Application of a performance-displacement based method for the seismic assessment of earth dams

Abstract

This paper presents the application of a performance-displacement based assessment methodology to characterize the seismic response under several damage or performance-based scenarios of an earth dam. In the applied method, the system displacements are related to spectral accelerations and moment magnitudes in order to evaluate performance or damage scenarios. The earth dam selected for this study is the Carite Dam in Guayama, Puerto Rico. This embankment dam was built in 1913 in different phases with a raised embankment crest for flooding control in 1995. A finite element of the dam was developed to perform several incremental dynamic analyses. The dam geometry and materials properties were estimated based on extensive review of borings logs and technical reports provided by the administrators of the dam. The dynamic analyses were accomplished using seismic ground records with response spectrum made compatible with the design response spectrum from the ASCE-10 standard. Crest horizontal displacements were obtained from the dynamic analyses for different incremental factors and used to estimate moment magnitude and epicentral distances needed to attain the displacement limits.