Civil and Environmental Engineering Commons^™

Investigating The Interaction Of Ndot Hot-Pour Pcc Joint Sealant And Penetrating Concrete Sealers, Bruce Barrett, Dale Byre, Wally Heyen, Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

Based on the field observations on NE-83, PCS potentially impacts the bond between the concrete and hot-pour sealant after application. If penetrating sealers break the interfacial bond after application, concrete pavements could become compromised and subject to freeze-thaw damage, chloride attack, and other deleterious effects.

The results show that discoloration occurred when applying the five PCS products to the NE-3405 hot-pour sealed testing blocks. All three test methods of application; spraying, 1-min, and 5-min soaks, caused discoloration. The level of discoloration increased with the duration of contact with the PCS. Despite discoloration, none of the five PCS products caused de-bonding …

Research On High-Rap Asphalt Mixtures With Rejuvenators - Phase Ii, Hamzeh Haghshenas, Gabriel Nsengiyumva, Yong-Rak Kim, Kommidi Santosh, Soroosh Amelian

Nebraska Department of Transportation: Research Reports

A previous study by the authors have demonstrated effectiveness of three rejuvenators: R1 (triglyceride/fatty acid: agriculture-tech based), R2 (aromatic extract: petroleum-tech based), and R3 (tall oil: green-tech based) on rejuvenating properties of the aged binder. In that study, it was observed that the rejuvenators made high-RAP mixtures softer and more compliant, which may increase the rutting potential, while they simultaneously improve cracking resistance of the high-RAP materials. Research outcomes and findings from the previous study resulted in consequential research needs for more specific investigation of high-RAP mixtures with rejuvenators in order to achieve realistic implementation into future high-RAP paving projects …

Validation Of The Mechanical Rocker Test Method For Ice Melting Capacity (Mrt-Imc), Lieska Halsey, David Hansen

Nebraska Department of Transportation: Research Reports

The anti-icing and deicing industry has interest in the development of an objective, repeatable test procedure for the evaluation and comparison of anti-icing and deicing products. Pursuant to this goal, the Nebraska Department of Transportation (NDOT) funded research at the University of Nebraska-Lincoln (UNL) to investigate methods for evaluating deicing products, beginning in 2011[1]. Researchers at UNL developed the procedure for the Mechanical Rocker Test for Ice Melting Capacity (MRT or MRT-IMC) in 2014[2].

From 2017-2019, NDOT evaluated the MRT-IMC procedure for validity and suitability as a standard test procedure for assessing deicer performance. NDOT also explored opportunities to improve …

Cpt-Based Pile Design, Chung R. Song, Seunghee Kim, Binyam Bekele, Jingtao Zhang, Alex Silvey

Nebraska Department of Transportation: Research Reports

The geotechnical design of a pile foundation is concerned with the determination of the safe magnitude of an external load that the foundation can carry without jeopardizing the stability of the supported structure. In recent years, in-situ sounding tests are becoming a more attractive method to predict pile capacity due to the rapid development of testing instruments, improved understanding of their mechanics and interpretation, and cost efficiency. The cone penetration test (CPT) and its upgraded version, the piezocone penetration test (PCPT), are the most widely used in situ sounding tests to predict pile capacity. This research report compared eight CPT-based …

Groundwater Transfer And Injection Pilot Project: Construction Of A Three Dimensional Groundwater Flow Model, Wesley Bluvstein

Electronic Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer has experienced substantial groundwater declines in eastern Arkansas and northwest Mississippi due largely to irrigation for rice corn soybeans and other water intensive crops. To alleviate groundwater decline and ensure future sustainability of water resources the U.S. Department of Agriculture has in conjunction with the U.S. Geological Survey and the University of Mississippi initiated studies to determine potential avenues of remediation. Options include improved irrigation efficiency installation of surface weirs inter-basin transfers and groundwater transfer and injection. This study develops a three-dimensional groundwater flow model of a withdrawal well adjacent to a river for …

Fuzzy Multicriteria Decision-Making Model For Time-Cost-Risk Trade-Off Optimization In Construction Projects, M. Ammar Alzarrad, Gary P. Moynihan, Muhammad T. Hatamleh, Siyuan Song

Faculty Publications

As is often the case in project scheduling, when the project duration is shortened to decrease total cost, the total float is lost resulting in added critical or nearly critical activities. This, in turn, results in decreasing the probability of completing the project on time and increases the risk of schedule delays. To solve this problem, this research developed a fuzzy multicriteria decision-making (FMCDM) model. The objective of this model is to help project managers improve their decisions regarding time-cost-risk trade-offs (TCRTO) in construction projects. In this model, an optimization algorithm based on fuzzy logic and analytic hierarchy process (AHP) …

Co 2 -Wettability Of Sandstones Exposed To Traces Of Organic Acids: Implications For Co 2 Geo-Storage, Muhammad Ali, Muhammad Arif, Muhammad Faraz Sahito, Sarmad Al-Anssari, Alireza Keshavarz, Ahmed Barifcani, Linda Stalker, Mohammad Sarmadivaleh, Stefan Iglauer

Research outputs 2014 to 2021

Wettability of CO 2 -brine-mineral systems plays a vital role during geological CO 2 -storage. Residual trapping is lower in deep saline aquifers where the CO 2 is migrating through quartz rich reservoirs but CO 2 accumulation within a three-way structural closure would have a high storage volume due to higher CO 2 saturation in hydrophobic quartz rich reservoir rock. However, such wettability is only poorly understood at realistic subsurface conditions, which are anoxic or reducing. As a consequence of the reducing environment, the geological formations (i.e. deep saline aquifers) contain appreciable concentrations of various organic acids. We thus demonstrate …

Modeling Changes In Public Transit And Private-For-Hire Usage When Implementing A Spatial Tax, Ty Lazarchik

REU Final Reports

Private-for-Hire (PfH) transportation options, such as Uber, Lyft, and taxicabs, are consistently growing in popularity. With this expanded utilization, cities are struggling to maintain usage of their public transit systems. While PfH transportation has been heavily researched, there is a need to further study how its effects on transit usage may be minimized. In this paper, previous work in traffic modeling and analysis of transit and PfH differences are expanded to develop an agent-based decision model in order to simulate and analyze the effectiveness of implementing a location-based tax in and around the city center of Portland, Oregon. The results …

Taylor's Slope Stability Chart For Combined Effects Of Horizontal And Vertical Seismic Coefficients, Pragyan Sahoo, Sanjay Kumar Shukla

Research outputs 2014 to 2021

Design standards and codes of practice on earth slope stability often recommend the pseudo-static method of analysis for determining the factor of safety of a slope subjected to seismic forces. In most pseudo-static methods of analysis, the horizontal seismic force is considered without due weightage to vertical seismic force. In the past, Taylor's stability chart for a homogeneous cohesive-frictional soil slope has been extended to consider the effect of horizontal seismic force only. In this paper, an attempt is made to develop an analytical formulation considering both horizontal and vertical seismic forces in order to estimate the factor of safety …

Finite Element Modeling Of Mechanically Stabilized Earth Walls Built With Welded Wire Wall Panels, Dejuan G. Solan

College of Graduate Studies: Theses & Dissertations

In this thesis, a finite element modeling of Mechanically Stabilized Earth (MSE) walls using welded wire wall panels was performed. The implementation of finite element modeling and analysis proved to be quite efficient in simulating the three-dimensional behavior of wall panels that are a part of MSE walls. The comprehensive finite element model included defined concrete and steel material properties in order to present both the realistic behaviors of each component in the model as well as better facilitating and increasing the accuracy of the simulation of numerous finite element analysis (FEA) cases. FEA was employed to simulate welded wire …

Accuracy Of 3d Point-Cloud And Photo-Based Models Of City Street Intersections, Mariah D. Peart

College of Graduate Studies: Theses & Dissertations

From Georgia Southern University’s Built Environment and Modeling lab, this study compares point positions and distance measurements completed with state-of-the-art instruments and equipment. A modern, 12-second, laser scanner, a modern unmanned aerial vehicle and a highly accurate, 1-second robotic total station were employed for this study. The latter serving as the benchmark instrument. The main objective of this quantitative comparison is to explore the accuracy and usability of a relatively large point-cloud model, as a virtual surveying tool for redesign/reconstruction purposes. This project involves the generation of large, 3D, point-cloud models of two busy and complex city street intersections. One …

Actual Evapotranspiration And Crop Coefficients Of Irrigated Lowland Rice (Oryza Sativa L.) Under Semiarid Climate, Koffi Djaman, Daran R. Rudnick, Yonnelle D. Moukoumbi, Abdoulaye Sow, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Lowland irrigated rice is the predominant crop produced in the Senegal River Valley characterized by very low annual rainfall, high temperatures, and low relative humidity. The Senegal River is shared by Senegal, Mali, Mauritania, and Guinea, and serves as the main source of irrigation water for the adopted double rice cropping system. Developing appropriate resource management strategies might be the key factor for the sustainability of rice production in the region. This study aims to estimate rice seasonal evapotranspiration (ETa), irrigation water requirement, and to develop rice growth stage specific crop coefficients (Kc) to improve rice water productivity. Field experiments …

Metabolic Compounds Within The Porcine Uterine Environment Are Unique To The Type Of Conceptus Present During The Early Stages Of Blastocyst Elongation, Sophie C. Walsh, Jeremy R. Miles, Linxing Yao, Corey D. Broeckling, Lea A. Rempel, Elane C. Wright-Johnson, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The objective of this study was to identify metabolites within the porcine uterine milieu during the early stages of blastocyst elongation. At Days 9, 10, or 11 of gestation, reproductive tracts of White cross‐bred gilts (n = 38) were collected immediately following harvest and flushed with Roswell Park Memorial Institute‐1640 medium. Conceptus morphologies were assessed from each pregnancy and corresponding uterine flushings were assigned to one of five treatment groups based on these morphologies: (a) uniform spherical (n = 8); (b) heterogeneous spherical and ovoid (n = 8); (c) uniform ovoid (n = 8); (d) heterogeneous …

Development Of A Readiness Model For The Application Of Precast Concrete In Housing Construction: A Case Study In Myanmar, Aung Phone Myint

Chulalongkorn University Theses and Dissertations (Chula ETD)

Precast concrete construction has been verified that it is one of the solutions for the growth of urbanization and housing development. In addition, it helps to reduce the labor requirement and material wastage in construction. However, the use of precast concrete technology is not still popular and not widely used within the Myanmar housing construction industry. Moreover, there is no readiness assessment model encompassed the readiness of construction industry including major stakeholders who are representatives of the construction industry for accepting the new technology. Therefore, the aim of this study is to develop a readiness model that can assess the …

Enhancement Of Municipal Wastewater Management System With Polluter Pays Principle (Ppp): A Case Study Of Cities In Thailand, Kwanmanas Meethavorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Poor water quality in public water bodies caused by several reasons mainly due to a lack of efficient WWM system and sufficient financial support. Polluter pays principle has long been a promising strategy to help improving water quality in pubic water bodies in Thailand. However, WW charge has not yet been practically levied. This research ains to evaluate factors affecting residents' preferences on WTPs for water quality improvement. Three different characteristic cities were selected as case studies. The technique applied to estimate WTPs is CVM to reveal key factors influencing WTP decision as well as WTP pay-out level. The result …

A Study On End-Anchorage And Bond Behavior Of Steel-Fiber Reinforced Cementitious Matrix Composites Externally Bonded To A Concrete Substrate, Christopher Michael Moore

Masters Theses

"Fiber reinforced cementitious matrix (FRCM) composites are a strengthening material consisting of continuous fibers embedded in an inorganic matrix that have the potential to provide additional flexural and shear strength to concrete and masonry members. When used for external strengthening, however, debonding of the material is often observed due to slippage of the fiber with respect to the matrix, causing loss of composite action and a reduction in load carrying capacity. The composite utilized in this study consisted of continuous steel fibers embedded in an inorganic cementitious matrix bonded to a concrete prism. Additionally, an end-anchorage system was implemented with …

Evaluation Of Naturally Occurring And Anthropogenic Contamination In Missouri Streams, Christina Jane Sehrt

Masters Theses

"The goal of this study is to observe the values and variability of water quality parameters and benthic macroinvertebrates in watersheds with very little anthropogenic impact and to compare these values with those acquired in watersheds with more anthropogenic impact. The following five HUC 12-digit watersheds had very little anthropogenic impact and were considered "pristine": Rogers Creek, Mill Creek, Middle West Fork-Black River, Bee Fork, and Ottery Creek. Five largely urban sub-basins were also considered; these basins are: Grand Glaize Creek, Glaize Creek, Sugar Creek, Hominy Creek, and Grindstone Creek. For each watershed, both water quality parameters and benthic macroinvertebrates …

Development Of Test Methods For Characterizing Extrudability Of Cement-Based Materials For Use In 3d Printing, Jonathan Thomas Kuchem

Masters Theses

"3D printing is the process of creating three-dimensional objects using an automated additive manufacturing process. The 3D printing process has been used with materials such as metals and polymers, but application with cement based materials for the construction industry has yet to be developed. In this research, two main problems were investigated for printing cement based composite materials: extrudability and tensile reinforcement. Fiber-reinforced concrete (FRC) was studied as an internal reinforcing system to increase tensile/flexural strength. First, FRC was studied to investigate mechanical properties and use of fibers from waste tires as an environmentally friendly option. A reference mixture with …

Abrasion Resistant Concrete Mix Design For Cold Climates, Diane Mariah Murph

Masters Theses

“Studded tire usage in Alaska contributes to rutting damage on pavements resulting in high maintenance costs and safety issues. In this study, binary, ternary, and quaternary highly-abrasion resistant concrete mix designs using supplementary cementitious materials (SCMs) were developed. The properties of fresh concrete and mechanical, and durability properties of hardened concrete for these mix designs were then tested to determine an optimum highly-abrasion resistant concrete mixture which could be placed in cold climates to reduce rutting damage. SCMs used included silica fume, ground granulated blast furnace slag, and type F fly ash. Tests including workability, air content, drying shrinkage, compressive …

Unmanned Aerial And Traversing Vehicle -- A Mobile Platform For Bridge Inspections, Clayton A. Fritsche

Masters Theses

“Unmanned aerial vehicles (UAVs), also known as drones, have been rapidly growing in popularity since their creation. This study aimed to create a robotic platform used to assist in the inspection process of the nation’s aging and deteriorating bridges. To this end, a multimodal inspection robot that utilized both flying and driving technologies, was designed, analyzed, and tested for aerial, traversing, and their transitional operability. The design, herein referred to as the “BridgeBot”, was evaluated both computationally and experimentally. A finite element model of the BridgeBot was established and analyzed under static loading scenarios to help determine stress distributions and …

Performance Of One-Part And Two-Part Class C Fly Ash-Based Alkali Activated Mortars, Cedric Chani Kashosi

Masters Theses

“Seeking an eco-friendly concrete, researchers have conducted studies to fully replace ordinary Portland cement (OPC) with fly ash (FA) producing alkali-activated concrete (AAC). Results showed better performance of AAC in terms of high early compressive strength, and durability compared to conventional concrete. However, much is still unknown about the behavior of AAC. From the type of materials used, the curing procedure, and long-term strength development of these binders; a thorough investigation is needed in order to fill the existing gap from previous studies and thus make a step forward to the safely use of AAC in the construction industry. The …

Feasibility Study For Sustainable Controlled Low-Strength Material (Clsm) Incorporating Off-Specification Fly Ash And Bottom Ash, Alexis K. Vandomelen

Masters Theses

“Controlled low-strength material (CLSM) is a self-consolidating cementitious material used in applications requiring high flowability and low strength. The primary components of this material, being cement and sand, however, negatively impact the environment. Cement is a large contributor to CO2 emissions, and the vast depletion of sand causes physical and political issues. Furthermore, over 100 million short tons of coal combustion products (CCP), including fly ash and bottom ash, are created annually in the United States, while nearly half of all CCP remain unused. No off-specification fly ash has been implemented in CLSM. This study uses coal ashes sourced from …

Determination Of Shrinkage Of Fine-Grained Soils Using 3d Scanning Technology, Hemant R. Joshi

Honors Theses

Shrinkage Limit is the moisture content parameter in fine grained soil which is related to the volume stability of the soil. The conventional method, ASTM Standard D427-04 that uses mercury has been replaced by wax method, ASTM Standard D4943-02 that uses wax and water or MT-92 that uses spray coating. This modification has certainly minimized safety concerns of the laboratory technicians by avoiding the use of the health hazardous substance, mercury (Hg) but it is not really an economic and convenient method. This thesis proposes a 3D scanning method of determining the shrinkage limit of fine grained soils. The 3D …

Short Beam Shear Strength Evaluations Of Gfrp Composites: Correlations Through Accelerated And Natural Aging, William Todd Barker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber Reinforced Polymers (FRP) composites have been materials of interest in replacing or reinforcing steel, wood, and concrete, but lack of understanding of degradation under physical and chemical aging is a main concern. Through many years of research, the understanding of aging or durability of GFRPs has improved. To be able to evaluate aging related degradation rates, an accelerated aging methodology under varying environments is introduced. Accelerated aging is a concept used to age composites in a lab controlled environment under varying pH conditions (2 to 13) and temperatures (~ -20° to +160°F). Once acceleratedly aged testing is completed, Arrhenius …

Computational Modeling And Simulations Of Condition Deterioration To Enhance Asphalt Highway Pavement Design And Asset Management, Zul Fahmi Bin Mohamed Jaafar

Electronic Theses and Dissertations

A nation’s economy and prosperity depend on an efficient and safe transportation network for public mobility and freight transportation. A country’s road network is recognized as one of the largest public infrastructure assets. About 93 percent of 2.6 million miles of paved roads and highways in the United States (U.S.) are surfaced with asphalt. Longitudinal roughness, pavement cracking, potholes, and rutting are the major reasons for rehabilitation of asphalt roads. Billions of dollars are required annually for the maintenance and rehabilitation of road networks. If timely maintenance and rehabilitation are not performed, the pavement damages inflicted by heavy traffic repetitions …

Pathogen And Indicator Organism Inactivation And Quantification For Low-Cost Low-Tech Biosolids Treatment, Karina Eyre

Dissertations, Master's Theses and Master's Reports

Biosolids are a by-product of municipal wastewater treatment which, when treated to reduce pathogens, can be land applied as a fertilizer. Class A biosolids must contain low pathogen levels and are unrestricted in their use. This thesis describes methods to identify pathogen and indicator organism (PIO) inactivation mechanisms and PIO inactivation rates for use in low-cost low-tech Class A processes. Procedures to control the levels of spiked bacteria and viruses, total solids, volatile fatty acids, pH, and temperature in biosolids are described for their use in laboratory experiments. Methods for coliphage in biosolids as a surrogate for total enteric viruses …

The Role Of Ephemeral Stratification, Anoxia, And Entrainment In Mediating Spatiotemporal Trophic State Dynamics In A Lake Michigan Drowned River Mouth System (Mona Lake, Mi), Hayden Henderson

Dissertations, Master's Theses and Master's Reports

Mona Lake, MI (a drowned river mouth system) has become eutrophic as result of cultural eutrophication. The integrated monitoring effort and subsequent modeling (LAKE2K) reported on here has shifted the management focus to internal phosphorus loads (60 percent of annual load, 90 percent of load during the stratified and anoxic period) as a necessary precursor to trophic state change. Sediment phosphorus release can yield extreme elevations (> 1 mgSRP/L) of bottom water soluble reactive phosphorus (SRP), with blooms of potentially toxic cyanobacteria (largely Microcystis) occurring annually. Such blooms are ascribable to stochastic mixing and phosphorus entrainment to the surface waters, …

Design Of A Viability Test For Freshwater Prawn Aquaculture Of Two Different Macrobrachium Species In Aneityum, Vanuatu, Cameron Koizumi

Dissertations, Master's Theses and Master's Reports

There is a unique opportunity for freshwater prawn aquaculture on the island of Aneityum in the Republic of Vanuatu. Aneityum has an abundance of fresh water, the streams and rivers on Aneityum are the natural habitat for a freshwater prawn species, Macrobrachium lar, and the people on Aneityum regularly work on projects using communal labor for the benefit of the community. Aneityum also hosts 40 – 120 cruise ships a year, bringing hundreds of thousands of tourists to Aneityum and the nearby islet Mystery Island which creates a readily available market in which to sell freshwater prawns.

The objective …

Urban Evapotranspiration In Water Scarce Regions Estimates For The Middle Rio Grande Basin, United States And Mexico, Jessica Alger

Dissertations, Master's Theses and Master's Reports

Urban evapotranspiration (ET) in semi-arid and arid regions is an important component of the urban water cycle, especially in regions that have limited freshwater supplies. Understanding urban evapotranspiration in these regions is necessary for assessing and managing water resources and ensuring that conservation strategies are effective and sustainable. The objective of this study is to estimate urban ET in the Middle Rio Grande Basin to provide an understanding of evaporative water losses in semi-arid to arid urban environments for future water management decisions. The focus of this study is on the cities of El Paso, TX, US; Las Cruces, NM, …

Optimizing The Performance Of Complex Engineering Systems Aided By Artificial Neural Networks, Khalil Qatu

Electronic Theses and Dissertations

In the first problem Polyetherimide graphene nanoplatelets papers (PEIGNP) were tested with different graphene loadings varying from 0-97 weight percent (WT%). The resulting stress-strain curves were utilized to develop two ANN models. Stress-controlled and strain-controlled models. Both models shoan excellent correlation to the experimental. Several Mechanical properties were calculated from the predicted stress-strain curves namely; toughness maximum strength maximum strain and maximum tangent modulus. Both models captured the same overall behavior of the PEIGNP composite. However the strain-controlled model was found to predict lower stress than the stress-controlled model. Finally a Graphical User Interface (GUI) was developed to aid in …