Estimating Floor Design Spectra at the Top of a Dam Using Dam Response Spectrum Analysis Results
June 13, 2022Floor Design Spectra (FDS) are developed to be used in the response spectrum analysis of the dam appurtenant structures such as gates, and hoists. They are also used for selection of equipment for a prescribed level of shaking and deciding about seismic isolation of some components. The comprehensive way of determining the FDS is through performing time-history analyses on a finite element model of the dam using a set of seismic records. These seismic records are typically compatible with the target ground spectrum at the location of the dam. Time-histories of the response at the location of the appurtenant structures and equipment are used to compute floor design spectra for their analysis and design. A simplified solution for estimating the floor spectra is presented in this study. In this solution an estimate of the floor spectra is computed by properly combining the modal responses at the location of the appurtenant, which are obtained from a typical modal analysis of the dam. This simplified solution could be part of a progressive analysis and be used in the initial design, assessment or equipment qualification. This paper presents the simplified solution followed by a case study of this solution for an appurtenant structure.
Rasekh, A. 2022. “Estimating Floor Design Spectra at the Top of a Dam Using Dam Response Spectrum Analysis Results,” in Proceedings of the 27th International Congress on Large Dams, May 27 – June 3, 2022. Marseille, France. Paris, France : ICOLD (International Commission on Large Dams).