Civil and Environmental Engineering Commons^™

Prestress Losses In Lightweight Self-Consolidating Concrete, Jared Bymaster

Graduate Theses and Dissertations

While much research has been performed on lightweight concrete and self-consolidating concrete (SCC), the knowledge of prestress losses in lightweight self-consolidating concrete (LWSCC) is still limited. LWSCC has the benefits of increased flowability, reduced placement labor, and decreased shipping cost compared to conventional concrete. This research program included the study of 14 SCC beams cast with expanded clay, expanded shale, and limestone aggregates. Strains in the beams were measured with vibrating-wire strain gages, and the measured prestress losses were compared with current AASHTO methods for calculating prestress losses. The AASHTO approximate method better predicted actual losses than did the AASHTO …

Development Of Mems-Based Corrosion Sensor, Feng Pan

Graduate Theses and Dissertations

This research is to develop a MEMS-based corrosion sensor, which is used for monitoring uniform, galvanic corrosion occurring in infrastructures such as buildings, bridges. The corrosion sensor is made up of the composite of micro/nano metal particles with elastomers. The mechanism of corrosion sensor is based on the mass transport of corrosive species through the sensor matrix. When the metal particles in the matrix corrode, the electrical resistivity of the material increases due to increasing particle resistances or reduction of conducting pathways. The corrosion rate can be monitored by detecting the resistivity change in sensing elements. The life span of …

Performance And Cost Analysis Of A Structured Concrete Thermocline Thermal Energy Storage System, Matt Nicholas Strasser

Graduate Theses and Dissertations

Increasing global energy demands and diminishing fossil fuel resources have raised increased interest in harvesting renewable energy resources. Solar energy is a promising candidate, as sufficient irradiance is incident to the Earth to supply the energy demands of all of its inhabitants. At the utility scale, concentrating solar power (CSP) plants provide the most cost-efficient method of harnessing solar energy for conversion to electrical energy. A major roadblock to the large-scale implementation of CSP plants is the lack of thermal energy storage (TES) that would allow the continued production of electricity during the absence of constant irradiance. Sensible heat TES …

Comprehensive Drainage Study Of The Upper Reach Of College Branch In Fayetteville, Arkansas, Kathryn Lea Mccoy

Graduate Theses and Dissertations

College Branch is a stream with headwaters located on the University of Arkansas campus. The stream flows through much of the west side of campus, gaining discharge and enlarging its channel as it meanders to the south. College Branch has experienced erosion and flooding issues in recent years due to increased urbanization of its watershed and increased runoff volume.

The purpose of this project was to develop a comprehensive drainage study of College Branch on the University of Arkansas campus. Storm runoff and flood flow patterns were evaluated in order to understand the hydraulics and hydrology of the watershed and …

Implementing Conductive Concrete With Photovoltaic Energy To Develop Anti-Icing Airfield Runways, Adam Benjamin Osweiler

Graduate Theses and Dissertations

Snow and ice accumulation on airport runways force airports to cancel or significantly delay flights. Winter weather can also drastically affect airport safety during times of aircraft takeoff and landing. During these times, countless dollars are used to remove snow and return airports to their functional conditions. In this thesis, a conductive concrete solar energy system will be examined in order to prevent snow and ice accumulation. The objective of this research is to implement a conductive concrete overlay system on airport runways in conjunction with photovoltaic energy so that no frost precipitation accumulates on the runway surface.

Applications Of Cobb-Douglas Production Function In Construction Time-Cost Analysis, Ashkan Hassani

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Cobb-Douglas Production Function was widely used in economics and productivity studies across many sectors. The function’s quantitative modeling of resource inputs and production outputs is appealing to the research domain of construction management. In this thesis we explored this function’s application in construction schedule crashing and project risk analysis related to duration of construction projects. Existing research on construction time-cost tradeoff issues rarely explore the origin of the crashing cost which is defined as the cost needed to shorten the project to the desired duration. In the existing literature crashing cost function was either assumed without much justification, or came …

Conductive Concrete For Electromagnetic Shielding – Methods For Development And Evaluation, Aaron P. Krause

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

This research investigates the development and evaluation innovative methods for the use of conductive concrete as an electromagnetic shield. New testing methods are developed to determine the best conductive components to use in the design of a concrete mixture for shielding that shows the best promise. The conductive concrete mixture has the potential to provide electromagnetic shielding that is cost-effective in terms of construction, operation, and maintenance compared to conventional approaches. Two testing methods, Small Sample Testing and Large Slab Testing, are developed based on standardized testing methods that have been modified for the testing of conductive concrete mixtures. As …

Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis

All Theses

Copper-based algaecides and herbicides are commonly used to mitigate risks of problematic algae and weeds, however there are concerns regarding copper accumulation from treatments. Modeling and laboratory experiments can be used to predict copper accumulation and measurement in sediments, as well as benthic invertebrate responses following treatments. Modeling was used to estimate copper residual concentrations in sediments from algaecide and herbicide treatments. Reported and measured method detection limits (MDLs; minimum concentration of an analyte of interest that can be measured with 99 percent confidence in a specific matrix using an analytical method) were compared to model estimated copper residual concentrations …

Evaluation Of Rubber Modified Porous Asphalt Mixtures, Kimberly Lyons

All Theses

A porous pavement is a type of sustainable pavement that allows stormwater to infiltrate through the pavement into the natural soil bed. Rubber modified binder is the combination of regular asphalt binder mixed with ground crumb rubber, which is derived from used rubber tires by shredding or grinding the tires into small fragments. This research investigated the effects of rubber modified binder on the performance properties of porous asphalt mixtures, which include draindown, porosity, permeability, abrasion resistance, moisture susceptibility, and rutting resistance.
The addition of cellulose fibers has been used to increase the optimum binder content of porous asphalt mix …

The Effect Of Mortar Strength On The Standard Test For Strand Bond, Cameron Murray

Civil Engineering Undergraduate Honors Theses

The prestressed industry is moving towards adopting the Standard Test for Strand Bond (STSB) to quantify the bond capacity of prestressing strand. In the test, strand is pulled through an 18 in. cylindrical casing filled with mortar. The force corresponding to the dead end displacement of 0.1 in. is recorded and this value is used to quantify strand bond. One of the concerns of the test is the requirement of a mean mortar strength of 4,500 to 5,000 psi during testing. There is concern that this 500 psi range may be too difficult to achieve. A study was conducted to …

3d Reconstruction For Post-Disaster Analysis Of Civil Infrastructure, Joshua Caron

All Theses

Following a natural disaster, there is a need to rapidly assess the safety of civil infrastructure. This job is typically undertaken by local governments with the help of volunteer civil engineers with structural expertise, as well as organizations such as Cal EMA and ASCE. However, the inspection process is labor-intensive and a bit tedious, and results are prone to error as they tend to rely on the individual expertise of the inspectors. 3D reconstruction stands to become a useful tool in the safety evaluation process, as well as providing valuable opportunities for forensic engineering. This research explores the application of …

Investigation Of The Physical And Molecular Properties Of Asphalt Binders Processed With Used Motor Oils, Mohyeldin Ragab, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this work we investigated the performance aspects of addition of used motor oils (UMO) to neat and crumb rubber modified asphalts (CRMA) and related that to the change of molecular size distribution of modified asphalt’s fractions; asphaltenes, saturates, naphthene aromatics, and polar aromatics. Based on the results of temperature sweep viscoelastic tests, addition of crumb rubber modifier (CRM) alone or with UMO results in the formation of internal network within the modified asphalt. Based on the results of short and long term aged asphalts, the utilization of combination of UMO and CRM enhanced the aging behavior of asphalt. Bending …

Laboratory Investigation Of The Effects Of Temperature And Moisture On Interface Shear Strength Of Textured Geomembrane And Geosynthetic Clay Liner, Taki Stavros Chrysovergis

Master's Theses

A laboratory investigation was conducted to determine the effects of temperature and moisture on the shear strength of textured geomembrane (T-GM) and geosynthetic clay liner (GCL) interface. Several landfill slope failures involving geosynthetics have occurred within the past three decades. Interface shear strength of T-GM/GCL is well documented for testing conducted at laboratory temperatures and at moisture contents associated with GCLs in submerged conditions. However, in-service conditions for landfill liner systems include a wide range of temperatures (extending from below 0 °C to above 40 °C) and a wide range of moisture conditions. Large-scale interface direct shear tests were performed …

Effect Of Scc Mixture Composition On Thixotropy And Formwork Pressure, A. F. Omran, Kamal H. Khayat, Y. M. Elaguab

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High lateral pressure exerted on formwork systems by self-consolidating concrete (SCC) is one of the hindrances for using such highly flowable concrete in cast-in-place applications. Self-consolidating concrete is a complex system that can be made using a wide range of mixture proportioning and often incorporated various chemical admixtures and supplementary cementitious materials. the investigation of the effect of each material ingredient independently on lateral pressure of SCC is not a simple task. in this study, thixotropy is rather used to assess the effect of various mixture parameters on formwork pressure. Thixotropy is determined by the evaluation of the structural buildup …

Quantifying The Effect Of Nanoparticles On As(V) Ecotoxicity Exemplified By Nano-Fe2o3 (Magnetic) And Nano-Al2o3, Ji Hu, Demin Wang, Brett E. Forthaus, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Nano-Fe₂O₃ (magnetic) and nano-Al₂O₃ are increasingly used in biomedical fields for cellular labeling and drug delivery, and in the industry as catalysts. However, they may also serve as carriers of toxic contaminants and negatively impact the environment and human health. in the present study, Ceriodaphnia dubia was used to assess the toxicity of these nanoparticles (NPs) with and without the presence of background arsenic(V) (As[V]). the results showed that although these NPs alone did not exhibit significant toxicity in the experimental concentration range, they could significantly enhance the toxicity of As(V). the accumulation of …

Seepage And Stability Of A Dam In An Artesian Setting, Sean A. Parks

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

Willow Creek Dam is located in a unique region on the boundary of a confined aquifer, where artesian conditions exist. Recently, groundwater levels have exceeded the elevation of the downstream berm well above anticipated piezometric elevations. It was presumed from limited evidence that these high piezometric levels resulted from pressure in the aquifer rather than from seepage out of the reservoir. The purpose of this investigation was to determine the relative contributions of the reservoir and the regional groundwater to observed piezometric levels and how these levels affect seepage exit gradients and slope stability of the dam.

Comparing the head …

Urban Trail System Planning In The Western United States: An Analysis Of The Trail-Specific Planning Efforts Of Four Cities That Have Implemented Urban Trail Systems, Kenneth C. Richley

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

States in the Western United States are growing at rates outpacing the rest of the nation. This growth is placing pressure on communities to develop their current open space for residential or commercial use. As cities develop a comprehensive open space plans, several elements arise. One critical element is connectivity. This connectivity is most often realized in the form of greenways. In many cities these greenways contain urban trail systems that provide significant recreation and connectivity benefits.

This thesis investigates the current recommended models used to plan for greenway, synthesizes them into a recommended model process, and analyzes case studies …

An Error Quantification Methodology For Hurricane Storm Surge Simulations, Bin Pei

All Theses

This thesis describes the development of a procedure to quantify errors in hurricane storm surge simulations using a decoupled wind-surge model. The state-of-the-art storm surge simulation program, ADCIRC (Advanced Circulation), and the Georgiou's wind field model were used to simulate the storm surge heights associated with 169 historical hurricanes from 1922 to 2011 along the coast of North Carolina, South Carolina and Georgia. The storm surge modeling errors were quantified by comparing the measured to the simulated annual maximum surge heights at nine water level observation stations maintained by the Center for Operational Oceanographic Products and Services (CO-OPS). The simulated …

Microbiologically Enhanced Mixing Across Scales During In-Situ Bioremediation Of Uranium, Reinaldo E. Alcalde

McNair Scholars Research Journal

Production of nuclear fuels for weapons and electric energy has resulted in groundwater uranium contamination at Department of Energy (DOE) sites. Reduction of uranium by dissimilatory metal-reducing bacteria (DMRB) is an effective approach for in-situ bioremediation of these sites. In this process, an organic electron donor is typically delivered through a well into groundwater in order to promote the biological reduction of soluble and toxic U(VI) to insoluble and less toxic U(IV). A key challenge is mixing the organic electron donor with U(VI) in groundwater where laminar flow conditions prevail. A potential solution is to enhance reaction beyond the scale …

The Implementation Of A Versatile Pseudodynamic Hybrid Simulation For Seismic Evaluation Of Structural Systems, Chelsea Griffith

Masters Theses

Pseudodynamic hybrid simulation technique was developed to evaluate structural seismic performance by physically testing the critical portion with the remaining structure simulated using a numerical model in the computer. An incremental approach was adopted in developing the control scheme to suit multiple testing facilities and test specimens. First the small scale, predictable specimen was utilized to investigate techniques of improving stability, slowing down the loading rate and triggering the accurate force measurement in a series of at benchmark scale experiments in the Laboratory of Earthquake and Structural Simulation at Western Michigan University (WMU). A step/hold command scheme was developed and …

Analysis And Evaluation Of Existing And Novel Turbulent Dynamic Pressure Based Methods For Measuring Bridge Pier And Abutment Scour, Murray Fisher

All Dissertations

Scour is one of the most significant threats to bridge infrastructure and is the leading cause of failure within the United States. Given this risk to the nation’s transportation infrastructure, it is necessary to understand the development of scour holes around bridge piers and abutments. This can be achieved with scour monitoring, a Federal Highway Administration approved scour countermeasure. As the monitoring techniques available range from simple devices that rest on or in the channel bed to advanced scanning systems that provide a bed contour profile, a concise study of the state of the art in real time scour measurement …

Determination Of The Maximum Mgs Mounting Height Phase Ii Detailed Analysis, Ramen D. Julin, Ronald K. Faller, John D. Reid, Mario Mongiardini

Nebraska Department of Transportation: Research Reports

No abstract provided.

Characteristics Of Fatigued Commercial Motor Vehicle Drivers -- A Preliminary Investigation, Aemal Khattak, Carrie Mohlman

Nebraska Department of Transportation: Research Reports

The goal of this research was to identify and correlate easily observable characteristics of drivers to different levels of fatigue, thus enabling state patrol officers to make more judicious decisions related to driver fatigue. A literature review was conducted pertaining to the characteristics of fatigued drivers. Next, a nationwide survey was administered to state patrol agencies to assess their practices regarding fatigue-involved driving. To explore relationships between state patrol agency practices and vehicular safety, data collected from the telephone survey were merged with data from different states on fatigue-involved vehicle fatalities and vehicle miles traveled. Analysis revealed that states with …

Cable Median Barrier Failure Analysis And Prevention, Dean L. Sicking, Cody S. Stolle

Nebraska Department of Transportation: Research Reports

Cross-median crashes have been identified as one of the highest injury or fatality risk crash types. Although crossmedian crashes account for only 2% to 5% of all median crash events, they are disproportionately represented in the number and frequency of fatalities on interstate roadways. Many states have utilized cable median barriers to reduce the risk of cross-median crashes, frequently with great success. However, cable median barriers are also fixed obstacles to errant vehicles. Cable median barriers can place occupants at increased risk of severe injury or fatality if the barrier fails to adequately contain and redirect errant vehicles, resulting in …

Dynamic Testing Of Mgs W6x8.5 Posts At Decreased Embedment, Robert W. Bielenberg, Karla A. Lechtenberg, Ronald K. Faller, John D. Reid, Tyler L. Schmidt, Mario Mongiardini

Nebraska Department of Transportation: Research Reports

No abstract provided.

Evaluation Of The Environmental Impacts Of Bridge Deck Runoff, Shannon L. Bartelt-Hunt, Lauren Swadener, Ekizabeth G. Jones

Nebraska Department of Transportation: Research Reports

Bridges are located in very close proximity to receiving waters, and regulatory agencies often require specific stormwater control measures for bridge deck runoff. While there is some information available on roadway runoff, few studies have focused on bridge deck runoff. Currently, there is no information available regarding the impacts of bridge deck runoff on receiving waters in Nebraska. Due to the cost, maintenance, and design issues associated with implementing structural controls for bridge deck runoff, it is important to develop a better understanding of the relationship between bridge deck runoff and potential impacts to receiving streams. The objectives of this …

Implementation And Validation Of Fault-Rupture Response Spectrum Analysis Procedure In Csibridge For Bridges Crossing Earthquake Fault Ruptures, Jennifer Evelyn Tures

Master's Theses

This thesis evaluates the application of a simplified analysis procedure as implemented in version 16 of CSiBridge^TM for design of bridges crossing earthquake fault ruptures. The fault-rupture response spectrum analysis (FR-RSA) approximation method has been proved adequate for both straight and curved ordinary bridges, but lacked a comfortable interface to accommodate the method users. Computers and Structure, Inc. has implemented the FR-RSA procedure into CSiBridge^TM, a user-friendly integrated 3-D bridge design software, as an added seismic design feature. By combining the response of the bridge due to the quasi-static displacement from the fault strike-slip rupture and the …

Seismic Performance Of Symmetric Steel Moment Frames With Random Reactive Weight Distributions, Conner F.F. Williamson

Master's Theses

When a structure undergoes seismic excitation, the intensities and spatial distributions of the reactive weights on the structure may not be the same as those assumed in original design. Such a difference is inevitable due to many facts with the random nature (e.g., redistribution of live load), resulting in accidental eccentricity and consequently torsional response in the system. The added torsion can cause excessive deformation and premature failure of the lateral force resisting system and its detrimental effect is typically accounted for in most building design codes with an arbitrarily specified accidental eccentricity value. While it tends to amplify drift …

Pervious Pavement Infiltrometer, Madeline Musgrove

BioResource and Agricultural Engineering

This project tests infiltration rates on three different slabs of pervious pavement. A methodology was put in place to ensure that all three slabs were tested the same way. The test that is used for the infiltration rates is a constant head test. A steel ring is placed on the surface of the pervious pavement and sealed with Plumbers Putty around the bottom of the ring. A mark is then sketched on the inside of the ring at 2 inches above the surface of the pavement for a constant backpressure that is equal in all scenarios. Five gallons of water …

In-Plane Shear Resistance Of Sustainable Structural Walls With Large Openings, Matija Radovic

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Shear walls are primary structural systems that support building against lateral loads (tornadoes and hurricanes). Even though concrete shear walls are the most efficient lateral resisting system, they are rarely used in a residential construction. The reasons for why contractors do not use concrete walls in residential construction were due to higher construction cost and slower construction paces. This study proposes building and testing residential concrete structural wall system that is energy efficient, cost competitive and structurally safe.

In order to decrease environmental impact of the residential construction process, this study proposed implementing sustainability concept while building residential structures. The …