Analytical study on structural failure mode of 1/4 PCCV test model

The Nuclear Power Engineering Corporation (NUPEC) and the US Nuclear Regulatory Commission (NRC) established a JAPAN-US cooperative research project on the ultimate capacity of nuclear reactor containment vessels subjected to internal pressure. As a part of this research, ultimate capacity pressure tests were carried out on a 1/4 scale prestressed concrete containment vessel (PCCV) model of existing PCCV for pressurized water reactors (PWR) in 2000 and 2001 at Sandia National Laboratories (SNL), USA. In addition, Round Robin pretest and posttest analysis meetings were held, with a view to improving the existing analysis methods for the nonlinear behavior of PCCVs. The Japan PCCV research group consisting of the above six companies participated in these meetings and presented pretest and posttest analysis results obtained in our research program. Many types of global and local analyses on a 1/4 PCCV test model were conducted to establish an analysis methodology in our research program. This paper describes the reliability of the analysis methods developed here for the nonlinear behaviors of PCCV up to ultimate internal pressure. In addition, the possible failure modes of PCCV were investigated by examining deformations and strain distributions of the model obtained from the analysis results. Comparison of the analytical and test results confirmed that pretest and posttest analyses can predict and simulate not only the nonlinear behaviors but also the structural failure modes of the PCCV test model with good accuracy. (author)