ABSTRACT
The principle of eective stress as proposed by Terzaghi (1936), is one of the most fundamental concepts in soil mechanics. This principle states that when a soil element is subject to a given stress state (described by the three total principal stresses 1, 2 and 3) and when the soil voids are completely lled with water, it is the eective stress state, described by the eective principal stresses 01,
0 3 that governs the soil response. These eective prin-
cipal stresses are calculated as the dierence between the total stresses and the water pressure u, i.e. 01 = 1 u, 02 = 2 u, and 03 = 3 u. A soil's response to a change in the stress state (compression, distortion, and a change of shearing resistance) is then exclusively due to a changes in the eective stresses. To study the response of a granular material to a change in eective stresses using DEM, it is valid to model dry conditions; then the applied total stresses will equal the eective stresses.
