Civil and Environmental Engineering Commons^™

Soil Water Extraction Patterns And Crop, Irrigation, And Evapotranspiration Water Use Efficiency Of Maize Under Full And Limited Irrigation And Rainfed Settings, Koffi Djaman, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The effects of full and limited irrigation and rainfed maize production practices on soil water extraction and water use efficiencies were investigated in 2009 and 2010 under center-pivot irrigation near Clay Center, Nebraska. Four irrigation regimes (fully irrigated treatment (FIT), 75% FIT, 60% FIT, and 50% FIT) and a rainfed treatment were implemented. The crop water use efficiency (CWUE, or crop water productivity), irrigation water use efficiency (IWUE), and evapotranspiration water use efficiency (ETWUE) were used to evaluate the water productivity performance of each

treatment. The seasonal rainfall amounts in 2009 and 2010, respectively, were 426 mm (18% below normal) …

Large-Scale On-Farm Implementation Of Soil Moisture-Based Irrigation Management Strategies For Increasing Maize Water Productivity, Suat Irmak, Michael J. Burgert, Haishun Yang, Kenneth G. Cassman, Daniel T. Walters, William R. Rathje, Jose O. Payero, Patricio Grassini, Mark S. Kuzila, Kelly J. Brunkhorst, Dean E. Eisenhauer, William L. Kranz, Brandy Vandewalle, Jennifer M. Rees, Gary L. Zoubek, Charles A. Shapiro, Gregory J. Teichmeier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigated maize is produced on about 3.5 Mha in the U.S. Great Plains and western Corn Belt. Most irrigation water comes from groundwater. Persistent drought and increased competition for water resources threaten long-term viability of groundwater resources, which motivated our research to develop strategies to increase water productivity without noticeable reduction in maize yield. Results from previous research at the University of Nebraska-Lincoln (UNL) experiment stations in 2005 and 2006 found that it was possible to substantially reduce irrigation amounts and increase irrigation water use efficiency (IWUE) and crop water use efficiency (CWUE) (or crop water productivity) with little or …

Evaporative Losses From A Common Reed-Dominated Peachleaf Willow And Cottonwood Riparian Plant Community, Isa Kabenge, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Our study is one of the first to integrate and apply within-canopy radiation physics parameters and scaling-up leaf-level stomatal resistace (r_L) to canopy resistance (r_c) approach to quantify hourly transpiration (TRP) rates of individual riparian plant species—common reed (Phragmites australis), peachleaf willow (Salix amygdaloides), and cottonwood (Populus deltoides)— in a mixed riparian plant community in the Platte River Basin in central Nebraska. Two experimental years (2009 and 2010) were contrasted by warmer air temperature and presence of flood water in 2010. The seasonal average r_c values for common reed, …

P95. In Vivo Loads In The Cervical Spine: A Preliminary Investigation Using A Force-Sensing Implant, Rebecca A. Wachs, Mary Beth M. Grabowsky, Joseph C. Glennon, Eric H. Ledet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

BACKGROUND CONTEXT: It is estimated that up to 80% of the general population will experience at least one significant bout of low back pain in their lifetime. The leading known cause of low back pain is degenerative disc disease (DDD). Many established risk factors for low back pain and DDD are mechanical in nature and are often related to occupational activities, such as poor posture and frequent/heavy lifting. Altered mechanical loading in the spine has been shown to be a potential stimulus for disc degeneration. However, a link between occupational/environmental factors and intervertebral loading has never been demonstrated in vivo. …

Curcumin-Loaded Magnetic Nanoparticles For Breast Cancer Therapeutics And Imaging Applications, Murali M. Yallapu, Shadi F. Othman, Evan T. Curtis, Nichole A. Bauer, Neeraj Chauhan, Deepak Kumar, Meena Jaggi, Subhash C. Chauhan

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Breast cancer is a commonly diagnosed cancer among women in the United States. It is estimated that 230,480 women were diagnosed with, and 39,520 women died from, breast cancer in 2011 in the United States.¹ Basal-like breast cancer accounts for 15% of all breast cancers and has a poor prognosis. The majority of these cancers are referred to as triple-negative breast cancers because they do not over express estrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2.^2,3 Chemotherapy is an effective option to treat such cancers; however, chemotherapy is always associated with several sets of side …

Head Ejection During Barrier Impacts, Scott K. Rosenbaugh, Ronald K. Faller, Dean L. Sicking

Department of Civil and Environmental Engineering: Faculty Publications

During oblique vehicular impacts with longitudinal barriers, an occupant’s head is often ejected out of a side window. When this occurs, the occupant’s head can contact the barrier or an object attached thereto. This impact event, often termed head slap, normally produces a serious injury or fatality. Roadside barriers and any attached hardware should be designed with sufficient offset at the top to preclude head slap for most impact conditions. The goal of this study was to identify the extent of head ejection that can be expected during high-speed crashes with longitudinal barriers. High-speed videos of full-scale vehicle crash tests …

Drop Weight Testing On Sandwich Panels With A Novel Thermoplastic Core Material, Christopher Y. Tuan

Department of Civil and Environmental Engineering: Faculty Publications

A series of drop weight tests were conducted to evaluate the dynamic flatwise compression strength and flexural strength of sandwich panels with a novel core structure. This sandwich core material, known as Norcore, consists of interconnected cells in a unique configuration of truncated pyramid with sloping cell walls. Core materials made of thermoplastic including virgin Lexan, polycarbonate, polycarbonate regrind, high-impact polystyrene, and acrylonitrile butadiene styrene were tested. The test results showed that these sandwich panels have good strength as well as energy absorption capacities.

Evaluation Of Ice-Melting Capacities Of Deicing Chemicals, B. M. Gerbino-Bevins, Christopher Y. Tuan, M. Mattison

Department of Civil and Environmental Engineering: Faculty Publications

Common deicing chemicals include sodium chloride, magnesium chloride, calcium chloride, calcium magnesium acetate, potassium acetate, potassium formate, and corn or beet-based deicer solution. Liquid deicers are commonly used for pre-wetting road salt, sand or other solid deicers, or mixed with salt brine as liquid deicer. Although manufacturers provide performance data under specific conditions, a standardized test is very much needed. Samples of sodium chloride, magnesium chloride, calcium chloride, potassium acetate, and beet juice-based chemical deicers were selected for performance evaluation. The SHRP Ice-Melting Capacity Test has been used in many research projects, but the results do not always correlate well …

Development Of Self-Stressing System For Bridge Application With Emphasis On Precast Panel Deck System, Marcelo Ferreira Da Silva

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

Steel girder bridges often utilize continuity over the pier to reduce interior forces on the spans. In continuous structures with composite concrete decks, the location of maximum negative bending moment is over the interior supports. This moment produces tensile stresses in the concrete deck and compressive stress in the bottom flanges of the girders. The tensile stress in the deck leads to cracking which allow intrusion of moisture and road salt, causing corrosion of the reinforcement and supporting girders. Continued maintenance is required to forestall the deterioration; however, replacement of the deck is eventually required.

To overcome this problem, a …

Determining A Community Retrofit Strategy For The Aging Housing Stock Using Utility And Assessor Data, Nathan A. Barry

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

Residential buildings account for about 21.5% of the nation’s primary energy consumption and carbon emissions, and about 38% of electricity use. The housing stock in the United States consists of over 128 million residences with over 60% being constructed prior to 1979 when building codes and regulations began standardizing building practices. Seeking an opportunity to understand and reduce consumption, the scientific community developed a number of model-driven auditing software. While these computer models have been successful in predicting usage patterns in newer residential structures, they have been inaccurate in predicting and analyzing energy use in aging housing stock, predominantly homes …

Virtual Microstructure Generation Of Asphaltic Mixtures, Mohammad Haft-Javaherian

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

This thesis describes the development and application of a virtual microstructure generator incorporated with post-processing image analysis methods that can be used to fabricate a virtual, two-dimensional microstructure of asphaltic mixtures. In the generator, geometrical characteristics such as aggregate gradation, aggregate area fraction, angularity, orientation, and elongation were used to transform data from a three-dimensional (3D) mixture into its two-dimensional (2D) microstructure. The 2D virtual microstructures were generated from real 3D mixture information of asphaltic composites. Resulting virtual microstructures were then compared to real cross-sectional microstructure images obtained from actual samples for validation. Comparison presented a good agreement between the …

Phase I Development Of A Non-Proprietary, Four-Cable, High Tension Median Barrier, Mitchell J. Wiebelhaus, Dean L. Sicking, Ronald K. Faller, Karla A. Lechtenberg, John R. Rohde, Robert W. Bielenberg, Scott Rosenbaugh, Erin A. Johnson, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Evaluation Of The In-Service Safety Performance Of Safety-Shape And Vertical Concrete Barriers, Francisco Daniel Benicio De Albuquerque, Dean L. Sicking

Nebraska Department of Transportation: Research Reports

No abstract provided.

Water Quality Models For Stormwater Runoff In Two Lincoln, Nebraska Urban Watersheds, Jake Fisher

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

Water quality monitoring was conducted in two urban watersheds (Colonial Hills and Taylor Park) located in southeast Lincoln, NE over a three year period spanning from October 2008 through September 2011. In-line probes continuously measured for turbidity, conductivity, dissolved oxygen, and water temperature while other water quality constituents were analyzed for discrete water samples collected using grab and automatic sampling techniques. The water quality data was used to calculate event mean concentrations (EMCs) for sixteen storm events sampled over the duration of the project period. Three types of stormwater quality multiple linear regression models were developed for the estimation of …

Water Quality Monitoring Of An Urban Stream For Total Maximum Daily Load Assessment, Jeffrey K. Mihulka

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

The purpose of this research project was to assess the water quality of an urban stream for total maximum daily load assessment in Omaha, Nebraska. This was accomplished by sampling the water quality at four different sites. These sites included sampling upstream, within, and downstream of the city. These samples were conducted throughout 2010 and 2011.

The results showed that concentrations of Escherichia coli (E. coli) are routinely above established criteria for the state of Nebraska. Concentrations of E. coli that exist in the Papillion Creek Watershed upstream of the City of Omaha have also been shown to be above …

Development Of A State Of The Art Traffic Microsimulation Model For Nebraska, Justice Appiah, Bhaven Naik, Laurence Rilett, Yifeng Chen, Seung-Jun Kim

Nebraska Department of Transportation: Research Reports

No abstract provided.

Evaluation Of Ndor's Actuated Advance Warning Systems, Justice Appiah, Laurence Rilett, Zifeng Wu

Nebraska Department of Transportation: Research Reports

No abstract provided.

The Effects Of Pedestrian Countdown Timers On Safety And Efficiency Of Operations At Signalized Inersections, Anuj Sharma, Jacob Schmitz

Nebraska Department of Transportation: Research Reports

No abstract provided.

Evaluating The Cost-Effectiveness Of Roadside Culvert Treatments, Francisco Daniel B. De Albuquerque, Dean L. Sicking, Ronald K. Faller, Karla A. Lechtenberg

Department of Civil and Environmental Engineering: Faculty Publications

Roadside cross-drainage culverts have been found to affect vehicle accident injury levels. As a result, highway designers have commonly used three safety treatments to protect errant motorists from striking culvert openings. These safety treatments have included: culvert extension, guardrail installation, and the application of safety grating. However, the identification of the most appropriate safety treatment for roadside culverts may be challenging; accident costs may dramatically change under different road and traffic characteristics. The purpose of this study was to estimate accident costs for a wide range of road and traffic scenarios and then define the safest treatment (i.e., treatment with …

Sensitivity Analysis On Mapping Evapotranspiration At High Resolution Using Internal Calibration (Metric), Venkata Naga Ravi Kumar Choragudi

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

Mapping EvapoTranspiration at high Resolution using Internal Calibration (METRIC) is most widely used to quantify evapotranspiration (ET) spatially and temporally. It is essential to inspect the model’s response to errors in various parameters used in the model. Landsat 5 images from May 30 2009, July 1 2009 and a Landsat 7 image from September 27 2009 are used in this study. Fourteen different fields composed of Corn, Soybeans, Alfalfa are randomly chosen for each crop type.

Two kinds of errors are addressed in this study. One, with the errors that are transferred and potentially compensated by calibration (Global error) and …

Development Of A Design Procedure For Concrete Traffic Barrier Attachments To Bridge Decks Utilizing Epoxy Concrete Anchors, Benjamin J. Dickey

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

A guide for the design of epoxy anchors for the use in concrete traffic barriers was developed in this study. A series of dynamic bogie tests and static tests was conducted on single and double anchors. The dynamic increase factor for the noted anchors was determined to be 1.06. Protective epoxy coatings for the anchors was observed to contribute to a 9 percent decrease in anchorage strength. The effects of anchors located in close proximity to each other was also investigated. Calibration factors were developed to apply recommended changes to the ACI code for use in bridge rail anchorages.

A …

Expanding The Length Of Jointless Bridges By Providing Rotational Capacity Over The Pile Head, Ardalan Sherafati

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

Jointless bridges have been in service for more than 50 years. Since no expansion joint is utilized in these structures, they have longer service life, reduced maintenance and construction costs, improved riding quality, and added redundancy. Because of integrity of the superstructure with the substructure, the thermal movements as well as other longitudinal movements are transferred to substructure. These lateral movements can induce relatively large forces and moments in the substructure elements including the abutment and the piles. Typically, flexible foundations which include single row of piles are preferred in jointless bridges to reduce the stiffness of the system against …

Hydrologic Evaluation Of Established Rain Gardens In Lincoln, Nebraska Using A Storm Runoff Simulator, Andrew R. Anderson

Department of Environmental Engineering: Theses and Other Student Research

Increased urbanization has resulted in water quality and flooding problems for many receiving waters in the United States. Bioretention, or rain gardens, is one of the most widely popular and effective best management practices in low impact development (LID), which strives to return a watershed to a predevelopment hydrologic regime. Many studies have evaluated large bioretention cells in research settings. There is little information on the effectiveness of homeowner-maintained rain gardens that rely on deep percolation as the method for water exfiltration. Additionally, few studies address rain garden performance in cold, arid, or semi-arid climates found in the Midwest U.S. …

Wim Based Load Models For Bridge Serviceability Limit States, Przemyslaw Rakoczy

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

The safety of aging bridge inventory is one of the main concerns of the state and federal agencies. Therefore, there is a need to quantify the safety margin of existing infrastructure and new design bridges. The Serviceability Limit States, i.e. fatigue, requires additional statistical parameters and not only the maximum values but also load spectra, i.e. frequency of occurrence of loads. The maximum values are needed for shorter time periods, such as day, week, month or year. Load spectra as well as material resistance are random variables. To quantify the safety margin of existing and future bridges load and resistance …

Development Of Alternative Wood-Post Mgs Approach Guardrail Transition, Scott K. Rosenbaugh, Kevin D. Schrum, Ronald K. Faller, Karla A. Lechtenberg, Dean L. Sicking, John D. Reid

Nebraska Department of Transportation: Research Reports

No abstract provided.

Extending Integral Concepts To Curved Bridge Systems, Saeed Eghtedar Doust

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

The behavior of integral abutment systems and the extension of their application to curved bridges are investigated. First, the stresses in the elements of a typical integral abutment are studied by conducting nonlinear finite element analysis using the software package Abaqus. The results are design recommendations for the details of such abutments. The effect of integral abutments on the responses of bridges is also investigated. Steel and concrete bridge systems are studied separately.

The studied steel bridge systems are composed of composite I-girder superstructures and integral abutments supported on steel H-piles. A series of finite element studies for different bridge …

Seamless Bridge And Roadway System For The U.S. Practice, Nima Ala

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

Expansion joints are one of the main causes for high maintenance costs in bridges. The search for ideal expansion joints has proven fruitless. That is why it has been said that “the best joint is no joint”. A seamless bridge system is envisioned that results in bridges with long service lives by eliminating the joints over the entire length of the bridge, approach slab and a segment of the roadway called transition. All bridge thermal movements are dissipated to zero in the transition. The system is similar to a system developed in Australia but modifications had to be made to …

History Of The Biological Systems Engineering Program In Nebraska, University Of Nebraska-Lincoln, William E. Splinter

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Farm Machinery/Agricultural Engineering/Biological Systems Engineering program current and former faculty members at the University of Nebraska, as demonstrated here, has made a statewide, national, and worldwide impact on the efficient production of food. The quality of this recognition is evidenced best by peer professionals through recognized ASABE awards received by Nebraska alumni or professors. Since its inception in 1909 and until 2010, there have been 10 national presidents, 19 gold medal recipients and 33 named national award recipients. Currently there are 31 ASABE Fellows and two members of the National Academy of Engineering. This national recognition comes as a …

Model For Predicting The Impact Upon Economic Development Resulting From Highway Improvement Projects, Eric Thompson, Kanou Comlavi, Mallory Dimmit

Nebraska Department of Transportation: Research Reports

The Nebraska Department of Roads (NDOR) has an interest in integrating state economic development impact as another factor in prioritizing transportation investments. Such efforts require the development of a comprehensive model that can be used to estimate a consistent final measure of economic development impact that can be readily integrated into existing prioritization formulas. This report summarizes the efforts of the University of Nebraska-Lincoln Bureau of Business Research (UNL-BBR) to develop such a model, by measuring the impact of expressway, viaduct, and other major investments projects around the state. Specifically, UNL-BBR developed an economic model to predict the economic impact …

Stage-Dependent Transient Storage Of Phosphorus In Alluvial Floodplains, Derek M. Heeren, Garey A. Fox, Ronald B. Miller, Daniel E. Storm, Amanda K. Fox, Chad J. Penn, Todd Halihan, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Models for contaminant transport in streams commonly idealize transient storage as a well-mixed but immobile system. These transient storage models capture rapid (near-stream) hyporheic storage and transport, but do not account for large-scale, stage-dependent interaction with the alluvial aquifer. The objective of this research was to document transient storage of phosphorus (P) in coarse gravel alluvium potentially influenced by large-scale, stage-dependent preferential flow pathways (PFPs). Long-term monitoring was performed at floodplain sites adjacent to the Barren Fork Creek and Honey Creek in northeastern Oklahoma. Based on results from subsurface electrical resistivity mapping which was correlated to hydraulic conductivity data, observation …