OECD/NEA Cabri Water Loop Project

The Cabri Water Loop Project is investigating the ability of high burn-up fuel to withstand the sharp power peaks that can occur in power reactors due to rapid reactivity insertion in the core. These are referred to as reactivity-induced accidents (RIA). The project stems from previous Japanese and French tests conducted on high burn-up pressurised water reactor (PWR) fuel that in a few instances exhibited failure at relatively moderate energy deposition levels. The Cabri project aims to extend the database for high burn-up fuel performance in RIA conditions and more importantly, to perform relevant tests under coolant conditions representative of PWRs.

The project began in 2000 and will run until 2015. The experimental work will be carried out at the Institut de radioprotection et de sûreté nucléaire (IRSN) in Cadarache, France, where the Cabri reactor is located. Programme execution can, however, involve laboratories in participating organisations (for instance, in relation to fuel characterisation or post-irradiation examinations).

Twelve tests are proposed as a basis for co-operation with IRSN partners in the Cabri Water Loop Project: these experiments include R&D tests, combined with suitable tests to validate the extrapolation to a broad spectrum of reactor cases. The experimental programme is being reviewed by the project steering bodies and consists (in principle) of the following series of tests:

Two tests have been carried out so far using fuel with very high burn-up and modern cladding materials. Subjected to energy injection beyond what is expected for power reactor cases, the two test fuel rods did not fail during the tests carried out in 2003. Planned future tests will aim to develop a consistent set of objectives and suitable fuel specimens. Post-irradiation examinations of the two tests that have been carried out so far were undertaken in 2004. They involved destructive examinations and investigated in particular the effect of hydrogen on cladding properties. The planning of future tests continues, with the aim of developing a consistent set of objectives and identifying suitable fuel specimens. Considerable progress was made on the refurbishment of the Cabri test facility and the preparation of the water loop installation, a process estimated to take three years to complete. The Cabri tests will in the future be complemented by additional RIA tests carried out in the the Japanese Nuclear Safety Research Reactor (NSRR).

Project data

The data abstract is public.

Participating organisations

Project period

March 2000 to March 2015


~ EUR 74 million

Related links


Neil Blundell:

Last reviewed: 7 July 2014