Dynamic Fracture Criteria Evaluation of Bridge Structural Steel

J-integral is the main effective and commonly used tool for elastic-plastic cracked material resistance assessment. Considering ductile behavior of bridges steel integral approach is suitable for fracture toughness evaluation. The paper presents the method of dynamic fracture parameter J-integral evaluation in case of elastic-plastic deformation of bridge structural steel. This experimental technique is based on determination of impact fracture energies and displacements which correspond to these energies at the moment when loading rate reaches max and fracture loads. Theoretical solutions were confirmed by experimental data obtained from Three-Point Bend tests of rectangular cross section specimens with V form notch. Impact loading was generated by impact tester with drop weight. 5 series of specimens with different geometry were tested during experiment. The developed methodology enables to predict the impact fracture toughness of bridge structural elements