Delineation of Linear Roadside Hardware Systems and Roadside Obstacles (2026)
Chapter: 1 Introduction
CHAPTER 1
Introduction
The advancement and implementation of roadside safety hardware on roadways have reduced crash severity when errant vehicles exit roadways. Roadside hardware is evaluated through full-scale crash testing in a controlled environment to determine its crashworthiness. However, delineating roadside hardware and obstacles has not been considered in the crashworthy evaluation of roadside hardware. In addition, limited research and testing have been conducted to evaluate the effect of delineating roadside hardware and obstacles. A few state departments of transportation (DOTs) reported a reduction in crashes and injury severity when enhanced continuous delineation was installed on a roadside hardware system. For example, Utah DOT reported a reduction in motorcycle crashes when a yellow continuous rubrail was added to an existing guardrail (Silvestri et al. 2021). Although this case study was limited, it highlighted the potential for crash reduction when delineation is added to a roadside hardware device. Additional research was needed to investigate and determine whether specific delineation practices can reduce crashes or crash severity.
Objectives
The objectives of this research project were to (1) develop guidelines for delineating linear roadside hardware and obstacles and (2) propose draft language to update relevant documents.
Outline
Part I of this research report is divided into the following remaining chapters:
- Chapter 2: Background and Current Practice, which reviews previous research related to the delineation of roadside hardware and obstacles. In addition, the current state of practice for delineating roadside hardware and roadside obstacles is discussed.
- Chapter 3: Crash Data Analysis and Findings, which outlines the conduct of a crash data analysis to evaluate the effect of two delineation practices.
- Chapter 4: Human Factors Study and Findings, which discusses a two-part study that evaluated several concrete barrier, guardrail, and culvert delineation practices through the collection and analysis of driversʼ reactions to these practices.
- Chapter 5: Conclusions and Suggested Research, which summarizes the research project and provides recommendations for future research.
