Estimation of intergrity of cast-iron cask against impact due to free drop test, (3)

As a cask material, ductile cast iron has the potential to fail in a brittle manner under certain temperature and load conditions. The design criterion of ductile cast iron casks against brittle failure due to a drop test, has been proposed by CRIEPI. In this report, in order to verify the proposed design criterion, a 9m drop test using a full scale cask with an artificial flaw of 83.5mm in depth located at the most critical location was carried out at the low temperature of -40degC. As the test results, no crack propagation from the artificial flaw was observed under the severe condition such that the safety factor (1.78) calculated from the design criterion was below the value (2) in the criterion, thus confirming that the proposed brittle failure design criterion is applicable to evaluate the integrity of ductile cast iron cask against brittle failure due to a drop test. (author)