Properties of high tensile steels in historical railway bridges Available to Purchase

During the routine testing of structural steels in bridges in western Poland, on two segments of railway lines built back in 1875, it was revealed that four bridge structures had been manufactured from steels of higher tensile strength than regular mild steel. These bridges had been constructed as three-span structures, simply supported and continuous. They had been built during the reconstructions to meet heavier railroad loadings introduced in the 1920s. For each structure, chemical composition, strength, hardness and notch toughness were tested. In the first two bridges, medium-carbon steel was detected. In the other two bridges, silicon steel was found to have been used. The ultimate strengths of these steels were higher than 500 MPa. The strength test results were surprising, as there are only a few reports of using such steels in early railway bridges. The mechanical properties of the steels were tested under naturally aged and normalised conditions, allowing the assessment of ageing effects.