateral loads, little research has been done to determine the strength of shallow embedded columns. An experimental study was carried out to investigate the strength of these connections. A total of 12 specimens with varying orientation, embedment depth, and column size were loaded laterally until failure …

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Development Of Computer Simulation Model For Urban Region Using Xp-Swmm In Savannah, Georgia, Matthew Dale Ricks Jan 2015

Development Of Computer Simulation Model For Urban Region Using Xp-Swmm In Savannah, Georgia, Matthew Dale Ricks

Theses and Dissertations

The objective of this thesis was to determine if it is possible to create, calibrate, and validate a computer simulation model given a limited amount of measured data. In June 1999, significant flooding was experienced throughout the Casey Canal North drainage basin in Savannah, Georgia. Time-depth rainfall data from a single gage was recorded for this event, along with peak water surface elevations throughout the basin. The computer model chosen for this application was XP-SWMM, which was approved by the Federal Emergency Management Agency to simulate both one dimensional and two dimensional hydraulic models. XP-SWMM was chosen due to its …

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Adaptivity For Meshfree Point Collocation Methods In Linear Elastic Solid Mechanics, Joshua Wayne Derrick Jan 2015

Adaptivity For Meshfree Point Collocation Methods In Linear Elastic Solid Mechanics, Joshua Wayne Derrick

Theses and Dissertations

This study presents the behavior of local node adaptivity for point collocation meshfree numerical methods and its application to linear elastic solid mechanics. A bisection approach to meshfree adaptivity will be presented with numerical examples showing that convergence is achieved. A threshold value is required from the user and this value is an acceptable change in gradient for the problem. If the change in gradient between 2 nodes exceed this limit, a node is added at the mid-point between the two nodes. This process applies to all nodes in the model. Once the refinement is complete, the model is processed …

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Experimental Study Of Longitudinal Sorting Of Particles Differing In Size And Density, Nabila Mahjabeen Jan 2015

Experimental Study Of Longitudinal Sorting Of Particles Differing In Size And Density, Nabila Mahjabeen

Theses and Dissertations

Transport, deposition and erosion of sediment particles differing in size, shape and density may result in particle segregation, which in geosciences applications is generally referred to as sediment sorting. A thorough understanding of sediment sorting processes is important to describe and model a wide variety of natural processes such as the decrease in particle size and/or density in a fluvial system (downstream fining and/or lightening), the formation of economic placers, concentration of heavy minerals, chemical and metal pollutants etc. Sorting of sediment grains associated with sediment transport in the streamwise direction results in the development of longitudinal sorting patterns. Vertical …

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Drilled Shaft Skin Resistance Design In The Cooper Marl, William J. Gieser Jan 2015

Drilled Shaft Skin Resistance Design In The Cooper Marl, William J. Gieser

Theses and Dissertations

As drilled shafts have become a more popular foundation type in the Charleston, South Carolina area, there has been an ongoing goal of optimizing drilled shaft design while maintaining the structural integrity of the foundation. In the Charleston area, the primary bearing stratum for deep foundations is the Cooper Marl, a calcareous Oligocene formation. Research performed from 2002 to 2004 on load test data from drilled shafts constructed in the Cooper Marl and soil properties from three test sites for the Cooper River Bridge explored the relationship between the measured skin resistance and geotechnical properties. In the 15 years since …

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Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh Jan 2015

Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh

Theses and Dissertations

The goal of this study is to further advance the state of the art in developing self-sufficient methods to predict the performance of an aerosol filter. The simulation methods developed in this study are based on first principles and consequently, they do not rely on empirical correction factors. These simulation methods can be used to predict the instantaneous collection efficiency and pressure drop of a filter under dust-loading conditions. In the current study, 3-D micro- and macroscale CFD models are developed to simulate the service life of flat-sheet and pleated filters. These CFD micro- and macroscale models are also used …

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Functionalized Graphitic Nanoreinforcement For Cement Composites, Nima Zohhadi Dec 2014

Functionalized Graphitic Nanoreinforcement For Cement Composites, Nima Zohhadi

Theses and Dissertations

Physical and mechanical properties of graphitic nanomaterials, in particular multiwalled carbon nanotubes (MWCNTs) and graphene nano-platelets (GNPs) make them promising candidates for nanoreinforcement of cement composites. The two key challenges associated with the incorporation of MWCNTs and GNPs are to attain uniform dispersion and interfacial bonding within the composite matrix. The effects of three main-stream dispersion techniques (namely, ultrasonication, acid-etching, and surfactant-coating) on the mechanical properties and microstructure of MWCNT- and GNP-cement composites were experimentally studied. Compressive strength tests and different characterization techniques including dynamic light scattering, Raman spectroscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission …

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Application Of Various Adsorbents To Remove Micro-Pollutants In Aquatic System, Chanil Jung Dec 2014

Application Of Various Adsorbents To Remove Micro-Pollutants In Aquatic System, Chanil Jung

Theses and Dissertations

Untreated or insufficiently treated pharmaceuticals and endocrine disrupting compounds (EDCs) as well as heavy metals have influenced the ecosystem and their exposures in the water system have threatened human health; causing cancers and adverse health effect to immune system. While various water treatment techniques have been applied to solve this problem, adsorption has been considered as one of the most efficient and manageable water purification techniques. Advanced analysis methods for aqueous contaminants have improved comprehension, allowing proficiency about the fate of trace leveled emerging contaminants, thus allowed to reveal the adsorption mechanisms of each pollutant. This dissertation focuses on the …

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Context-Sensitive Seismic Strengthening And Repair Of Substandard Confined Masonry, Rahim Ghorbani Dec 2014

Context-Sensitive Seismic Strengthening And Repair Of Substandard Confined Masonry, Rahim Ghorbani

Theses and Dissertations

Confined masonry (CM) is a construction system consisting of load-bearing masonry panels that are confined with cast-in-place reinforced concrete tie columns and beams. Due to satisfactory seismic performance, CM has become the predominant low-rise residential construction system in several areas around the world. However, in developing regions, the use of substandard materials, details and construction practices may result in inadequate performance as highlighted in the 2010 earthquakes in Haiti and Chile. In the aftermath of an earthquake, households are often reluctant to reoccupy their dwellings due to concerns about safety of structures. If feasible, preventive (pre-hazard) strengthening or structural repair …

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