The objective of this study was to report the results of the monitoring of the performance of the ET2000 guardrail end treatment in traffic crashes. This end treatment has an energy absorbing design in which a vehicle will push a guardrail extruder back as posts designed to breakaway are broken. The W-beam guardrail is flattened as it goes through the extruder and exits a slot away from traffic.

Data for a total of 135 collisions involving the ET 2000 were identified. A crash report was obtained in the majority of crashes and the damaged guardrail was inspected in almost all cases. The involved vehicle was inspected when available. Proper or improper performance of end treatments in the collisions were judged, when a police report was available, based on whether it performed as designed.

Field performance of the ET2000, as documented in traffic crashes, shows that, considering all the impacts, this end treatment has performed properly. In some instances the end treatment bent, rather than being pushed straight back, during the collision. This could typically be related to the angle at which the impact occurred.

Results warrant continued use of this type of end treatment. However, its cost compared to other end treatments would not justify a widespread use on all types of highways.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky nor of the Kentucky Transportation Cabinet. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names is for identification purposes only and is not to be considered an endorsement.