Pilot In-service Performance Evaluation of Guardrail Terminals in Washington State

A pilot routine in-service performance evaluation (ISPE) was undertaken for guardrail terminals following the process outlined in NCHRP 22-33. Controlled stop, rollover, vehicle mix, and secondary impacts on the roadside and roadway were evaluated as performance measures using data sourced from the Crash Location & Analysis System (CLAS) database and the WSDOT Engineering Crash Data Mart for years 2016 through 2020. Four Performance Assessment Levels, ranging from no exclusions of crash data to exclusions of crash data limited to vehicle type and speed limit were assessed. For all five performance measures, the study found no measurable differences between the performance of the major types of guardrail terminal in use on state highways within WSDOT jurisdiction

Pilot In-service Performance Evaluation of Impact Attenuators in Washington State

A pilot routine in-service performance evaluation (ISPE) was undertaken for impact attenuatorsfollowing the process outlined in NCHP 22-33. Controlled stop, rollover, vehicle mix, and secondary impacts on the roadside and roadway were evaluated as performance measures using data sourced from the Crash Location & Analysis System (CLAS) database and the WSDOT Engineering Crash Data Mart for years 2016 through 2020. Four Performance Assessment Levels, ranging from no exclusions of crash data to exclusions of crash data limited to vehicle type and speed limit were assessed. For all five performance measures, the study found no measurable differences between the performance of the major types of impact attenuators in use on state highways within WSDOT jurisdiction

Pilot In-service Performance Evaluation of Cable Barrier in Washington State

A pilot routine in-service performance evaluation (ISPE) was undertaken for cable barrier following the process outlined in NCHRP 22-33. Barrier breach, rollover, vehicle mix, and secondary impacts on the roadside and roadway were evaluated as performance measures using data sourced from the Crash Location & Analysis System (CLAS) database and the WSDOT Engineering Crash Data Mart for years 2016 through 2020. Four Performance Assessment Levels, ranging from no exclusions of crash data to exclusions of crash data limited to vehicle type and speed limit were assessed. For all five performance measures, the study found no measurable difference between the performance of the four major types of cable barrier in use on state highways within WSDOT jurisdiction, including three-strand versus four-strand

DISCOVERY OR AS EVIDENCE AT TRIAL IN ANY ACTION FOR DAMAGES AGAINST WSDOT

The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Washington State Transportation Commission, the Washington State Department of Transportation (WSDOT), or the Federal Highway Administration (FHWA). This report does not constitute a standard, specification, o