Civil Engineering Commons^™

Assessing Simulated Transmissivity In Numerical Flow Models Of Complex Hydrogeology, Afan Tarar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Accurately extracting a meaningful transmissivity, a target value within one order of magnitude of field estimates, in numerical models poses a significant challenge when modeling complex groundwater systems. Aquifer transmissivity is directly proportional to the aquifer thickness and the estimated aquifer hydraulic conductivity. In complex geologic conditions (especially in fractured systems) with multiple heterogeneous and anisotropic hydrogeologic units, transmissivity can vary over several orders of magnitude.

To extract a meaningful value of transmissivity from a numerical model, a simple five-layer MODFLOW model was constructed. Each layer in the model was assigned a fixed hydraulic conductivity and thickness. The model simulates …

Multi-Resolution Spatio-Temporal Change Analyses Of Hydro-Climatological Variables In Association With Large-Scale Oceanic-Atmospheric Climate Signals, Kazi Ali Tamaddun

UNLV Theses, Dissertations, Professional Papers, and Capstones

The primary objective of the work presented in this dissertation was to evaluate the change patterns, i.e., a gradual change known as the trend, and an abrupt change known as the shift, of multiple hydro-climatological variables, namely, streamflow, snow water equivalent (SWE), temperature, precipitation, and potential evapotranspiration (PET), in association with the large-scale oceanic-atmospheric climate signals. Moreover, both observed datasets and modeled simulations were used to evaluate such change patterns to assess the efficacy of the modeled datasets in emulating the observed trends and shifts under the influence of uncertainties and inconsistencies. A secondary objective of this study was to …

A Unified Risk-Based Framework For Assessing Sustainability And Resiliency Of Civil Infrastructure, Thomas Adam Robbins

Boise State University Theses and Dissertations

As of February 2019, the National Aeronautics and Space Administration (NASA) has reported since 1880 the average global temperature has increased 1°C, with the warmest year on record being 2016. As the years continue to pass, it is becoming more evident that climate change is occurring, which is known to be a catalyst for climatic weather events. Statistically speaking, these events are more prevalent, and catastrophic exemplified as hurricanes, earthquakes, flooding, and fires. In addition to the increase of potentially catastrophic events, society as a whole has become more conscientious in the use and preservation of natural resources, waste generation, …

Sustainable Ground Improvement Method Using Recycled Plastic Pins, Md Nur Basit Zaman

Civil Engineering Dissertations - Archive

Failure of civil engineering infrastructures due to insufficient bearing and shearing capacity of the unsuitable foundation soil is a common problem in the area of North Texas which results in significant maintenance issues for the Texas Department of Transportation (TxDOT). The major concerns regarding construction over such foundation soil includes excessive total and differential settlement of footing resulting in bearing capacity failure and sliding failure of the Mechanically Stabilized Earth (MSE) retaining structure due to inadequate shear resistance. The most common technique followed by TxDOT to counter such problem is to remove and replace the existing soil with appropriate fill …

A Microfluidic Platform For The Simultaneous Quantification Of Methanogen Populations In Anaerobic Digestion Processes, Prince Peter Mathai, Hannah M. Dunn, Kaushik Venkiteshwaran, Daniel Zitomer, James Maki, Satoshi Ishii, Michael J. Sadowsky

Civil and Environmental Engineering Faculty Research and Publications

Methanogens are a diverse group of archaea that play a critical role in the global carbon cycle. The lack of appropriate molecular tools to simultaneously quantify numerous methanogenic taxa, however, has largely limited our ability to study these communities in a wide variety of habitats, such as anaerobic digesters (ADs). In this study, 34 probe-based quantitative PCR (qPCR) assays were designed to target all known methanogenic genera within the archaeal phylum Euryarchaeota. These qPCR assays were adapted to a high-throughput microfluidic platform, which allowed for the simultaneous detection and absolute quantification of numerous taxa in a single run. The …

Outdoor Education Center Concept Site Master Plan And Improvements As Designed By Wingineers, Christina Thibodeau

Honors Program: Senior Projects (Public)

This thesis builds on a basis of four years of engineering education to produce a final project for the capstone course. The idea behind this project was to provide a workable master plan and conceptual site improvements for a real application, the Outdoor Education Center in east Lincoln, Nebraska. The Boy Scouts of America Cornhusker Council and the University of Nebraska – Lincoln Department of Civil Engineering have cooperated throughout the Senior Design capstone course to make this possible for the students involved.

Bs News May/June

Building Services Engineering

No abstract provided.

Design And Analysis Of Fiber Reinforced Concrete Structure For Transportation Infrastructures, Salam Adil Mutlag Wtaife

Theses and Dissertations

Concrete is one of the most popular materials in superstructures (buildings), substructures (foundation) and infrastructure facilities (bridges, pavements, and tunnels). However, concrete is a brittle material that cracks easily under tension. Fiber may be used as reinforcement to impede the concrete from cracking as well as to increase the concrete flexural strength. Nevertheless, current design codes do not include this design enhancement. Furthermore, there are discrepancies in the design methodology concerning the inclusion of discrete fibers in concrete structures. Therefore; there is a need to develop new analysis methodology and design methodology for fiber reinforced concrete (FRC) and fiber reinforced …

Lateral And Torsional Seismic Vibration Control For Torsionally Irregular Buildings, Osman Akyürek

Theses and Dissertations

During strong earthquakes or wind gusts, it is likely that buildings with torsional irregularity in the plan have an can be seriously damaged, partially collapsed or fully collapsed. This is because Torsionally Irregular Buildings (TIBs) may have significant aerodynamic torsion loads that increase the eccentricity between the center of mass and the center of rigidity, especially in dominant torsion modes. For this reason, torsion leads to excessive increase in lateral motions when dynamic loads excite the buildings. Torsional irregularity is one of the main failure causes during strong dynamic excitations due to earthquakes or wind gusts. Ignoring torsional irregularity in …

Damping Coefficient Sensitivity Analysis Of High Rebound Soils In Florida, Aline Franqui

Theses and Dissertations

The dynamic response of soils is related to a damping factor, which represents the energy absorbed by the soil as the pile moves. Certain blends of fine sands, silts and clays are producing pile rebound during driving. For that reason, the objective of this thesis is to conduct a damping coefficient sensitivity analysis of high rebound soils in Florida. Forty cyclic triaxial tests from six sites in Central and Northern Florida were analyzed to evaluate damping. Two approaches were used, one based on the change in stress over time and a second based on the viscous energy absorbed per cycle. …

Effect Of Industry Clusters And Commodity Flow Characteristics On The Selection Of Freight Transportation Modes In The United States With Advanced Econometric Approaches, Taleb Eissa Ali Eissa

Theses and Dissertations

Mode choice is an important strategic decision for shippers to carry commodities efficiently. Freight mode-choice is an important activity to develop a successful freight transportation business in the private sector and to plan for economically consistent freight transportation infrastructures in the public sector. Freight activities result from the complex interactions between different economic agents, but these relationships are commonly relaxed to account for three major agents: shippers, carriers and receivers. Furthermore, the behavior of freight choice is commonly not concentrated in one agent, but rather is divided jointly over multiple individuals and firms in a logistics process, each component of …

Taxonomy And Abstraction Of The On-Demand Mobility Aviation System For Smart Cities, Wancheng Dai

Theses and Dissertations

The on-demand mobility aviation system is a new paradigm providing aircraft-based point-to-point transportation services to travelers in urban and suburban areas. Many consider it as the next revolution in intelligent transportation systems. Since it does not require pre-scheduling and vehicles travel at high speed, travel times are dramatically decreased, which overcomes issues of the current ground transportation system, improves travel times and level of service, increases productivity and creates new business models. Likewise, it is envisioned to generate positive environmental outcomes. Since this is a new and unique mode of intelligent transportation, few is known about its potential success and …

Structural Design Guidelines For Pervious Concrete Pavements, April Smith

Civil Engineering Undergraduate Honors Theses

Pervious pavements have gained popularity in recent years as the transportation industry focuses on sustainability and environmental impact. This research investigated the structural design of pervious concrete pavements. There is no standard design method; therefore, the goal was to lessen ambiguity surrounding the use of pervious concrete for pavement structures. By characterization of the rigid pavement design equation from the 1993 AASHTO Structural Design Guide for Design of Pavement Structures through laboratory exploration and review of existing literature, a guide was created to assist engineers in the design of pervious concrete pavements.

Asphalt Concrete As A Flooring Material, Aleinys Villarreal

Civil Engineering Undergraduate Honors Theses

The need for having a good quality flooring has become something very important in order to enhance people’s spaces and living lifestyle. Some of the most common tile materials are cork, vinyl, concrete, and ceramic. While these four materials mentioned before are still capable materials, asphalt concrete has a distinct pattern that may be an attractive alternative to the standard tile types. To try and find solutions to these problems and give people another material option, asphalt concrete was evaluated as a flooring material.

The reason why asphalt concrete could have this new application is based on the outstanding properties …

The Influence Of Citric Acid On Setting Time And Temperature Behavior Of Calcium Sulfoaluminate-Belite Cement, Edgar Soriano

Civil Engineering Undergraduate Honors Theses

Today the need to opt for alternative cementitious materials is growing due to environmental reasons and construction time frames that portland cement cannot always satisfy. Calcium Sulfoaluminate (CSA) cements are a strong candidate to supplement or replace portland cement in the construction field for certain applications. In the United States, CSA cement has been limited mostly to pavement repairs because of its rapid initial setting time. The chemical compound responsible for this phenomenon is the alumina. This compound and sulfate are present in larger proportions compared to portland cement. The purpose of this research is to study how the use …

Tension Splitting Strength Of Bcsa Concrete Cylinders, Andrew Steven Deschenes

Civil Engineering Undergraduate Honors Theses

The focus of this research was to compare the tension splitting strength (TSS) of belitic calcium sufloaluminate (BCSA) cement concrete to tensile strength predicted by the American Concrete Institute (ACI) and to similarly proportioned portland cement (PC) concrete. BCSA is a rapid-setting cement with higher early strength, higher ettringite content, and lower calcium silicate hydrate (C-S-H) content than PC. PC and BCSA cement concrete cylinders were broken at different ages in both uniaxial compression and TSS. It was found that BCSA had a similar TSS to both the ACI prediction and PC TSS, but the results require further testing for …

Biofiltration Of Volatile Organic Compounds Emitted At Ethanol Plants, Christopher Arthur Duerschner

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Ethanol manufacturing is an important and growing sector in the biofuels marketplace. At ethanol plants, the control of volatile organic compound containing emissions from fermentation tanks and distillers dried grains with solubles driers is accomplished through the use of air scrubbers and regenerative thermal oxidizers. The operation of these control units imposes substantial operating costs for the ethanol plant. Biotrickling filters have the ability to replace scrubbers and regenerative thermal oxidizers resulting in significant economic and environmental benefits. Two biotrickling filters were operated in parallel under acetaldehyde loadings ranging from 4 to 136 gm^-3hr^-1. To examine …

Utilization Of Remote Sensing Data For Estimation Of The Groundwater Storage Variation, Gaurang Mistry

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is the most extracted raw material, with an average withdrawal rate of 982 km3 per year, where 70 percent of the total groundwater withdrawn is used for agriculture globally (Margat & van der Gun, 2013). With climate change and increased water demands in recent years, monitoring the changes in the groundwater storage is of the utmost importance. This thesis presents an analysis that determines the rates, trends, and directions where groundwater storage is going in Pakistan. It also correlates fluctuations in groundwater storage with variations in precipitation and agricultural productivity in the country. The overall objectives of this thesis …

Wildfire Smoke: Trends, Challenges, Unknowns, And Human Response, Mariah Dawn Fowler

Boise State University Theses and Dissertations

Wildfire smoke is a growing threat to human livelihood in the Western United States. The economic and the health burden of smoke is accelerating in response to a growing fire season and escalating fire activity. This study first evaluates the trends in air quality over Boise, Idaho and the entire Northwest (and Montana) to assess the impacts of wildfire smoke in the region. The Mann-Kendall trend analysis shows that there is a statistically significant trend in the average and maximum air quality index (AQI) during the fire season (July-August-September) in the Boise area. The AQI shows a decreasing trend, although …

Modeling Of Hurricane-Induced Interior And Contents Damage And Associated Time-Related Expenses To Residential Buildings, Roberto Vicente Silva De Abreu

Theses and Dissertations

Hurricanes are a main cause of economic losses in many parts of the world, including the state of Florida. They affect the exterior, interior, and the contents of residential buildings. The damage of the interior can be as much as half of the total damage, but the estimation of the interior damage is still somewhat crude. Most damage models estimate interior damage as a percentage of the exterior damage, or through simple relationships, that relate the height of water ingress in the building to the interior damage. The current version of the Commercial Low-Rise Residential vulnerability model (CLR) of the …