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Full-Text Articles in Civil and Environmental Engineering

Development Of An Algorithm For Satellite Remote Sensing Of Sea And Lake Ice, Peter Dorofy Dec 2017

Development Of An Algorithm For Satellite Remote Sensing Of Sea And Lake Ice, Peter Dorofy

Theses and Dissertations

Satellite remote sensing of snow and ice has a long history. The traditional method for many snow and ice detection algorithms has been the use of the Normalized Difference Snow Index (NDSI). This manuscript is composed of two parts. Chapter 1, Development of a Mid-Infrared Sea and Lake Ice Index (MISI) using the GOES Imager, discusses the desirability, development, and implementation of alternative index for an ice detection algorithm, application of the algorithm to the detection of lake ice, and qualitative validation against other ice mapping products; such as, the Ice Mapping System (IMS). Chapter 2, Application of Dynamic Threshold …

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Project Management: Skills, Tools, And Knowledge Construction Professionals Consider Important For Keeping Projects On Schedule, Lyle Scott Davies Dec 2017

Project Management: Skills, Tools, And Knowledge Construction Professionals Consider Important For Keeping Projects On Schedule, Lyle Scott Davies

Theses and Dissertations

Project managers have a major role in the construction and completion of projects. Much of their work consists of reviewing, clarifying, and coordinating information required by the field management and subcontractors performing the work on the job site. The assistance they give with the transfer of information helps with successfully completing projects. For many people, the largest indicator that a project was successful is that construction activities were completed on schedule. While finishing on schedule may be the primary focus of those involved with construction activities, projects still struggle to finish on time. The purpose of this study is to …

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Analysis Of Safety Impacts Of Access Management Alternatives Using The Surrogate Safety Assessment Model, Kyung Min Kim Dec 2017

Analysis Of Safety Impacts Of Access Management Alternatives Using The Surrogate Safety Assessment Model, Kyung Min Kim

Theses and Dissertations

In a traditional safety impact analysis, it is necessary to have crash data on existing roadway conditions in the field and a few years must pass before accumulating reliable crash data. This is a time-consuming approach and there remains uncertainty in the crash data due to the random nature of crash occurrences. The Surrogate Safety Assessment Model (SSAM) was developed for resolving these issues. With SSAM, a conflict analysis is performed in a simulated environment. A planned improvement alternative under study is modeled and no physical installation of the alternative is needed. Hence, the method using a simulation software along …

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Current State Of Practice Associated With The Use Of Building Information Modeling (Bim) In The Custom Home Building Industry, William Noble Smith Dec 2017

Current State Of Practice Associated With The Use Of Building Information Modeling (Bim) In The Custom Home Building Industry, William Noble Smith

Theses and Dissertations

Building Information Modeling (BIM) has entered the construction industry and has permeated the commercial sector. Research is continually performed to expand the capabilities and applications within the industry. However, research has historically been mostly limited to the commercial sector and has seen little expansion to other sectors of the industry including the residential sector. The potential cause for this may be the limited number of industry professionals who utilize the software to the benefit of their companies. The focus of this study was specifically the custom home building sector of residential construction in the United States because of the unique …

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Reliability Of Feqdrain For Modeling Performance Of Sand Treated With Large-Diameter Prefabricated Drains For Liquefaction Mitigation, Travis Hatch Meservy Dec 2017

Reliability Of Feqdrain For Modeling Performance Of Sand Treated With Large-Diameter Prefabricated Drains For Liquefaction Mitigation, Travis Hatch Meservy

Theses and Dissertations

Finite element modeling of laminar shear box testing that consisted of loose sand treated with large diameter prefabricated vertical drains (PVDs), was performed. The objective of the modeling was to evaluate the reliability of the computer program FEQDrain for predicting excess pore pressure ratios (Ru) at sites treated with prefabricated drains. FEQDrain was found to be capable of successfully modeling measured excess pore pressure ratio time histories from the laminar shear box experiment, as long as an appropriate combination of €˜number of equivalent cycles and €˜shaking duration was chosen, and sensitive parameters were in the range of measured values. Hydraulic …

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An Experimental Comparison Between Fine Aggregate And Quarry Fines Based On Mortar Block Strength, Karthik Boregowda Nov 2017

An Experimental Comparison Between Fine Aggregate And Quarry Fines Based On Mortar Block Strength, Karthik Boregowda

Theses and Dissertations

The strength properties of mortar mainly depend on the materials used for casting. Each material has its own importance for cement mortar strength. In this research, quarry fines, a waste by-product, replaced a portion of fine aggregate in mortar. This research focuses on compressive strength of cement mortar using American Society for Testing and Materials standards. The specimens were cast in standard 2”x 2” inch molds. The compressive strength of blocks with replacement of fine aggregate by quarry fines at 15%, 25%, 30%, and 50% was tested at 7, 14 and 28 days of curing. The results were compared with …

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Pull-Out Strength Of Fiberglass/Epoxy Composite Rebarfabricated On A Three-Dimensional Braiding Machine, Tarisai Machanzi Nov 2017

Pull-Out Strength Of Fiberglass/Epoxy Composite Rebarfabricated On A Three-Dimensional Braiding Machine, Tarisai Machanzi

Theses and Dissertations

The objective of this research was to explore and demonstrate the production andperformance of fiber-reinforced polymer (FRP) rebar manufactured on a continuous threedimensionalbraiding machine for use as reinforcement in concrete structures. Differentconfigurations of fiberglass/epoxy composite cylindrical rebar rods were manufactured,embedded in concrete, and tested in axial tension to identify the relationships betweenmanufacturing parameters and tensile pull-out strength of the rebar. The strength of the bondbetween concrete and FRP rebar was investigated using the pull-out test detailed by ACI 440.3R-12. The rebar was a No. 4 size and produced by combining multiple tows of fiberglass/epoxyprepreg to form the core of cylindrical …

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The State Of Bim-Based Quantity Take-Off Implementation Among Commercial General Contractors, Morgan Christian Tagg Nov 2017

The State Of Bim-Based Quantity Take-Off Implementation Among Commercial General Contractors, Morgan Christian Tagg

Theses and Dissertations

Building Information Modeling (BIM) plays an important role in today's construction industry. Models are tools that help stakeholders communicate, visualize building geometry, perform trade coordination and clash detection among others. A less popular aspect of BIM that shows high potential is the quantity take-off (QTO) feature. Yet, its implementation among commercial general contractors (GC) has not received as much attention. The purpose of this study was to identify how the BIM QTO features were being implemented among commercial general contractors, what challenges they faced and how they worked to overcome those challenges. Through a three-step process including semi structured interviews …

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Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Lateral Spread Displacements Using The Cone Penetration Test, Tyler Blaine Coutu Oct 2017

Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Lateral Spread Displacements Using The Cone Penetration Test, Tyler Blaine Coutu

Theses and Dissertations

Liquefaction-induced lateral spread displacements cause severe damage to infrastructure, resulting in large economic losses in affected regions. Predicting lateral spread displacements is an important aspect in any seismic analysis and design, and many different methods have been developed to accurately estimate these displacements. However, the inherent uncertainty in predicting seismic events, including the extent of liquefaction and its effects, makes it difficult to accurately estimate lateral spread displacements. Current conventional methods of predicting lateral spread displacements do not completely account for uncertainty, unlike a performance-based earthquake engineering (PBEE) approach that accounts for the all inherent uncertainty in seismic design. The …

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An Investigation Into Isogeometric Blended Shells, David Scott Willoughby Oct 2017

An Investigation Into Isogeometric Blended Shells, David Scott Willoughby

Theses and Dissertations

Improvements to isogeometric blended shells are introduced which blend traditional Reissner-Mindlin shells, and Kirchhoff-Love shells, with an exact interpolation of the shell director increment. A gradient extraction operator is introduced which allows derivatives of basis functions to be exactly expressed as a linear combination of the basis functions themselves. Several benchmarks are investigated and the new blended shell is compared with different shell elements in ABAQUS and NASTRAN. In addition, the effect of different quadrature schemes is included in the comparisons. The new isogeometric blended shell performs comparably in some benchmarks, and even outperforms commercial shell finite elements in some …

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Characterization Of Jet Fuel Combustion Emissions During A C-130 Aeromedical Evacuation Engines Running Onload, Michelle L. Page Sep 2017

Characterization Of Jet Fuel Combustion Emissions During A C-130 Aeromedical Evacuation Engines Running Onload, Michelle L. Page

Theses and Dissertations

The purpose of this research was to characterize jet fuel combustion emissions (JFCE) in an occupational setting. Prior research demonstrated that aircraft emit hazardous species, especially at engine start-up and ground idle. Complaints of eye, nose, and throat irritation from occupational exposures near aircraft exist. In this study JFCE were tested during an aeromedical evacuation engines running patient onload (ERO) on a C-130 Hercules at the 179th Airlift Wing, Mansfield-Lahm Air National Guard. Ultrafine particles, VOC, formaldehyde, carbon monoxide (CO), sulfuric acid, and metals were sampled simultaneously in approximate crew and patient breathing zones. Testing methods were portable condensation …

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Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs Sep 2017

Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs

Theses and Dissertations

This work examined ultraviolet (UV) light emitting diodes (LED) and hydrogen peroxide in an advanced oxidation process in support of a USAF installation net zero water initiative. A UV LED reactor was used for degradation of soluble organic chemicals. There were linear relationships between input drive current, optical output power, and first order degradation rate constants. When drive current was varied, first order degradation rates depended on chemical identities and the drive current. When molar peroxide ratios were varied, kinetic profiles revealed peroxide-limited or radical-scavenged phenomena. Molar absorptivity helped explain the complexity of chemical removal profiles. Degradation kinetics were used …

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Large-Scale Testing Of Low-Strength Cellular Concrete For Skewed Bridge Abutments, Tyler Kirk Remund Sep 2017

Large-Scale Testing Of Low-Strength Cellular Concrete For Skewed Bridge Abutments, Tyler Kirk Remund

Theses and Dissertations

Low-strength cellular concrete consists of a cement slurry that is aerated prior to placement. It remains a largely untested material with properties somewhere between those of soil, geofoam, and typical controlled low-strength material (CLSM). The benefits of using this material include its low density, ease of placement, and ability to self-compact. Although the basic laboratory properties of this material have been investigated, little information exists about the performance of this material in the field, much less the passive resistance behavior of this material in the field.In order to evaluate the use of cellular concrete as a backfill material behind bridge …

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Vulnerability Model Of Residential Structures Subject To Hurricane Induced Wind, Surge And Inundation, Mohammad Baradaranshoraka Sep 2017

Vulnerability Model Of Residential Structures Subject To Hurricane Induced Wind, Surge And Inundation, Mohammad Baradaranshoraka

Theses and Dissertations

Annualized hurricane-related losses to the built environment in the United States are in the billions of dollars. According to the National Oceanic and Atmospheric Administration, in 2010 39% of the United States population, or 123.3 million inhabitants, lived in a coastal county. This population is expected to increase by 8% from 2010 to 2020. The majority of these people live in buildings prone to hurricanes. The hurricanes can result in wind damage (due to high wind and/or wind-driven rain infiltration) and water damage (due to storm surge and waves or freshwater flooding) to the building and its contents, which are …

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Crack Healing In 304l Stainless Steel Using Additive Manufacturing And Friction Stir Processing (Fsp), Cameron Scott Gygi Aug 2017

Crack Healing In 304l Stainless Steel Using Additive Manufacturing And Friction Stir Processing (Fsp), Cameron Scott Gygi

Theses and Dissertations

Continuing an investigation on using FSP to heal stress corrosion cracks (SCC) in welds on nuclear reactors, this study seeks to use AM in addition to FSP to aid crack repair. Previous studies address that current repair technology on nuclear reactors involves the use of TIG welding which can allow helium atoms to aggregate and form voids at the grain boundaries. This weakens the material and renders the repair ineffective. Another previous study evaluated the effectiveness of FSP alone in repairing SCC which did have defects depending on the parameters used during FSP. This study evaluated the use of AM …

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Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez Aug 2017

Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez

Theses and Dissertations

Traditionally, water quality modelling has focused on modelling individual water bodies. However, water quality management problems must be analyzed at the larger scale to include influences from various water bodies that are interconnected. This paper provides a study on the hydrologic and quality transportation calculation by developing a hydrodynamic (unsteady state) channel routing model using a water-balanced approach. A one dimension Lagrangian river model was developed and applied to the 210 plus miles for the lower Rio Grande River Basin from the Falcon Dam to the head water of Brownsville that pours onto the Gulf of Mexico. This model can …

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Performance-Based Liquefaction Triggering Analyses With Two Liquefaction Models Using The Cone Penetration Test, Alex Michael Arndt Aug 2017

Performance-Based Liquefaction Triggering Analyses With Two Liquefaction Models Using The Cone Penetration Test, Alex Michael Arndt

Theses and Dissertations

This study examines the use of performance-based engineering in earthquake liquefaction hazard analysis with Cone Penetration Test data (CPT). This work builds upon previous research involving performance-based liquefaction analysis with the Standard Penetration Test (SPT). Two new performance-based liquefaction triggering models are presented herein. The two models used in this liquefaction analysis are modified from the case-history based probabilistic models proposed by Ku et al. (2012) and Boulanger and Idriss (2014). Using these models, a comparison is made between the performance-based method and the conventional pseudo-probabilistic method. This comparison uses the 2014 USGS probabilistic seismic hazard models for both methods. …

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Blending And Mixed Variational Principles To Overcome Locking Phenomena In Isogeometric Beams, Kyle Dennis Richardson Jul 2017

Blending And Mixed Variational Principles To Overcome Locking Phenomena In Isogeometric Beams, Kyle Dennis Richardson

Theses and Dissertations

Two methods for overcoming locking phenomena in isogeometric beams are presented. The first method blends the rotation of a Timoshenko beam with the rotation of a Bernoulli beam to produce realistic displacements in straight beams. The second method uses mixed variational principles, specifically the Hu-Washizu Principle, to produce realistic displacements as well as realistic strains without post-processing.

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Quick Shear Testing Of Aggregate Base Materials Stabilized With Geogrid, Rawley Jack Selk Jul 2017

Quick Shear Testing Of Aggregate Base Materials Stabilized With Geogrid, Rawley Jack Selk

Theses and Dissertations

The objective of this research was to apply a previously recommended laboratory testing protocol to specific aggregate base materials that are also the subject of ongoing full-scale field testing. The scope of this research involved three aggregate base materials selected from three sites where full-scale field testing programs have been established. The first and second field sites included five different geogrid types, categorized as either biaxial or triaxial, in a singlelayer configuration, while the third site included only the triaxial geogrid type in either a singleor double-layer configuration. Geogrid-stabilized and unstabilized control specimens were evaluated using the American Association of …

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Full-Scale Testing Of Blast-Induced Liquefaction Downdrag On Driven Piles In Sand, Luke Ian Kevan Jul 2017

Full-Scale Testing Of Blast-Induced Liquefaction Downdrag On Driven Piles In Sand, Luke Ian Kevan

Theses and Dissertations

Deep foundations such as driven piles are often used to bypass liquefiable layers of soil and bear on more competent strata. When liquefaction occurs, the skin friction around the deep foundation goes to zero in the liquefiable layer. As the pore pressures dissipate, the soil settles. As the soil settles, negative skin friction develops owing to the downward movement of the soil surrounding the pile. To investigate the magnitude of the skin friction along the shaft three driven piles, an H-pile, a closed end pipe pile, and a concrete square pile, were instrumented and used to measure soil induced load …

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Development Of A Simplified Performance-Based Procedure For The Assessment Of Liquefaction-Induced Settlements Using Liquefaction Loading Maps, Braden Michael Error Jul 2017

Development Of A Simplified Performance-Based Procedure For The Assessment Of Liquefaction-Induced Settlements Using Liquefaction Loading Maps, Braden Michael Error

Theses and Dissertations

Liquefaction-induced settlement can cause extensive damage to infrastructure. Quantifying the amount of settlement that may occur after an earthquake is crucial to seismic design. The Pacific Earthquake Engineering Research (PEER) Center developed performance-based earthquake engineering (PBEE) as a probabilistic framework to characterize the risks associated with a seismic event. When applied to liquefaction-induced settlement, the PBEE framework provides a more complete and accurate representation of liquefaction hazard than other more conventional evaluation methods. Performance-based engineering is not widely used in practice, however, due to its complexity. In an attempt to make performance-based engineering methods more accessible to engineers for routine …

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How The Choice Of Bed Material Load Equations And Flow Duration Curves Impacts Estimates Of Effective Discharge, Michael James Cope Jun 2017

How The Choice Of Bed Material Load Equations And Flow Duration Curves Impacts Estimates Of Effective Discharge, Michael James Cope

Theses and Dissertations

The purpose of this study is to analyze how estimates of an important geomorphic parameter, effective discharge, are impacted by the choice of bed material load equations and flow duration curves (FDCs). The Yang (1979), Brownlie (1981), and Pagosa equations developed by Rosgen (2006) were compared for predicting bed material load. To calculate the bed material load using the Pagosa equations, the bedload and suspended load are calculated separately and the results are added together. To compare the effectiveness of the equations, measured bed material load data from the USGS Open-File Report 89-67 were used. Following the calculations, the equation …

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Development Of A Performance-Based Procedure To Predict Liquefaction-Induced Free-Field Settlements For The Cone Penetration Test, Mikayla Son Hatch Jun 2017

Development Of A Performance-Based Procedure To Predict Liquefaction-Induced Free-Field Settlements For The Cone Penetration Test, Mikayla Son Hatch

Theses and Dissertations

Liquefaction-induced settlements can cause a large economic toll on a region, from severe infrastructural damage, after an earthquake occurs. The ability to predict, and design for, these settlements is crucial to prevent extensive damage. However, the inherent uncertainty involved in predicting seismic events and hazards makes calculating accurate settlement estimations difficult. Currently there are several seismic hazard analysis methods, however, the performance-based earthquake engineering (PBEE) method is becoming the most promising. The PBEE framework was presented by the Pacific Earthquake Engineering Research (PEER) Center. The PEER PBEE framework is a more comprehensive seismic analysis than any past seismic hazard analysis …

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Discrete Element Analysis Of Scb Variability: Asphalt Mixtures, David Saul Renteria May 2017

Discrete Element Analysis Of Scb Variability: Asphalt Mixtures, David Saul Renteria

Theses and Dissertations

The Semi-Circular Bending (SCB) test was modeled using the Discrete Element Method (DEM) implemented in numerical software Particle Flow Code (PFC). The fracture analysis of the SCB was studied using two mixtures gradation, Superpave and Coarse Matrix High Binder. The aggregate phase in the model was achieved by using two-dimensional aggregate images with different angularity indexes. The study of the variability of the SCB extends to the random generation of aggregate particles and air voids in the model, in addition to changing the properties at the interface between the aggregate and mastic phases. Results indicate the strong influence of the …

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Estimation Of Groundwater Loads Into A Coastal Estuary Using Seawat, Antonio S. Berber Jr. May 2017

Estimation Of Groundwater Loads Into A Coastal Estuary Using Seawat, Antonio S. Berber Jr.

Theses and Dissertations

The research of regional groundwater flow is of vital importance at the Indian River Lagoon (IRL) due to the potential contribution groundwater flow has on nutrients into the IRL. If too many nutrients are introduced into the IRL, algal blooms could occur and impact the health of IRL system. The IRL is a coastal estuary located on the east coast of Florida. Submarine groundwater seepages (SGD) and groundwater loads into the IRL were numerically estimated by using SEAWAT, a program designed to simulate variable-density groundwater flow coupled with multi-species solute transport. Models were completed at three different study transects that …

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The Significance Of A High Resolution 2d Hydraulic Model Including Green Infrastructure For Assessment Of Coastal Community Vulnerability And Resilience, Katie M. Miller Apr 2017

The Significance Of A High Resolution 2d Hydraulic Model Including Green Infrastructure For Assessment Of Coastal Community Vulnerability And Resilience, Katie M. Miller

Theses and Dissertations

This paper outlines the development of an enhanced hydraulic flood model that uses a fine-scale grid to analyze significant areas of flooding for improved flood predictions and resiliency planning. This study modeled the extent of Atlantic City and Camden, New Jersey. The capabilities of the model were compared to coarser national models, HAZUS-MH and SLOSH, to understand the significance of fine-scale hydraulic modeling. The results illustrated that the HAZUS and SLOSH models showed gaps in some areas and lacked accuracy due to lower resolution. This paper also describes how these developed models show the impacts of severe storms, and the …

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Evaluating The Impact Of Different Types Of Stabilized Bases On The Overall Performance Of Flexible Pavements, Andrae Anthony Francois Apr 2017

Evaluating The Impact Of Different Types Of Stabilized Bases On The Overall Performance Of Flexible Pavements, Andrae Anthony Francois

Theses and Dissertations

This study was initiated with the aim of evaluating the impact of stabilized and untreated base layers on the performance (i.e., fatigue and rutting) of flexible pavements. Four field sections constructed using stabilized base layers (i.e., bituminous (asphalt emulsion), calcium chloride (CaCl-2), Portland cement, and geogrid stabilized base layers) and a control section constructed using untreated RAP aggregates were analyzed in this study. Falling Weight Deflectometer (FWD) tests were conducted on all the field sections and the collected data was used to backcalculate the elastic moduli for all layers. The influence of the stabilized bases and the untreated RAP base …

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Application Of Ground Penetrating Radar To Highway-Related Problems, Rauf Rejab Hussein Apr 2017

Application Of Ground Penetrating Radar To Highway-Related Problems, Rauf Rejab Hussein

Theses and Dissertations

The Broadway Bridge, constructed in 1923, crosses the Arkansas River in the downtown area of Little Rock, AR and was the main crossing point between Little Rock and North Little Rock. The structural deterioration of the bridge reached a level beyond patch and repair. Accordingly, the Arkansas Highway and Transportation Department (AHTD), in collaboration with the City of Little Rock, allocated the required resources ($98.4M) to demolish and replace the bridge. Due to the age of the bridge site and the limited knowledge of the subsurface utility layout, it became clear that geotechnical work be done in order to map …

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Full-Scale Pavement Testing Of Aggregate Base Material Stabilized With Triaxial Geogrid, Shaun Todd Hilton Apr 2017

Full-Scale Pavement Testing Of Aggregate Base Material Stabilized With Triaxial Geogrid, Shaun Todd Hilton

Theses and Dissertations

The objective of this research was to investigate the structural capacity of aggregate base materials stabilized with triaxial geogrid placed in a full-scale pavement involving control, or unstabilized, sections. Field testing was performed on a roadway in northeastern Utah that was 16 km (10 miles) long and included 10 test sections, seven stabilized sections and three control sections, each having five test locations. The pavement structure was comprised of a hot mix asphalt layer overlying an untreated aggregate base layer of varying thickness, depending on the test section. Except for the control sections, one or two layers of geogrid were …

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Strut-And-Tie Modeling Of Multistory, Partially-Grouted, Concrete Masonry Shear Walls With Openings, Jeffrey Ryan Buxton Apr 2017

Strut-And-Tie Modeling Of Multistory, Partially-Grouted, Concrete Masonry Shear Walls With Openings, Jeffrey Ryan Buxton

Theses and Dissertations

Construction practices are constantly evolving in order to adapt to physical locations and economic conditions. These adaptations may result in more cost-effective designs, but may also come at a cost of strength. In masonry shear walls, it is becoming more common to reduce the amount of grouting from every cell to only those with reinforcement, a practice known as partial-grouting. Partially-grouted masonry responds differently and in a more complex matter to lateral loads as compared to fully-grouted masonry. The response is made even more complex by wall discontinuities in the form of openings. The main objective of this study is …

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