This work deals with the dependence of fracture behaviour on the strain rat
e of a commercial pipeline steel. Low-blow impact tests, using a Charpy pen
dulum setup, and conventional static fracture tests were carried out with t
his material. Experimental results showed that the material fracture toughn
ess increases slightly with strain rate. Numerical analyses of all the expe
riments were also performed, using a micromechanical damage model that expl
ains the influence of the strain rate on the fracture toughness. Particular
attention was paid to the blunting process at the crack tip under dynamic
conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.