Value of Charpy impact test results with sub- and half-size specimens extracted from overage steel bridge members

For the maintenance of steel bridges, the mechanical properties of steel used in the bridges must be elucidated. When enough dimensions of specimens cannot be extracted from the actual members, miniaturized specimens are used for evaluation. In the case of the Charpy impact test, sub- and half-size specimens are specified instead of full-size specimens of which the thickness is 10 mm. The value of absorbed energy and energy transient temperature obtained by Charpy impact tests with sub-size and half-size specimens were investigated from the viewpoint of maintenance of bridges in this study. The absorbed energy was not in proportion to the thickness of specimens of steel used in the actual overage bridges. The tendency of energy transient temperature obtained by thin specimens of the overage steel differed from that of the present steel. A method for evaluating the performance against brittle fracture occurrence based on the WES3003 criterion was examined. The results show the significance of evaluation based on the energy transient temperature for reasonable maintenance of bridges.