Dams & Hydro
Geotech
Advanced Numerical AnalysisDynamic Calibration Of The Finite Element Model Of Katse Dam
SANCOLD 2025 ANNUAL CONFERENCE 5-6 November 2025
By Ryan Cassells, ARQ Dams Pty Ltd
-co-author P Moyo, L Phooko, R Hlajoane and L Hattingh
The last Panel of Expert review of Katse Dam in 2018 (Dungar et al: 2019) concluded that the original design calculations although appropriate at the time, do not satisfy all the current international accepted criteria and procedures. This specifically pertains to the abutment seismic stability as well as the overall long-term behavior of the dam wall during normal operation and extreme conditions. In addition, advancements in numerical modelling techniques since the 1990s—when the dam was designed—warranted a state-of-the-art structural evaluation. As a result, the LHDA initiated a project to perform a finite element analysis of the dam as well as evaluate the monitoring system and monitoring results and determine threshold values for the monitoring system.
A key component of the structural evaluation involved developing a finite element model of the dam and foundation for undertaking state-of-the-art simulations of the dam behavior under a suite of loading conditions. The first step in the calibration process of the finite element model of the dam was to perform an eigenvalue back-analysis of the model for comparison with the in-situ measured ambient vibration measurements (AVM measurement). This was achieved by validating the model mass and stiffness parameters through the process of aligning the computed modal characteristics with those measured on site.
This paper will discuss the dynamic calibration approach as well as report on the challenges encountered, and lessons learnt during this dynamic calibration using the ambient vibration measurement results.
Return