Energy absorbing guardrail system having a modified first upper post

A highway crash attenuation system having W-beam rail elements attached to a plurality of vertical posts;

• an impact terminal having a feeder chute for guiding one or more of said W-beam rail elements through said impact terminal;
• and a first anchor cable extending from a first breakaway post anchor to an anchor cable release mechanism releasably attached to at least one of said W-beam rail elements downstream of said first breakaway post anchor, said first breakaway post comprising:
• an upper post section and a lower post section, said upper post section having a first anchor cable through notch in an upstream wall of said upper post section and a second notch in a downstream wall of said upper post section, said anchor cable passing through said first notch in said upstream wall and said second notch in said downstream wall;
• spaced-apart sections of lateral support lips extending along a lower edge of a downstream face of said upper post section, said spaced-apart support lip sections having a space therebetween such that a cable pass through opening in said second notch is unobstructed;
• a cable anchor bearing plate engaged with an upstream face of said upper post section, said bearing plate having a first anchor cable through hole through which said anchor cable is adapted to pass and be retained therein by a locking nut affixed to an upstream most end of said anchor cable, wherein said bearing plate is disposed at a predetermined angle with respect to said first breakaway post by engaging a spacer between a top end of said plate and an upstream face of said upper post;
• and
• an anchor bearing stabilizing bolt extending through a second hole in said bearing plate and secured in a stabilizing hole in said upstream face of said upper post section.