Proposed Revisions to the Current Charpy V-Notch Requirements for Structural Steel Used in U.S. Bridges

Abstract

The purpose of the research presented in this paper is to reexamine the current Charpy V-notch (CVN) requirements for steel bridges in the United States using state-of-the-art applied fracture mechanics analysis. Proposed revisions to the current CVN requirements are introduced. It is shown that, in general, the typical fracture toughness implied by current minimum CVN requirements results in a trend of decreasing resistance to brittle fracture as the minimum specified yield strength grade increases. The results also show that fracture resistance for the current minimum CVN requirements for the three AASHTO temperature zones is inconsistent for different high-performance steel (HPS) grades. A realignment of the current CVN test temperatures and required notch energy is proposed by normalizing all grades to the crack tolerance associated with the AASHTO yield strength grade 36 ksi steel CVN requirements.