Abstract:In?actual?engineering,?the?retaining?walls?and?foundation?pit?excavation?could?be?regarded?as?plane?strain?problems?considering?the?influence?of?intermediate?principal?stress?on?the?strength.?The?intermediate?principal?stress?relationship?of?Lade-Duncan?strength?criterion?under?plane?strain?conditions?is?substituted?into?SMP?and?Lade?-Duncan,?AC-SMP?and?the?generalized?Mises?strength?criterion,?and?we?obtained?the?new?plane?strain?strength?criterions.?Based?on?these?new?strength?criterions,?active?and?passive?earth?pressure?calculation?formulas?were?established,?and?then?extended?to?cohesive?soil.?The?theoretical?and?measured?values?were?compared?and?analyzed.?The?results?show?that?the?effect?of?intermediate?principal?stress?on?earth?pressure?is?significant.?The?Mohr-Coulomb?strength?criterion?fail?to?consider?the?influence?of?intermediate?principal?stress,?calculation?results?are?more?conservative?than?the?actual?measurement.?Because?of?considering?the?influence?of?the?principal?stress,?the?results?of?SMP?strength?criterion?and?Lade-Duncan?strength?criterion?are?closer?to?the?actual?measurement?than?the?Mohr-Coulomb?strength?criterion.?The?AC-SMP?strength?criterion?and?the?generalized?Mises?strength?criterion?can?describe?the?earth?pressure?of?the?retaining?wall?within?a?certain?range?of?friction?angle,?but?when?it?exceeds?the?applicable?range,?both?are?no?longer?suitable.?The?calculation?results?of?the?generalized?Mises?strength?criterion,?in?the?applicable?range,?are?closer?to?actual?data?compared?with?the?results?from?the?SMP?strength?criterion?and?Lade-Duncan?strength?criterion.?These?results?can?provide?some?theoretical?guidance?for?the?earth?pressure?calculation?of?the?retaining?structure.