Sensitivity of Numerical Seismic Response of Concrete Gravity Dams to Mesh-Size and Foundation Rock Stiffness

Seismic safety of concrete gravity dams can only be assessed based on the results of numerical modeling.Even though the Pine Flat Dam of California, USA, has been extensively studied, by numerical simulation, yet none has been focused on the effect of mesh size and foundation moduli on the responseof this dam. To study these, computer code, EAGD-84, with its open source, was used. Using this code, several linear time history analyses with four different mesh sizes and three different values for rock modulus of elasticity, when subjected to Taft Earthquake of 1952 were studied in the present research. The results indicated that stresses and displacements vary significantly by decreasing the mesh size, usually asymptotically approaching certain values as the size decreases. As for the foundation modulus, it was concluded that the stresses increase by increasing the modulus and the displacements decrease, and vice versa.

Keywords:

Sensitivity Analyses , Concrete Gravity Dam , EAGD-84 , Element Size , Foundation Rock Stiffness