Transportation Engineering Commons^™

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 …

Impact Of Covid-19 On City Streets, Mihir Sharma

Honors Scholar Theses

Covid-19 has had a severe impact on the urban fabric of many cities and caused disruption to the current way of living. This paper attempts to shed light on the impact that Covid-19 has had on the city streets and how city streets have adapted to the disruptions brought on by the virus. Furthermore the paper lays down recommendations that cities can use to make their streets healthier and safer

Analysis, Modeling, And Simulation (Ams) Case Studies Of Connected And Automated Vehicle (Cav) Implementations Specific To The South Central Region, Christopher Melson, Jiaqi Ma

Publications

Connected and automated vehicles (CAVs) offer potentially transformative and far-reaching impacts to the transportation system. However, realized benefits will be directly tied to how well agencies prepare for these technologies. This report documents efforts that support CAV preparatory actions in Louisiana and includes: (1) conducting a stakeholder survey to inform engagement activities to develop strategic partnerships in CAV deployment and (2) conducting crash analyses for deployment scenarios of CAV-based queue warning systems (QWSs).

An electronic survey was developed and disseminated to 273 Louisiana organizations. The purpose of the survey was to engage these organizations under the context of CAV planning …

Supporting Transportation System Management And Operations Using Internet Of Things Technology, Hong Yang, Yuzhong Shen, Mecit Cetin, Zhenyu Wang

Computational Modeling & Simulation Engineering Faculty Publications

Low power wide-area network (LPWAN) technology aims to provide long range and low power wireless communication. It can serve as an alternative technology for data transmissions in many application scenarios (e.g., parking monitoring and remote flood sensing). In order to explore its feasibility in transportation systems, this project conducted a review of relevant literature to understand the current status of LPWAN applications. An online survey that targeted professionals concerned with transportation was also developed to elicit input about their experiences in using LPWAN technology for their projects. The literature review and survey results showed that LPWAN’s application in the U.S. …

Improving Logistics Efficiency Through Collaborative Truck Routing, Patrick Dougherty

Industrial Engineering Undergraduate Honors Theses

The logistics industry is among the world’s largest and most essential. Specifically, trucking is a massive component of the modern logistics system. In 2012, truck transportation carried 68% of all freight tonnage in the U.S. However, trucking currently faces significant problems with efficiency and sustainability. Of all miles driven by trucks yearly in the U.S., 25% are driven with empty loads and 36% are driven with underutilized loads. In addition to this economic inefficiency, the industry faces social and environmental challenges. Driver turnover rates are near 100%, and trucking accounts for a significant level of greenhouse gas emissions. One potential …

Going Green: A Comparative Analysis Of Green Urbanism In Paris And Shanghai, Jeanne Torp

Honors Theses

As climate change becomes more pressing with each day and as we scramble to slow down the challenges it poses, adapting the means of operation within our cities will become an invaluable tool for reducing humanity’s carbon footprint. This paper seeks to study the ways in which green infrastructure in global cities can be used to do just that—adapting to and mitigating the effects of challenges resulting from climate change. In order to provide a broad overview of the effectiveness of such green infrastructure systems across the globe, this research will focus on two cities that vary greatly in their …

Fatal Crashes At Highway Rail Grade Crossings: A U.S. Based Study, Subasish Das, Xiaoqiang Kong, Steven M. Lavrenz, Lingtao Wu, Mohammad Jalayer

Henry M. Rowan College of Engineering Departmental Research

Crashes at highway rail grade crossings (HRGCs) are often involved with fatalities due to the momentum of a train. This study collected nine years (2010–2018) of fatal HRGC crashes from the Fatality Analysis Reporting System (FARS) to perform the analysis. The Taxicab Correspondence Analysis (TCA) was applied to this dataset. This method identified several patterns that trigger HRGC-related fatal crashes. The findings indicate that fatal crashes involving multiple fatalities are often highly associated with alcohol-influenced drivers, poor lighting conditions, and inclement weather. The fatal crash that occurs during the daylight with the uninfluenced driver is less likely to involve more …

Abrasion Resistance Of Ultra-High-Performance Concrete For Railway Sleepers, Ariful Hasnat, Nader Ghafoori

Civil and Environmental Engineering and Construction Faculty Research

This study aimed to determine the abrasion resistance of ultra-high-performance concretes (UHPCs) for railway sleepers. Test samples were made with different cementitious material combinations and varying steel fiber contents and shapes, using conventional fine aggregate. A total of 25 UHPCs and two high-strength concretes (HSCs) were selected to evaluate their depth of wear and bulk properties. The results of the coefficient of variation (CV), relative gain in abrasion, and abrasion index of the studied UHPCs were also obtained and discussed. Furthermore, a comparison was made on the resistance to wear of the selected UHPCs with those of the HSCs typically …

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 …

Nighttime Pedestrian Fatalities Across The United States And Their Relationship With Built Environment And Socioeconomic Factors: Gis-Based Analysis And Assessment, Amir Tarighi

Civil Engineering ETDs

Fatalities from motor vehicle collisions are the fifth leading cause of years of lost life worldwide (Foreman et al., 2018) and are a great concern for all communities. This road safety crisis has been especially pronounced for U.S. pedestrians over the last decade. National records show that between 2010 and 2019, pedestrian fatalities in the U.S. increased 44% while all other traffic fatalities increased only 4% and more than fifty percent of pedestrian fatalities occurred in dark lighting conditions. This study analyzed the relationship between pedestrian fatality locations at night and five demographic characteristics of those locations including population density, …

Modeling Bus Bunching And Anti-Bunching Control Accounting For Signal Control And Passenger Swapping Behavior, Qi Xin, Rui Fu, Shaowei Yu, Satish V. Ukkusuri, Rui Jiang

Journal of Public Transportation

The conventional bus propagation process has two main shortcomings: one is bus bunching, the other is extra energy consumption by idling at signalized intersection and unexpected speed variation along the route. To overcome these problems simultaneously, an extended bus propagation model and an anti-bunching control are proposed. To extend the time-based bus propagation model, we employ finite state machine and intelligent driver model to establish a spatial-temporal based bus propagation model accounting for bus dynamic motion and passenger swapping behavior between bunching buses. To mitigate bus bunching and improve bus fuel economy in a cyber-traffic environment, an anticipated average speed …

Evaluation Of Permanent Concrete Barriers To Mash 2016, Samuel Elias Hovde

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

The objective of this research project was to develop evaluation criteria for permanent concrete barriers to MASH 2016 TL-3 and TL-4 without crash testing and then to evaluate permanent concrete barrier standards provided by the sponsoring agencies of the Midwest Pooled Fund Program. A literature review was conducted to determine evaluation criteria for stability, shape, strength, and anchorage, and a database of permanent concrete barrier crash tests was compiled. A survey was conducted to collect barrier standards from the members of the Midwest Pooled Fund Program, and barriers were selected and evaluated according to the determined methodology. A total of …

Intersection Redesign For Network Resilience And Safety, Antonio Pratelli, Pietro Leandri, Rosaria Aiello, Reginald R. Souleyrette

Civil Engineering Faculty Publications

This paper describes a procedure for improving the resilience of roadway networks. A methodology is outlined that develops a time-dependent and performance-based resilience index. This methodology was applied to an Italian road, with the aim of optimizing intersections that are critical due to inadequate baseline capacity. The methodology uses a calibrated microscopic traffic model (using Aimsun™) whereby average delay at intersection approaches are estimated by an analytical model. From the simulation, average speed over time is obtained for each approach. These values in turn are used as inputs for calculating each intersection’s resilience index. The procedure allows the identification of …

Laboratory Evaluation Of Geogrid-Reinforced Flexible Pavements, Mohammad Reza Sharbaf, Nader Ghafoori

Civil and Environmental Engineering and Construction Faculty Research

This study assessed the effectiveness of flexible pavements reinforced with two types of punched and drawn geogrids to reduce roadway base course thickness. Six laboratory tests were conducted using a steel cylindrical mold. Instrumentation included pressure cells placed at various locations of the test sections and a linear variable differential transformer which was placed on top of the loading system. A hydraulic actuator provided 40 kN (9 kips) cyclic load through a 305 mm (12 in) circular steel plate at a frequency of 0.77 Hz. Test results revealed that inclusion of both geogrid types in flexible pavement showed reductions in …

Distributionally Robust Optimization Utilizing Facility Location Problems, Elijah Kling

Civil and Environmental Engineering Undergraduate Honors Theses

Facility location problems are used in widespread application in transportation, freight, supply chain, and logistics problems. Models can be developed as deterministic, where all parameters are known, or robust, where a parameter has uncertainty. This thesis explores a new method for developing robust formulation and compares the implications of assuming values for this uncertain parameter. Two models are solved, and both are compared against their deterministic counterparts using numerical analysis. By manipulating the input parameters and considering real world implications of the solutions, either the robust or deterministic can show better performance.

Biopolymerized Slope/Subgrade Stabilization And Advanced Field Monitoring, Chung R. Song, Layla Bitar, Richard L. Wood, Yong-Rak Kim, Jongwan Eun, Binyam M. Bekele, Basil Abualshar

Nebraska Department of Transportation: Research Reports

The slightly overconsolidated glacial tills and weathered shales in Midwestern states of the USA often show substantial strength degradation after construction. This strength reduction often causes time dependent slope failures along the roadside. This study investigated the possibility of applying biopolymer based soil modification techniques to mitigate the strength reduction phenomenon of these soils. For this research, several different biopolymers were evaluated through laboratory tests, two biopolymers were selected for extensive weathering tests, then a higher-performing biopolymer, Xanthan, was applied to a test slope in Verdigre, Nebraska with heavy instrumentation. The followings are the summary of the results.

The unweathered …

Maximum Coverage Facility Location Drone Routing Problem With Multiple Trip Stops, Marie Roza

Civil and Environmental Engineering Undergraduate Honors Theses

Integer linear optimization can be used to formulate routing problems as models to find optimal solutions given a set of inputs and constraints. In this research, Chauhan et al.'s publication, "Maximum coverage capacitated facility location problem with range constrained drones," is expanded upon by modeling a facility location problem with two-to-one drone deliveries. The model analyzes a set of potential facilities that are available to meet the demands of a set of demand points. The drone delivery routes are modeled with the assumption that each opened facility is assigned one drone that can fulfill up to two demand points’ demands …

The Role Of Rejuvenators In Embedded Damage Healing For Asphalt Pavement, Shi Xu, Xueyan Liu, Amir Tabakovic, P Lin, Y Zhang, S Nahar, B J. Lommerts, Erik Schlangen

Articles

Rejuvenator encapsulation technique showed great potential for extrinsic asphalt pavement damage healing. Once the capsules are embedded within asphalt pavement, the healing is activated on-demand via progressing microcrack. When the microcrack encounters the capsule, the fracture energy at the tip opens the capsule and releases the rejuvenator. Then the released rejuvenator wets the crack surfaces, diffuses into and softens the aged bitumen, allowing two broken edges to come in the contact, preventing further asphalt pavement deterioration. The quality and speed of the damage repair process strongly depend on the quality of rejuvenator, thus it is important to choose a proper …

City Best Practices To Improve Transit Operations And Safety, Michelle Derobertis, Christopher E. Ferrell, Richard W. Lee, David Moore

Mineta Transportation Institute

Public, fixed-route transit services most commonly operate on public streets. In addition, transit passengers must use sidewalks to access transit stops and stations. However, streets and sidewalks are under the jurisdiction of municipalities, not transit agencies. Various municipal policies, practices, and decisions affect transit operations, rider convenience, and passenger safety. Thus, these government entities have an important influence over the quality, safety, and convenience of transit services in their jurisdictions. This research identified municipal policies and practices that affect public transport providers’ ability to deliver transit services. They were found from a comprehensive literature review, interviews and discussions with five …