The philosophy, design, and testing of a uniform applied load flat plate testing machine

The presence of a central crack, and its associated plastic zones may significantly affect the distribution of the stress applied by a loading machine, to a test plate. As a result the fracture stress may be affected, usually optimistically. Examples of these effects are discussed. The design of a machine in which the load is uniformly applied to the test specimen is described and preliminary test data presented. Mild steel plate tested at ambient temperature has fractured at less than general yield. (orig.)