Preliminary study on influences of model container constraint on large-deformation failure behaviors by centrifuge modeling

In the centrifugal model tests, the scaled model must be placed in the model container to withstand the action of supergravity field. The friction of the container wall and the normal limit constraint must exert an undesired influence on the displacement and deformation behaviors, especially its large-deformation failure behaviors. A large plane strain model container is utilized in the centrifugal model tests in an attempt to represent a large-deformation lateral translation collapse, which occurs in a bulk cargo wharf yard ground during filling of ore heap on trial. The filling process of ore heap on trial is simulated twice, and the normal limit constraint on the left end wall is partially released in the second running. The ultimate bearing capacity of the storage yard ground measured by the two tests is close. However, it is found that the failure degree of lateral translation collapse is significantly different in the two tests. The maximum displacement of the first running is 1 m, and that of the second running is 5.5 m, but still smaller than the prototype 20 m. It is noticed that the normal limit constraint on the end wall seriously affects the model failure behaviors. Partially releasing the normal limit constraint on the end wall, to a certain extent, helps to reproduce large-deformation failure phenomena in prototype. The main cause for significant difference in failure degree between the model and the prototype is that a three-dimensional large-deformation damage problem in the prototype is simplified into a two-dimensional plane strain problem to be simulated. The length simulated by container width is much smaller than that of the prototype collapse, resulting in that the model soil failure lacks enough soil supply as in the prototype so that the advanced distance and severity of soil failure of the model is much less than those of the prototype. Therefore, the influences of the above constraints of the model container must be fully considered in the centrifugal model tests on large-deformation failure.