Dissipated strain energy method for determining preconsolidation pressure

The dissipated strain energy method (DSEM), a new method for determining the preconsolidation pressure, is presented in this paper. Compared with the energy method, the DSEM uses dissipated strain energy and the slope of the unloading–reloading cycle (in the strain energy – effective consolidation stress space) for the plot to minimize the sample disturbance effects and eliminate the effect of elastic deformation. Dissipated strain energy, in terms of micro mechanics, is directly related to the irreversible process of consolidation and can be supported by theories dealing with consolidation and compaction. The use of the unloading–reloading slope to simulate the elastic reloading for the recompression stage can minimize sample disturbance effects. Examples presented indicate that the proposed new method is less operator dependent than most of the existing methods.Key words: dissipated strain energy, preconsolidation pressure, consolidation, energy method, dissipated strain energy method.