Final safety design of the Cumbindanovu dam in Sardina: A combined approach of geotechnical and structural engineering

Final safety design of the Cumbindanovu dam in Sardina: A combined approach of geotechnical and structural engineering

Katterbach, M.

Hack, H.R.G.K. (mentor)
Hegg, U. (mentor)
Maurenbrecher, P.M. (mentor)
Van Paassen, L. (mentor)
Ngan-Tillard, D.J.M. (mentor)
Amberg, F. (mentor)

Civil Engineering and Geosciences

Geo-Engineering Section

2009-11-30

The lack of adequate integration of geology and engineering into the design of engineering structures might have significant undesirable consequences. It appears that all too frequent the interface between the engineering structure and the natural environment, such as the dam foundation, presents a virtual interface between both disciplines of engineering and earth science, respectively . This work demonstrates how to integrate both disciplines into the final design of an engineering project, using the example of the Cumbidanovu dam in Sardinia. Foundation stability is one of the most important factors influencing the safety of a concrete dam and has been one of the key technical problems in the design of the studied dam project. The central research question to be answered, is if the latest final design of the Cumbidanovu dam complies with the standards for safety and if it is economically sound. To do so, the following four central hypotheses and theories are verified during this work. 1) A critical assessment of sliding safety should be based on a high quality data base. Therefore a further refinement of the already available data of the Cumbidanovu dam site is required. The data acquisition should involve both simple and sophisticated means; 2) The safety factors for the planned Cumbidanovu dam with its complex foundation conditions can be increased by improvements; 3) Cooling of the dam during and after construction is necessary in order to ensure dam stability, which might be affected by crack initiation and temperature discrepancies; 4) The global stability assessment of the Cumbidanovu dam with its encountered complex foundation rock mass requires the combination of structural and geotechnical considerations. Structural and geotechnical aspects should be properly integrated into the overall dam design in order to achieve dam safety with an optimized final design. The desk study at the beginning provides an insight into the actual site conditions as well as their future development. Adapted to this outcome, a field survey is planned and conducted in order to determine the variations with time and work progress. Special attention is paid to the possibilities and limitations of geomechanical classification system. It is shown how to obtain a sound geomechanical data basis by simple means and the corresponding data processing. Especially, for the studied dam site, which is characterized by complex foundation characteristics, a careful geomechanical evaluation is indicated in order to estimate the influence of the rock mass on the dam structure. The acquired data are subsequently integrated into the structural analyses, which are recommended to evaluate the dam stability. By using different geomechanical and structural approaches, it is possible to cross-verify the results. The procedure of this work, which integrates both structural and geotechnical aspects into design considerations finally allows to come up with a suggestion for a safe final dam design, which in the end emphasizes the potential of engineering geology.

civil engineering
geoscience
dam
site investigation
foundation

http://resolver.tudelft.nl/uuid:dad1d94d-e2e5-4820-9d87-6862628c2519

Student theses

master thesis

(c) 2009 Katterbach, M.