Application of a response spectrum method specific modification to seismic upgraded reactor coolant loop of NPP with VVER 1000

摘要

For the seismic upgrading of the reactor coolant loop of NPPs with VVER reactors operated in Czech Repubic, Slovak Republic and Hungary a typical measure is the application of GERB viscodampers. In the development of the equation of motion, the dampers can be modelled using two or three parametrical rheological mdoels. In all cases the damping matrix of the analyzed system is a non-classic and consist of proportional and frequency dependent parts. Also stiffness matrix consist of constant and frequency depent parts