Abstract: Based on MohrCoulomb(MC)criterion and plane strain condition， a new DruckerPrager(DP) type criterion under nonassociated flow rule is presented. In the new DP criterion the volumetric plastic strain is introduced and its increment equals to that of the MC criterion. Based on the analysis on π plane， it is found that the proposed DP type criterion is better than the DP criterion compared to the MC circumscribed circle or MC inscribed circle when it is applicable to the conditions for stress Lode angle less than zero. Both theoretical and numerical analysis show that this criterion exactly matches with MohrCoulomb criterion in the predicted slope safety factor， agreeing well with that by Spencer method， and it is more accurate than those from classic DP criteria. Both ultimate load and the slip line field obtained from the proposed criterion in analysis of foundation are in agreement with theoretical solution of Prandtl.

Key words: yield criterion, dilatancy angle, nonassociation flow rule, plastic potential function