Civil and Environmental Engineering Commons^™

Unl-Cc Outdoor Education Center Master Plan, Marie Wagner

Honors Program: Senior Projects (Public)

The following report contains the work done by the group Griswold Engineering in completion of the Senior Design requirements for Civil Engineering and the Honors Requirements of the Project Manager. As the project manager, my job was to organize the project as a whole and to work alongside the Structural Engineer on the project. One of the main problems to overcome was the division of labor amongst the group. The project was originally conceived as a group project with one project manager and five other students to serve as the project engineers in each subdiscipline. Since this group only had …

Development Of A Mash Tl-4 Steel, Side-Mounted, Beam-And-Post, Bridge Rail, Oscar Pena

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

A new steel, side-mounted, beam-and-post, bridge rail was designed, crash-tested, and evaluated according to safety performance guidelines included in the American Association of State Highway and Transportation Officials Manual for Assessing Safety Hardware (MASH) for Test Level 4 (TL-4). The new bridge rail system was designed to be compatible to multiple concrete bridge decks utilized by the States of Illinois and Ohio. Bridge rail configurations were designed and optimized based on weight per foot, constructability, and safety. Post-to-rail and rail-to-rail connections were designed for the new bridge rail. Several concepts for these connections were configured, and after discussion with representatives …

Development Of Post-To-Deck Connections For Use In A Mash Tl-4 Steel-Tube Bridge Rail, Pascual Mauricio

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

A new post-to-deck connection was designed for mounting an upcoming Manual for Assessing Safety Hardware (MASH) Test Level 4 steel-tube bridge rail to the side of the bridge deck to limit impact load transferred to the deck and to minimize the propensity for deck damage during impacts. With preference for the bridge rail system to be compatible for use on all deck configurations, the Illinois and Ohio Departments of Transportation desired the new system to attach to bridge decks comprised of concrete slabs or precasted prestressed, concrete box-beam girders.

A new post-to-deck connection for a new MASH 2016 TL-4 steel-tube …

Electrically Conductive Concrete Mix For Electromagnetic (Em) Ground Plane, Christopher Tuan, Lim Nguyen

Department of Civil and Environmental Engineering: Faculty Publications

Conductive concrete mixtures are described that are configured to reflect, for instance, EM waves propagating from an EM pulser onto the conductive concrete mixture forming a ground plane, rather than absorb or dissipate the electromagnetic energy. The conductive concrete mixtures include cement, aggregate, water, metallic conductive material, and conductive carbon particles.

Civil Engineering Design Of Cornhusker Council's Outdoor Education Center, Kelly Weiler

Honors Program: Senior Projects (Public)

A team of geotechnical, structural, hydraulic, environmental, and transportation experts collaborated to provide engineering solutions to the Cornhusker Council in an effort to solve the current problems facing their Outdoor Education Center. This results of this project provided the structural design of three bridges on the property, transportation plans for two parking lots and roadway design, geotechnical recommendations for soil testing and erosion prevention, and an environmental and hydraulic analysis of the property. A major challenge in the design of this project is the consideration of the dangers and regulations that accompany the floodway and floodplain regions on site. Various …

Wheat Strip Effects On Microbial Transport Following Variable Applications Of Beef Cattle Manure, Lisa M. Durso, John E. Gilley, David B. Marx, Chance A. Thayer, Bryan L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vegetative filter strips (VFS) consisting of perennial vegetation have been successfully used to reduce the transport of contaminants in runoff from land application areas. The effectiveness of a winter wheat strip, which may be more acceptable to producers, in reducing microbial transport was examined in this study. A 1.4 m wheat strip was used to allow direct comparison with experimental results obtained in previous studies. Beef cattle manure was applied to 0.75 m wide by 4.0 m long plots established on an Aksarben silty clay loam located in southeast Nebraska. Manure was added at rates required to meet the 0- …

Using Theoretical And Experimental Particle Packing For Aggregate Gradation Optimization To Reduce Cement Content In Pavement Concrete Mixtures, Miras Mamirov

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

The main objective of this study was to evaluate the effect of aggregate particle packing optimization and cement reduction on Nebraska slip-form pavement concrete performance. A literature review was conducted to examine different aggregate optimization tools, quality control tests, and historical data of Nebraska Department of Transportation (NDOT) mixtures. It was found that the Modified Toufar Model has good potential in optimizing particle packing and predicting packing degrees. The combined void content test was found to be useful to experimentally justify optimized aggregate gradations. Two specific pavement concrete workability tests, i.e., the Box Test and the VKelly Test, were used …

Simulation Of Antimicrobial Resistance Gene Fate In Narrow Grass Hedges, Marzieh Khedmati

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

Vegetative Filter Strips (VFS) are used for controlling the volume of runoff and decreasing the contaminants in runoff before entering the water bodies. Many studies investigated the role of VFS in sediment and nutrient removal, but little is known about their efficiency in the removal of emerging contaminants such as antimicrobial resistance genes (ARGs). VFSMOD was used to simulate the efficiency of VFS in this regard. The objectives of this study were to calibrate the VFSMOD with some experimental data and asses the efficiency of the model in simulating the filter behavior in removing ARGs. The tests were conducted in …

Proportion And Evaluation Of Ultra-High Performance Concrete Using Local Materials, Flavia Ribeiro Furtado De Mendonca

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

Ultra-high performance concrete (UHPC) is a new class of concrete that has superior workability, as well as mechanical and durability properties that far exceed those of conventional concrete. To achieve these properties, a very dense internal structure and the very low water-to-binder ratio (w/b) generally are necessary. While particle packing models are typically used to design UHPC, due to the complexity of the composition interaction and characteristics of UHPC, these models might not necessarily provide the best design, which leads to the need of experimental study to justify UHPC performance. The evaluation of the impact of various design parameters on …

34-Inch Tall Three Beam Transition To Concrete Buttress, Scott Rosenbaugh, Wyatt Fallet, Ronald K. Faller, Robert W. Bielenberg, Jennifer Schmidt

Nebraska Department of Transportation: Research Reports

Roadway resurfacing and overlay projects effectively reduce the height of roadside barriers placed adjacent to the roadway, which can negatively affect their crashworthiness. More recently, bridge rails and concrete barriers have been installed with slightly increased heights to account for future overlays. However, adjacent guardrails and approach transitions have not yet been modified to account for overlays. The objective of this project was to develop an increased-height, approach guardrail transition (AGT) to be crashworthy both before and after roadway overlays of up to 3 in. (76 mm).

A 34-in. (864-mm) tall, thrie beam transition was designed such that the system …

Bridge Deck Delamination Segmentation Based On Aerial Thermography Through Regularized Grayscale Morphological Reconstruction And Gradient Statistics, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Environmental and surface texture-induced temperature variation across the bridge deck is a major source of errors in delamination detection through thermography. This type of external noise poises a significant challenge for conventional quantitative methods such as global thresholding and k-means clustering. An iterative top-down approach is proposed for delamination segmentation based on grayscale morphological reconstruction. A weight-decay function was used to regularize the reconstruction for regional maxima extraction. The mean and coefficient of variation of temperature gradient estimated from delamination boundaries were used for discrimination. The proposed approach was tested on a lab experiment and an in-service bridge deck. The …

Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure, Chongsheng Cheng, Ri Na, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Despite decades of efforts using thermography to detect delamination in concrete decks, challenges still exist in removing environmental noise from thermal images. The performance of conventional temperature-contrast approaches can be significantly limited by environment-induced non-uniform temperature distribution across imaging spaces. Time-series based methodologies were found robust to spatial temperature non-uniformity but requires extended period to collect data. A new empirical image filtering method is introduced in this paper to enhance the delamination detection using blob detection method that originated from computer vison. The proposed method employs a Laplacian of Gaussian filter to achieve multi-scale detection of abnormal thermal patterns by …

Evaluation Of Selected Watershed Characteristics To Identify Best Management Practices To Reduce Nebraskan Nitrate Loads From Nebraska To The Mississippi/Atchafalaya River Basin, Aaron R. Mittelstet, Troy E. Gilmore, Tiffany Messer, Daran Rudnick, Thomas Heatherly

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nebraskan streams contribute excess nitrogen to the Mississippi/Atchafalaya River Basin and Gulf of Mexico, which results in major water-quality impairments. Reducing the amount of nitrogen (N) exported in these streams requires the use of best management practices (BMPs) within the landscape. However, proper BMP utilization has rarely been statistically connected to potential controls of N export within watersheds, particularly precipitation and soil characteristics. In this study, 19 watershed variables were evaluated in five categories (hydrological, physiographic, point sources, land use, and soil properties) to determine the characteristics that influenced variable nitrate nitrogen (NO₃-N) concentrations in 17 Nebraska watersheds …

Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

Green water––rainfall over land that eventually flows back to the atmosphere as evapotranspiration––is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water––groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), …

Quantifying And Correcting For Clay Content Effects On Soil Water Measurement By Reflectometers, Jasreman Singh, Tsz Him Lo, Daran Rudnick, Suat Irmak, Humberto Blanco-Canqui

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The presence of clay particles increases the specific surface area of a soil and can affect the calibration of electromagnetic soil water sensors including reflectometers. To quantify and correct for this effect in two relatively new reflectometers, three TDR315 and three CS655 sensors were installed in each of five soils with clay content ranging from 5 to 49%. As the soils were dried in a temperature controlled room, sensor reported soil volumetric water content (θ_v) according to the factory calibration was compared against reference θ_v determined by weighing the soils. Sensor reported θ_v was similar to …

Aesthetics, Ethics, And Lose-Lose Dilemmas In The Anthropocen, Adam Liska

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Anthropogenic climate change will cause violence to increase globally, and nonlinear increases in sea level could cause a major escalation in global conflict. After 2100, a 22-meter sea-level rise is estimated here to dislocate two billion people from coastal areas. These impending civilization-changing events require us to again reevaluate our prevalent aesthetic preferences for luxury that produce a significant fraction of anthropogenic greenhouse gas emissions. Due to industrial inertia, a central dilemma discussed here is the contradictions between the goals and impacts of aesthetics and ethics. Either we lose our own well-being (a loss of high-emission aesthetics) for the benefit …

Deficit Irrigation Management Of Maize In The High Plains Aquifer Region: A Review, Daran Rudnick, Sibel Irmak, C. West, J.L. Chavez, I. Kisekka, T.H. Marek, J.P. Schneekloth, D. Mitchell Mccallister, V. Sharma, K. Djaman, J. Aguilar, M.E. Schipanski, D.H. Rogers, A. Schlegel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigated agriculture is a major economic contributor of the High Plains Region and it primarily relies on the High Plains Aquifer as a source of water. Over time, areas of the High Plains Aquifer have experienced drawdowns limiting its ability to supply sufficient water to sustain fully irrigated crop production. This among other reasons, including variable climatic factors and differences in state water policy, has resulted in some areas adopting and practicing deficit irrigation management. Considerable research has been conducted across the High Plains Aquifer region to identify locally appropriate deficit irrigation strategies. This review summarizes and discusses research conducted …

Biomaterial Substrate Modifications That Influence Cell-Material Interactions To Prime Cellular Responses To Nonviral Gene Delivery, Amy Mantz, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Gene delivery is the transfer of exogenous genetic material into somatic cells to modify their gene expression, with applications including tissue engineering, regenerative medicine, sensors and diagnostics, and gene therapy. Viral vectors are considered the most effective system to deliver nucleic acids, yet safety concerns and many other disadvantages have resulted in investigations into an alternative option, i.e. nonviral gene delivery. Chemical nonviral gene delivery is typically accomplished by electrostatically complexing cationic lipids or polymers with negatively charged nucleic acids. Unfortunately, nonviral gene delivery suffers from low efficiency due to barriers that impede transfection success, including intracellular processes such as …

Meaningful Learner Information For Mooc Instructors Examined Through A Contextualized Evaluation Framework, Kerrie Douglas, Mitch Zielinski, Hillary Merzdorf, Heidi Diefes-Dux, Peter Bermel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Improving STEM MOOC evaluation requires an understanding of the current state of STEM MOOC evaluation, as perceived by all stakeholders. To this end, we investigated what kinds of information STEM MOOC instructors currently use to evaluate their courses and what kinds of information they feel would be valuable for that purpose. We conducted semi-structured interviews with 14 faculty members from a variety of fields and research institutions who had taught STEM MOOCs on edX, Coursera, or Udacity. Four major themes emerged related to instructors’ desires: (1) to informally assess learners as an instructor might in a traditional classroom, (2) to …

Assessing Landscape Scale Heterogeneity In Irrigation Water Use With Remote Sensing And In Situ Monitoring, T. Foster, I. Z. Goncalves, I. Campos, C. M.U. Neale, N. Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Understanding how irrigation is used across agricultural landscapes is essential to support efforts to grow more food while reducing pressures on limited freshwater resources. However, to date, few studies have analyzed the underlying spatial and temporal variability in farmers’ individual water use decisions at a landscape scale.Wecompare estimates of irrigation water requirements derived using state-of-the-art remote sensing models with metered abstraction records for 1400 fields over a 13 year period in the US state of Nebraska, one of the world’s most intensively irrigated agricultural regions. Weshow that farmers’ observed water use decisions often diverge significantly from biophysical estimates of crop …

Optimizing In-Place Density Of Asphalt Pavements During Cold Weather Paving In Nebraska, Robert C. Rea, Hamzeh Haghshenas

Nebraska Department of Transportation: Research Reports

Late season paving is common and often performed in colder temperatures, which is the most challenging environment for attaining optimal in-place density/compaction The in-place density of asphalt pavement greatly affects the lifespan of the pavement. It is also a key factor in preventing major pavement distresses, such as rutting, cracking, stripping (due to water damage) and aging. This research project aims to evaluate and compare the effectiveness of different compaction, delivery, and mix design characteristics to ensure the optimization of in-place asphalt pavement density. To this end, various laydown methods (i.e., Standard Pick-up Machine (SPM) and Material Transfer Vehicle (MTV)) …

Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

In the race to enhance agricultural productivity, irrigation will become more dependent on poorly characterized and virtually unmonitored sources of water. Increased use of irrigation water has led to impaired water and soil quality in many areas. Historically, soil salinization and reduced crop productivity have been the primary focus of irrigation water quality. Recently, there is increasing evidence for the occurrence of geogenic contaminants in water. The appearance of trace elements and an increase in the use of wastewater has highlighted the vulnerability and complexities of the composition of irrigation water and its role in ensuring proper crop growth, and …

Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands

Daugherty Water for Food Global Institute: Faculty Publications

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused …

Impact Of The Application Of Domestic Wastewater By Subsurface Drip Irrigation On The Soil Solution In Sugarcane Cultivation, Aline Azevedo Nazário, Ivo Zution Gonçalves, Eduardo Augusto Agnellos Barbosa, Leonardo Nazário Silva Dos Santos, Daniel Rodrigues Cavalcante Feitosa, Edson Eiji Matsura

Daugherty Water for Food Global Institute: Faculty Publications

The agricultural use of domestic sewage is a viable alternative for recycling nutrients; however, there is concern regarding the impact of its use due to the concentration of chemical elements present in this type of effluent. The use of principal component analysis determines the existence or lack of anomalous samples and the relations between measured variables and their relative contribution among samples that help in monitoring the impact of the use of effluents on soil chemical components. Thus, the objective of this work was to identify nutrient ions present in the soil solution during the first ratoon sugarcane irrigated with …

Public Attitudes About Private Forest Management And Government Involvement In The Southeastern United States, Melissa M. Kreye, Renata Rimsaite, Damian C. Adams

Daugherty Water for Food Global Institute: Faculty Publications

In the southern United States the country’s top wood-producing region, factors such as intergenerational land transfer and population spillover from urban areas have resulted in forestland conversion and reduced production of critical ecosystem services associated with forest systems (e.g., timber, clean water supply, wildlife habitat). Public attitudes, which drive forestland policy prescriptions, may also be evolving due to the way people experience and perceive forests (e.g., recreation), and think about the role of government in private forest decisions. These changes have significant implications for forestland management and the forest-based economy, both locally and globally. We present the results of a …

Mapping Regional Turbulent Heat Fluxes Via Assimilation Of Modis Land Surface Temperature Data Into An Ensemble Kalman Smoother Framework, Xinlei He, Tongren Xu, Sayed M. Bateni, Christopher M. U. Neale, Shaomin Liu, Thomas Auligne, Kaicun Wang, Shoudong Zhu

Daugherty Water for Food Global Institute: Faculty Publications

Estimation of turbulent heat fluxes via variational data assimilation (VDA) approaches has been the subject of several studies. The VDA approaches need an adjoint model that is difficult to derive. In this study, remotely sensed land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) are assimilated into the heat diffusion equation within an ensemble Kalman smoother (EnKS) approach to estimate turbulent heat fluxes. The EnKS approach is tested in the Heihe River Basin (HRB) in northwest China. The results show that the EnKS approach can estimate turbulent heat fluxes by assimilating low temporal resolution LST data from …

Agricultural Water Transfers In The Western United States, Richael Young, Nicholas Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Irrigation for agricultural production represents the largest consumptive use of water in the western United States. Understanding the ways in which agricultural producers respond to physical and institutional water scarcity is therefore key to managing water risk. One of the important risk management tools available to agricultural producers is the ability to transfer water across space and time. Water transfers range from very informal handshake agreements between neighbors to very formal transfers of real property across large distances with mandatory state and federal reporting. Given the range of potential water transfer mechanisms, there are significant knowledge gaps on the variety, …

2019 Nebraska Water Productivity Report, Mesfin Mekonnen, Christopher Michael Usher Neale, Chittaranjan Ray, Galen E. Erickson, Adam Liska, Haishun Yang, Thiago L. Romanelli, Arjen Y. Hoekstra

Daugherty Water for Food Global Institute: Faculty Publications

Nebraska’s agricultural production is diverse and vast, ranking the state fourth in total value of agricultural products in the U.S. The state is a national leader in terms of agricultural production: it is the third largest producer of corn and second largest in cattle production. Nebraska is also the second largest producer of ethanol and distillers’ grains. The production and use of these three commodities are highly interlinked. Corn is a major input in livestock feed and the ethanol industry. Ethanol plants then produce distillers’ grains as a co-product that is also used as livestock feed, thus forming what the …

Grain Yield, Crop And Basal Evapotranspiration, Production Functions And Water Productivity Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, Population Densities And Environments: Part Ii. In South-Central And Northeast Nebraska's Transition Zone And Sub-Humid Environments, Suat Irmak, Ali T. Mohammed, William Kranz

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Information and data on newer drought-tolerant maize hybrid response to water in different climates are extremely scarce. This research quantified the performance of non-drought-tolerant (NDT) (H1) and drought-tolerant (DT) (H2, H3, and H4) maize (Zea mays L.) hybrids response to grain yield, crop evapotranspiration (ETc), basal evapotranspiration (ETb), ETc-yield production functions (ETYPF), and crop water use efficiency (CWUE) at three irrigation levels and two plant population densities (PPDs) at two locations (transition zone between sub-humid and semiarid climates at Clay Center (SCAL), Nebraska, in 2010 and 2012; and in a sub-humid climate at Concord (HAL), Nebraska, in 2010, 2011, and …

Exploring Engineering Club, Samantha Corey, Stephen Yaghmour

Honors Program: Expanded Learning Clubs

Exploring Engineering Club provides an introduction to a variety of engineering problems and piques the students’ interest in engineering by accompanying the information with hands-on problem solving activities mainly related to structural engineering. The activities will often be done in teams which will teach good teamwork skills, as well as problem solving and critical thinking.