Civil and Environmental Engineering Commons^™

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 …

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 …

Novel Engineered Nanomaterials For Water Remediation And Gas Adsorption: Graphene Oxide And Carbon Nanotubes Decorated With Metal-Organic Frameworks And Magnetic Nanoparticles, Vahid Jabbari

Open Access Theses & Dissertations

In the current study, a series of novel magnetic and non-magnetic hybrid nanocomposites based on metal-organic frameworks (MOFs) of M3(BTC)2 (M: Ni, Cu, Zn, and Cd), graphene oxide (GrO), and carbon nanotubes (CNTs), and Fe3O4 magnetic nanoparticles (MNPs) were developed via a green, simple and versatile solvothermal method at which GrO and CNT were used as platform to grow the MOFs and Fe3O4 MNPs over them. The as-synthesized nanocomposites were characterized by XRD, SEM, TEM, XPS, IR, Raman, TGA, and N2 adsorption/desorption isotherms. Morphological analysis confirmed successful growth of nano-size Fe3O4 MNPs and M3(BTC)2 MOFs over GrO and CNT platforms. …

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

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 …

Evaluating Methods Of Field-Based 3d Visualization And Their Application To Mapping Metamorphic Terranes: An Example From The Panamint Mountains, California, Jade Ashley Brush

Open Access Theses & Dissertations

Field geology has traditionally relied on 2D, paper-based workflows, but digital mapping techniques are rapidly replacing these outdated methods because they allow for more efficient and accurate mapping. This research applies digital mapping techniques and two terrestrially-based 3D visualization technologies, photogrammetry and Light Detection and Ranging (LiDAR), to the study of metamorphic terranes in the Panamint Mountains, California. This study reports on the spatial accuracy of TINs (triangulated irregular networks) generated from both photogrammetry and ground-based LiDAR using a terrestrial laser scanner (TLS) and discusses how spatial accuracy can be increased. Two levels of comparison were used to test spatial …

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 …

High Temperature Helical Tubular Receiver For Concentrating Solar Power System, Nazmul Hossain

Open Access Theses & Dissertations

In the field of conventional cleaner power generation technology, concentrating solar power systems have introduced remarkable opportunity. In a solar power tower, solar energy concentrated by the heliostats at a single point produces very high temperature. Falling solid particles or heat transfer fluid passing through that high temperature region absorbs heat to generate electricity. Increasing the residence time will result in more heat gain and increase efficiency. A novel design of solar receiver for both fluid and solid particle is approached in this paper which can increase residence time resulting in higher temperature gain in one cycle compared to conventional …

Wind Farm Optimization Using Evolutionary Algorithms, Carlos Marco Ituarte-Villarreal

Open Access Theses & Dissertations

In recent years, the wind power industry has focused its efforts on solving the Wind Farm Layout Optimization (WFLO) problem. Wind resource assessment is a pivotal step in optimizing the wind-farm design and siting and, in determining whether a project is economically feasible or not. In the present work, three (3) different optimization methods are proposed for the solution of the WFLO: (i) A modified Viral System Algorithm applied to the optimization of the proper location of the components in a wind-farm to maximize the energy output given a stated wind environment of the site. The optimization problem is formulated …

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 …

Safety Measures For Trucks: A Comparison Between Eu And U.S., Jan Kapusta

Open Access Theses & Dissertations

Road transportation is playing an important role in almost all of the freight movements and contributes to the economy. It has the highest share in the modal division of transported goods. This situation is not about to change in next years to come. Therefore, it is necessary to change the current situation and create rules and regulations that would lead to decrease in number of accidents either in EU or in U.S. The goal of this research is to analyze selected parameters related to the safety of truck transportation in EU and in U.S. This thesis also identifies and compares …

Water Recovery From Silica Saturated Ro Concentrate By The Concentrate Enhanced Reverse Osmosis Process, Gautam Patwardhan

Open Access Theses & Dissertations

Membrane fouling due to silica precipitation during reverse osmosis (RO) continues to be documented as the most common challenge in attaining stable continuous operation of RO systems across water treatment plants (1). Silica scale precipitation is time dependent and involves multiple steps leading to aqueous polymerization, condensation of polymers to form colloids, and deposition onto a solid surface (2). Exceeding the solubility of silica, widely considered to be in the range of 100-140 ppm, under a pH of 8 at 25 °C by various researchers, results in the precipitation of silica on the membranes, thereby limiting water recovery. Once the …

Why Ricker Wavelets Are Successful In Processing Seismic Data: Towards A Theoretical Explanation, Afshin Gholamy Salehabady

Open Access Theses & Dissertations

In many engineering applications ranging from engineering seismology to petroleum engineering and civil engineering, processing seismic data plays a key role. In processing seismic data, it turns out to be very efficient to describe the signal's spectrum as a linear combination of Ricker wavelet spectra.

In this Thesis, we provide a possible theoretical explanation for this empirical efficiency. Specifically, signal propagation through several layers is discussed, and it is shown that the Ricker wavelet is the simplest non-trivial solution for the corresponding data processing problem, under the condition that the described properties of the approximation family are satisfied.

An Explanatory And Comparative Analysis Of Freight Transportation In Eu And U.S. Highways, Luis Alberto Hernandez

Open Access Theses & Dissertations

This thesis provides resources for data collection regarding road freight transportation in the Unites States and the European Union, as well as an explanatory description of data available at each source. Afterwards, individual analysis of the current state of affairs of the highway freight transportation systems in U.S. and EU are performed. Thereafter, an explanatory and comparative analysis between the two land freight transportation systems is performed in terms of regulatory authorities and associations, trucks volume flow, freight weight and volume flow, major issues affecting the system, infrastructure funding sources, and major logistics hubs. Besides, a correlation analysis was performed …

Simulation Of Heat And Mass Transfer In Suns River Solar Distillation, Houman Azari

Open Access Theses & Dissertations

Many regions around the world have limited fresh water resources, and we need to desalinate brackish water resources for drinking and irrigation purposes. Most of the world is also facing energy challenges which encourages engineers and scientists to use renewable energy resources instead of hydrocarbon fuels. Arid regions such as the Middle East, many African countries, and the southwestern United States typically have abundant solar irradiance and brackish or saline water supplies. Solar-thermal desalination could be an important supply of fresh water in these regions.

The classic solar still is not efficient for providing large amounts of clean water for …

Integrated Sustainability Decision-Making Framework, Michael Paul Cole

Open Access Theses & Dissertations

The Integrated Sustainability Decision-Making Framework (ISDMF) is an 'ideal case' framework developed at the University of Texas El Paso (UTEP) from 2012 to present to provide the most comprehensive and concise sustainability strategy and decision-making template available.

Sustainable decision-making improves community Quality of Life, but is often beyond the reach of the majority. A framework that is most approachable, actionable, and adoptable can accelerate convergence on and continued operation of a sustainable solution. Research confirms that published frameworks continuously emerge, and are infinite in number. Iterations benefit from prior work, and contribution occurs when an 'ideal case' is envisioned, best …

Studying The Parameters Involved With Modulus-Based Construction Quality Control For Compaction Of Unbound Pavement Layers, Mehran Mazari

Open Access Theses & Dissertations

Pavement performance is impacted by several factors such as the properties of the materials, combination of traffic and loading, structural capability, climate changes and construction process. Earthwork and unbound materials is an important part of pavement constructions since most of the distresses can be related to these geomaterials. Appropriate process control, proper processing of geomaterials, adequate amount of moisture and suitable compaction effort would ensure the required density and stiffness of the compacted pavement layer. The Nuclear Density Gauge (NDG) has been the primary means of Quality Control and Quality Acceptance (QC/QA) by State Highway Agencies (SHAs) and department of …

Using Fair Division Methods For Allocating Transportation Funds, Edith Montes

Open Access Theses & Dissertations

Current transportation funding allocation methods are very complex due to limited budgets and conflicting interests. In order to maintain an efficient infrastructure transportation system, agencies must balance the allocation of funds required either to increase the roadway capacity or to preserve the existing roads in service. Depending on the target objectives and specific constraints, the funding allocation process is approached using different methods. The funding allocation process is usually addressed using expert judgment which involves subjective criteria, weighted formulas with pre-established priorities, or a combination of both. However, formula-based funding allocation methods may lead to the public's disagreement if final …

High-Recovery Inland Desalination: Concentrate Treatment By Electrodialysis And Batch Reverse Osmosis, Noe Ortega-Corral

Open Access Theses & Dissertations

Since fresh water resources are finite and stressed, it is of the utmost importance to develop alternative water resources. Efforts to recover and treat impaired water are happening in arid areas around the world, where water resources are already scarce. Such efforts are particularly focused on high-recovery treatment systems, accomplished by reducing the amount of liquid discharge with the intent to eventually reach zero liquid discharge. The goal of this research is to improve the feasibility of highrecovery inland desalination systems. Two types of high-recovery treatment systems were selected for study: (1) combined reverse osmosis (RO) and electrodialysis (ED) systems, …

Permit Tool: Development Of An Algorithm To Determine Performance Life Of Hma Mixes In Texas, Luis Alberto Torres Escobedo

Open Access Theses & Dissertations

A number of hot mix asphalt (HMA) types, such as permeable friction course (PFC), stone mastic asphalt (SMA), performance design mixes and conventional dense graded mixes are currently used to construct or overlay Texas roads. One of the important inputs into current pavement design programs used by the Texas Department of Transportation (TxDOT) is the performance lives of HMA mixes. To determine the best mix type for a particular job or to analyze the performance of a mix or a road, a new system can be developed to rationally quantify the HMA mix performance. This system must have access to …

Enhanced Finite Element Modeling Of The Thermo-Mechanical Responses Of Jointed Pcc Pavements Under Environmental And Traffic Loads, Mohammad Ali Zokaei Ashtiani

Open Access Theses & Dissertations

Jointed plain concrete pavements (JPCP) are the most commonly used type of rigid pavement systems and the accurate modeling of their thermo-mechanical responses is of primary importance in a mechanistic-empirical pavement design procedure. In JPCP, the temperature gradient and resulting slab shape play a crucial role in the magnitude of stresses and deflections caused by the superimposed traffic loads. Temperature gradients through the slab depth can produce thermal curling in slabs and can also produce slab expansion and contraction, which leads to the generation of frictional tractions between slabs and foundation. The prediction of these frictional tractions is complicated by …

Evaluation Of Ozone Trends In Southern Doña Ana County, New Mexico Thru Wind Rose Analysis And Use Of Noaa Hysplit Model, Maria Aurelia Sisneros

Open Access Theses & Dissertations

The objective of this study was to determine whether increasing ozone concentrations in 2012 and 2013 at the Santa Teresa air quality monitor in Doña Ana County, New Mexico were due to a local point source impacting this monitor only or part of a regional phenomenon that affects all the monitors within the Paso del Norte Region. In addition, the study focused on identifying local and regional/long-range source areas contributing transport ozone to the study area (southern Doña Ana County).

The study showed that increasing ozone levels were not unique to the Santa Teresa monitor due to the fact that …

Transatlantic Maritime Transportation Between The Czech Republic And The United States, Petr Toman

Open Access Theses & Dissertations

Maritime transportation is the backbone of today´s world trade and therefore there special attention should be paid to all subjects concerning this mode of transportation. It is also necessary to complement maritime transportation by other modes, such as rail and/or truck (road). This thesis deals with the problems of maritime transportation and provides the summary of recent developments, trends and statistics mainly on Transatlantic maritime routes (Europe to U.S.). Besides maritime transportation, this thesis also reviews the trends and statistics of rail and truck (road) transportation in U.S. and Europe.

The second part of thesis seeks to create a mathematical …

Sustainable Public Transportation In Large Cities: Demand Estimation, Tadeas Umlauf

Open Access Theses & Dissertations

Public transportation helps to decrease the negative externalities caused by people's mobility. In many countries, the total number of vehicles and traffic has risen many times in the last decades but there is limited space to improve infrastructure in the cities. Large cities all over the world have a lot of issues with congestion, traffic noise, emission of greenhouse gases, and accidents. According to many international examples, sustainable public transportation in combination with synergistic projects (park & ride, kiss & ride, bike & ride) can help to overcome these issues. Therefore new transit modes and routes have been implemented in …

A Method To Reduce Plastic Shrinkage Cracking Of Concrete Using Re-Vibration Technique, Mustafa Abushaala Aldalinsi

Open Access Theses & Dissertations

One of the problems that reduce durability; thus, performance of concrete is the development of plastic shrinkage cracking (PSC). Traditionally, the development of PSC has been minimized by controlling its exposure to weather conditions or by adding fibers. In this study, concrete re-vibration was used as an alternative technique to control PSC because of the limited availability of fibers in the developing countries. In this study, the wait time after slab casting and before vibration was selected to be 90 minutes while length of re-vibration time was varied from 15 to 45 seconds. Also, the water-cement ratios were selected to …

Characterization Of Particulate Matter Concentrations (Pm10, Pm10-2.5, And Pm2.5) At High-Altitude School And Residential Mircroenvironments In Quito, Ecuador, Teresa Montoya

Open Access Theses & Dissertations

Air quality issues in Latin American countries are especially challenging because of the limited availability of resources to address them, lack of stringent standards and the rapid and uncontrolled growth of their cities increasing the number of vehicles on the road and the expansion of the industry. In particular, the city of Quito, Ecuador exacerbates its environmental issues by its high-altitude (2800 m above sea level) coupled by its location around a mountain valley and frequent temperature inversions.

This study focused on evaluating the spatial variation of the PM concentrations and the effectiveness of a central monitoring network in representing …

Model Fusion: A New Approach To Processing Heterogeneous Data, Omar Ochoa

Open Access Theses & Dissertations

In many practical situations, it is necessary to extract

information from data of different types. For example, in geosciences, several sources of data can be used to determine the interior structure of the earth: the first arriving waves from earthquakes and from man-made sources, measurements of the earth's gravity field, measurements of the dispersion of surface waves generated by earthquakes, etc. At present, most existing data processing techniques deal only with data of one type.

A joint use of all the information derived from multiple types of data sources is an important theoretical and practical challenge. Such a joint use …

Purification Of Sodium Sulfate By Crystallization, Perla Teresita Torres

Open Access Theses & Dissertations

Sodium sulfate can be recovered from a dilute solution by concentrating it by conventional water treatment techniques like reverse osmosis and electrodialysis; however, those processes also concentrate impurities like arsenic. The sodium sulfate would have commercial use if it can be recovered in an arsenic-free form. This study demonstrated that sodium sulfate could be separated from impurities using slow cooling crystallization in a novel apparatus developed and designed during the experimentation. This device is called a heat exchanger crystallizer and allows slow cooling crystallization in order to grow pure crystals of sodium sulfate decahydrate. Crystals grown in the heat exchanger …

Investigation Into The Operation And Safety Of Freeway Auxiliary Lanes: Towards Uniform Design Guidelines, Yubian Wang

Open Access Theses & Dissertations

Freeways operate closest to the purest form of uninterrupted traffic flow. There is no constant interruption to traffic flow (such as stop sign and traffic signal), and access is limited to ramp locations. Therefore, at freeways, bottlenecks, if exist, are usually caused by merging and diverging traffic at ramp locations. Bottleneck removal at freeway ramp areas can reduce average freeway commuter delay. Currently, engineers may add auxiliary lanes at ramp areas to mitigate or remove bottlenecks.

The American Association of State Highway Transportation Officials (AASHTO) publication A Policy on Geometric Design of Highways and Streets, commonly known as the "Green …

Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob

Open Access Theses & Dissertations

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This Dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and …