Highway Rail Crossing Prioritization

Research team members at the University of Kentucky in the Department of Civil Engineering and the Kentucky Transportation Center (KTC) worked with the Kentucky Transportation Cabinet (KYTC) to develop a high-level mechanism for ranking highway-rail crossings for reconstruction and/or rehabilitation. The Highway Rail Crossing Prioritization implementation study yielded the Rail Crossing Improvement Priority (RCIP), which combined qualitative measures of crossing conditions with quantitative measures including proposed project costs and a valuation of the crossing based on rail and truck traffic. This effort provides a template by which further development can yield prioritization procedures for road-rail grade separation projects

Incorporating Crash Severity and Continuous Improvement of SHIFT

The Strategic Highway Investment Formula for Tomorrow (SHIFT) is the Kentucky Transportation Cabinet\u27s data-informed approach for comparing capital improvement projects and prioritizing limited transportation funds. SHIFT 2022 incorporates advancements in methods and flexibility. This project revises the SHIFT crash data safety metric. The crash data safety metric from the previous version of SHIFT was excess expected crashes (EECs). It is computed using the total number of crashes of all severities. Locations with a higher proportion of severe (fatal and injury) crashes received the same weight as locations with an equal number of property damage only crashes. This project redefines the SHIFT crash data safety metric, increasing the weight of serious (KAB) crashes while still accounting for the potential to reduce less serious crashes. It also attends to the five-year and ultimate goals of Kentucky’s Strategic Highway Safety Plan by developing a metric sensitive to these policy goals. The five-year goal is represented by a new definition of EEC (the difference between expected crashes, the Empirical Bayes estimate, and the number of systemwide crashes when the goal is achieved). The ultimate goal is represented by the potential to reduce crashes on all road sections to zero, which is the EB estimate itself

2023 Final Report for Databases in the 2022 Traffic Records Improvement Plan: Facilitating the Development of Projects to Attain the Goals in the Implementation Plan for the 2022-26 Traffic Records Strategic Plan

During fiscal year 2023, with financial support (Grant #M3Da-2022-04) from the Kentucky Office of Highway Safety, the Kentucky Transportation Center (KTC)-continued its work with traffic database officials to facilitate successful attainment of the remaining goals from the 2017-21 Traffic Records Strategic Plan (TRSP), which goals are in the 2022-26 TRSP Transportation Records Improvement Plan (TRIP). For most databases, some new goals were developed; this required further refinement of some projects or strategies to improve database performance. Projects to complete the goals in the TRIP were continued and some completed for the following databases: CRASH, Citation/Adjudication, Injury Surveillance (KIPRC and EMS), Vehicle Registration, Roadway, and Driver Licensing

Two-Geometry Roundabouts: Design Principles

Although concentric multi-lane roundabouts have a higher capacity than single-lane roundabouts, they have the disadvantage of a higher driving speed through the roundabout. They also reintroduce the possibility of lane changing on the roundabout and hence raise the risk of accidents. The authors developed and studied the two-geometry roundabout in an attempt to deal with these and other drawbacks. This type of roundabout has the following features: no lane changing (or at least as little as possible) on the roundabout; lower driving speed through the roundabout; advantages in the manoeuvers of heavy-duty vehicles. This paper discusses the concept of the two-geometry roundabout and the details determining success. In detail: first of all, the characteristics of the single-lane and multi-lane roundabouts will be illustrated, focusing on the problems of the latter; after which the development, the main characteristics and the typologies of the two-geometry roundabout will be illustrated (with some examples attached); finally, we will focus on the positive effects of the two-geometry roundabout on heavy vehicles. In the final part, the methods for calculating the capacity of the two-geometry roundabout will also be introduced, and therefore the conclusions of the paper. The paper discusses the concept of the Two-Geometry Roundabout and outlines its principal advantages. We first develop, the main characteristics and typologies of Two-Geometry Roundabouts illustrated (with some examples attached); therefore, we focus on the positive effects of the Two-Geometry Roundabout with particular attention on heavy vehicles. Finally, we present methods for calculating the capacity of the Two-Geometry Roundabout and conclude the paper

Upgrading Traffic Circles to Modern Roundabouts to Improve Safety and Efficiency – Case Studies from Italy

This paper presents a procedure for analysing safety and operational improvements made possible by converting traffic circles to modern roundabouts. An Italian case study is presented for alternative layouts under various traffic demand scenarios. In the application of the procedure, the average waiting times and queue lengths at entries are computed with an analytical capacity model, using default values for gap parameters. Then, the roundabout is dynamically simulated. The simulation results in a revised set of gap parameters that are in turn used as inputs to a second trial of the capacity model, and in turn fed back into the simulation. The two steps are repeated until the parameters reach a pre-selected convergence criterion, so that gap parameter values for both the static capacity and dynamic microsimulation models are in equilibrium. Therefore, the applied procedure can conduct both static and dynamic roundabout design, usually applied separately. One can start with default values in guidelines and couple them with limited field data, improving both the expected results and cost-effectiveness of solutions. Next, safety is estimated using dynamic simulation software and a compatible conflict counting model to acquire surrogate measures of safety. Level-of-serviceand surrogate safety indicators for the existing and redesigned roundabouts are then compared. The procedure is first demonstrated on an old “ultra-large” roundabout. The procedure is tested on this roundabout using the Highway Capacity Manual 2016 (HCM2016), AimsunTM, and Surrogate Safety Assessment Model (SSAM) software. A redesign is shown to be far superior in efficiency and safety. Finally, two cases are described where large first generation roundaboutswere upgraded to modern standards.</p

Pedestrian and Bicycle Improvement Scoring Method for SHIFT–2024

State transportation agencies have limited funding to deliver multimodal transportation programs that address the needs of all users. To allocate project funding in an impartial and objective manner, many agencies have adopted data-driven scoring systems that are used to evaluate the merits of proposed capital improvement projects. The Kentucky Transportation Cabinet introduced the Strategic Highway Investment Formula for Tomorrow (SHIFT) for this purpose. Until now SHIFT, has evaluated projects based five core variables — congestion, safety, benefit-cost ratio, asset management, economic growth. To address local needs, SHIFT has also allocated points that Area Development Districts, metropolitan planning organizations, and Cabinet districts can use to boost scores, and thus increase their chances for funding. However, SHIFT has not explicitly addressed pedestrian/bicycle improvements in its scoring formula. Based on a literature review and experimentation with different methodologies, this report proposes a method of scoring proposed pedestrian and bicycle improvements for SHIFT—2024. Under the scoring system, up to 10% of SHIFT’s available points may be awarded to pedestrian and bicycle improvements — 5% for pedestrian improvements and 5% for bicycle improvements. In addition to the new scoring component, the report proposes a list of general project categories that can be used to classify pedestrian/bicycle improvements. Categorization can facilitate benefit-cost analysis, establish a foundation for systematically evaluating projects, and inform the future refinement of the SHIFT process

Incorporating Variability in KYTC Planning and Project Development

Transportation planning and design decisions are typically made using point estimates of traffic and safety measures. This report addresses the uncertainty of data used to make these decisions. It focuses on two data elements — project safety ratings and volume estimates from traffic counts. For safety ratings, the Kentucky Transportation Cabinet’s Strategic Highway Investment Formula for Tomorrow (SHIFT) crash history score is used as a case study. Confidence intervals are developed for the Cabinet’s new safety metric, which incorporates estimates of future crashes by severity as well as excess expected crashes above safety goals. For traffic counts, the report develops confidence intervals based on daily and monthly expansion factors across multiple permanent count recording stations. Results should help users of these data better understand the range of data the point estimates represent and the likelihood that projects based on these plans and designs will function as expected

Quantifying Roadside Assessment for Highway Safety

Many of Kentucky’s two-lane rural roads pose an above average risk for fixed object crashes. In Kentucky, run-off-road (ROR) collisions with fixed objects account for 18.9% of all crashes and 41.6% of fatal crashes. Accordingly, ROR crashes are a significant public safety hazard that must be addressed through judicious investments in safety improvements. Until recently, transportation engineers and planners have mostly leveraged qualitative metrics to prioritize safety investments, however, qualitative methodologies are problematic because they may rely excessively on subjective opinion and intuition. This study applied methodologies and software from the U.S. Road Assessment Program (usRAP) to develop quantitative, objective roadside safety ratings for rural two-lane roads in the state of Kentucky on which 20 or more crashes occurred from 2010 to 2015. Kentucky Transportation Center researchers generated usRAP star rating scores following standard protocols and, to validate the methodology, compared those scores to the number of ROR collisions over the specified interval. Analysis revealed robust correlations between star rating scores (and star ratings) and crash data, justifying their as an objective measure of roadside safety. Researchers also delivered a comprehensive database containing over 126,000 records to the Kentucky Transportation Cabinet, which can be used to examine roadside severity and potentially inform future highway investments

Improving Sustainable Mobility through Modal Rewarding: The GOOD_GO Smart Platform

Private car mobility registers today a h igh accident rate and around 70% of the overall CO2 emissions from transport were generated by road mode split (European Commission, 2016). Moreover, in urban areas they occur 38% of the overall fatalities from road transport, and 23% of the overall CO2 emissions (European Commission, 2013). As a result, a modal shift of at least a part of passenger transport in urban areas, from private car to sustainable transport systems is desirable. This research aims to promote sustainable mobility through two mutually reinforcing "main actions": firstly, there is a r ewarding Open-Source platform, named as GOOD_GO; secondly, there is the SW/HW system connecting to the wide world of private and/or shared bicycles. Through the GOOD_GO platform Web portal and App, a user enters a so called 'social rewarding game' thought to incentive sustainable mobility habits, and gets access to the second item consisting of a system to disincentive bike-theft and based on the passive RFID technology. The low-cost deterrent bike-theft and bike monitoring/tracking system is functional to bring a big number of citizens inside the rewarding game. In 2018, a pilot test has implemented in the city of Livorno (Tuscany, It), and it involved around 1,000 citizens. Results were quite encouraging and today, the cities of Livorno, Pisa and Bolzano will enlarge the incentive system both to home-to-school and home-to-work mobility. The Good_Go platform is an actual M-a-a-S (Mobility-as-a-Service) application, and it becoming a Mobility Management decision system support, jointly with the opportunity of organizing more incentive tenders and rewarding systems types