Engineering Commons^™

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 …

Enhancing Serviceability And Resiliency Of Transportation Networks Based On Topological Credentials And Systematic Design Interventions, Md Ashraf Ahmed

FIU Electronic Theses and Dissertations

Recent advancements in network science showed that the topological credentials (i.e., rank of relative importance) of network components (such as nodes and links), carry significant implications as it is critical to know which components contribute the most to the overall network performance. For transportation networks, critical components (roads, bridges) may become inaccessible for adjacent traffic due to day-to-day congestion or external disruptions (i.e., man-made or natural hazards) that significantly reduce the level of service. Hence, topological credentials of critical network components based on their connectivity need to be assessed to enhance the serviceability, i.e., improved travel time experience as well …

Vermont Transportation Energy Profile 2021, Jonathan Dowds, Dana Rowangould

University of Vermont Transportation Research Center

Slightly more than one-third of the total energy consumed in Vermont is used for transportation (see Figure E-1). Transportation energy is overwhelmingly derived from fossil fuels, with over 95% coming in the form of gasoline and diesel fuel. Transportation is also the largest source of greenhouse gas (GHG) emissions in the State, accounting for 39.1% GHGs in 2017.

Consequently, the 2016 Vermont Comprehensive Energy Plan (CEP) included three goals and nine supporting objectives related to reducing transportation sector energy consumption and GHG emissions (VDPS, 2016). The 2021 Vermont Transportation Energy Profile (“the Profile”) is the fifth installment of a biannual …

Understanding And Efficiently Managing Right-To-Take Challenges In Kentucky, Pam Clay-Young, Steve Waddle, Bryan Gibson

Kentucky Transportation Center Research Report

Executive Summary

Kentucky constitutional and statutory law requires that a fair process be in place to let a property owner challenge a condemnor’s right to acquire private property, including a right to appeal the initial decision. Property acquired by a condemnor must be for public use, and property owners have the right to an immediate and expedited hearing on right-to-take. Two of these requirements will remain in place regardless of statutory revisions: the requirement that property must be needed (i.e., not arbitrary) for public use, and the right to one appeal. Only an amendment(s) to the Kentucky Constitution would alter …

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 …

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.

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 …

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 …

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

Low-Cost Modal Identification Sensors For Bridge Field Testing, Daniel Linzell, Saaed Eftekhar Azam, Samira Ardani, Ahmed E Rageh

Nebraska Department of Transportation: Research Reports

This report provides a framework for experimental load rating of bridges via inclusion of low-cost dynamic sensors and dynamic tests. Currently 25% of the bridges in Nebraska are posted for live load. According to the National Bridge Inventory (NBI) in 2012, 93% of all postings in the US were based analytical load ratings, 7% were posted using field evaluation and engineering judgement, and 1% were posted using experimental load rating methods.

Instrumentation costs and traffic interruptions can be problematic when load testing is necessary to accurately assess in-situ bridge live load capacity. Recent advances in (i) sensing technology and (ii) …

Transportation Sustainability, Eleni Christofa

Sustainability Education Resources

An overview of sustainable transportation planning practices and management strategies and policies; current transportation trends; environmental and energy policies; nonmotorized modes (mainly bicycles and pedestrians); public transportation; life-cycle assessment for transportation infrastructure; alternative fuel vehicles; vehicle emission estimation models; demand management strategies (including parking policies, pricing strategies).