Influence of notch on the elastic–plastic response of clamped beams subjected to low velocity impact

In the present paper, experimental and numerical results on deformation and failure of clamped mild steel beams with and without notches subjected to low velocity impact are reported. Three sets of mild steel beams are used in experiments: (i) Beams without notch (ii) beams with 3.0 mm wide rectangular notch and (iii) beams with 0.35 mm wide rectangular notch. The response of the beam is studied in terms of maximum permanent deflection and strain history during contact period. High-speed digital camera was used to capture the impact phenomena of beam specimens. The effect of notch depth, notch width and impact location on the beam response is studied. The presence of notch in beams increases the permanent deflections, and increases the chances of initial tearing failure at the notch location. It is observed from experiments that, the extent of notch influence on dynamic response depends on notch depth and location. In the notched beam, the crack started at the notch corner and extended upwards resulting in failure. The numerical simulations of the experimental impact tests were carried out using the commercial finite element software (ANSYS) and good agreement between numerical and experimental permanent deflection values was observed. The instantaneous distributions of curvature profiles of beam computed numerically are presented for both notched and unnotched beams.