Patent ID: 7694941
Filing Date: 2010-04-13
Classification: E01F

Abstract:
1. An end treatment of a guardrail safety system comprising: a terminal portion of a guardrail beam comprising a W-beam having a downstream end and an upstream end, the W-beam sloping from a first vertical height appropriate for redirecting an errant vehicle to a second vertical height proximate the surface of the ground at the upstream end of the W-beam, wherein the upstream end of the W-beam comprises a vertically flattened W-beam that is secured to a terminal support post proximate the surface of the ground; a flattening portion forming a channel through which the terminal portion of the guardrail beam is disposed, a vertical dimension of the channel being greater at a downstream end of the flattening portion than at an upstream end of the flattening portion; and an impact plate coupled to the flattening portion, the impact plate for engaging an impacting vehicle at an end of said guardrail beam; and wherein the upstream end of the W-beam is vertically flattened in an assembled state and prior to an end-on impact, and wherein the impact plate and the flattening portion are advanced longitudinally along the guardrail in a downstream direction by a vehicle during the end-on impact, the advancement of the impact plate and flattening portion dissipating energy to decelerate the impacting vehicle and flattening the guardrail vertically as downstream portions of the guardrail beam are forced into the flattening portion.