The result also reveals that the nuclear island is safer in Dien Bien earthquake that it is in El Centro and Kobe earthquakes. The distribution of the von Mises stresses of the structure according to the maximum displacement at the top point is also examined and highlighted. | 14 SCIENCE & TECHNOLOGY DEVELOPMENT, Vol 20, 2017 Seismic Analysis of AP1000 Nuclear Island Structure by Using the Finite Element Software ANSYS Nguyen Dinh Kien, Vu Lam Dong Abstract—Seismic analysis of AP1000 nuclear island structure by using the commercial finite element software ANSYS is presented. Using the ANSYS Workbench, a sophisticated threedimensional finite element model of the structure is created and employed in the analysis. Dynamic response of the structure to both the one-directional and three-directional acceleration time histories are considered in the analysis. The time histories for the relative displacement, velocity and absolute acceleration of the structure are obtained for various earthquakes, including American El Centro, Japanese Kobe and Vietnamese Dien Bien earthquakes. The numerical results show that the dynamic characteristics obtained by using one-directional and thee-directional acceleration time histories are different, and the three three-directional acceleration time histories should be employed in the seismic analysis. The result also reveals that the nuclear island is safer in Dien Bien earthquake that it is in El Centro and Kobe earthquakes. The distribution of the von Mises stresses of the structure according to the maximum displacement at the top point is also examined and highlighted. Index Terms— AP1000, nuclear island, seismic analysis, finite element model, dynamic response, ANSYS. Manuscript Received on July 13th, 2016. Manuscript Revised December 06th, 2016. The work presented in this article has been support by Vietnam Academy of Science and Technology, grant No. . The authors would like to thank Dr. Pham Ngoc Dong of Vinatom and Prof. Buntara Gan of Nihon University, Japan for their kindness to use ANSYS software. Nguyen Dinh Kien is a research associate at Institute of Mechanics, Vietnam Academy
