Transportation Engineering Commons^™

Evidence From Urban Roads Without Bicycle Lanes On The Impact Of Bicycle Traffic On Passenger Car Travel Speeds, Jaclyn S. Schaefer, Miguel A. Figliozzi, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

A concern raised by some motorists in relation to the presence of bicycles on urban roads without bicycle lanes, discussed in part of the traffic literature, is that cyclists will slow down motorized vehicles and therefore create congestion. This research answers this question: do bicycles reduce passenger car travel speeds on urban roads without bicycle lanes? To answer this question, a detailed comparative analysis of the travel speeds of passenger car (class two vehicles) on lower volume urban roads without bicycle lanes is presented. Speed distributions, the mean, and the 50th and 85th percentile speeds for two scenarios were examined: …

User-Rated Comfort And Preference Of Separated Bike Lane Intersection Designs, Christopher Monsere, Nathan Mcneil, Rebecca Sanders

Civil and Environmental Engineering Faculty Publications and Presentations

Improved bicycle infrastructure has become increasingly common in the United States as cities seek to attract new riders, including the demographic who do not feel comfortable riding with motor vehicle traffic. A key tool in designing low-stress networks is the use of separated or protected bicycle lanes, and intersections are the critical links. This paper presents an analysis of the perceived level of comfort of current and potential bicyclists from 277 survey respondents who rated 26 first-person video clips of a bicyclist riding through mixing zones, lateral shifts, bend-in, bend-out, and protected intersection designs. A total of 7,166 ratings were …

Full-Depth Reclamation Of Asphaltic Concrete Pavements, Tony L. Beckham, Brad W. Rister, Charlie Sun

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) has used a full-depth reclamation (FDR) process over the past few years to rehabilitate asphalt pavements exhibiting widespread base failures. FDR transforms existing hot-mix asphalt (HMA) pavement and underlying granular materials into a stabilized base layer. The stabilized layer is then overlaid with a new pavement surface layer. Until now, deciding when and how to use the FDR process has not been well specified in Kentucky — the Cabinet has commonly used a Special Note for Cement Stabilized Roadbed as guidance and relied on the contractor for acceptable materials design. Previous research conducted by the …

Potential Effect Of Cable Median Barriers On Commercial Vehicle Crossover Crashes, Nikiforos Stamatiadis, Shraddha Sagar, Samantha Wright, Eric R. Green, Reginald R. Souleyrette, Michael A. Fields, Teng Alex Wang

Kentucky Transportation Center Research Report

In 2016, commercial motor vehicles (CMVs) were involved in 4,079 fatal crashes in the U.S., representing 11.8 percent of all fatal crashes. State of Kentucky crash data for 2015-2016 show that per capita crash rates and increases in crash-related fatalities exceeded the national average. Crossover crashes occur when a vehicle leaves its intended path and veers into the path of oncoming traffic, typically resulting in head-on or sideswipe opposite direction crashes. Cable median barriers are a countermeasure which can potentially be used to mitigate crossover crashes. This research investigated the potential effectiveness of cable median barriers on CMV crashes. Analysis …

Evaluation Of Alternative Rumble Strip Designs, William Nicholas Staats, Kenneth R. Agent, Brian K. Howell

Kentucky Transportation Center Research Report

Since Kentucky’s initial rumble strip designs were adopted, there has been additional research and experimentation in other states with alternative designs as a response to complaints from the public about noise pollution caused by rumble strips. The new research indicates that other rumble strip designs might provide increased interior noise/vibration with decreased exterior noise. Application of these alternative designs in Kentucky could result in improved rumble performance, reduced damage to new pavement, decreased noise pollution, installation on roadways with lower speed limits, and allow reinstallation of rumbles on thin overlays/microsurfacing.

The research team reviewed national and state guidelines for conventional …

Traffic Incident Management Dashboard, Xu Zhang, Reginald R. Souleyrette, Alex Wang, Paul Ross, Eric R. Green, Mei Chen

Kentucky Transportation Center Research Report

Traffic incidents remain all-too-common events on Kentucky’s roadways. They negatively impact the safety of the traveling public and emergency responders and cause significant traffic delays. Congestion associated with incidents can instigate secondary crashes, exacerbating safety risks and economic costs. Traffic incident management (TIM) provides an effective approach for managing highway incidents and reducing their occurrence and impacts. This report discusses the establishment of and methods of calculation for five TIM performance measures that can be used by the Kentucky Transportation Cabinet (KYTC) to improve incident response. The measures are: Roadway Clearance Time, Incident Clearance Time, Secondary Crashes, First Responder Vehicle …

Kytc Maintenance Field Operations Guide Supplement, Bryan Gibson, Candice Y. Wallace, Nancy Albright, Christopher W. Van Dyke, Steven Douglas Kreis

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) is tasked with managing an asset portfolio that includes over 27,500 miles of roadway and 9,000 bridges. Keeping these assets in sound condition demands significant effort from KYTC’s Division of Maintenance, which includes activities ranging from mowing and litter pickup to cleaning out culverts and performing emergency roadway work. Despite the immense responsibilities shouldered by Maintenance personnel, until this project the Cabinet’s 12 districts lacked a systematic method for capturing and recording maintenance activities. Through a series of workshops held in each KYTC’s district with Section Engineer and Maintenance Supervisors, researchers at the Kentucky Transportation …

Crash Modification Factor Recommendation List, Reginald R. Souleyrette, Riana Tanzen, Eric R. Green, William Nicholas Staats, Federico Valentin Lause Iii

Kentucky Transportation Center Research Report

Practitioners use Crash Modification Factors/Functions (CMFs) to calculate the number of crashes expected once a countermeasure has been implemented. When evaluating design alternatives, CMFs can be used in conjunction with safety performance functions (SPFs) to derive crash predictions. The Federal Highway Administration (FHWA) maintains the CMF Clearinghouse as a repository for CMFs. Contributions are submitted by researchers across the U.S., Canada, and throughout the world. Typically, multiple CMFs are associated with a single countermeasure. Some CMFs only apply to specific facility or crash types. Furthermore, CMF quality varies, and some only apply to specific facility and/or crash types, regions, or …

Research On School Zone Safety, Aemal Khattak, Yashu Kang

Nebraska Department of Transportation: Research Reports

This research investigated different aspects of school zone safety including the effects of speed differentials on drivers’ speeds in active school zones, the effects of school and surrounding characteristics on drivers’ speeds in active school zones, and the safety benefits and costs associated with active school zones. The research team identified 18 schools in Nebraska for data collection that consisted of drivers’ speed data, school and surrounding characteristics, and 2014-2018 reported crash data. The 18 schools were categorized by the school zone speed limit differentials: 35 to 25 mph, 40 to 25 mph, 30 to 25 mph, and 35 to …

Southern California Regional Transit Training Consortium: Skills Gap & Needs Assessment, Tyler Reeb, Benjamin Olson

Mineta Transportation Institute

The transit sector grows and evolves quickly with the needs of growing, busy cities. With this growth comes a need for more transit workers and more training to ensure workers can best serve their diverse communities. This report contains a transit training needs assessment and gap analysis to identify the most pressing challenges of the evolving transit workforce served by the Southern California Regional Transit Training Consortium (SCRTTC). Most importantly, this report documents and determines SCRTTC priorities to ensure the incumbent and future transit workforce is equipped with the professional and technological skills required to address the transformational trends affecting …

Effective Communication Message Strategy For Enhancing Traffic Safety In Fresno County: The Role Of Time Horizon, Regulatory Focus, And Perceived Personal Control, Samer Sarofim

Mineta Transportation Institute

This research empirically investigated the differential effect of message framing on message recipients’ attitudes and intended behaviors related to pedestrian, cyclist, and motorist traffic safety practices. The framework empirically investigated time horizon (expansive vs. limited) and regulatory focus (prevention vs. promotion) message framing.

The time horizon in the message can make someone either think of the future (expansive) or the present (limited). For example, an expansive time horizon message communicates that life is long and directs the focus on the future. On the contrary, a limited time horizon message communicates that life is short and directs the focus on the …

A Multi-Objective Optimization Model To Minimize The Gap In Accessibility To Multi-Use Paths While Maximizing The Economic Efficiency Of Active Transportation Investments For Fresno, California, Chih-Hao Wang

Mineta Transportation Institute

This research examines the accessibility to multi-use paths in a variety of neighborhoods in Fresno, California. This study aims to develop a multi-objective optimization modeling framework to be used by decision makers in transportation and policy to maximize the total accessibility to multi-use paths across the city while minimizing the gap between low- and high- accessibility neighborhoods by an optimal allocation of active transportation. Researchers calculate accessibility to multi-use paths by measuring the total length of multi-use paths (walkway and bikeway) a resident could reach from their own Census block group with a 30-minute cycling ride. The study employs a …

The Fresno State Transportation Challenge, Christian Wandeler, Steven Hart

Mineta Transportation Institute

The goal of the “Fresno State Transportation Challenge” was outreach to schools and community engagement, to provide K-8 students opportunities to learn about transportation and transportation-related careers, and to practice 21st century skills by solving a transportation-related issue in their community. Through the pedagogical frameworks of action civics and eduScrum (a method to facilitate self-managed teamwork with a visual board), teachers and students worked on solving issues in their community. They learned design thinking to identify issues and develop solutions while using eduScrum to manage their work. University students from transportation engineering visited the schools regularly to support the K-8 …

Assessing Complete Street Strategies Using Microscopic Traffic Simulation Models, Bernice Liu, Alireza Shams, Jonathan Howard, Serena Alexander, Alex Hughes, Anurag Pande

Mineta Transportation Institute

Authors of this research developed a traffic simulation model for the downtown San Jose network and evaluated five different street redesign and travel demand combinations. This model aids understanding of network-wide effects of changes in street design for local and regional agencies who are interested in implementing complete streets and/or one-way to two-way conversion. The base network may be altered to model and evaluate other complete streets (e.g., road diet) and tactical urbanism (e.g., farmer’s market on city streets on certain days of the week) scenarios. The 3-dimensional animated videos for each scenario are also created to be used for …

Suitability Of Fusing Vehicle Probe Data And Vessel Data To Contextualize The Multimodal Interaction Impacts On Corridor Mobility – A New Orleans Case Study, Kirk Zeringue

LSU New Orleans Theses and Dissertations

Using New Orleans as a case study, this thesis explores the conflation of vehicle probe data with various vessel datasets to characterize the interactions between container vessels and motor vehicles as it relates to interstate congestion in a port city. The case study investigates the impact of container vessel presence/size, fluctuations in container volumes, and container on barge services on roadway congestion. The exploration relies on comparing different conditions using cumulative distribution functions and the Innovative Trend Analysis. The results showed that fusing vehicle and vessel data is achievable and appropriate, but temporal and data completeness issues can effect results. …

About Computer Simulation Of The Structure Of Cellular Concrete With A Tasked Heat Conductivity, Anvar Ishanovich Adilkhodjayev, S.S. Shaumarov, E.V. Shchipacheva

Journal of Tashkent Institute of Railway Engineers

This article presents the developed mathematical model of the structure of cellular concrete and its computer implementation in the form of a computational software package that allows you to determine pore sizes and characteristics of inter-pore walls, corresponding to the required thermal conductivity of the material. The stages of computer simulation of the macrostructure of cellular concrete are also given.

Calculation Of Hanging Shells Complex Geometry, Sayidmahsud Razzakov, Gennady Fridman, Rasul Khuzhakulov

Journal of Tashkent Institute of Railway Engineers

A method for calculating large-span, spatial hanging shells is presented. A resolving system of equations is obtained for determining the stress-strain state of the hanging shells, the support contour, bearing and stabilizing cables

Plastometry Application For Control Of Portland Cement Consumer Properties, Aleksandr Petrovich Nikolaev, Elena Vladimirovna Kondrashchenko, Valery Іvanovich Kondrashchenko

Journal of Tashkent Institute of Railway Engineers

It was shown that cements of the same strength grade substantially differ at initial dynamics of their interaction with water and structure-forming capacity din the course of stiffening. The necessity was substantiated for current control of Portland cement consumer properties in operation with cement from the same vendor. It was proved that the amount of added plasticizer for obtaining plastisized concrete on the basis of cements of the same strength grade from different vendors may differ several times. The efficiency was demonstrated of input control of Portland cement structure- forming capacity at plants manufacturing concrete and ferroconcrete products, using modified …

Effectiveness Of Seismic Base Isolation In Reinforced Concrete Multi-Storey Buildings, Ravshanbek Abdujabborovich Mavlonov, Sohiba Ergashboevna Numanova

Journal of Tashkent Institute of Railway Engineers

The dynamic reaction of a building to earthquake ground motion is the most critical reason for earthquake actuated damage to structures. The basic concept in seismic isolation is to protect the structure from the damaging effects of an earthquake by introducing a flexible support isolating the building from the shaking ground. Seismic isolation consists of essentially the installation of mechanisms such as isolators which decouple the structure from base. In the present study, the seismic response of the reinforced concrete building, base isolated by lead rubber bearings (LRBs) is compared with the seismic response of the same structure which does …

Method Of Calendar Planning Of Construction Of The Complex At The Early Stage Of Design, M Mirakhmedov, M. Rasulmukhamedov, L.S. Yusupova

Journal of Tashkent Institute of Railway Engineers

The construction schedule developed in the construction organization project does not meet the requirements of the reserve for construction, is not based on the choice of construction and technological schemes and the method of construction organization, therefore, it is not sufficiently reliable, the evidence base stored in the project archive is not confirmed by calculations and Therefore, it cannot be subjected to reliable examination. To eliminate this drawback, a technique is proposed that takes into account the lack of information. The methodology is based on the graphanalytic model of the flow organization of the construction of the complex, which allows …