MECOS is Post-Fukushima OECD/NEA initiative, with the following main objectives:
- To quantify the existing margins in seismic analysis of safety class components and assess the existing design practices within a benchmark activity.
- To make proposals for new design/evaluation criteria of pressurized piping systems, accounting for their actual failure mode under strong input motions.
The first part of MECOS consisted of gathering information on i) current design practices and ii) piping system experimentation carried out around the world that could be suitable for benchmarking. Part 2 is the benchmark itself and Part 3 proposals for new criteria. The purpose of the proposed paper is to present the experimental background and the benchmark exercise.