NEA Cabri Water Loop Project

The CABRI International Project (CIP) investigates the ability of both uranium dioxide (UO2) and mixed-oxide fuel (MOX) pressurized-water reactor (PWR) fuels to withstand sharp power transients that would arise from rapid reactivity injection in the core, i.e. so-called reactivity-initiated accidents (RIA). The project stems from earlier Japanese and French tests conducted on high burn-up PWR fuel that, in a few instances, exhibited failure at relatively moderate levels of injected energy. CIP aims to extend the database for high burn-up fuel behaviour and, importantly, perform the majority of tests in conditions representative of PWR RIAs. The experimental programme is undertaken by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN) at Cadarache, France, where the CABRI facility is located. The programme may also involve laboratories of partners relating to, e.g. fuel characterisation or post-irradiation examinations (PIEs).

CIP partners determine the test conditions where the experimental programme is regularly reviewed by the Technical Advisory Group and the project is overseen by the Steering Committee. CIP comprises twelve tests where the first two tests, CIP0-1 and CIP0-2, have been performed in the original sodium loop of the CABRI facility. The test matrix evolves as CIP progresses but an illustration is provided below.

The CIP tests are complemented by pulse-irradiation tests performed in JAEA’s Nuclear Safety Research Reactor (NSRR), e.g., Fuketa et al., (2006), J. Nucl. Sci. Technol. 43(9).

Project Status

The project began in March 2000 and, in 2002, CIP0-1 and CIP0-2 were performed using fuel of very high burn-up with M5 and Zirlo claddings. Subjected to energy injection beyond that expected in power-reactor situations, neither rodlet failed. PIEs involving destructive examinations in 2004 investigated, in particular, the effect of hydrogen on cladding properties. Since then, IRSN has been engaged in a programme of conversion to a water loop and considerable upgrading of the facility. In October 2015 the French nuclear safety authority (ASN) issued its final authorisation for the reactor of the refurbished CABRI facility to restart and the first criticalities were produced on 20 October 2015. The first test in the water loop, CIP-Q, is planned in early 2017 and, subsequently, IRSN will be in a position to perform 2 tests per year where rodlets for the first five tests are already prepared. Completion of the project will perhaps be accomplished by 2021.

Project data

The data abstract is public.

Participating organisations

Project period

January 2000 to December 2015


~ EUR 74 million

Related links


Martin Kissane:

Last reviewed: 17 November 2015