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Full-Text Articles in Civil and Environmental Engineering

Color Removal From Pulp Mill Effluent Using Coal Ash Produced From Georgia Power Coal Combustion Plants, Christopher B. Willett Jan 2015

Color Removal From Pulp Mill Effluent Using Coal Ash Produced From Georgia Power Coal Combustion Plants, Christopher B. Willett

College of Graduate Studies: Theses & Dissertations

Two environmental concerns currently face Georgia: coal fly ash (CFA) waste from coal power plants, and the effluent generated by pulp mills. Pulp mill effluent discolors surface waters into which it is discharged, and has been proven to negatively impact the dissolved oxygen and carbon necessary for aquatic life. The proposed solution is a cost-effective adsorption treatment using an inexpensive but abundantly available waste material: CFA. CFA possesses beneficial properties that allow it to effectively remove contaminants, and is available at significantly reduced cost. The primary research objective was to define treatment parameters that would result in the maximum removal …


Moisture Susceptibility Of Dense Graded Asphalt Concrete Using Cyclic Moistue Induced Stress Tester, Sarvesh Dip Dhakal Jan 2015

Moisture Susceptibility Of Dense Graded Asphalt Concrete Using Cyclic Moistue Induced Stress Tester, Sarvesh Dip Dhakal

Open Access Theses & Dissertations

Moisture damage in asphalt concrete causes loss in mechanical properties of asphalt material due to the presence of moisture in its microstructures in a liquid or a vapor state. Some of the common types of distress observed in asphalt pavements due to moisture damage are stripping (separation of asphalt binder and aggregate), raveling (dislodgement of aggregate particles in asphalt mixture from surface), and hydraulic scour (a process that occurs on a saturated surface by which the pavement material is eroded due to dynamic action of tires in the presence of water). This Thesis focuses on the research on the effects …


Comparison Of Bicycle Transportation Systems In El Paso And Prague, Jose C Hernandez Jan 2015

Comparison Of Bicycle Transportation Systems In El Paso And Prague, Jose C Hernandez

Open Access Theses & Dissertations

Bicycle transportation infrastructure has an important role in bicycle transportation mode. Every year there are hundreds of accidents where bicyclist are involve, because there is not a good infrastructure for bicycles in the roads bicyclists have a potential risk. One of the main purposes is maintain the bicyclistsâ?? safety in the roads to attract more people to use this eco-friendly transportation mode. The goal of this Thesis is compare the bicycle infrastructure in two different countries, United States and Czech Republic. The history and the main terminology are described in firsts chapters. Based on law and regulations, design criteria and …


A Stochastic Approach For Pavement Condition Projections And Budget Needs For The Mtc Pavement Management System, Rafael Arturo Ramirez Flores Jan 2015

A Stochastic Approach For Pavement Condition Projections And Budget Needs For The Mtc Pavement Management System, Rafael Arturo Ramirez Flores

Open Access Theses & Dissertations

Pavement management decision-making is the most important task for officials in transportation agencies, who develop maintenance and rehabilitation programs. Information about historical pavement network performance is needed for decision-making; pavement management systems (PMS) provide means to organize road network data to improve the pavement network condition. PMS have prediction performance models to forecast the future condition of the pavement networks with information required for decision-making; these models can be deterministic or probabilistic. Pavement performance deterministic models are commonly used in PMS, but they do not consider the uncertainty in forecasting pavement performance. Pavement performance depends on many random factors like …


Performance Life Of Various Hot Mix Asphalt Mixtures In Texas, Danniel David Rodriguez Jan 2015

Performance Life Of Various Hot Mix Asphalt Mixtures In Texas, Danniel David Rodriguez

Open Access Theses & Dissertations

Typically, pavement engineers in subjectively estimate the service lives of various hot-mix asphalt (HMA) mixtures as part of the life-cycle cost analysis considering the staged design and rehabilitation of flexible pavements. This study proposes the performance lives for the various dense-graded (conventional) mixtures, stone-matrix asphalts (SMA), permeable friction courses (PFC), performance design mixtures and other mixtures placed in Texas. A necessary and significant aspect of the approach involved data mining and merging several pavement management databases (Letting Database, DCIS and PMIS) to obtain mixture longevity data along with historical PMIS information. The product of the linking process resulted in the …


Evaluation Of Point Of Use Drinking Water Treatment Systems For Colonias In The Southwest United States, Isaac Campos Flores Jan 2015

Evaluation Of Point Of Use Drinking Water Treatment Systems For Colonias In The Southwest United States, Isaac Campos Flores

Open Access Theses & Dissertations

Clean drinking water is often taken for granted in first world countries, such as the United States. However, thousands of colonias residents (settlements in the Southwest US that lack access to basic infrastructure) still lack access to clean drinking water. Such is the case in the Paso Del Norte Region. In Doña Ana County, NM, and El Paso County, TX, colonia residents typically rely on shallow domestic wells and hauled water, respectively. However, both water sources can pose health concerns from elevated total dissolved solids and microbiological contamination. With connection to centralized water treatment and distribution still years away, colonias …


Alternative Fatigue Cracking Resistance Assessment Criteria Of Asphalt Mixtures With Overlay Tester, Alejandro Miramontes Jan 2015

Alternative Fatigue Cracking Resistance Assessment Criteria Of Asphalt Mixtures With Overlay Tester, Alejandro Miramontes

Open Access Theses & Dissertations

The accumulation of damage due to cracking of hot mix asphalt (HMA) layers under repeated loading along with the climatic effects is known as fatigue cracking. The Overlay Tester (OT) has been implemented or considered by several highway agencies as an index to evaluate the cracking susceptibility and resistance to cracking of asphalt mixtures in the laboratory. The performance indicator used to measure the quality of the HMA mixes is the number of cycles that a specimen may resist during the test until the crack appears and fully propagates to the top of the specimen. The repeatability of the number …


A Methodology For Use Of Digital Image Correlation For Hot Mix Asphalt Testing, Estefany Ramos Jan 2015

A Methodology For Use Of Digital Image Correlation For Hot Mix Asphalt Testing, Estefany Ramos

Open Access Theses & Dissertations

Digital Image Correlation (DIC) is a relatively new technology which aids in the measurement of material properties without the need for installation of sensors. DIC is a noncontact measuring technique that requires the specimen to be marked with a random speckled pattern and to be photographed during the test. The photographs are then post-processed based on the location of the pattern throughout the test. DIC can aid in calculating properties that would otherwise be too difficult even with other measuring instruments.

The objective of this Thesis is to discuss the methodology and validate the use of DIC in different hot …


A Rapid Approach For Considering Nonlinear Response Of Flexible Pavements Under Fwd And Estimation Of Remaining Lives Of Pavements, Shahabaldin Shirazi Jan 2015

A Rapid Approach For Considering Nonlinear Response Of Flexible Pavements Under Fwd And Estimation Of Remaining Lives Of Pavements, Shahabaldin Shirazi

Open Access Theses & Dissertations

Most mechanistic empirical pavement analyses are based on the layered elastic models where the stress sensitivity of geomaterials and their nonlinearity are either ignored or accounted for indirectly. Advanced numerical models, such as finite element models, are required to consider the nonlinear nature of the geomaterials. Existing pavements are often tested with the Falling Weight Deflectometer (FWD) to estimate the input moduli to the layered elastic models in order to estimate remaining life and structural capacity of pavements. It has been more than 30 years that FWD tests are being performed to measure structural adequacy of pavements. Backcalculation is the …


Reliability And Sensitivity Analysis For Micro-Meteoroids And Orbital Debris Protection Models Using First-Order Reliability Methods (Form)., Levi Pereda Jan 2015

Reliability And Sensitivity Analysis For Micro-Meteoroids And Orbital Debris Protection Models Using First-Order Reliability Methods (Form)., Levi Pereda

Open Access Theses & Dissertations

Abstract This Thesis provides a probabilistic assessment of the micro-meteoroids and orbital debris (MMOD) impact protection structures. The assessment is based on first-order reliability methods that use Ballistic Limit equations traditionally used by NASA for the design of shields. The research demonstrates how the structural reliability methods can be implemented into the aeronautics and astronautics field. NASA is continuously developing new techniques that allow the consideration of the uncertainty that exists in the design of their space structures. Nevertheless, some of their design approaches are still deterministic. For example MMOD ballistic limit equations used for the design of the MMOD …


Recovery Of Nutrient Nitrogen From Municipal Wastewater Residuals By Gas Membrane Separation, Evelyn Rios Jan 2015

Recovery Of Nutrient Nitrogen From Municipal Wastewater Residuals By Gas Membrane Separation, Evelyn Rios

Open Access Theses & Dissertations

There are relatively high amounts of ammonia returned to the headworks of a municipal wastewater plant that are extracted from the dewatering process. This ammonia load contributes to a significant oxygen demand in the secondary treatment, requiring greater air blower energy costs. This goal of this research was to evaluate the feasibility of the recovery of an ammonium sulfate product from belt press filtrate. The objectives of this research were to: (1) analyze wastewater treatment average monthly data flows and constituents with respect to ammonia nitrification, (2) the evaluate the technical performance of a two sage gas-separation membrane for recovering …


Accuracy And Precision Evaluation Of Traffic Speed Pavement Deflection Devices, Jorge Velarde Jan 2015

Accuracy And Precision Evaluation Of Traffic Speed Pavement Deflection Devices, Jorge Velarde

Open Access Theses & Dissertations

Pavement structural adequacy is considered an important aspect of the pavement management activities and can be incorporated by using surface pavement deflections. Continuous deflection technology, which has been around for several years, can potentially supplant single point deflection measurements provided by the Falling Weight Deflectometer (FWD). Previous studies have evaluated the traffic speed deflection devices (TSDD) accuracy and precision by comparing their results with FWD measurements. Although appropriate correlations and indices to compensate for the differences in load have been made, a direct comparison under the same loading conditions has not been reported in the literature.

The goal of this …


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 …


Advanced Sustainable Concrete Materials For Infrastructure Applications, Kaylea Ann Smith Jan 2015

Advanced Sustainable Concrete Materials For Infrastructure Applications, Kaylea Ann Smith

Masters Theses

"This study was performed to examine the effects of cement replaced by high volumes of Class C fly-ash on durability characteristics of concrete up to 120 days. Specifically, this study investigates possibility of amending American Society for Testing and Materials (ASTM) to allow High Volume Fly-ash (HVFA) concrete to cure until later ages prior to testing instead of 28 days. Five mix designs were compared with varying fly-ash percentages from 0 to 70% (by total cementitious mass). No other additives were present in any of the five mix designs. Water-to-cementitious ratio (w/cm) and total cementitious material remained constant as 0.40 …


Laboratory Evaluation Of Organic Soil Mixing, Spencer Dean Baker Jan 2015

Laboratory Evaluation Of Organic Soil Mixing, Spencer Dean Baker

USF Tampa Graduate Theses and Dissertations

Organic soils present a difficult challenge for roadway designers and construction due to the high compressibility of the soil structure, the often associated high water table, and the high moisture content. For other soft or loose soils (inorganic soils), stabilization via cement or similar binders (a method called soil mixing) has proven to be an effective solution. To this end, the Federal Highway Administration has published a comprehensive design manual for these techniques. Organic soils, however, are not addressed therein to a level of confidence for design, as organic soils do not follow the trends of inorganic soils. This has …


Effect Of Dosage Of Non-Chloride Accelerator Versus Chloride Accelerator On The Cracking Potential Of Concrete Repair Slabs, Thomas F. Meagher Jan 2015

Effect Of Dosage Of Non-Chloride Accelerator Versus Chloride Accelerator On The Cracking Potential Of Concrete Repair Slabs, Thomas F. Meagher

USF Tampa Graduate Theses and Dissertations

Due to strict placement time and strength constraints during the construction of concrete pavement repair slabs, accelerators must be incorporated into the mixture design. Since the most common accelerator, calcium chloride, promotes corrosion of concrete reinforcement, a calcium nitrate-based accelerator was studied as an alternative. To replicate mixtures used in the field, commercial accelerators commonly used in concrete pavement repair slabs were used in the current study. Crack risk of different mixtures was assessed using modeling and cracking frame testing. HIPERPAV modeling was conducted using several measured mixture properties; namely, concrete mechanical properties, strength-based and heat of hydration-based activation energies, …


Hybrid Jacketing For Rapid Repair Of Seismically Damaged Reinforced Concrete Columns, Mostafa Fakharifar, Genda Chen, Mahdi Arezoumandi, Mohamed Elgawady Jan 2015

Hybrid Jacketing For Rapid Repair Of Seismically Damaged Reinforced Concrete Columns, Mostafa Fakharifar, Genda Chen, Mahdi Arezoumandi, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study proposes hybrid jacketing for rapid repair of seismically damaged concrete columns for bridge safety. The hybrid jacketing for a reinforced concrete (RC) column is composed of a thin cold-formed steel sheet wrapped around the column and its outside prestressing strands. Although the prestressing strands can prevent buckling of the confining steel sheet, the steel sheet can in turn prevent the prestressing strands from cutting into the concrete. The hybrid jacketing concept was validated with testing of a large-scale RC column with lap splice deficiency typical of pre-1970 bridge constructions in the Central United States. Results from the original …


Lateral Torsional Buckling Response In Glass Fiber Reinforced Polymer Composite Beams And Comparison With Ansys Modeling & Design Equations, Santosh Vangala Jan 2015

Lateral Torsional Buckling Response In Glass Fiber Reinforced Polymer Composite Beams And Comparison With Ansys Modeling & Design Equations, Santosh Vangala

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glass fiber reinforced polymer (GFRP) composites have the potential to replace the existing conventional materials in Civil Engineering like steel and concrete. Such potential can be attributed to the numerous advantages GFRP composites have over conventional materials. Some of the advantages are: high strength-to-weight ratio, corrosion resistance, low life cycle cost and maintenance, nonmagnetic and electronic transparency. As the application of GFRP is on the rise, the need for developing accurate design equations for these materials has been imperative. The GFRP composites are manufactured through pultrusion and although they have numerous advantages they are less stiff than similar profiles made …


Performance Characteristics Of Polyethylene Terephthalate (Pet) Modified Asphalt, Matthew D. Earnest Jan 2015

Performance Characteristics Of Polyethylene Terephthalate (Pet) Modified Asphalt, Matthew D. Earnest

College of Graduate Studies: Theses & Dissertations

Polyethylene terephthalate (PET) plastic is utilized primarily in food and beverage packaging. Although a portion of waste PET is recycled, the majority of the waste is buried in landfills. Therefore, the use of ground PET particles in asphalt may provide an environmentally friendly solution for the disposal of large quantities of PET waste. This study evaluated the performance of PET as an asphalt modifier with both asphalt binder and asphalt mixture testing. The binder testing was conducted on wet process blends produced with a high shear mixer at PET contents of 5, 10, and 15 percent by weight of the …


Lighting Design In Europe: Aligning The Demands For Lower Energy Usage With Better Quality., Kevin Kelly, James Duff Jan 2015

Lighting Design In Europe: Aligning The Demands For Lower Energy Usage With Better Quality., Kevin Kelly, James Duff

Articles

Lighting design is one of the fastest changing areas in building engineering. It has evolved significantly in recent years due to changing technology and demands for improved quality, better control, reduced energy and sustainability. This paper is an overview of what is happening in Europe and elsewhere and examines the literature to find that latest recommendations in the Code for Lighting issued by the SLL (Society of Light and Lighting) in the UK change previous demands for equal illuminance across a working plane to more specific and demanding criteria. There are recommendations for qualitative metrics and better distribution of light …


Behavior Of Hollow-Core Fiber Reinforced Polymer-Concrete-Steel Bridge Columns Under Extreme Loading, Omar I. Abdelkarim Jan 2015

Behavior Of Hollow-Core Fiber Reinforced Polymer-Concrete-Steel Bridge Columns Under Extreme Loading, Omar I. Abdelkarim

Doctoral Dissertations

"This study introduces an investigation of the behavior of innovative, resilient, and quickly-constructed hollow-core fiber reinforced polymer-concrete-steel (HC-FCS) bridge columns under extreme loading. The HC-FCS column consists of a concrete wall sandwiched between an outer fiber reinforced polymer (FRP) tube and an inner steel tube. The steel tube was embedded into a reinforced concrete footing with an embedded length of 1.6-1.8 times the diameter of the steel tube. The FRP tube only confined the concrete wall and truncated at the top of the footing level. The hollow steel tube was the only reinforcement for shear and flexure inside the HC-FCS …


Dynamic Behavior Of Operational Wind Turbines Considering Aerodynamic And Seismic Load Interaction, Mohammad-Amin Asareh Jan 2015

Dynamic Behavior Of Operational Wind Turbines Considering Aerodynamic And Seismic Load Interaction, Mohammad-Amin Asareh

Doctoral Dissertations

"With the advancements in the wind energy production industry, the demand for a cost effective and safe design of wind turbine structures is growing rapidly. The wide deployment of wind turbines in locations with high seismic hazard has lead engineers to take into account a more comprehensive seismic design of such structures. In response to the need for a computational tool that can perform coupled simulations of wind and seismic loads, a seismic module has been developed for the publicly available National Renewable Energy Laboratory (NREL) code, FAST, at the first step of this research. This achievement allows engineers working …


An Integrated Study For Hybrid Composite Beam (Hcb) Structures, Mohamed Abdelkhalik Aboelseoud Jan 2015

An Integrated Study For Hybrid Composite Beam (Hcb) Structures, Mohamed Abdelkhalik Aboelseoud

Doctoral Dissertations

"The hybrid composite beam (HCB) consists of a self consolidating concrete (SCC) arch that is tied at the end by galvanized strands. The tied arch is encapsulated by a glass fiber reinforced polymer (GFRP) shell. A limited number of researches have studied the essential design methodologies and long-term performance of the HCB. The research presented in this dissertation aimed to more fundamentally understand the structural behavior of this new beam and evaluate its durability. This research study was conducted through four phases. A full-scale bridge load testing was conducted on a single-web HCB bridge during the first phase. The first …


Reliability-Based Optimization Design Of Geosynthetic Reinforced Embankment Slopes, Michelle (Mingyan) Deng Jan 2015

Reliability-Based Optimization Design Of Geosynthetic Reinforced Embankment Slopes, Michelle (Mingyan) Deng

Doctoral Dissertations

"This study examines the optimization design of geosynthetic reinforced embankment slopes (GRES) considering both economic benefits and technical safety requirements. In engineering design, cost is always a big concern. To minimize the cost, engineers tend to seek an optimal combination of design parameters among the considered alternatives while ensuring the optimal solution is safe. Reliability-based optimization (RBO) is such a technique that provides engineers the optimal design with the minimum cost while all technical design requirements are satisfied. The research goal of this study is to implement a mathematical formulation algorithm of the RBO technique in GRES design. To achieve …


Shape Based Classification And Functional Forecast Of Traffic Flow Profiles, Wasim Kayani Jan 2015

Shape Based Classification And Functional Forecast Of Traffic Flow Profiles, Wasim Kayani

Doctoral Dissertations

This dissertation proposes a methodology for traffic flow pattern analysis, its validation, and forecasting. The shape of the daily traffic flows are directly related to the commuter’s traffic behavior which merit analysis based on their shape characteristics. As a departure from the traditional approaches, this research proposed a methodology based on shape for traffic flow analysis. Specifically, Granulometric Size Distributions (GSDs) were used to achieve classification of daily traffic flow patterns. A mathematical morphology method was used that allows the clustering of shapes. The proposed methodology leads to discovery of interesting daily traffic phenomena such as five normal daily traffic …


Performance Analysis And Modelling Of Hybrid Photovoltaic-Thermal Solar Panels, Nicole C. Annis Jan 2015

Performance Analysis And Modelling Of Hybrid Photovoltaic-Thermal Solar Panels, Nicole C. Annis

Doctoral Dissertations

A photovoltaic-thermal (PVT) panel was constructed, tested, and modelled using both MATLAB and TRNSYS. During the experimental testing, which took place on the Missouri University of Science and Technology campus in Rolla, Missouri; two identical PVT panels were tested alongside two PV panels to gather an electrical baseline for comparison. Approximately 69 days’ worth of data were of data were collected during the summer of 2014. The PV electrical, PVT electrical, PVT thermal and PVT combined (electrical and thermal) efficiencies were 3.5-5.6%, 3.4-5.4%, 20.9-11.6%, and 24.3-17.0%, respectively.

A MATLAB program was developed using existing equations for one-dimensional, quasi-steady model of …


Development, Testing, And Analytical Modeling Of Fiber-Reinforced Polymer Bridge Deck Panels, Hesham R. Tuwair Jan 2015

Development, Testing, And Analytical Modeling Of Fiber-Reinforced Polymer Bridge Deck Panels, Hesham R. Tuwair

Doctoral Dissertations

A fiber-reinforced, polyurethane foam core was developed, tested, and evaluated as a possible replacement for the costly honeycomb core that is currently used to manufacture fiber-reinforced polymer (FRP) bridge deck panels. Replacing these panels would reduce both initial production costs and construction times while also enhancing structural performance. Experimental, numerical, and analytical investigations were each conducted. Three different polyurethane foam (PU) configurations were used for the inner core during the study’s first phase. These configurations consisted of a high-density PU foam (Type 1), a gridwork of thin, interconnecting, glass fiber/resin webs that formed a bidirectional gridwork in-filled with a low-density …


Unmanned Aircraft Systems Image Collection And Computer Vision Image Processing For Surveying And Mapping That Meets Professional Needs, James Preston Peterson Ii Jan 2015

Unmanned Aircraft Systems Image Collection And Computer Vision Image Processing For Surveying And Mapping That Meets Professional Needs, James Preston Peterson Ii

Doctoral Dissertations

"Unmanned Aerial Systems (UAS) are rapidly blurring the lines between traditional and close range photogrammetry, and between surveying and photogrammetry. UAS are providing an economic platform for performing aerial surveying on small projects. The focus of this research was to describe traditional photogrammetric imagery and Light Detection and Ranging (LiDAR) geospatial products, describe close range photogrammetry (CRP), introduce UAS and computer vision (CV), and investigate whether industry mapping standards for accuracy can be met using UAS collection and CV processing. A 120-acre site was selected and 97 aerial targets were surveyed for evaluation purposes. Four UAS flights of varying heights …


Mechanical Characteristics Of Organically Modified Fly Ash-Kaolinite Mixtures, Xin Kang Jan 2015

Mechanical Characteristics Of Organically Modified Fly Ash-Kaolinite Mixtures, Xin Kang

Doctoral Dissertations

"Fly ash is a hazardous waste material to the environment. Beneficial reuse of fly ash, however, brings economic and environmental benefits, i.e., decreases the cost of disposal, reduces greenhouse gas emission, and improves mechanical properties of construction materials. Due to the lack of pozzolanic properties, the reuse rate of Class F fly ash in geotechnical engineering is relatively low (ACAA 2013). In order to promote the effectiveness and sustainability of high volume reuse of class F fly ash in geotechnical engineering, biopolymers (Chitosan, and Xanthan gum) and synthetic polymers (Polyethylene Oxide, PEO) were used instead of the traditional stabilizers to …


Behavior Of Crimped Cold-Formed Steel C-Section Beams, Jeffrey Devon Smith Jan 2015

Behavior Of Crimped Cold-Formed Steel C-Section Beams, Jeffrey Devon Smith

Masters Theses

"This work covers the behavior of crimped cold-formed steel C-section beams under flexural loading. The specific beam shape that was tested was 600S162-54. The crimps were placed in the flange and web of the beam to curve the beam. Three crimp sizes were tested: 0.5 degree, 1.5 degree, and 3.0 degree. In construction practice, the company placed a reinforcing steel band that overlapped the crimped areas to restore strength. These various crimp degrees were tested to evaluate how much strength, if any, was lost. The reinforcing steel band was tested simultaneously with the beam to evaluate if its presence significantly …