This report present a design guide for the determination of where guardrail is required and how it should be installed geometrically to enchance highway safety. The principles of guardrail installation covered here apply for the most part to various forms of guardrail. although the type specifically selected for this study is the universal W-section formed metal sheet, generally referred to as the "beam-type guardrail". These criteria, however, are not intended to serve as a recommendation for the use of beam-type guardrail in preference to some other form. Rather the objective is to furnish a design guide for the installation of one particular type of guardrail- a type which is used predominantly throughout the United States and the performance of which has been researched to a reasonable degree under full-scale vehicle impact test. Similar studies and development of design criteria for other types of guardrail are anticipated in the near future.
Samenvatting