2002 Volume 78 Issue 8 Pages 250-255
This paper presents an approach for identifying the parameters in elasto-plastic constitutive model for soil while controling the boundary conditions, e.g., the history of loading, and points out the role of the time update scheme of Kalman filtering in an inverse analysis. For elasto-plastic material, the deformation of the body depends on the loading history, the parameters of the constitutive model, and the initial stresses, whereas only the current stress state determines the deformation of elastic material. It is shown here that a saturated soil deposit provides various settlement curves under different patterns of external action, such as embankment loading and excavation, via finite element computation using an elasto-plastic model. Without precise knowledge of the loading history, however, it is difficult to identify some parameters of the elasto-pl astic material.The formulation of an inverse problem, using the Kalman filter, is examined to overcome this difficulty, while incorporating the transient loading history into the deterministic control input of the state equation.