Investigation of to the Effect of Bedrock Stiffness on Seismic Behaviour of Roller Compacted Concrete Dam

In this research, the effect of bedrock stiffness on seismic performance of roller compacted concrete (RCC) dam isevaluated using probabilistic analysis. Due to the geometry and behavior of RCC dams, a two-dimensional modeling wasselected for system. Ansys software is used for modeling and analysis of dam-reservoir- foundation system. Newmarkimplicit time integration scheme is developed to solve the time-discretized equations which are an unconditionally stablemethod. The Watana dam, due to San Fernando earthquake has been selected as a case study. In order to propagate theparametric sensitivity to the seismic performance of the system, Monte Carlo simulation with Latin hypercube sampling(LHS) method is used as a probabilistic method and uncertainty analysis. The sensitivity of responses under seismic loadingis reliably examined utilizing different values of ratio of bedrock stiffness to body concrete stiffness as random inputs.Consider to obtained results, it is revealed that the bedrock stiffness how can effect on seismic behavior of concrete gravitydams due to earthquake. Regarding the safety of dams due to compressive stresses, various ways have been assessed toinvestigate the induced tensile stress in the heel and the results have been investigated. Finally, appropriate range of theratio of bedrock stiffness to concrete stiffness of dam body is presented to assess the safety design.

Keywords:

Uncertainty , RCC Dam , Bedrock Stiffness , Latin Hypercube Sampling , Interaction