L. Kalani Sarokolayi, B. Navayi Neya, Javad Vaseghi Amiri,
Volume 13, Issue 1 (3-2015)
Abstract
This study focuses on non-linear seismic response of a concrete gravity dam subjected to translational and rotational correlated components of ground motions including dam-reservoir interaction. For this purpose rotational components of ground motion is generated using Hong Non Lee improved method based on corresponding available translational components. The 2D seismic behavior of the dam concrete is taken into account using nonlinear fracture mechanics based on the smeared- crack concepts and the dam-reservoir system are modeled using Lagrangian-Lagrangian approach in finite element method. Based on presented formulation, Pine Flat concrete gravity dam is analyzed for different cases and results show that the rotational component of ground motion can increase or decrease the maximum horizontal and vertical displacements of dam crest. These results are dependent on the frequency of dam-reservoir system and predominant frequencies of translational and rotational components of ground motion.
R. Tarinejad, S. Pirboudaghi,
Volume 13, Issue 2 (6-2015)
Abstract
It is well-known that dam-reservoir interaction has significant effects on the response of dams to the earthquakes. This phenomenon should be considered more exactly in the seismic design of dams with a rational and reliable dynamic analysis method. In this research, seismic analysis of the dam-reservoir is studied as a wave propagation problem by using Legendre Spectral element method (SEM). The special FEM and SEM codes are developed to carry out the seismic analysis of the dam-reservoir interaction system. The results of both SEM and FEM models are compared considering the accuracy and the time consumption of the analysis. Attractive spectral convergence of SEM is obtained either by increasing the degree of the polynomials in the reservoir or by the number of elements of dam. It is shown that all boundary conditions of the reservoir domain in the SEM are evaluated by the exact diagonal matrices. The SEM leads to the diagonal mass matrix for both dam and reservoir domains. The stiffness matrices obtained from the SEM are more sparse than the corresponding stiffness matrices in the FEM consequently the SEM needs a significant less time consumption of the analysis.
