Civil Engineering Commons^™

Optimizing Steel Railway Truss Bridge Health Monitoring, Ahmed Rageh, Daniel Linzell

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

Problems - Steel Railway Trusses • Aging • Large system – bridge AND railway • Labor intensive condition eval • Reported conditions: Stringer-to-floor beam connections [Haghani 2012] Stringer flange clip angle cracks [Haghani 2012] Unequal eyebars stress distribution [DelGrego 2008] Displaced eyebar pins [DelGrego 2008

Problems – Condition Evaluation • Visual inspection: Prescribed frequency Costly Subjected to human interpretation • Sensors: Focused on a single bridge Extensive array Costly

Influence Of Skew And Nonlinear Deck On Elastic Versus Inelastic Distribution Behavior And Ultimate Capacity Of Steel Girder Bridges, Fayaz Sofi, Joshua Steelman

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

Research Objectives

• Assessment of alternative load distribution methodologies for potential discrepancies that arise when evaluating distribution behavior of skewed steel girder bridges.

• Investigate the influence of skew and material nonlinearities (concrete cracking and steel yielding) on

• Load distribution behavior (elastic versus inelastic).

• System capacities (yielding and ultimate).

Summary and Conclusions • Influence of skew was examined on load distribution behavior, and nonlinear system-based capacities (yielding and ultimate) of composite steel girder bridges in presence of full material nonlinearities. In addition, assessment of two general definitions (beam-line and response fraction approaches) for quantifying load distribution behavior was …

Design And Implementation Of The Manitoba Constrained-Width Tall Wall Barrier, Harald P. Larsen, Scott K. Rosenbaugh, Andrew Pankratz, Diana Emerson, Jennifer Schmidt, Ronald K. Faller, Elizabeth M. Regier

Mid-America Transportation Center: Final Reports and Technical Briefs

Manitoba Infrastructure (MI) desired a new, tall concrete median barrier capable of satisfying the Test Level 5 (TL-5) safety requirements of the Manual for Assessing Safety Hardware (MASH). It needed to fit within the footprint of an existing F-shape median barrier located in a narrow median. It also was required to address headlight glare from opposing traffic. The barrier was designed with a height of 1,250 mm, a maximum width of 600 mm and to resist a load of 845 kN applied at the top of the barrier. The Manitoba Constrained-Width, Tall Wall was optimised to withstand the design load …

Cive 463: Traffic Engineering—A Peer Review Of Teaching Project Benchmark Portfolio, John Sangster

UNL Faculty Course Portfolios

This course portfolio documents the backward design of a senior-level design elective course in traffic engineering within the Department of Civil Engineering at the University of Nebraska. An extensive discussion of stakeholder needs for the course is followed by an analysis of formative and summative feedback assessments that are designed to meet the needs of a heterogeneous group of students in the course. As a senior-level design elective, there is a wide variety of interest levels among participants in the course, varying from those who have experience with internships in the topic and offer letters to conduct work in this …

Development Of A Test Level 3 Transition Between Guardrail And Portable Concrete Barriers, Robert W. Bielenberg, David Gutierrez, Ronald K. Faller, John D. Reid, Phil Tenhulzen

Department of Civil and Environmental Engineering: Faculty Publications

Road construction often requires that work zones be created and shielded by portable concrete barriers (PCBs) to protect workers and equipment from errant vehicles as well as to prevent motorists from striking other roadside hazards. For an existing W-beam guardrail system installed adjacent to the roadway and near the work zone, guardrail sections are removed so a PCB system can be placed. A study was done to develop a crashworthy transition between W-beam guardrail and PCB systems. Design concepts were developed and refined through computer simulation with LS-DYNA. Additionally, a study of critical impact points was conducted to determine impact …

How Acoustics In California High Performance Schools Relate To Student Achievement, Devin K. Wong

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This research project seeks to determine if students attending K–12 schools meeting a minimum standard of high performance classroom conditions in the state of California do evidence higher scholastic achievement, based on publically available results on state-wide standardized tests. In three phases, a subset of 200+ schools applying for grants dedicated to building high performance schools over the past decade was correlated with an existing database of achievement scores for all public schools in California. The criteria utilized to specify high performance classrooms was provided by the California High Performance Initiative (HPI) Grant program. Academic achievement was evaluated on a …

Development And Assessment Of A Groundwater Sustainability Index In Climatically Diverse Groundwater Irrigated Regions In Nebraska, Maria A. Mulet Jalil

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The aim of this research was to evaluate the impact of regional change in ET on groundwater level changes and the assessment and development of a groundwater sustainability index for climatically diverse regions across Nebraska during 2000-2014. Irrigation in the selected regions is predominantly supplied by groundwater. The hypothesis is that groundwater use can become sustainable if the regional evapotranspiration (ET) is managed so that it equals the ET of vegetation that is native to the region. Site locations were Box Butte, Chase, Dundy, Holt LNNRD and York Counties and 3 ecosystems were evaluated: native vegetation, dryland and irrigated cropping …

Cfd Study Of Decay Function Of Wall Shear Stress With Scour Around Complex-Shape Bridge Pier, Chen Li

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

Pier scour problem is close related to the safety of bridges. The Federal Highway Administration of the United State also has a great interest in studying the relation between hydraulic loadings and scour depth. The current technological problem of directly measuring hydraulic loadings on a dynamic bed using physical experiments and the weak capacity to simulate the real scour processes with CFD methods inspired the development of a hybrid approach by combining them to study pier scour.

This research specifically focuses on the CFD part of the hybrid method. A series of three-dimensional (3-D) CFD models were developed with unsteady …

The Experiment And Analysis Of Active Mechanisms For Enhancing Heat And Mass Transfer In Sorption Fluids, Ziqi Shen

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This project was funded by American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE RP-1462). It is a three years’ research, including the literature review, labs construction, experiments and data analysis.

In this thesis, first of all, we conducted literature review of mechanism motion influence on heat and mass transfer and additive effect in absorption chiller. This part helps us understand the basic idea of how mechanism motion affects the heat and mass transfer of sorption fluids and gives us reference on how to select the experiment instrument and the experiment operation range.

In the second part, the instrument selection …

An Investigation Of Motor Vehicle Driver Inattention And Its Effects At Highway–Rail Grade Crossings, Shanshan Zhao

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

The relationship between accident injury severity and drivers’ inattentive behavior requires an in-depth investigation – this is especially needed in the case of motor vehicle drivers at highway-rail grade crossings (HRGCs). The relationship between drivers’ personality/ socioeconomic characteristics and inattentive behavior at HRGCs is another topic requiring research. Past educational programs about safe driving at HRGCs have often not been designed to target people who may be in urgent need of such information, which may limit the effectiveness of those programs.

This dissertation thus focuses on the following four objectives: to investigate the association between motor vehicle inattentive driving and …

Microbial Degradation Of Sulfonamide Antibiotics, Rachel Levine

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

Certain microbes can transform antibiotics in the environment. However, little is known about the identity of these microbes and their antibiotic biotransformation processes. The objectives of this study were to (1) isolate bacterial strains capable of transforming antibiotics, (2) determine the biotransformation kinetics of antibiotics, (3) characterize the effects of background carbons on the biotransformation kinetics, and (4) identify biotransformation products under various environmental conditions. Sulfadiazine (SDZ) was used as the model antibiotic in this study due to its frequent occurrence in livestock wastes. Surface soil from a cattle feedlot was collected to enrich potential SDZ degrading bacteria. A mixed …

Multiscale Research Toward Resilient Civil Infrastructure, Hamzeh Haghshenas Fatmehsari, Keyvan Zare Rami, Mahdieh Khedmati, Kommidi Santosh, Farshad Fallah, Yong-Rak Kim

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

Infrastructure materials are generally composite in nature and consist of different phases. Despite their widespread use, the mechanisms behind their behavior are often not fully understood. The aim of this research is to develop the capability to predict the performance of infrastructure based on its components, thus eliminating the need for costly experimental tests. Such an objective requires thorough understanding of material properties at various length-scales and investigation of the linkage between each scale. This approach can lead to more optimized designs, sustainable performance and maximized public benefit

A Five-Year Performance Review Of Field-Scale, Slow-Release Permanganate Candles With Recommendations For Second-Generation Improvements, Mark Christenson, Ann Kambhu, James Reece, Steve D. Comfort, Laurie Brunner

Nebraska Water Center: Faculty Publications

In 2009, we identified a TCE plume at an abandoned landfill that was located in a low permeable siltyclay aquifer. To treat the TCE, we manufactured slow-release potassium permanganate cylinders (oxidant candles) that had diameters of either 5.1 or 7.6 cm and were 91.4 cm long. In 2010, we compared two methods of candle installation by inserting equal masses of the oxidant candles (7.6-cm vs 5.1-cm dia). The 5.1-cm dia candles were inserted with direct-push rods while the 7.6-cm candles were housed in screens and lowered into 10 permanent wells. Since installation, the 7.6-cm oxidant candles have been refurbished approximately …

Recent Morphodynamic Evolution Of The Largest Uninhibited Island In The Yangtze (Changjiang) Estuary During 1998-2014: Influence Of The Anthropogenic Interference, Wen Wei, Xuefei Mei, Zhijun Dai, Zhenghong Tang

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Estuarine geomorphology worldwide has greatly changed in the Anthropocene due to intensive human inferences in river basin and within estuary, which has received increasing global concerns. Here, recent morphodynamic evolution of Jiuduan Shoal (JDS), the largest uninhabited island in the Yangtze (Changjiang) Estuary, and associated controlling factors were analyzed based on unique high-resolution seasonal-surveyed bathymetric data during 1998–2014. It can be indicated that JDS presents novel 12 and 48 months fluctuations though significant accretion was detected on high flats above −2 m. Meanwhile, morphodynamic evolution of JDS during 1998–2014 was divided into three stages: significant siltation on land-ward half of …

Field-Scale Testing And Numerical Investigation Of Soil-Boulder Interaction Under Vehicular Impact Using Fem And Coupled Fem-Sph Formulations, Lynsey Reese, Tong Qiu, Daniel Linzell, Zoltan Rado

Department of Civil and Environmental Engineering: Faculty Publications

A computational approach that couples the Finite Element Method and the Smoothed Particle Hydrodynamics method may be advantageous for simulating the response of complex, physical systems involving large deformations. However, comparisons of this modeling technique against field-scale test data are remarkably sparse in literature. This study presents three field-scale tests involving vehicular impact into three landscape vehicular anti-ram barriers. Each barrier consisted of a single boulder embedded in compacted American Association of State Highway and Transportation Officials soil and physical testing resulted in one of the following outcomes: minimal boulder/soil movement (Test 1), moderate boulder/soil movement (Test 2), and severe …

Expedient Airfield Runway Repair Using Folded Fiberglass Mat, Christopher Y. Tuan, Willaim C. Dass

Department of Civil and Environmental Engineering: Faculty Publications

For expedient airfield runway repair, the US Air Force has developed a folded fiberglass mat to cover craters repaired with a well-compacted granular base material. The objective of this study was to evaluate the adequacy of using polymer plugs to anchor the mat to a repaired asphalt pavement for heavy aircraft operations. The effort consisted of materials testing, field experiments and analytical modeling. An 89,800-kg (198,000-pound) load cart having the footprint of a single C-5 main gear was pulled on a mat with wheels locked to simulate full braking forces. Anchor bushings were instrumented to measure anchor loads. A simplified …

Feasibility Of Using Raman-Based Techniques For Breast Cancer Detection, Sara Mollamohammada

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

Breast cancer is one of the common types of cancer among women all over the world. Early diagnosis is an effective way that improve the treatment process and gives the patients a better chance of survival. Many of the patients infected by breast cancer choose breast conservation surgery (BCS). However, some of those will be subjected to mastectomy, and many will have tumor recurrence as there is no precise technique to show the tumor margins. Raman-based methods are powerful techniques with potential to rapidly differentiate normal from tumor tissues and provides a solution to detect tumor margin. This is because …

Dynamic Characteristics And Seismic Response Analysis Of A Long-Span Steel-Box Basket-Handle Railway Arch Bridge, Xuhui He, Biao Wei, Yunfeng Zou, Dongyang Hu, Daniel G. Linzell

Department of Civil and Environmental Engineering: Faculty Publications

The inside oblique angle between the vertical plane and the arch rib has been shown to be one of the main factors influencing dynamic properties of long-span steel-box basket-handle arch bridges. Details related to the extent, that the inside oblique angle influenced the dynamic characteristics and the seismic response of the arch bridge under the combined longitudinal and vertical seismic excitation and under the combined lateral and vertical seismic excitation, were reported herein. Four oblique angles (0°, 3°, 4.8°, and 6°) were selected based on the arch ribs height and bridge deck width. Findings suggested that a larger inside oblique …

Velocity Distributions And Wall Pressures In A Scale Model Gated Box Culvert Control Structure, Alexander L. Evans

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

The South Florida Water Management District (SFWMD) manages a system of canals and structures that control the flow through several large storm water treatment areas (STA). The present project was initiated because of the partial failure of a three-barrel, gated box culvert structure that belongs to the system. The structure has a forebay with three sluice gates that control the flow into three 8 ft by 8 ft box culverts. Settling and partial failure of the culverts in the structure was presumably caused by piping of sediment through joints in pre-cast sections of culvert. It was hypothesized that both unsteady …

Best Practices For Winter Maintenance Roadway Deicer Applications In The State Of Nebraska, Tregan P. D. Albers Ii

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

The cost of deicing chemicals is a significant part of the Nebraska Department of Road’s winter maintenance budget. The objectives of this research are to review literature to determine current winter maintenance practices, analyze and present information gathered in a survey of winter maintenance professionals across Nebraska, and correlate this information with data obtained via MDSS (Maintenance Decision Support System) software to determine current practices being used in the state of Nebraska. Best practices for winter maintenance deicer applications for rural city and county officials in Nebraska are recommended. An explanation of the development of the survey that winter maintenance …

Conceptual Development Of An Impact-Attenuation System For Intersecting Roadways, Joseph G. Putjenter

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Longitudinal barriers are commonly used to shield hazards, including stiff bridge rail ends and slopes. In some locations, a secondary roadway intersects the primary roadway within the guardrail’s length-of-need (LON). Some intersections have as little as 15 ft (4.6 m) between the intersection and beginning of the bridge railing, which require short-radius guardrail systems. No short-radius systems have been tested and approved to current impact safety standards for shielding hazards with these conditions.

Site conditions provided by the Nebraska Department of Roads were used to determine the constraints for a new safety treatment for intersecting roadways and include intersection radii, …

Evaluating The Air Emissions From Solid Waste Refuse Trucks, Lauren D. Hauser

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

The air emissions from solid waste refuse trucks is an issue that has not been widely studied, but is becoming an ever increasing issue. In the United States alone they have generated around 251 million tons of waste in 2012. This study in particular will collect data on 24 different refuse trucks (front-load, side-load, and roll-off, and diesel and compressed natural gas fuel) while on real-life routes in the Raleigh, North Carolina area. The collected data will then be aggregated and summarized based on the type of trucks. A regression analysis will also be done to determine the relationship between …

Engineering Graphene Oxide Membranes For Contaminant Removal And Bacterial Inactivation, Stefan M. Schaepe

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

The need for improved water filtration technologies continues to grow on a global scale. Membrane filtration devices are increasing in use because they can remove a variety of contaminants efficiently. The major issue with membrane filters is biofouling. Coating membranes with nanoparticles such as graphene oxide (GO) can increase contaminant removal and decrease microbial growth.

This research characterizes the properties of the GO itself, two procedures for producing GO coated membranes, the properties of the created membranes and the contaminant removal and bactericidal efficiencies of the membranes. Pure water flux values for GO coated membranes prepared using a direct deposition …

Feasibility Analysis Of Phase Transition Signals Based On E-Bike Rider Behavior, Sheng Dong, Jibiao Zhou, Li Zhao, Keshuang Tang, Renfa Yang

Mid-America Transportation Center: Final Reports and Technical Briefs

This article evaluates the feasibility of two scenarios of phase transition signals, that is, the flashing green together with red–yellow light and the green countdown together with red countdown, at signalized intersections in terms of e-bike rider behavior. An evaluation framework is first proposed. During the phase transition, the stop-go and start-up behavioral parameters are collected at four intersections in Shanghai, China. Sensitivity analysis is then performed to identify the most significant factors that influence the occurrence of traffic conflicts during the phase transition. Based on the above analysis results, case studies were finally done to look into safety performance …

Attachment Of A Combination Bridge Rail To Concrete Parapet Utilizing Epoxy Adhesive Anchors, Robert W. Bielenberg, John D. Reid, Scott K. Rosenbaugh, Austin J. Haase, Ronald K. Faller

Mid-America Transportation Center: Final Reports and Technical Briefs

The Iowa Department of Transportation (IaDOT) was interested in investigating the use of epoxy adhesive anchorages

for the attachment of posts used in the BR27C combination bridge rail system. Alternative anchorage concepts were developed using a modified version of the ACI 318-11 procedures for embedded anchor design. Four design concepts were developed for review by IaDOT, including: (1) a four-bolt square anchorage, (2) a four-bolt spread anchorage, (3) a two- bolt centered anchorage, and (4) a two-bolt offset anchorage. IaDOT representatives selected the four-bolt spread anchorage and the two-bolt offset anchorage as the preferred designs for evaluation. In addition to …

Cable-To-Post Attachments For A Non-Proprietary High-Tension Cable Barrier – Phase Ii, Scott K. Rosenbaugh, Robert W. Bielenberg, Brandt M. Humphrey, Ronald K. Faller, John D. Reid, Karla A. Lechtenberg

Mid-America Transportation Center: Final Reports and Technical Briefs

The research objectives reported herein were based on further development of cable-to-post attachment hardware for use in the non-proprietary high-tension cable barrier system. Specifically, this project aimed to develop and evaluate alternative attachment designs for the bolted, tabbed bracket and evaluate the use of a larger diameter, keeper rod for use in the top cable attachment.

From a group of over 25 alternative attachment concepts, two tabbed bracket designs were selected for evaluation through dynamic component testing: 1) the lateral shear plate attachment and 2) the drop-in shear plate attachment. The drop-in shear plate concept did not perform as intended, …

An Investigation Into Bacterial Contamination In An Urban Nebraska Stream Using Microbial Source Tracking, Allison R. Speicher

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

High levels of fecal bacteria in surface waters are a public health concern due to the enteric illnesses caused by primary contact with these waters. Shortcomings in the current fecal indicator bacteria (FIB) monitoring approach and the ubiquity of pathogen-impaired water bodies has led to the development of microbial source tracking (MST), a molecular tool that can identify potential fecal contamination sources. In this study we use a bacterial community based approach examining the V4 region of the 16S rRNA gene to elucidate sources of fecal bacteria in Antelope Creek, an urban creek in Lincoln Nebraska.

We hypothesized that sediment …

Lidar Scanning With Supplementary Uav Captured Images For Structural Inspections, Richard L. Wood, Mohammad Ebrahim Mohammadi

Department of Civil and Environmental Engineering: Faculty Publications

Structural assessment using remote sensing technologies can be performed efficiently and effectively using such technologies as LiDAR (light detection and ranging). LiDAR can be employed for various structural assessments, such as as-built conditions for a newly constructed facility, routine inspection during its service life, or structural collapse evaluation after a natural hazard or extreme event. However, the main disadvantage of LiDAR is that it is a line-of-sight technology that can result in significant occlusions. Architectural or structural components can be partially or fully occluded by another object with respect to the location of the laser scanner. Supplemental photogrammetry techniques, such …

Gis-Based Route Risk Assessment Of Hazardous Material Transport, Myungwoo Lee

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

The transportation of hazardous materials keeps increasing across the United States due to the growing consumption of goods and rising need for manufactured materials. Furthermore, concerns are mounting over the safe surface transportation of hazardous materials. Highways and rails are the most common modes of transport for hazardous materials, although the risk posed from highway transport of hazardous materials may be higher due to the fact that highways are public while rails are mostly private. The majority of hazardous material cargo is carried on the highway network by trucks. Due to possible adverse effects on human and animal populations in …

A New Decision Making Approach For Indirect Left Turn Treatments By Utilizing Decision Assistance Curves, Sunil Gyawali

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

This study developed decision assistance curves (DAC) for unconventional intersections, including median U-turns (MUT), continuous flow intersections (CFI), and jughandle intersections, based on their operational performance relative to a conventional intersection. An economic analysis was performed to compute the net present value (NPV) of benefits and the benefit to cost ratio (B/C) with the development of a spreadsheet tool. The DAC classified the region of optimal performance of isolated unconventional intersections. For 5% left turn traffic conditions, MUT was warranted for all volume criteria. For 10% and 15% left turn traffic conditions, jughandle was warranted for the major street approach …