Fracture Toughness of Structural Grade Bridge Steels. Part II

摘要

This project was performed to determine how brittle fracture resistances of bridge steels vary with loading rate. Critical stress intensities of four ASTM A36 and A441 steels were measured at 32 F at impact loading rates with instrumented Charpy impact tests and at bridge and slow loading rates with 2-inch compact tension tests performed with a cyclic minor load superimposed on the test load. Methods were developed to estimate the minimum critical stress intensity for ductile fracture, and the impact test values and temperatures required to assure this property.