Engineering Commons^™

Geospatial Relationship Of Intelligent Compaction Measurement Values With In-Situ Testing For Quality Assessment Of Geomaterials, Luis Alberto Lemus

Open Access Theses & Dissertations

The implementation of Intelligent Compaction (IC) in the construction of transportation infrastructure as a tool for quality control of compacted geomaterials has attracted the attention of a number of highway agencies. Compaction quality has been conventionally assessed using density, and to a less extent, modulus-based spot measurements at selected locations along the roadway section. While spot measurements do not provide a thorough rendition of the level of compaction of the roadway, IC technology is effective in meeting full coverage requirements. IC roller measurements are accelerometer-based measurements recording machine-ground interaction assumed to be indicative of the stiffness of the compacted geomaterial. …

High Recovery Inland Desalination: A Technical And Economic Performance Evaluation Of Zero Discharge Desalination And Other Technologies, Malynda Aragon Cappelle

Open Access Theses & Dissertations

Increasing population and diminishing freshwater resources are leading to increased competition between users of freshwater, both in terms of surface water and groundwater. Desalination can augment the water supply, but conventional approaches like reverse osmosis are usually limited to 70-80% recovery. Inland brine disposal options are often limited, presenting significant technical and economic obstacles to implementing desalination technology. In comparison to conventional desalination technologies, high recovery desalination methods such as Zero Discharge Desalination (ZDD) offer substantially higher potable water yield (i.e., 95-98%) from brackish water. ZDD is a hybrid process that combines reverse osmosis (RO) or nanofiltration (NF) with electrodialysis …

A Comparative Study Characterizing Traffic Related Air Pollutant Concentrations At Near-Road Communities In El Paso, Texas, Adan Rangel

Open Access Theses & Dissertations

Numerous scientific studies have demonstrated the influence of traffic related air pollution at near-road communities and the associated health risks for these populations. This study uses on-site air quality monitors to characterize air pollutants at near-road schools in El Paso, TX to understand children's exposure to traffic-related air pollutants. Ambient air monitoring stations were installed at Coldwell Elementary, Bliss Elementary, and a residential house located in close proximity to major inter-state roadways. In this study, air quality data for PM2.5, PM10, NO2, and O3 was collected over a period of nine weeks in Fall 2018. The spatial and temporal variability …

Back Calculation Of Intelligent Compaction Data For Mechanical Properties Of Soil System, Afshin Gholamy

Open Access Theses & Dissertations

For national economy, it is very important to have a reliable infrastructure. Because of this, all over the world, new roads are constantly being built and old roads are being maintained and, if necessary, expanded and/or repaired. Building a good quality road is very expensive, it costs several million dollars per kilometer. It is therefore crucial to make sure that the newly built and newly repaired roads are sufficiently stiff - so that they can withstand the predicted volume of traffic for a sufficient number of years. Current methods of estimating the stiffness are time-consuming and labor-consuming. The most accurate …

Utilization Of Digital Image Correlation Technique In Asphalt Testing, Alejandra Escajeda

Open Access Theses & Dissertations

Over 90% of the roads in the United States are paved with hot mix asphalt (HMA). These asphalt pavements include many mix types, such as permeable friction course (PFC), stone mastic asphalt (SMA) and conventional dense graded mixes. The performance of the HMA is an important factor in pavement design programs used by many departments of transportation. The type of HMA selected not only influences the performance of the pavement structure, but also the pavement's life cycle cost. The performance life of an HMA mix is to be studied further with experimental data in order to contribute and expand on …

Onshore-Offshore Velocity Models North Of The Mendocino Triple Junction In Northern California, Alan Jacquez

Open Access Theses & Dissertations

The Mendocino Triple Junction (MTJ) marks the boundary where the Gorda plate, North American Plate, and Pacific Plate meet, separating the Cascadia subduction zone to the North from transform tectonics of the San Andreas plate boundary. This actively deforming region experiences high seismic activity and young geological features. Here we examine offshore and onshore seismic wide-angle reflection and refraction data north of the MTJ crossing the Cascadia subduction zone from offshore northern California to the Western edge of the Sierra Nevada. We image subsurface structures in this region by creating P-wave velocity models using datasets collected in 1993 to 1994 …

Evaluation Of Commercial Pervaporation Membranes For Desalination Of Saline And Brackish Waters, Andres F. Sanchez

Open Access Theses & Dissertations

Pervaporation is a solution separation method that occurs by vapor transport through a selective membrane. As the need to provide drinking water to the growing population increases, pervaporation has potential merit as an alternative desalination technology, especially for water with very high salinity.

To our knowledge, there are no commercially available pervaporation membranes made specifically for desalination applications. Thus, the membranes PERVAP 4100 and PERVAP 4101 manufactured by DeltaMemAG were tested to evaluate their performance in desalination. Because the driving force in pervaporation is the difference in vapor pressure between the feed side and the permeate side of the membrane, …

Technical Project Management: Union Of Systems Engineering Processes With Project Management Processes, Deyaaldeen M. Abusal

Open Access Theses & Dissertations

Today, most projects in technical fields utilize project management to complete projects as planned, and some of the projects utilize system engineering to cover the project in both technically and commercially. This Thesis investigates the relationship between Project Management (PM) and Systems Engineering (SE) to determine if a suitably professional level of management and level of quality can be achieved. When studying PM and SE separately and make a comparison between both, there is much overlap between these two mature fields. The project could be planned and completed solely by either process. This study combines both fields of Project Management …

Assessment Of Climate Change Impact On Hydraulic Design Procedures Of Bridges, Anjuman Ara Akhter

Open Access Theses & Dissertations

The significant change in climate is evident from the records of increased temperature, changed precipitation pattern, increased frequency of extreme weather events like storms, floods, and so forth. Like other infrastructure highway infrastructures also suffer the consequences of these climate change. Since the hydraulic design of these infrastructures is performed using historical climate data, the designs may not be able to provide services because designs are not considering climate change influence especially in terms of precipitation intensity. This study aims at identifying the most accurate source of climate database that predicts future climate change with less uncertainty and links them …

Evaluation Of Recycled Gypsum Application Dosages To Enhance The Water Infiltration Rate At Water Retention Ponds, Jorge Luis Navarrete

Open Access Theses & Dissertations

The retention ponds play central role for efficient collection, removal, and drainage of rainfall runoff from surrounding streets to minimize flooding and damage. However, low percolating retention ponds may result in an extended ponding of water, abundance bacteria accumulations, mosquito breeding, environmental hazards, among others. The presence of clayey soils and soil sodicity reduces infiltration rates of retention ponds. To enhance the infiltration rate of ponds, it is proposed to use recycled gypsum (RG), as a soil amendment in retention ponds consisting of clayey soils to enhance low infiltration rates.

To evaluate the influence of RG in clayey soils as …

Evaluation Of Brackish Water Desalination By Membrane Capacitive Deionization Systems: Performance Tradeoffs In Salt Removal, Hydraulic Recovery, Charge Efficiency, And Specific Energy Consumption, Oluwaseye Michael Owoseni

Open Access Theses & Dissertations

As potable water demand continues to exceed availability in several regions of the world, alternative water sources such as desalination and direct potable reuse have become of high importance in water sustainability discussions. The conventional desalination technologies include reverse osmosis (RO) and thermal distillation. Major barriers to the applicability of these technologies for desalination include inorganic scaling (RO) and high energy requirements respectively. This research provides an evaluation for the feasibility of Membrane Capacitive Deionization (MCDI), which is a technology gaining interest due to its theoretically low energy requirements for brackish water (less than 3 g/L) desalination. The motivation for …

Exploring The Effects Of Zinc Nanoparticle Concentration, Antioxidant, And Media On Cilantro (Coriandrum Sativum), And Radish (Raphanus Sativus) Plants Growth, Venkata Laxma Reddy Pullagurala

Open Access Theses & Dissertations

Engineered nanomaterials (ENMs) have proven to be one of the emerging chemicals of concern in the contemporary times. Soil acts as one of the major sinks of these ENMs. Reports have shown that ENMs have varied effects on soil biota. Particularly, their effects on plants are inconsistent. Amongst these ENMs, ZnO nanoparticles (nZnO) are the fourth largest raw materials in the nanotechnology industry. Globally, it is estimated that around 34,000 tons of n ZnO are utilized per year. The nZnO exposure on terrestrial plants yielded both beneficial as well as detrimental effects. Recently, there is an emerging evidence about the …

Evaluation Of Orthophosphate Based Corrosion Inhibitors In Treated Water For El Paso Region, Francisco Solis Jr

Open Access Theses & Dissertations

Corrosion is an electrochemical phenomenon that involves the deterioration of a metal by the reaction of itself with its surrounding environment. One of the greatest issues for water utilities around the country is to keep the water quality safe. Corrosion can affect the quality of the water that we use on a daily basis by adding a bad taste, increasing the concentration of heavy metals, and allowing outside contaminants to enter the distribution system. The use of phosphate based corrosion inhibitors was tested in two different metals: iron and copper. The phosphate in the inhibitors react with the calcium in …

Investigating Early Age Behavior Of Portland Cement Concrete In Arid Regions, Evan Wolf

Open Access Theses & Dissertations

The early-age behavior and properties of portland cement concrete change rapidly over time as a result of the hydration process. Comprised of a series of chemical reactions, this process accelerates nonlinearly with the curing temperature. Gaining knowledge and understanding of the phases of the hydration process (i.e., dormant, setting, and hardening) plays an important role in the timely opening of roads, resuming of construction, and achieving long-term performance. Standard tests such as ASTM C403 arbitrarily define the time of initial and final setting of concrete. Despite decades of studies concerning setting times, actual predictions still span hours, while the quality …

Influence Of Mix Design Parameters On Performance Of Balanced Asphalt Mixtures, Luiza Helena Barros

Open Access Theses & Dissertations

With the popularity of the Balanced Mix Design (BMD) concept, the need for performance tests that can reliably evaluate the cracking and rutting potentials of asphalt concrete (AC) mixes has become more critical. A great deal of effort has been focused on incorporating test methods that can potentially improve the current AC mix-design processes and consequently screen underperforming AC mixes. However, the influence of mix design parameters on the performanceof BMD mixes that provide pavement engineers and designers with thorough guidelines and a reliable and consistent test protocol has not been extensively documented.

This Thesis presents an experimental evaluation of …

Assessing Corrosivity Of Galvanized Soil Reinforcements From Electrochemical Tests, Diana Alejandra Cabrera

Open Access Theses & Dissertations

The accurate estimation of the service lives of mechanically stabilized earth (MSE) walls requires a proper evaluation of the corrosion potential through electrochemical test methods. Robust field tests are required to assess the corrosivity of galvanized metal used in MSE walls. To simulate an environment similar to an MSE wall, cylindrical soil specimens about 12 in. (300 mm) in diameter and 10 in. (250 mm) in height were constructed. For every specimen, two instruments were used. The first instrument measured the polarization resistance corrosion tests carried out on galvanized strips and meshes, as well as epoxy-coated rebars. The second instrument …

Optimization For The Allocation Of Funds For Pavement Maintenance In Pavement Management Systems, Armando Ramirez

Open Access Theses & Dissertations

Pavement maintenance and rehabilitation are critical and costly elements for highway agencies. A challenge for transportation agencies is to preserve roadways in an appropriate condition and extend the pavement service life while maintaining the safety and satisfaction of its users, and maximize the benefits obtained by the repair investments. Pavement maintenance programming is increasing in complexity due to limited resources and increments in traffic and population. Management decisions are usually based on personal judgment by pavement managers and sometimes those decisions are not even supported by previous experience. Research shows that optimization methods can produce significant benefits when transportation agencies …

Multi-State Multi-Objective Reliability Analysis Of Renewable Energy Systems, Luis Ramirez

Open Access Theses & Dissertations

This work presents a new multi-objective evolutionary algorithm (MOEA), capable of obtaining a system's reliability while considering other objectives that concurrently need to be optimized. The algorithm is applied in two different case studies. One of the problems considers a multi-state, multi-objective renewable energy system which tries to find a configuration between solar panels and wind turbines that maximizes the system's reliability of achieving specific energy demand, while also minimizes the purchasing cost of the system. The second case study analyzes a flexible manufacturing system that contains different machines that can perform different functions. The primary objective is to obtain …

A Quality Control Performance-Based Methodology For Pavement Management Systems, Edgar Daniel Rodriguez Velasquez

Open Access Theses & Dissertations

Transportation Asset Management is a decision-making process, which allocates available resources for operating, maintaining, enhancing, and expanding transportation infrastructure while considering its entire life cycle. Transportation infrastructure includes different types of assets and pavements are one of the main assets due to its social, economic, and environmental impacts to society. Transportation agencies implement Pavement Management Systems to support the pavement management process. While implementing and operating a Pavement Management System, one of the costliest procedures is collecting pavement condition data from the field. Good quality for pavement condition data is required to select the right preservation treatments, estimate the associated …

Evaluation Of Powdered Activated Carbon For Control Of Taste And Odors Caused By Geosmin, Anthony Joe Rodriguez

Open Access Theses & Dissertations

The primary sources of taste and odor problems associated with surface water supplies spawn from algae and bacterial blooms that secrete odorous chemicals such as Geosmin and MIB. These musty, odorous, organic compounds are usually detectable by the human nose at concentrations of 5 to 10 ppt and can create considerable concern by consumers that can lead to complaints and misconceptions of odors as a water quality problem. Typically, since chemical or ozone treatment can be costly, activated carbon (powdered or granular) is generally employed in the process of removing organic compounds, such as Geosmin and MIB. The research presented …

Understanding The Consequences And Costs Of Climate Change On Texas Pavements, Megha Sharma

Open Access Theses & Dissertations

Over the several centuries, the global temperatures have been rising, and the rate of rising in temperature has increased significantly in the last century. The increase in temperature and precipitation can substantially influence performance life of pavements because of their continuous exposure to climate. The climate parameters like temperature and precipitation are considered in the pavement design to reflect the influence of climate factors on the performance of the pavements. Currently, designers use the historical weather patterns while designing pavements. Since the climate is changing, the estimated service life of the pavement will be reduced significantly if the historical data …

Effects Of Gradation And Moisture Content On Resistivity Of Mechanically Stabilized Earth Wall Backfill Materials, Jose Luis Arciniega

Open Access Theses & Dissertations

The service life of mechanically stabilized earth (MSE) walls depends on the corrosion rate of the metallic reinforcement used in their construction. The resistivity of the backfill aggregates needs to be measured accurately in order to estimate realistically the corrosion rate of the reinforcement. Resistivity testing is usually performed using the traditional soil box on the portion of the aggregates that passes a No. 10 or No. 8 sieve to either select or reject the backfill. For a more reasonable characterization of the corrosivity of coarse backfills, it is desirable to use their actual gradations. To that end, several resistivity …