Abstract
When using a classical SHPB (Split Hopkinson Pressure Bar) set-lip, the useful measuring time is limited by the need of separating the waves propagating in opposite directions. A new Method for separating and rebuilding waves in finite bars was developed, with no time limit, from N strain measurements and P particle velocity measurements (N + P greater than or equal to 2). It takes account of the wave dispersion in elastic and viscoelastic bars; The method is illustrated with the loading of a free bar where the measured displacement is 30 times longer than the displacement that would be obtained with the classical method. (C) 2001 Academic des sciences/Editions scientifiques et medicales Elsevier SAS.