Guidance for the Selection, Use, and Maintenance of Cable Barrier Systems


Book Description

This report provides guidance for the selection, use, and maintenance of cable barrier systems. While cable barrier systems have been in use for more than 70 years, their use has been on the rise and is expected to continue in the future. The increase in use of cable barrier systems has been attributed to the success rate in keeping vehicles from crossing the median, reducing roadway departures, and decreasing impact severity. Due to advancements in cable barrier system technology, installation and repair costs are lower and cable barrier use has increased in varying roadway environments. Safety studies, although limited, have shown that cable barriers help reduce those median cross-over collisions that lead to some of the most severe head-on type crashes. This document will be of particular interest to design, maintenance, traffic, and safety engineering professionals.




Roadside Design Guide


Book Description

This document presents a synthesis of current information and operating practices related to roadside safety and is developed in metric units. The roadside is defined as that area beyond the traveled way (driving lanes) and the shoulder (if any) of the roadway itself. The focus of this guide is on safety treatments that minimize the likelihood of serious injuries when a driver runs off the road. This guide replaces the 1989 AASHTO "Roadside Design Guide."







Guardrail and Median Barrier Crashworthiness


Book Description

This synthesis will be of interest to state department of transportation (DOT) roadway design, traffic, structural, maintenance, and research engineers and others concerned with highway safety issues. This synthesis describes the current state of the practice for the use of guardrails and median barriers and their crashworthiness. It includes information about the crashworthiness and typical applications of the most common, permanently installed, nonproprietary guardrail and median barrier systems used in the United States today. A significant amount of detail is included in the text to aid the design, selection, and locating processes for safe and effective guardrails and median barriers. The report presents data obtained from a review of the literature and a survey of state DOTs. The synthesis presents a description of the typical longitudinal barriers in use today, including drawings, the extent of their use, and the most recent testing on each guardrail and barrier system, with particular emphasis on NCHRP Report 230 and 350 requirements. In addition, it discusses the maintenance issues, cost constraints, and common problems with each type of barrier. The synthesis only discusses the crashworthiness of guardrails and median barriers; their transitions and terminals are not discussed.




Roadside Safety Design


Book Description

This roadside safety design package has been developed to satisfy a need for training in this area. It is hoped that all persons involved in the design, construction, operation, and maintenance of highways will become familiar with the concepts contained in the program. The concepts and practices discussed come from those contained in the AASHTO publication, "Highway Design and Operational Practices Related to Highway Safety". They are discussed in considerable depth in this program and should provide a good working knowledge of roadside safety design. Much of the program is oriented around freeways; however, the principles apply equally toward the lower order highway.




Guidelines for Guardrail Implementation


Book Description

Explores guidance on selecting the appropriate barrier performance level for the installation of longitudinal barriers. The appendices are not published in this report. They are only available online.




Synthesis of Highway Practice


Book Description




Guardrail Performance and Design


Book Description

Barrier installations are warranted (or justified) only at highway locations where the consequence of an errant vehicle leaving the roadway is judged to be more hazardous than the impact with the barrier installation. A six degree-of-freedom mathematical model was found to be useful in describing dynamic behavior of a vehicle during impact. Predictions of vehicle and barrier behavior correlated with results obtained from full-scale crash tests. Crash conditions simulated with a computer were used to identify and evaluate vehicle static and dynamic as well as barrier parameters. Vehicle weight, yaw mass moment of inertia, and deformation constant were found to be significant.







NCHRP Report 537


Book Description