COMPARISON OF TWO-DIMENSIONAL AND THREE-DIMENSIONAL DYNAMIC RESPONSE OF AN EARTH AND ROCKFILL DAM

This study compares the 2D and 3D dynamic response of a rockfill dam for water storage, which will be located in southern Peru, in a zone of high seismicity. The geotechnical characterization of the materials that compose the dam and the foundation was estimated based on field and laboratory geotechnical investigations. The synthetic seismic records used in the dynamic analyses were obtained from the spectral matching of representative earthquake records, which were previously corrected for baseline and filtered. A numerical modeling strategy is presented, employing the finite element methodology by using constitutive models such as Hardening Soil (HS) and Hardening Soil Small Strains (HS-Small). As part of the results, higher displacement and deformation values were obtained from the 2D dynamic analysis, unlike the acceleration, where higher values were obtained from the 3D dynamic analysis. The 2D structural period of the dam is greater than the 3D period, which demonstrates a strict dependence of this parameter on the geometry of the dam and its topography. Finally, the results obtained in this study show us a notable difference between the 2D and 3D dynamic response of the dam, so it is important to consider 3D dynamic behavior in the design of this type of geotechnical structure.