The deformation and tearing of thin square plates subjected to impulsive loads - An experimental study

Experimental results for clamped mild steel square plates subjected to impulsive loads are reported. The strain rate-sensitive plates exhibit mode I(large ductile deformation), mode II (tensile-tearing and deformation) and mode III (transverse shear) failure modes. Three phases of mode II are identified as mode II* (partial tearing), mode IIa (complete tearing with increasing mid-point deformation), and mode IIb (complete tearing with decreasing mid-point deformation). For the cases where complete tearing occurs (modes II and III) the velocity of the square disc torn from the base plate is measured. An attempt to measure the speed of rotation of the disc is discussed. Threshold for the onset of failure modes II and III are given. Comparisons between the response of square and circular plates are discussed.