Investigation of the effect of soil structure interaction on the behavior of concrete faced rockfill dams and assessment of current analysis methodologies

Thesis Type: Postgraduate

Institution Of The Thesis: Middle East Technical University, Faculty of Engineering, Department of Civil Engineering, Turkey

Approval Date: 2012

Thesis Language: English

Student: Emrah Erşan Erdoğan

Supervisor: YALIN ARICI


CFRD (Concrete Faced Rockfill Dam) construction becomes more frequent recently not only because of its secure nature, but also its economical cost where its built up material is feasible to obtain. Although CFRDs are known to be safe compared to other dam types, it is behavior during an earthquake loading still not a well-known aspect since it is mostly constructed in regions of low seismicity until now. Considering this fact, this study‟s primary purposes are set to find the mathematical model size of a “large” domain model to correctly simulate the Soil-Structure Interaction (SSI) effects, to investigate the reliability of the current simulation methods applicable to the modeling of CFRDs and to observe nonlinear performance of CFRDs, mainly focusing on the performance of the face slab. Results of this study clearly state an adequate model size to simulate the SSI effects correctly using the finite element method with the help of the previous studies. The change of the response of the dam depending on the dam and underlying soil moduli and depth is presented clearly. Besides the testing of the performance of a simplified model, the reliability of this approach is judged and found to be not accurate enough when compared to theoretically “exact” results. Crack occurrence on the face slab during a non-linear analysis is presented, its importance is discussed both in magnitude and pattern. A significant spreading of cracking after an earthquake loading is observed.