Transportation Engineering Commons^™

Feasibility Study: Application Of Steel Sheet-Piles For The Abutment Of Water-Crossing Bridges In Nebraska, Seunghee Kim, Jongwan Eun, Chung R. Song, Chungwook Sim, Hung Phi Van, Basil Abualshar, Ramin Ziaei Tabari

Nebraska Department of Transportation: Research Reports

The overall goal of this study is to investigate the anticipated performance of steel sheet-pile bridge abutments to encourage its wider application to not only new construction but also repair and replacement of existing water-crossing bridges in Nebraska. For this purpose, this study first reviewed several bridge cases with axially loaded sheet pile abutments, as well as previous in-depth studies related to the bearing capacity of sheet piles. Then, this study conducted the large-scale direct shear tests to better understand the interaction between sheet pile and soil. As a result, about four-fifths of the internal friction angle of fill sand …

Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell

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

Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system …

Establishment Of Wildflower Islands To Enhance Roadside Health, Ecological Value, And Aesthetics Phase Ii, Jackson Ebbers, Heidi L. Hillhouse, John A. Guretsky, Thomas J. Weissling

Nebraska Department of Transportation: Research Reports

No abstract provided.

Performance Of High Early-Strength Materials Used In Concrete Bridge Repair, Zina Ebrahim, Fray F. Pozo-Lora, Zachary Benson, Mohammad Mastali, Marc Maguire, Jiong Hu

Nebraska Department of Transportation: Research Reports

High early-strength materials are widely used for rapid concrete patching projects to limit road closure time and traffic obstruction. This research investigated the field performance of multiple high early-strength materials used in maintenance projects across Nebraska. Data from high early-strength products included in the state’s approved product list were collected and compared to field performance. In addition, a survey was prepared and distributed to the surrounding states to understand standard practices related to appropriate specifications of these materials that can be later used to develop specifications for the utilization of high early strength materials in Nebraska based on experimental and …

Uhpc Decked I-Beam For Accelerated Bridge Construction, George Morcous, Maher K. Tadros

Nebraska Department of Transportation: Research Reports

Ultra-High-Performance Concrete (UHPC) is an excellent material for bridge construction due to its exceptional durability and superior mechanical properties. Several Departments of Transportations (DOTs), including NDOT, have limited the use of UHPC in bridge construction to joints and connections between bridge components due to the relatively high materials cost of commercially UHPC products. Recently, NDOT has sponsored a research project to develop a non-proprietary UHPC using local materials to reduce materials cost and ensure its availability to local contractors and precast producers. The project was completed successfully and an economical UHPC mix that satisfied all workability, durability, and strength requirements …

The Effects Of Inaccurate And Missing Highway-Rail Grade Crossing Inventory Data On Crash Model Estimation And Crash Prediction, Aemal Khattak, M. Umer Farooq

Mid-America Transportation Center: Final Reports and Technical Briefs

ABSTRACT: Most highway-rail grade crossing (HRGC) crash models in the US rely on the Federal Railroad Administration’s (FRA) highway/rail crossing inventory database. Any errors and/or incomplete information in this database affects the estimated crash model parameters and subsequent crash predictions. Using 560 HRGCs in Nebraska, this study illustrates differences in crash predictions obtained from the FRA’s new (2020) Accident Prediction and Severity (APS) model when: 1) using the unaltered, original FRA HRGC inventory dataset as input, and 2) using a field-validated inventory dataset for those 560 HRGCs as input to the new APS model. Results showed that the predictions using …

Motor Vehicle Drivers' Knowledge Of Safely Traversing Highway-Rail Grade Crossings, Aemal Khattak, M. Umer Farooq, Abdul Farhan

Mid-America Transportation Center: Final Reports and Technical Briefs

This study investigates motor vehicle drivers’ socioeconomic, personality, and attitudinal factors associated with their knowledge of safely traversing highway-rail grade crossings (HRGCs). A survey of randomly selected Nebraska households solicited responses from licensed drivers (N= 980, response rate = 39 percent). Of the total thirty-one questions on the questionnaire, nine pertained to respondents’ knowledge of safely navigating HRGCs (e.g., what does a crossbuck sign require a driver to do when approaching a rail crossing?). Correct answers to the questions provided a measure of respondents’ knowledge of safely traversing HRGCs and led to their classification in five ordered categories. A random …

A Heterogeneity-Based Temporal Stability Assessment Of Pedestrian Crash Injury Severity Using An Aggregated Crash And Hospital Data Set, M. Umer Farooq, Aemal Khattak

Mid-America Transportation Center: Final Reports and Technical Briefs

This study utilized a unique approach to crash data analysis by examining the temporal stability of pedestrian crash injury severity and its contributory factors. Police-reported crash data and EMS-related injury data from Nebraska were obtained from 2014 to 2018, and random parameter ordered probit models for injury severity were estimated for each year to account for unobserved heterogeneity. Four discrete levels of injury severity were considered for model estimation: fatality, disabling injury/suspected serious injury, visible injury/possible injury, and no injury. Data were filtered based on several important variables of interest, such as pedestrian characteristics, crash characteristics, environmental and weather characteristics, …

Field Monitoring Of Joint-Less Curved Integral Abutment Bridge In Nebraska, Ramin Ziaei, Yusuf Alhowaidi, Chungwook Sim, Jongwan Eun, Seunghee Kim, Chung Rak Song

Nebraska Department of Transportation: Research Reports

The research objective of this project is to study the behavior of the curved full integral abutment bridge designed in Nebraska through field monitoring and numerical simulation to 1) understand and model the complex short-term and long-term behavior of curved integral abutment bridges, 2) evaluate if the details provided in Nebraska (pile embedment over 4 ft into the abutment) can be expanded for wider design and construction practices (longer spans and larger curvature for curved bridges), and 3) better maintain existing full curved integral bridges in Nebraska based on the findings of this study (revise and optimize design, if needed). …

Phased Construction Bridges: Monitoring And Analysis For Traffic-Induced Vibration, Khalid Al-Kady, Christine E. Wittich, Richard L. Wood, George Morcous

Nebraska Department of Transportation: Research Reports

Phased construction is a common technique utilized to allow bridges to remain partially open to traffic throughout the construction process. The segment of the bridge deck that is constructed second cures under the effect of traffic-induced vibration transmitted from the adjacent bridge-deck segment, which is open to traffic. However, subjecting bridge decks to traffic-induced vibration during early-age curing raises concerns about the durability of the decks. The primary goal of this study is to generate a fundamental understanding of the transmission of traffic-induced vibration, the extent of degradation on phased construction bridge decks, and the impact of potential mitigation measures. …

Outdoor Laboratory And Testbed For Bridge Health, Richard L. Wood, Mitra Nasimi, Bowen Yang, Christine E. Wittich, Joshua Steelman, Jay Puckett, Daniel Linzell, Jinying Zhu, Mohammad Ebrahim Mohammadi

Nebraska Department of Transportation: Research Reports

Due to the aging problem of bridges and the limited financial resources in the United States, it is necessary to form a deeper understanding of existing, aging bridges in an effort to extend their in-service life. To address this problem, researchers from the University of Nebraska-Lincoln (UNL) and engineers from the Nebraska Department of Transportation (NDOT) identified three, out-of-service bridges (two steel and one concrete) to establish the Nebraska Outdoor Bridge Lab (NOBL). As the first step in NOBL’s development, geometric surveys of the current condition of each bridge were produced using lidar and Structure-from-Motion (SfM). This data contributed to …

Data-Driven Prioritization And Empirical Predictions For Bridge Scour In Nebraska, Richard L. Wood, Awgku Ahmad Hashim B. Awg Bolhasan, Basil Abualshar, Christine E. Wittich, Chung R. Song, Junke Guo, Mohammad Ebrahim Mohammadi, Mitra Nasimi, Yijun Liao

Nebraska Department of Transportation: Research Reports

The effect of scour at the bridge substructure results in an increase in the vulnerability of the overall bridge stability. Previous studies have found that current guidelines are often overly-conservative with respect to scour. This project aims to provide guidance on hydraulic modeling parameters and reasonable scour estimates specific to Nebraska conditions. This will enable engineers to assess bridge sites for scour more precisely for efficient and effective design and countermeasures. Four sites were surveyed for scour changes between the period of December 9, 2020, to April 20, 2021. At these four sites, overland and bathymetry survey data were collected. …

Intelligent Work Zone Using Automatic Queue Detection Systems, Li Zhao, Laurence Rilett, Ernest Tufuor

Nebraska Department of Transportation: Research Reports

This report documents the the evaluation of the effectiveness of the Advanced Queue Detection (AQD) systems installed on Interstate work zones in Nebraska. Specifically, (1) the system performance was verified by examining whether the messages displayed on the portable dynamic message signs (PDMS) were consistent with the underlying AQD logic; (2) the system efficacy was measured by determining whether driver speeds were reduced when warning messages were provided on the PDMS; and (3) the system safety impact was modeled using statistical models. It was found that overall, the AQD systems had an error rate of 0.7% – 2.3%. Drivers reduced …

An Investigation Of Water Obstructions And Related Weather Conditions For Nebraska Roadways, Mark R. Anderson, Logan R. Bundy

Nebraska Department of Transportation: Research Reports

Roadway resilience across the 10,000 miles of road and 3,500 bridges in Nebraska is critical to the economic success of productionand logistics. In a state where historical flooding scenarios, such as the one in March 2019 that caused $150 million in damage,could potentially be increasing, it has become essential to understand the spatial and temporal distribution of high-frequency waterobstruction areas on roadways. Therefore, in order to further investigate these areas, the main objectives of this research were toperform statistical and spatial analyses to quantify the relationship between water obstructions and their associated meteorologicalconditions, and identify the potential linkages between water …

Estimating System And Traveler Costs Due To Lane Closures During Construction And Maintenance Operations, Ernest Tufuor, Li Zhao, Mm Haque, Laurence Rilett Ph.D., John Anderson, Eric Thompson

Nebraska Department of Transportation: Research Reports

Lane closures are used to facilitate activities related to road construction and maintenance or operations. However, there are economic costs associated with lane closures and these may accrue to both the traveling public as well as to traffic agencies. The Nebraska Governor’s office has identified maximizing the effectiveness of lane closures as a priority for the Nebraska Department of Transportation (NDOT). The goal of this project is to assist NDOT in effectively managing the operations of work zones to maximize the effectiveness of lane closures under Nebraska conditions. This report summarizes the findings of the current state of the practice …

Estimating System And Traveler Costs Due To Lane Closures During Construction And Maintenance Operations, Ernest Tufuor, Lianlin Zhao, Mm Shakiul Haque, Laurence Rilett, John Anderson, Eric Thompson

Nebraska Department of Transportation: Research Reports

Lane closures are used to facilitate activities related to road construction and maintenance or operations. However, there are economic costs associated with lane closures and these may accrue to both the traveling public as well as to traffic agencies. The Nebraska Governor’s office has identified maximizing the effectiveness of lane closures as a priority for the Nebraska Department of Transportation (NDOT). The goal of this project is to assist NDOT in effectively managing the operations of work zones to maximize the effectiveness of lane closures under Nebraska conditions. This report summarizes the findings of the current state of the practice …

Exploration Of The Characteristics And Trends Of Electric Vehicle Crashes: A Case Study In Norway, Chenhui Liu, Li Zhao, Chaoru Lu

Mid-America Transportation Center: Final Reports and Technical Briefs

With the rapid growth of electric vehicles (EVs) in the past decade, many new traffic safety challenges are also emerging. With the crash data of Norway from 2011 to 2018, this study gives an overview of the status quo of EV crashes. In the survey period, the proportion of EV crashes in total traffic crashes had risen from zero to 3.11% in Norway. However, in terms of severity, EV crashes do not show statistically significant differences from the Internal Combustion Engine Vehicle (ICEV) crashes. Compared to ICEV crashes, the occurrence of EV crashes features on weekday peak hours, urban areas, …

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Program: Senior Projects (Public)

The following project report was a study of the North 14^th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14^th Street and the 14^th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …

Research On High-Rap Mixtures With Rejuvenator - Field Implementation, Nitish R. Bastola, Mahdieh Khedmati, Hamzeh Haghshenas

Nebraska Department of Transportation: Research Reports

The use of Rejuvenating Agents (RAs), as Recycled Asphalt Pavement (RAP) modifiers, has been increasing over the past years. However, the field performance of asphalt mixtures containing high-RAP materials and modified with RAs has raised some concerns regarding the long-term performance of RAs. This study evaluated the laboratory and field performance of high-RAP mixtures with and without bio-oil RA. Three sets of plant-produced specimens were collected: 1) laboratory-compacted; 2) field-compacted and cored after paving; and 3) field-compacted and cored after one and two years. The Hamburg Wheel Tracking (HWT) test was used to evaluate the specimens' resistance to rutting and …

Measuring Foundation Course Modulus Using Falling Weight Deflectometer, Light Weight Deflectometer, And Dynamic Cone Penetration, Bruce Barrett, Kellie Troxel, Brady Dresselhaus, David Hansen

Nebraska Department of Transportation: Research Reports

Phase I results showed that FWD, LWD, and DCP provided valid results and trended with each other at the stations all three tests were run. This gives confidence that any test method is reliable when used on an exposed bituminous foundation course.

The results of Phase I and Phase II indicate that using FWD testing after concrete is built does not provide an accurate modulus of the foundation course. As demonstrated through the statistical analysis, foundation course moduli cannot be reliably calculated by using FWD on top of doweled concrete pavements and back-calculated using Darwin software or ME Design. Additionally, …

Measuring Foundation Course Modulus Using Falling Weight Deflectometer, Light Weight Deflectometer, And Dynamic Cone Penetration, Bruce Barrett, Kellie Troxel, Brady Dresselhaus, David Hansen

Nebraska Department of Transportation: Research Reports

The purpose of this investigation was to determine the feasibility of measuring bituminous foundation course modulus under concrete roadways by comparing testing results derived before and after paving using FWD, Light Weight Deflectometer (LWD), and Dynamic Cone Penetrometer (DCP). The foundation course modulus was determined using FWD data and Darwin design software (‘93 AASHTO). Results from Phase I data collection, which occurred prior to pavement placement, provided a baseline for comparison. The maximum modulus was 398,000 PSI and the minimum was 85,000 PSI, yielding a range of 315,000 PSI and an average modulus of 123,000 PSI over the length of …

Https://Dot.Nebraska.Gov/Media/4yaemfil/M100-Nebraska-Buried-Archeological-Sites-Phase-Ii.Pdf, Anthony L. Layzell, Rolfe D. Mandel, Courtney L. Ziska, John R. Bozell

Nebraska Department of Transportation: Research Reports

This project developed a GIS to assist with the identification of deeply buried archeological sites in alluvial settings across Nebraska with the exception of the Sandhills region. Soil survey data, previous geoarcheological investigations, landform position, and other information was used to rank the potential of any stream valley setting as low, low-moderate, moderate-high, or high potential to contain buried soils (paleosols). While the presence of buried soils does not necessarily translate to presence of buried archeological sites, the potential for such sites is far greater in paleosols. The GIS can be used by NDOT and other agencies with statutory historic …

Design And Detailing Of Cast-In-Place And Precast Concrete Approach Slabs, George Morcous, Mostafa Abo-Elkhier

Nebraska Department of Transportation: Research Reports

Approach slab is a structural concrete slab that spans from the backwall of the abutment (i.e. end of the bridge floor) to the beginning of the paving section. The purpose of the approach slab is to carry the traffic loads over the backfill behind the abutments to avoid differential settlement that causes bumps at the bridge ends. Cast- in-place concrete approach slab is the current practice in US with various spans, reinforcement, thicknesses, joints, and concrete covers. NDOT has observed premature cracking in a significant number of approach slabs, which could result in a shorter service life and costly repairs/replacements …

Design And Detailing Of Cast-In-Place And Precast Concrete Approach Slabs, George Morcous Ph.D., Mostafa Abo-Elkhier

Nebraska Department of Transportation: Research Reports

Approach slab is a structural concrete slab that spans from the backwall of the abutment (i.e. end of the bridge floor) to the beginning of the paving section. The purpose of the approach slab is to carry the traffic loads over the backfill behind the abutments to avoid differential settlement that causes bumps at the bridge ends. Cast-in-place concrete approach slab is the current practice in US with various spans, reinforcement, thicknesses, joints, and concrete covers. NDOT has observed premature cracking in a significant number of approach slabs, which could result in a shorter service life and costly repairs/replacements as …

Research And Education For Optimizing The Development And Implementation Of An Unmanned Aircraft Program At The Nebraska Department Of Transportation, Wayne Woldt, Jon Starr, Christopher M. U. Neale

Nebraska Department of Transportation: Research Reports

This report describes the development and implementation of an Unmanned Aircraft System Program at the Nebraska Department of Transportation (NDOT). The project involved the selection and purchase of appropriate UAS and imaging systems for NDOT, education and training for NDOT personnel with classroom and hands-on operation of UAS with the goal of obtaining proficiency and pilot licenses. In addition, the development of policy for the use of UAS within NDOT was accomplished as well as standard operating procedures (SOP) documentation and the development of example case studies of interest to NDOT using the purchased systems and technology.

Research And Education For Optimizing The Development And Implementation Of An Unmanned Aircraft Program At The Nebraska Department Of Transportation, Wayne Woldt, Jon Starr, C.M.U. Neale

Nebraska Department of Transportation: Research Reports

This report describes the development and implementation of an Unmanned Aircraft System Program at the Nebraska Department of Transportation (NDOT). The project involved the selection and purchase of appropriate UAS and imaging systems for NDOT, education and training for NDOT personnel with classroom and hands-on operation of UAS with the goal of obtaining proficiency and pilot licenses. In addition, the development of policy for the use of UAS within NDOT was accomplished as well as standard operating procedures (SOP) documentation and the development of example case studies of interest to NDOT using the purchased systems and technology.

Field Demonstration Of Gpr And Uav Technologies For Evaluation Of Two Us 75/77 Bridges, Sepehr Pashoutani, Jinying Zhu, Chungwook Sim, Ji-Yong Lee

Nebraska Department of Transportation: Research Reports

Two Nebraska bridges with asphalt overlay were selected for nondestructive testing and evaluation (NDT/NDE). Three NDT techniques were conducted on these two bridges, including Ground Penetrating Radar (GPR), Half-Cell Potential (HCP) and Unmanned Aerial Vehicle (UAV) imaging. NDT data were collected during three construction stages of the bridges: (1) before repair on existing asphalt overlay; (2) on bare concrete after asphalt removal; (3) and after repairing delaminated concrete.

A machine learning technique, autoencoder, was used to build quantitative relationships between different NDT datasets. On bare concrete, the GPR amplitude and HCP voltage show a strong linear relationship. Then a threshold …

Feasibility Study: Alternatives To Prevent Settlements And Bumps At Bridge Approach, Seunghee Kim, Jongwan Eun, Yusuf Alhowaidi, Daniel Robertson

Nebraska Department of Transportation: Research Reports

This project aims to examine the feasibility of improving the current design practice of the approach slab foundation in Nebraska and the alternative of using geosynthetic reinforcement of soils to prevent the bump issues near the end of bridge approaches via an in-depth numerical simulation study. A large-scale pullout test is also conducted as complementary to provide input parameters for the interaction between the regional soil and selected geosynthetics. Based on the results, it is recommended that the number of grade beam piles could be reduced to 40-50 % of the total number of abutment piles while maintaining the same …

Evaluating Asct Operations For Dodge Street Corridor, Anuj Sharma, Subhadipto Poddar, Atousa Zarindast, Christopher Day

Nebraska Department of Transportation: Research Reports

As Adaptive Traffic Control (ATC) is increasingly being implemented by various traffic agencies, careful evaluation is needed of the degree to which a given ATC implementation improves traffic signal performance. The present study details the evaluation of ATC for two arterial corridors in the City of Omaha, Nebraska. Several performance measures were used across two stages of ATC implementation as well as during the unanticipated COVID-19 lockdown stage.

The average travel time and variability in travel time showed that Stage 1 of ATC implementation in Omaha did not improve traffic signal performance for the study’s main corridor, Dodge Street. This …

A Methodology For Estimating Capacity And Passenger Car Equivalents For Connected And Automated Vehicles Traveling On Freeways, Antonio Hurtado Beltran

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

Recently, there has been a significant amount of research related to heavy trucks operating as connected and autonomous vehicles (CAVs). In order to understand the potential impact on the freeway system of CAV technologies, analyses should be conducted using the standard US methodological framework. In the current version of the Highway Capacity Manual (HCM-6), equal-capacity passenger car equivalencies (EC-PCEs) are used to account for the effect of heavy trucks on capacity and quality of service analyses. It is argued in this dissertation the HCM-6 EC-PCE methodology for basic freeway and multilane highway segments can be used to explore a wide …