一个新的D-P类准则及其应用

基于Mohr Coulomb(M-C)准则及平面应变条件，建立了非关联流动法则的D-P准则.该准则引入了塑性体积应变，所求的塑性体积应变增量和M-C准则相等，在π平面上，当应力罗德角小于零时，建议的D-P准则与以往的外角外接圆及内切圆相比，能更好地反映土体应力应变的实际特性.在边坡稳定分析中，相比其他D-P类准则，建议的D-P准则计算得到的边坡稳定安全系数与条分法结果十分吻合.在地基极限荷载的求解上，所得的极限荷载与滑移线场与Prandtl理论解趋于一致.

A New Druker Prager Type Criterion and Its Implementation〓

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.