Civil and Environmental Engineering Commons^™

Ultra-High Performance Concrete (Uhpc) Deck-To-Girder Connection For Accelerated Bridge Construction, Mostafa Abo El-Khier

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

Precast concrete deck systems have been successfully used for Accelerated Bridge Construction. In most systems, special deck-to-girder connections are designed to achieve structurally composite sections. These connections require tight production/erection tolerances that complicate deck and girder fabrication and compromise the economics of these systems. This study presents a new precast concrete deck-to-girder connection that takes advantage of the excellent mechanical, workability, and durability properties of ultra-high performance concrete (UHPC) to simplify precast concrete deck and girder fabrication and erection. Typical girder shear reinforcement is terminated below the soffit of deck panels to eliminate any conflicts with deck reinforcement and relax …

Impact Of Particle Surface Charge Heterogeneity On Deposition Onto Flat Surfaces And Transport In Porous Media, Thompson Delon

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

Biological and non-biological natural colloids are anisotropic and ubiquitously exist in groundwater. Previously in colloid transport modelling, colloids are assumed to be homogenous for simplification, whether in shape or surface charge. More research has been done to incorporate surface heterogeneity in the transport experiment, i.e., surface charge heterogeneity on collector in column experiment. However, few studies have been done on surface heterogeneity on colloids themselves.

In this dissertation, Janus particles with different surface charge was developed to model surface heterogeneity on colloids. The interaction energy between Janus particle and flat surfaces was analyzed through DLVO simulation. It was discovered that …

Utilizing Digital Image Processing And Two‑Source Energy Balance Model For The Estimation Of Evapotranspiration Of Dry Edible Beans In Western Nebraska, Wei‑Zhen Liang, Isabella Possignolo, Xin Qiao, Kendall Dejonge, Suat Irkmak, Derek M. Heeren, Daran Rudnick

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Having an accurate yet simple method to estimate crop evapotranspiration ( ET_C) is a vital component of reliable irrigation scheduling. In this study, two versions of the two-source energy balance (TSEB) model: the TSEB model with the Priestley–Taylor equation (TSEB-PT) and the Penman–Monteith equation (TSEB-PM), were used to estimate ET_C of dry edible beans in western Nebraska. Compared with previous studies, this study is unique in that a Visual Basic software—Crop Canopy Image Analyzer (CCIA) was developed to process digitally captured RGB canopy images to obtain necessary canopy cover (CC) parameters for the TSEB models such as …

Comparative Study Of Human Pluripotent Stem Cell-Derived Endothelial Cells In Hydrogel-Based Culture Systems, Zhanqi Wang, Fuxing Zuo, Qing Liu, Xuesheng Wu, Qian Du, Yuguo Lei, Zhangmin Wu, Haishuang Lin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Human pluripotent stem cell (hPSC)-derived endothelial cells (ECs) are promising cell sources for drug discovery, tissue engineering, and studying or treating vascular diseases. However, hPSC-ECs derived from different culture methods display different phenotypes. Herein, we made a detailed comparative study of hPSC-ECs from three different culture systems (e.g., 2D, 3D PNIPAAm-PEG hydrogel, and 3D alginate hydrogel cultures) based on our previous reports. We expanded hPSCs and differentiated them into ECs in three culture systems. Both 3D hydrogel systems could mimic an in vivo physiologically relevant microenvironment to protect cells from shear force and prevent cell agglomeration, leading to a high …

Low-Cost Modal Identification Sensors For Bridge Field Testing, Daniel Linzell, Saaed Eftekhar Azam, Samira Ardani, Ahmed E Rageh

Nebraska Department of Transportation: Research Reports

This report provides a framework for experimental load rating of bridges via inclusion of low-cost dynamic sensors and dynamic tests. Currently 25% of the bridges in Nebraska are posted for live load. According to the National Bridge Inventory (NBI) in 2012, 93% of all postings in the US were based analytical load ratings, 7% were posted using field evaluation and engineering judgement, and 1% were posted using experimental load rating methods.

Instrumentation costs and traffic interruptions can be problematic when load testing is necessary to accurately assess in-situ bridge live load capacity. Recent advances in (i) sensing technology and (ii) …

Determination Of Vadose Zone And Saturated Zone Nitrate Lag Times Using Long-Term Groundwater Monitoring Data And Statistical Machine Learning, Martin J. Wells, Troy E. Gilmore, Natalie Nelson, John K. Bohlke

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In this study, we explored the use of statistical machine learning and long-term groundwater nitrate monitoring data to estimate vadose zone and saturated zone lag times in an irrigated alluvial agricultural setting. Unlike most previous statistical machine learning studies that sought to predict groundwater nitrate concentrations within aquifers, the focus of this study was to leverage available groundwater nitrate concentrations and other environmental variables to determine mean regional vertical velocities (transport rates) of water and solutes in the vadose zone and saturated zone (3.50 and 3.75 m yr−1 , respectively). The statistical machine learning results are consistent with two primary …

Role Of Nadþ In Regulating Cellular And Metabolic Signaling Pathways, Sara Amjad, Sabah Nisar, Ajaz A. Bhat, Ab Rauf Shah, Michael P. Frenneaux, Khalid Fakhro, Mohammad Haris, Ravinder Reddy, Zoltan Patay, Joseph Baur, Puneet Bagga

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background: Nicotinamide adenine dinucleotide (NAD⁺), a critical coenzyme present in every living cell, is involved in a myriad of metabolic processes associated with cellular bioenergetics. For this reason, NAD⁺ is often studied in the context of aging, cancer, and neurodegenerative and metabolic disorders.

Scope of review: Cellular NAD⁺ depletion is associated with compromised adaptive cellular stress responses, impaired neuronal plasticity, impaired DNA repair, and cellular senescence. Increasing evidence has shown the efficacy of boosting NAD⁺ levels using NAD⁺ precursors in various diseases. This review provides a comprehensive understanding into the role of NAD^{+ …}

Historical Contingency In Microbial Resilience To Hydrologic Perturbations, Hyun-Seob Song, James C. Stegen, Emily B. Graham, Timothy D. Scheibe

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Development of reliable biogeochemical models requires a mechanistic consideration of microbial interactions with hydrology. Microbial response to and its recovery after hydrologic perturbations (i.e., resilience) is a critical component to understand in this regard, but generally difficult to predict because the impacts of future events can be dependent on the history of perturbations (i.e., historical contingency). Fundamental issues underlying this phenomenon include how microbial resilience to hydrologic perturbations is influenced by historical contingency and how their relationships vary depending on the characteristics of microbial functions. To answer these questions, we considered a simple microbial community composed of two species that …

Modeling The Release And Spreading Of Permanganate From Aerated Slow-Release Oxidants In A Laboratory Flow Tank, Ann Kambhu, Yusong Li, Troy E. Gilmore, Steve D. Comfort

School of Natural Resources: Faculty Publications

Aerated, slow-release oxidants are a relatively new technology for treating contaminated aquifers. A critical need for advancing this technology is developing a reliable method for predicting the radius of influence (ROI) around each drive point. In this work, we report a series of laboratory flow tank experiments and numerical modeling efforts designed to predict the release and spreading of permanganate from aerated oxidant candles (oxidant-wax composites). To mimic the design of the oxidant delivery system used in the field, a double screen was used in a series of flow tank experiments where the oxidant was placed inside the inner screen …

Truck Platooning Effects On Girder Bridges, Joshua Steelman, Jay A. Puckett, Daniel Linzell, Bowen Yang

Nebraska Department of Transportation: Research Reports

Truck platooning – digitally linking two or more trucks to travel in a closely spaced convoy – is increasingly used to save fuel, and reduce driver work and road congestion. Currently, the platoon load effects with several constant headways on bridges have been evaluated and compared to AASHTO design and legal loads. However, reliability assessment and a more rigorous investigation of headway spacing assumptions for truck platoons are lacking. This research provides a framework for determining how much a platoon permit load might be increased given strict control over the load characteristics and operational tactics. The present research evaluates the …

Moving Beyond ‘More Crop Per Drop’: Insights From Two Decades Of Research On Agricultural Water Productivity, Meredith Giordano, Susanne M. Scheierling, David O. Tréguer, Hugh Turral, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Concern over increasing water scarcity has led to the introduction of the concept of agricultural water productivity and an emphasis on interventions to achieve ‘more crop per drop’. Yet, a strong debate continues on how the concept is to be defined and used. Drawing largely from the irrigation literature, the origins of the concept and its methodological developments are reviewed, and its use in applied work over two decades is discussed. Based on this analysis of conceptual and applied research, key insights into the concept’s contributions and limitations are presented, as well as opportunities for further refinements.

Nebraska Water Center Annual Report 2019-2020

Nebraska Water Center: Administrative Materials

Contents

Introduction: Foreword • Director’s Letter • Nebraska Water Center (NWC) Overview and Timeline • In Memoriam: Kyle Hoagland

Research • Water Sciences Laboratory • Nebraska Vadose Zone Program • Ogallala Water Coordinated Agriculture Project • Water for Agriculture Project • Greeley Award • U.S. Geological Survey 104b Projects

Extension & Outreach: NWC Events • Nebraska Nitrate Initiative • Bazile Groundwater Management Area • Water and Integrated Crops Hub • Water Faculty Directory • State Legislative Funding • Water Resources Advisory Panel

Teaching: Know Your Well • Sorab Panday Spotlight • NWC Postdoc Profiles • NWC Student Intern Profiles • …

Identifying Origin-Destination Trips From Gps Data – Application In Travel Time Reliability Of Dedicated Trucks, Li Zhao, Ying Li

Mid-America Transportation Center: Final Reports and Technical Briefs

The advancement of data collection technologies has brought an upsurge in GPS applications. For example, travel behaviour research has benefited from the integration of multiple sources of Global Positioning System (GPS) data. However, the effective use of such data is still impeded by the challenge in data processing. For instance, GPS data, despite providing detailed spatial movement information, do not label the starting and finishing points of a trip, especially for commercial trucks. Hence, there is a critical need to develop a trip identification method to effectively use the trajectory data provided by GPS without additional information. This paper focused …

Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Currently little is known of newer pesticide classes and their occurrence and persistence in recreational lakes. Therefore, the objectives of this study were to (1) assess average pesticide concentrations and loadings entering recreational lakes in three mixed land use watersheds throughout the growing season, (2) evaluate pesticide persistence longitudinally within the lakes, and (3) perform an ecotoxicity assessment. Six sampling campaigns were conducted at three lakes from April through October 2018 to measure the occurrence and persistence during pre, middle, and post growing season. Polar organic chemical integrative samplers (POCIS) were placed in streams near lake inlets and monthly samples …

Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Dissolved arsenic typically results from chemical weathering of arsenic rich sediments and is most often found in oxidized forms in surface water. The mobility of arsenic is controlled by its valence state and also by its association with iron oxides minerals, the forms of which are both influenced by abiotic and biotic processes in aqueous environment. In this study, speciation methods were used to measure and confirm the presence of reduced arsenic species in the surface water of Frenchman creek, a gaining stream that crosses the Colorado- Nebraska border. Selective extraction analysis of aquifer and stream bed sediments shows that …

Evolution Of Three Streambanks Before And After Stabilization And Record Flooding, Matthew Russell, Aaron R. Mittelstet, Tiffany Messer, Jesse T. Korus, R.M. Joeckel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Stabilization projects are increasingly used to mitigate the effects of anthropogenic streambank erosion, yet the effectiveness of stabilization has been insufficiently measured. Sound monitoring practices inform adjustments in implementation and maintenance, which improve engineered effectiveness. Thus, the objectives of this study were to: 1) measure streambank migration from in three reaches stabilized with wooden jetties following a major flooding event, and 2) quantify deposition around the jetties between pre-flood and post-flood. Streambank deposition was measured in 2019 with a River Surveyor and Global Positioning System (GPS). Bank erosion rates in Reaches 1, 2 and 3 were 0.41, 0.96 and 0.07 …

Quantification Of Nitric Oxide Concentration Using Single-Walled Carbon Nanotube Sensors, Jakob Meier, Joseph Stapleton, Eric M. Hofferber, Abigail Haworth, Stephen D. Kachman, Nicole M. Iverson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nitric oxide (NO), a free radical present in biological systems, can have many detrimental effects on the body, from inflammation to cancer. Due to NO’s short half-life, detection and quan- tification is difficult. The inability to quantify NO has hindered researchers’ understanding of its impact in healthy and diseased conditions. Single-walled carbon nanotubes (SWNTs), when wrapped in a specific single-stranded DNA chain, becomes selective to NO, creating a fluorescence sensor. Unfortunately, the correlation between NO concentration and the SWNT’s fluorescence intensity has been difficult to determine due to an inability to immobilize the sensor without altering its properties. Through the …

Arterial Roadway Travel Time Reliability And The Covid-19 Pandemic, Laurence Rilett, Ernest Tufuor, Sean Murphy

Department of Civil and Environmental Engineering: Faculty Publications

This paper evaluated the effect of the COVID-19 preventive orders on arterial roadway travel time reliability (TTR). A comparative analysis was conducted to examine average travel time distributions (TTD), and their associated TTR metrics, before and during the COVID-19 pandemic. Travel time data for four urban arterial corridors in Nebraska, disaggregated by peak period and direction, were analyzed. It was found that in 2020, the average TTD mean and standard deviation values for all 16 scenarios were reduced by an average of 14.0% and 43.4%, respectively. The travel time index, the planning time index, the level of travel time reliability …

New Travel Time Reliability Methodology For Urban Arterial Corridors, Ernest Tufuor, Laurence Rilett

Department of Civil and Environmental Engineering: Faculty Publications

The need for reliable performance measures of urban arterial corridors is increasing because of the rise in traffic congestion and the high value of users’ travel time. Consequently, travel time reliability (TTR), which attempts to capture the day-to-day variability in travel times, has recently received considerable research interest. The basis of all TTR metrics is the underlying travel time distribution (TTD) along the given link or corridor. Estimating and forecasting arterial corridor TTDs for TTR analysis is the focus of this paper. This paper proposes a TTR methodology that addresses some of the limitations of the current U.S. state-of-the-art methodology …

Improving Operational Short- To Medium-Range (Sr2mr) Streamflow Forecasts In The Upper Zambezi Basin And Its Sub-Basins Using Variational Ensemble Forecasting, Rodrigo Valdés-Pineda, Juan B. Valdés, Sungwook Wi, Aleix Serrat-Capdevila, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

The combination of Hydrological Models and high-resolution Satellite Precipitation Products (SPPs) or regional Climatological Models (RCMs), has provided the means to establish baselines for the quantification, propagation, and reduction in hydrological uncertainty when generating streamflow forecasts. This study aimed to improve operational real-time streamflow forecasts for the Upper Zambezi River Basin (UZRB), in Africa, utilizing the novel Variational Ensemble Forecasting (VEF) approach. In this regard, we describe and discuss the main steps required to implement, calibrate, and validate an operational hydrologic forecasting system (HFS) using VEF and Hydrologic Processing Strategies (HPS). The operational HFS was constructed to monitor daily streamflow …

Modeling And Prioritizing Interventions Using Pollution Hotspots For Reducing Nutrients, Atrazine And E. Coli Concentrations In A Watershed, Olufemi P. Abimbola, Aaron R. Mittelstet, Tiffany Messer, Elaine Berry, Anna Van Griensven

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Excess nutrients and herbicides remain two major causes of waterbody impairment globally. In an attempt to better understand pollutant sources in the Big Sandy Creek Watershed (BSCW) and the prospects for successful remediation, a program was initiated to assist agricultural producers with the implementation of best management practices (BMPs). The objectives were to (1) simulate BMPs within hotspots to determine reductions in pollutant loads and (2) to determine if water-quality standards are met at the watershed outlet. Regression-based load estimator (LOADEST) was used for determining sediment, nutrient and atrazine loads, while artificial neural networks (ANN) were used for determining E. …

Assessing Different Plant-Centric Water Stress Metrics For Irrigation Efficacy Using Soil-Plant-Atmosphere-Continuum Simulation, Jingwen Zhang, Kaiyu Guan, Bin Peng, Ming Pan, Wang Zhou, Robert F. Grant, Trenton E. Franz, Daran Rudnick, Derek M. Heeren, Andrew Suyker, Yi Yang, Genghong Wu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Understanding plant water stress (PWS) in the soil-plant-atmosphere-continuum (SPAC) that connects water supply from soil, water demand from atmosphere, and plant self-regulation is a prerequisite for efficient irrigation in response to water scarcity. Currently, PWS can be defined in various ways, for example, based on environmental factors and/or plant-centric metrics. The environment-based metrics usually do not take plants into consideration. Regarding the existing plant-centric metrics, their interconnections and abilities to capture the physical water constraints from both soil water supply and atmospheric water demand are still unclear. This research investigates the theoretical foundations behind different PWS metrics, and assesses their …

Antibiotic Resistance Genes In Swine Manure Slurry As Affected By Pit Additives And Facility Disinfectants, Maria C. Hall, Jon Duerschner, John E. Gilley, Amy Schmidt, Shannon Bartelt-Hunt, Daniel D. Snow, Kent M. Eskridge, Xu Li

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Manure storage facilities are critical control points to reduce antibiotic resistance genes (ARGs) in swine manure slurry before the slurry is land applied. However, little is known about how exogenous chemicals entering the manure storage facilities may affect the fate of ARGs. The objective of this study was to analyze the impact of six commonly used pit additives and four facility disinfectants on the concentration of ARGs in swine manure slurry. Bench scale reactors, each containing approximately 50 L of liquid swine manure, were dosed with additives or disinfectants and were sampled for 40 days. Seven antibiotic resistance genes along …

Differential Survival Of Non-O157 Shiga Toxigenic Escherichia Coli In Simulated Cattle Feedlot Runoff, Lisa M. Durso, John E. Gilley, Daniel N. Miller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Environmental survival time is important when evaluating adverse health outcomes from foodborne pathogens. Although outbreaks associated with manure-impacted irrigation or runoff water are relatively infrequent, their broad scope, regulatory importance, and severe health outcomes highlight the need to better understand the environmental survival of manure-borne pathogens. Shiga toxigenic Escherichia coli (STEC) are excreted in feces and persist in the environment until they die or recolonize a new host. Surface waters contaminated with manure-borne STEC can infect humans through drinking and recreational water use or irrigated crops that are minimally cooked. In this study, manure-impacted water microcosms mimicking beef cattle feedlot …

Editorial: Predictive Modeling Of Human Microbiota And Their Role In Health And Disease, Hyun-Seob Song, Stephen R. Lindemann, Dong-Yup Lee

Department of Agricultural and Biological Systems Engineering: Faculty Publications

No abstract provided.

The Nanotheranostic Researcher’S Guide For Use Of Animal Models Of Traumatic Brain Injury, Brandon Z. Mcdonald, Connor C. Gee, Forrest M. Kievit

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Traumatic brain injury (TBI) is currently the leading cause of injury-related morbidity and mortality worldwide, with an estimated global cost of USD 400 billion annually. Both clinical and preclinical behavioral outcomes associated with TBI are heterogeneous in nature and influenced by the mechanism and frequency of injury. Previous literature has investigated this relationship through the development of animal models and behavioral tasks. However, recent advancements in these methods may provide insight into the translation of therapeutics into a clinical setting. In this review, we characterize various animal models and behavioral tasks to provide guidelines for evaluating the therapeutic efficacy of …

Frontier: Discipline-Based Education Research To Advance Authentic Learning In Agricultural And Biological Engineering, Heidi A. Diefes-Dux

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Discipline-based education research (DBER) is research activity aimed at investigating “learning and teaching in a discipline from a perspective that reflects the discipline’s priorities, worldview, knowledge, and practices” for the purpose of producing research-based evidence to improve education in that discipline. DBER arose out of concerns about the quality of post-secondary science education. Physics, chemistry, engineering, biology, geosciences, and astronomy education each have unique DBER histories in the U.S. that date back to the late 1800s or early 1900s when colleges and university systems were expanding and formalizing. The DBER fields accelerated in the 1950s and 1960s as a result …

In Situ Characterization Of Municipal Solid Waste Using Membrane Interface Probe (Mip) And Hydraulic Profiling Tool (Hpt) In An Active And Closed Landfill, M. Sina Mousavi, Yuan Feng, Josh Mccann, Jongwan Eun

Department of Civil and Environmental Engineering: Faculty Publications

Municipal solid waste (MSW) landfills near a metropolitan area are renewable energy resources to produce heat and methane that can generate electricity. However, it is difficult to use those sources productively because disposed MSW in landfills are spatially and temporally heterogeneous. Regarding the prediction of the sources, the analysis of in situ MSW properties is an alternative way to reduce the uncertainty and to understand complex processes undergoing in the landfill effectively. A hydraulic profiling tool (HPT) and membrane interface probe (MIP) test measures the continuous profile of MSW properties with depth, including hydraulic pressure, temperature, electrical conductivity (EC), and …

A Hybrid Biological-Adsorption Approach For The Treatment Of Contaminated Groundwater Using Immobilized Nanoclay-Algae Mixtures, Sara Mollamohammada, Ashraf Aly Hassan, Mohamed Dahab, Sandeep Kumar

Department of Civil and Environmental Engineering: Faculty Publications

Mixing the Scenedesmus species with nanoclay and immobilizing in sodium was evaluated as a sustainable treatment method for removing nitrate, atrazine, and metals from groundwater. Gel beads containing the hybrid mixture removed 100% of 10 mg/L N nitrate and 98% of 100 μg/L atrazine from synthetic groundwater in three days. The optimal amount of nanoclay was found to be 0.30 mg per bead. The experimental data fit well into a Freundlich adsorption iso- therm and followed pseudo first-order kinetics. When tested in actual groundwater, 91% of nitrate and 100% of Cr, Se, and V were eliminated in three days without …

Identification Of Contributing Factors For Driver’S Perceptual Bias Of Aggressive Driving In China, Yongfeng Ma, Xin Gu, Ya'nan Yu, Aemal Khattak, Shuyan Chen, Kun Tang

Department of Civil and Environmental Engineering: Faculty Publications

Aggressive driving is common across the world. While most aggressive driving is conscious, some aggressive driving behavior may be unconscious on part of motor vehicle drivers. Perceptual bias of aggressive driving behavior is one of the main causes of traffic accidents. This paper focuses on identifying impact factors related to aggressive driving perceptual bias. Questionnaire data from 690 drivers, collected from a drivers’ retraining course administered by the Traffic Management Bureau in Nanjing, China, were used to collect drivers’ socioeconomic characteristics, personality traits, and external environment data. Actual penalty points were considered as an objective indicator and Gaussian mixture model …