Safety Impacts of Fluorescent Yellow-Green Signs on Pedestrians

The Manual on Uniform Traffic Control Devices (MUTCD) specifies the use of yellow sheeting for pedestrian or bicycle signs and fluorescent yellow-green (FYG) for school signs, with an option for the use of FYG sheeting for pedestrian or bicycle warning signs. However, switching from yellow or fluorescent yellow (FY) to FYG for pedestrian and bicyclist signage could involve significant cost and effort for government agencies. The objective of this research study is to synthesize existing research and review the state of the practice regarding the use of FYG for pedestrian and bicyclist signs. The research methodology to meet these objectives includes a literature review, survey of departments of transportation (DOTs) and metropolitan planning organizations (MPOs), and follow up interviews with a subset of DOTs and MPOs. Findings from the literature review indicate that the results from previous research studies are inconclusive regarding the safety benefits of FYG (compared to yellow or FY) for pedestrian and bicyclist signs, and the research may be outdated. There is a wide range of agency practices for FYG signs for pedestrians and bicyclists among responding DOTs and MPOs, but many agencies allow FYG for pedestrians and bicyclists to some extent. Responding agencies have primarily switched to FYG for pedestrian and bicyclist signs based on a belief that the color stands out better and as part of other safety initiatives. None of the agencies that responded to the surveys indicated that they have performed any research studies to evaluate the safety performance of FYG signs for pedestrians and bicyclists. While a limited number of responding have seen improved safety performance (e.g., increased yielding compliance) with the use of FYG, the research did not identify significant and conclusive evidence regarding potential safety benefits associated with the use of FYG for pedestrian and bicyclist signs. Overall, the research findings suggest a need for additional research into the potential safety benefits of FYG signs for bicyclists and pedestrians.

VIEW FINAL REPORT

Report number: cmr 24-019
Published: October 2024

Project number: TR202416

Authors: Henry Brown, Praveen Edara, Carlos Sun, Daeyeol Chang, Zhu Qing, Priscilla Tobias, Jerrid Dinnen, Melissa Jiang

Performing organization: Missouri Center for Transportation Innovation, University of Missouri-Columbia

The Effect of Rubber Fills on the Performance of Infrastructure

One of the most environmentally friendly methods to recycle scrap tires is by shredding them into tire derived aggregate (TDA). TDA possesses desirable properties for various civil engineering applications and has been successfully used as fill material in numerous projects. To address the limitations of previous studies, 27 direct shear tests were conducted using a large-scale direct shear box (3 feet wide, 3 feet long, and 2 feet deep) on different TDA types mixed with soil. Additionally, 9 large-scale compressibility tests were conducted on the soil-TDA mixtures. TDA content was varied from 0 to 100% by weight in the soil mixtures. The direct shear tests were performed under confining pressures of 3.63, 7.25, and 10.88 psi. The results indicated that adding TDA to the soil significantly reduces the dry unit weight of the mixtures. When 25% TDA (Type A or Type B) was added to the soil, it provided the same shear resistance for the soil alone at all considered confining pressures. The compressibility test results showed that the inclusion of TDA increased the compressibility of the mixtures. It was observed that adding TDA to the soil contributed to a strain-hardening behavior in the mixtures. Also, adding 25% TDA reduced lateral earth pressure by 20% on average.

VIEW FINAL REPORT

Report number: cmr 24-018
Published: October 2024

Project number: TR202013

Authors: Mohamed Elashram, Ahmed Gheni, Mohamed ElGawady

Performing organization: Missouri University of Science & Technology

First and Last Mile Connectivity for Missourians

By closing gaps in transit systems or by complementing transportation services, first-last mile transportation services are integral in enabling access to employment opportunities as well as other key destinations. This research study examined first-last mile service programs across the United States and assessed existing conditions in Missouri to learn about the challenges and opportunities in providing first-last mile options supporting access to employment. This study showed that first-last mile services can address gaps in transportation systems, that different modes of transportation offer first-last mile service options to match local contexts and needs, and that partnerships between public agencies, mobility providers and local employers are key to develop first-last mile services supporting access to employment. 

To inform how first-last mile services can support Missourians’ access to employment, the team conducted a scan of over 50 first-last mile services across the United States, produced 15 case studies, and conducted 5 in-depth interviews with mobility providers. To understand what current conditions are affecting first-last mile issues in Missouri, the team developed an existing conditions analysis mapping transit and mobility services in Missouri, conducted in-depth interviews with 2 local transit agencies, and hosted a virtual forum with Missouri’s transportation stakeholders. The team summarized the findings from these research activities and presented recommendations to inform how State departments of transportation, local governments, and transit agencies can support first-last mile services for Missourians.

VIEW FINAL REPORT

Report number: cmr 24-017
Published: October 2024

Project number: TR202109

Authors: Alvaro Villagran, Peter Lauer, Hani Shamat, Luba Guzei, Nicky Althoff

Performing organization: Shared-Use Mobility Center