Numerical modeling on seismic behaviors of two different composite dams [Modélisation numérique du comportement sismique de deux barrages composites]

Abstract

Composite dams are built with a combination of concrete and rockfill and are used in locations with different types of foundation. Although a composite dam may solve a geological issue, it also has a critical disadvantage with the difference of stiffness at the interface that may lead to a problem in an earthquake situation and cause the failure of the whole dam. Difficulties in modeling composite dams mean that little research has been done on seismic behavior as it is hard to decide the input parameters and reflect the geometric complexity. Dynamic centrifuge tests are used to represent the insitu conditions, but it is nonetheless difficult to measure displacement quantity at the interface. This paper looks at numerical modeling as a means of considering horizontal displacement at the interface, depending on the shape of the composite dam. Flac 3D software was used to simulate the complex geometry at the interface of the modeled composite dams. Acceleration responses from centrifuge tests were compared with the numerical modeling for validation. The results show that numerical modeling can be used to predict a better type of composite dam against earthquake events.