In view of the structural characteristics of natural soft soil

a damage parameter for reflecting structural disruption is proposed in order to consider a continuous structure damage process of soft soil. Damage function is introduced in elastic and plastic modulus expression of the bounding surface formulation directly; then a bounding surface damage model for structural soft soil is developed; the complication induced by introducing damage parameter into the bounding surface equation is avoided and its numerical implementation is easy for the analysis of earth structures. The theoretical predictions are compared with triaxial drained and undrained compression test results of a marine soft soil; it is shown that the model is reasonable.