Seismic response of the ACRTM reactor building

The Advanced CANDU Reactor or the ACR. is developed by Atomic Energy of Canada Limited (AECL) to be the next step in the evolution of the CANDU product line. It is based on the proven CANDU technology and incorporates advanced design technologies. Two standard designs of the ACR are developed: ACR-1000 and ACR-700. The ACR is designed to incorporate the latest advances in design and construction techniques and to be cost competitive while achieving higher safety and performance standards. This paper describes the methodology of the seismic qualification of the ACR reactor buildings. The ACR standard plant is conservatively qualified for a design basis earthquake with peak horizontal ground acceleration of 0.3 g and for a wide range of soil/rock foundation conditions. The input design ground response spectra address current technical issues such as earthquake input motions with high frequency content and near field effects. The structural behavior of the ACR-700 reactor building under the design earthquake is determined using two dynamic models. The dynamic characterizes of the reactor building are established using a stick model and a three-dimensional finite element model. In developing the dynamic models, considerations are given to the details of both the containment and internal structures, and to location and weight of major equipment and systems. The soil-structure-interaction effects are considered in the seismic analysis. The structural responses of the reactor building due to the design basis earthquake are determined and are used for the assessment of the reactor building stability. The seismic responses of the reactor building include displacement and acceleration responses and base shear and overturning moments. (authors)