BACKGROUND

Historically, the safety performance of roadside safety hardware has been evaluated through full-scale vehicular crash testing, which is notably expensive and time-consuming. Additional physical crash testing may be required to approve roadside safety device modifications. Recently, certain types of finite element analysis (FEA) crash simulations have been tested and used for the approval of design modifications. Many transportation agencies are now considering the acceptance of computer simulation in lieu of full-scale crash tests to approve modifications to roadside safety hardware. The transition to computer simulation has enabled design optimization and substantially reduced the need for expensive and lengthy physical crash tests, thereby decreasing the overall development and installation costs of roadside safety hardware.

NCHRP Web-Only Document 179: Procedures for Verification and Validation of Computer Simulations Used for Roadside Safety Applications (2011) established the first standardized verification and validation (V&V) procedure for roadside safety hardware in the United States. These procedures were developed based on the requirements outlined in the NCHRP Report 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features. However, in 2009, the Manual for Assessing Safety Hardware (MASH) superseded the NCHRP Report 350, emerging as the latest roadside hardware crash testing standard.

While the previous NCHRP document provided unified simulation comparisons for the rigid vertical-faced barrier, research is needed to update the V&V procedures for the broader spectrum of roadside safety hardware according to the categories and test levels specified in MASH. The revised V&V procedure is expected to enable end users, such as state departments of transportation (DOTs), to use computer simulations (e.g., FEA) as a viable alternative to full-scale crash testing for MASH hardware review and approval. In addition, there is a need to standardize the simulation reporting format beyond the V&V process to enable state DOTs to conduct more effective and consistent reviews of crash simulation testing results.

 OBJECTIVE

The objective of this research is to develop guidelines to establish two key elements: (1) a standardized, confidence-level-based procedure for the V&V of computer simulations of roadside safety hardware, applicable across all MASH categories and test levels; and (2) a uniform reporting format for computer simulation inputs and results to facilitate consistent comparison and review.

Accomplishment of the project objective will require at least the following tasks.

STATUS: Work has been initiated. The first interim report is expected in July 2025.