Designing Fail-Safe Structures for Highway Safety

The immensity of the American highway transportation system is presented briefly together with the associated ever increasing annual cost in human lives, injuries, and economic loss. Profitable categories for structural design consideration are delineated. After listing acceptable, tolerable deceleration limits and other design criteria, design examples to achieve greater accident survivability are functionally and numerically described in considerable detail. Examples include large timber sign posts with drilled holes, breakaway sign posts, frangible and slip-base luminaire supports, an overheard sign bridge with breakaway supports, and crushable energy absorption vehicle crash barriers for use at gores and at median bridge piers. The implementation of research results and innovation of effective design techniques to achieve frangible, fail-safe highway structures are encouraged. To those closely associated with the development of the nation's highways, cost benefits are dramatically depicted by research and actual happenstance examples.