Engineering Commons^™

Analyzing Major Elements Of Crash Injury Severity Involving Priority-I Detriments Of Vision-Zero Plan, Muhammad Umer Farooq, Cole Madson, Aemal Khattak

Mid-America Transportation Center: Final Reports and Technical Briefs

Road traffic crashes result in significant economic losses for individuals, their families, and entire nations. These losses stem from the expenses associated with injury treatment, as well as the productivity lost due to fatalities or disabilities caused by these injuries. The 2030 Agenda for Sustainable Development set an ambitious target of halving the global number of fatalities and injuries from road traffic crashes by 2020 and achieving zero deaths by 2030, commonly referred to as the 'Target Zero Plan.' The Target Zero Plan prioritizes traffic safety issues into three distinct levels. The three priority levels are determined based on the …

Road Work Zone Safety: Investigating Injury Severity In Motor Vehicle Crashes Using Random Effects Multinomial Logit Model, Aemal Khattak, Muhammad Umer Farooq

Mid-America Transportation Center: Final Reports and Technical Briefs

Work zones serve the purpose of facilitating maintenance and rehabilitation activities on roadways. However, these areas can also present unforeseen conditions to drivers, including narrowed right-of-way, lane shifts, and traffic disruptions. These conditions frequently contribute to vehicular crashes within work zones, resulting in property damage, injuries, and even loss of life. This paper aims to highlight work zone related crash data insights and presents statistical estimates of significant determinants of injury severity by analyzing ten-year crash data (2008-2018) from Nebraska, USA. The examination of crash data helped in highlighting work zone attributes that are empirically associated with serious injury crashes …

Exploring Statistical And Machine Learning-Based Missing Data Imputation Methods To Improve Crash Frequency Prediction Models For Highway-Rail Grade Crossings, Muhammad Umer Farooq, Aemal Khattak

Mid-America Transportation Center: Final Reports and Technical Briefs

Highway-rail grade crossings (HRGCs) are critical spatial locations of transportation safety because crashes at HRGCs are often catastrophic, potentially causing several injuries and fatalities. Every year in the United States, a significant number of crashes occur at these crossings, prompting local and state organizations to engage in safety analysis and estimate crash frequency prediction models for resource allocation. These models provide valuable insights into safety and risk mitigation strategies for HRGCs. Furthermore, the estimation of these models is based on inventory details of HRGCs, and their quality is crucial for reliable crash predictions. However, many of these models exclude crossings …

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, …

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 …

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 …

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, …

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

Mid-America Transportation Center: Final Reports and Technical Briefs

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

Optfill: A Tool For Infeasible Cycle-Free Gapfilling Of Stoichiometric Metabolic Models, Wheaton L. Schroeder, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Stoichiometric metabolic modeling, particularly genome-scale models (GSMs), is now an indispens- able tool for systems biology. The model reconstruction process typically involves collecting informa- tion from public databases; however, incomplete systems knowledge leaves gaps in any reconstruc- tion. Current tools for addressing gaps use databases of biochemical functionalities to address gaps on a per-metabolite basis and can provide multiple solutions but cannot avoid thermodynami- cally infeasible cycles (TICs), invariably requiring lengthy manual curation. To address these limita- tions, this work introduces an optimization-based multi-step method named OptFill, which performs TIC-avoiding whole-model gapfilling. We applied OptFill to three fictional prokaryotic models …

Corrigendum To “Heavy Metal Ion Detection On A Microspot Electrode Using An Optical Electrochemical Probe” [Electrochem. Commun. 86 (2018) 94–98], Santanu Roy, Abhijeet Prasad, Rahul Tevatia, Ravi Saraf

Mid-America Transportation Center: Final Reports and Technical Briefs

The authors regret to inform an error. Ravi F. Saraf of this pub- lication discloses financial interest in Vajra Instrument as its founder and President. In accordance with its Conflict of Interest policy, the University of Nebraska-Lincoln’s Conflict of Interest in Research Committee has determined that this must be disclosed. The authors would like to apologise for any inconvenience caused.

An Integrated Computational And Experimental Study To Investigate Staphylococcus Aureus Metabolism, Mohammad Mazharul Islam, Vinai C. Thomas, Matthew Van Beek, Jong-Sam Ahn, Abdulelah A. Alqarzaee, Chunyi Zhou, Paul D. Fey, Kenneth W. Bayles, Rajib Saha

Mid-America Transportation Center: Final Reports and Technical Briefs

Staphylococcus aureus is a metabolically versatile pathogen that colonizes nearly all organs of the human body. A detailed and comprehensive knowledge of staphylococcal metabolism is essential to understand its pathogenesis. To this end, we have reconstructed and experimentally validated an updated and enhanced genome-scale metabolic model of S. aureus USA300_FPR3757. The model combined genome annotation data, reaction stoichiometry, and regulation information from biochemical databases and previous strain-specific models. Reactions in the model were checked and fixed to ensure chemical balance and thermodynamic consistency. To further refine the model, growth assessment of 1920 nonessential mutants from the Nebraska Transposon Mutant Library …

Calibrating The Highway Capacity Manual Arterial Travel Time Reliability Model, Ernest Tufuor, Laurence Rilett, Li Zhao

Mid-America Transportation Center: Final Reports and Technical Briefs

The latest edition of the Highway Capacity Manual (HCM-6) includes, for the first time, a methodology for estimating and predicting the average travel time distribution (TTD) of urban streets. Travel time reliability (TTR) metrics can then be estimated from the TTD. The HCM-6 explicitly considers five key sources of travel time variability. A literature search showed no evidence that the HCM-6 TTR model has ever been calibrated with empirical travel time data. More importantly, previous research showed that the HCM-6 underestimated the empirical TTD variability by 70% on a testbed in Lincoln, Nebraska. In other words, the HCM-6 TTR metrics …

Analysis Of Component Errors In The Highway Capacity Manual Travel Time Reliability Estimations For Urban Streets, Ernest Tufuor, Laurence Rilett

Mid-America Transportation Center: Final Reports and Technical Briefs

The Highway Capacity Manual 6th edition (HCM6) includes a new methodology to estimate and predict the distribution of average travel times (TTD) for urban streets. The TTD can then be used to estimate travel time reliability (TTR) metrics. Previous research on a 0.5-mi testbed showed statistically significant differences between the HCM6 estimated TTD and the corresponding empirical TTD. The difference in average travel time was 4 s that, while statistically significant, is not important from a practical perspective. More importantly, the TTD variance was underestimated by 70%. In other words, the HCM6 results reflected a more reliable testbed than field …

Validation Of The Highway Capacity Manual Urban Street Travel Time Reliability Methodology Using Empirical Data, Ernest Tufuor, Laurence Rilett

Mid-America Transportation Center: Final Reports and Technical Briefs

The 6th edition of the Highway Capacity Manual (HCM-6) includes the concept of travel time reliability (TTR), which attempts to determine the distribution of average trip travel times over an extended period. TTR is an inherent part of travelers’ route choice decisions and is used by traffic managers to better quantify operations rather than simply using average travel times. The focus of this paper is on the HCM-6 urban street TTR methodology contained in Chapter 17. The approach uses historical data (e.g., weather and volume fluctuations) and simple empirical data (e.g., 1-day volume count) to provide the user with average …

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 …

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, …

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 …

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 …

Phase I Assessment Of Guardrail Length-Of-Need, Francisco Daniel B. Albuquerque, Cody S. Stolle, Dean L. Sicking, Ronald K. Faller, Karla A. Lechtenberg

Mid-America Transportation Center: Final Reports and Technical Briefs

Report No. TRP-03-284-14

Roadside Grading Guidance - Phase Ii, Kevin D. Schrum, Francisco D. B. Albuquerque, Dean L. Sicking, Ronald K. Faller, John D. Reid

Mid-America Transportation Center: Final Reports and Technical Briefs

Phase I of this project relied on assumptions surrounding crash data from the state of Ohio in 2000. The number of fatal and severe crashes in that year was significantly lower than average. As a result, the conclusions were indefinite. Phase II was carried out using crash data from the state of Ohio over seven years. The increased pool of data removed the need for many of the underlying assumptions used in Phase I and provided a solid foundation of conclusions and recommendations.

The number of fatal and severe crashes that occurred on each slope and height for each functional …

Development Of A Field Test Method For Total Suspended Solids Analysis, Tian Zhang, John S. Stansbury, Jessica Branigan

Mid-America Transportation Center: Final Reports and Technical Briefs

Total suspended solids (TSS) are all particles in water that will not pass through a glass fiber filter with a pore size less than 2 μm, including sediments, algae, nutrients, and metals. TSS is an important water quality parameter because of its adverse effects on aquatic species and wildlife. TSS is regulated through the EPA via the NPDES in many states. Since there are no accepted field tests for TSS, projects with TSS regulations must send samples to a laboratory for analysis, which can delay projects for days or weeks. The goal of this research was to develop a rapid, …

Calibration Of Work Zone Impact Analysis Software For Missouri, Praveen Edara Ph.D., P.E., Ptoe, Carlos Sun Ph.D., P.E., Jd, Zhongyuan Zhu

Mid-America Transportation Center: Final Reports and Technical Briefs

This project calibrated two software programs used for estimating the traffic impacts of work zones. The WZ Spreadsheet and VISSIM programs were recommended in a previous study by the authors. The two programs were calibrated using field data from two work zones in Missouri. Both work zones involved a single lane closure on a three-lane section of roadway. The I-44 work zone was a long-term work zone, while the I-70 work zone was temporary, lasting only a few hours. The capacity values required for calibration were nearly identical for the two programs: 1,575 veh/hr/ln for the WZ Spreadsheet and 1,514 …

Evaluation Of J-Turn Intersection Design Performance In Missouri, Final Report, Praveen Edara Ph.D., P.E., Ptoe, Carlos Sun Ph.D., P.E., Jd, Sawyer Breslow

Mid-America Transportation Center: Final Reports and Technical Briefs

Research shows that a high percentage of crashes that take place on high-speed rural expressways occur at intersections with minor roads. One low-cost alternative design for improving the safety of at-grade intersections on such expressways is the J-turn. In the last few years, the Missouri Department of Transportation has converted some two-way stop controlled (TWSC) intersections into J-turns. This study evaluated the effectiveness of the J-turn intersection design in Missouri utilizing field studies, a public survey, crash analysis, and traffic conflict analysis. The field studies collected detailed video data at a J-turn site and a control site. The crash analysis …

Investigation Of Alternative Work Zone Merging Sign Configurations, Praveen Edara Ph.D., P.E., Ptoe, Zhongyuan Zhu, Carlos Sun Ph.D., P.E., Jd

Mid-America Transportation Center: Final Reports and Technical Briefs

This study investigated the effect of an alternative merge sign configuration within a freeway work zone. In this alternative configuration, the graphical lane closed sign from the MUTCD was compared with a MERGE/arrow sign on one side and a RIGHT LANE CLOSED sign on the other side. The study measured driver behavior characteristics including speeds and open lane occupancies. The measurements were taken at two identical work zones on I-70 in Missouri, one with the new test sign and the other with the standard MUTCD sign. The study found that the open lane occupancy upstream of the merge sign was …

Investigation Of Synergistic Effects Of Warm Mix Asphalt And High Fractionated Reclaimed Asphalt For Safe, Environmentally Sustainable Highway, Hosin David Lee Ph.D., P.E., Taha Ahmed Msc, E.I.

Mid-America Transportation Center: Final Reports and Technical Briefs

To increase RAP materials by up to 75% by binder replacement, a fractionation method was applied to the RAP stockpile by discarding RAP materials passing No. 16 sieve. This fractionation method was effective in improving volumetric properties of the HMA mixture with high RAP contents. The mix designs were then performed for both HMA and WMA with varying fractionated RAP amounts accounting for a replacement of 20, 30, 40, 50 and 75% of the mixture’s optimum asphalt binder content. All mix designs met the Iowa DOT mix design requirements except the one with 75% RAP materials by binder replacement due …

Towards Autonomous Vehicles, Chris Schwarz Ph.D., Geb Thomas Ph.D., Kory Nelson B.S, Michael Mccrary B.S., Nicholas Schlarmann, Matthew Powell

Mid-America Transportation Center: Final Reports and Technical Briefs

We are moving towards an age of autonomous vehicles. Cycles of innovation initiated in the public and private sectors have led one into another since the 1990s; and out of these efforts have sprung a variety of Advanced Driver Assistance Systems and several functioning autonomous vehicles. The challenges that face autonomous vehicle are still significant. There is still technical work to be done to make sensors, algorithms, control schemes, and intelligence more effective and more reliable. As automation in vehicles increases, the associated human factors challenges become more complex. Then, there are a host of socioeconomic issues. Are autonomous vehicles …

New Highway Accident Location Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Praveen Edara Ph.D., P.E., Ptoe, Henry Brown M.S., P.E.

Mid-America Transportation Center: Final Reports and Technical Briefs

The Missouri HAL manual is used to identify, analyze, and correct high crash locations, and has not been updated since 1999. This new edition brings the manual up to date, while incorporating the methodology of the national Highway Safety Manual (HSM). This 4th edition represents a complete re-working of all existing chapters of the manual. The changes are both stylistic and substantive. A contemporary book-style stylesheet was used to improve the appearance of figures, tables, headings, and labels. Even the title of the manual was changed from HAL (Identification, Analysis, and Correction of High-Crash Locations) to S-HAL (Safety Handbook for …

Development Of A Guide For Prioritization Of Railway Bridges For Repair And Replacement, Anna Maria Rakoczy, Andrzej S. Nowak

Mid-America Transportation Center: Final Reports and Technical Briefs

The objective of this study was to develop evaluation bases for the repair, rehabilitation, and replacement of existing railway bridges. Considering the importance of bridges to the railway network, the research involved the review and analysis of major factors that influence structural performance, e.g., degree of corrosion, loss of material (section loss, holes), fatigue problems, and loose connections. In particular, the research focused on connections, and their importance relative to the evaluation of bridge performance. The relationship between various conditions and the ability to perform the required function (i.e., carry a freight train) was established in the form of maximum …

Calibration Of The Highway Safety Manual For Missouri, Carlos Sun Ph.D., P.E., Jd, Henry Brown Msce, P.E., Praveen Edara Ph.D., P.E., Boris Carlos, Kyuongmin Andrew Nam

Mid-America Transportation Center: Final Reports and Technical Briefs

The new Highway Safety Manual (HSM) contains predictive models that need to be calibrated to local conditions. This calibration process requires detailed data types, such as crash frequencies, traffic volumes, geometrics, and land-use. The HSM does not document in detail techniques for gathering such data, since data systems vary significantly across states. The calibration process also requires certain decisions, such as the correct sampling approach, determination of the minimum segment length, the treatment of left-turn phasing, and the inclusion or exclusion of speed-change lane crashes. This report describes the challenges, practical solutions, and results from a statewide HSM calibration in …

Development Of System Reliability Models For Railway Bridges, Andrzej S. Nowak Ph.D., Anna Maria Rakoczy Ph.D.

Mid-America Transportation Center: Final Reports and Technical Briefs

Performance of the railway transportation network depends on the reliability of railway bridges, which can be affected by various forms of deterioration and extreme environmental conditions. More than half of the railway bridges in US were built before 1950 and many show signs of distress. There is a need for efficient methods to evaluate the safety reserve in the railway bridges by identification of the most sensitive parts of the bridge. An accurate estimation of remaining fatigue life of a structural component is very important in prioritizing bridge rehabilitation and replacement. However, existing procedures to evaluate the fatigue behavior of …