Bridge Rail and Approach Railing for Low-volume Roads in Iowa


Book Description

Guidelines for bridge rail and approach guardrails can help improve the safety benefits of these devices while minimzing [i.e., minimizing] costs.




Roadside Design Guide


Book Description

"The Roadside Design Guide presents a synthesis of current information and operating practices related to roadside safety and is written in dual units-metric and U.S. Customary. This book is a guide. It is not a standard, nor is it a design policy. It is intended to use as a resource document from which individual highway agencies can develop standards and policies. Although much of the material in the guide can be considered universal in its application, several recommendations are subjective in nature and may need modification to fit local conditions. However, it is important that significant deviations from the guide be based on operational experience and objective analysis. The 2011 edition of the AASHTO Roadside Design Guide has been updated to include hardware that has met the evaluation criteria contained in the National Cooperative Highway Research Program (NCHRP) Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features and begins to detail the most current evaluation criteria contained under the Manual for Assessing Safety Hardware, 2009 (MASH). For the most part, roadside hardware tested and accepted under older guidelines that are no longer applicable has not been excluded in this edition." -- AASHTO website.




Development of Guardrail to Bridge Rail Transition


Book Description

This report describes the development and testing of a guardfence-to-rigid bridge rail transition. The transition consists of a tubular W-beam supported on 7 inch diameter round wood posts. It is designed to transition to a vertical wall or to the concrete safety shaped barrier. It can be used on new construction or as a retrofit for existing installations. Based on a full-scale vehicular crash test program, the design was judged to be in compliance with recommended impact performance criteria as presented in NCHRP Report 230. Also described is a tentative design for approach guardfence at bridge ends near an abutting roadway. The design consists of short radius, curved guardrail supported on weakened round wood posts.
















Public Roads


Book Description