Page 199 - T. Anderson-Fracture Mechanics - Fundamentals and Applns.-CRC (2005)

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Dynamic and Time-Dependent Fracture 179

FIGURE 4.5 Effect of loading rate on the cleavage fracture toughness of a structural steel. Taken from Barsom,
J.M., “Development of the AASHTO Fracture Toughness Requirements for Bridge Steels.” Engineering
Fracture Mechanics, Vol. 7, 1975, pp. 605–618.

energy. Arrest occurs below the resistance curve, after most of the available energy has been dissipated.
The apparent arrest toughness K is less than the true material resistance K . The difference between
IA
Ia
K and K is governed by the kinetic energy created during crack propagation; K is a material
Ia
IA
IA
property, but K depends on geometry.
Ia

FIGURE 4.6 Effect of loading rate on the J-R curve behavior of HY80 steel. Taken from Joyce, J.A. and Hacket,
E.M., “Dynamic J-R Curve Testing of a High Strength Steel Using the Multispecimen and Key Curve Techniques.”
ASTM STP 905, American Society for Testing and Materials, Philadelphia, PA, 1984, pp. 741–774.