COMPARISON STUDY OF STRESS-DEFORMATION NUMERICAL MODELING OF A ROCKFILL DAM IN THREE and TWO-DIMENSIONAL CONDITIONS

In some cases the two-dimensional analysis in geotechnical problems are not appropriate and threedimensional analysis are necessary. Such conditions can arise when soil conditions vary threedimensionally, when the response of the three-dimensional structures is of interest, and when problem boundaries vary three-dimensionally. The last case includes earthfill and rockfill dams in narrow and deep valleys. This paper presents the stress-deformation analysis results of a rockfill dam in three and twodimensional conditions using geotechnical soft wares of FLAC3D and FLAC2D under different conditions of loading. The results show some errors in evaluation of deformations in two-dimensional analysis in comparison with three dimensional, which are because of the effect of third dimension. However, there is a good agreement between stresses in two and three-dimensional conditions.