The French Alternative Energies and Atomic Energy Commission (CEA) and its industrial partners electricite de France (EDF) and AREVA have been developing the collaborative platform PLEIADES for more than 10 years. This platform now supports the development of several state-of-the-art fuel performance codes Alcyone and Cyrano for Pressurized Water Reactor (PWR), Germinal V2 for Sodium Fast Reactors (SFR), Licos for innovative fuel elements and experimental irradiation devices, MAIA for Material Testing Reactors (MTR), etc.This paper first provides an up-to-date overview of the PLEIADES platform and then focuses on recent improvements of the thermomechanical modelling abilities recently introduced in PLEIADES's fuel performance codes. Various topics will be discussed and illustrated using Alcyone simulations of the PWR fuel rod in normal and off-normal situations, including LOCA and RIA- PWR fuel pellet cracking during the reactor start-up;- description of grain boundary decohesion in the fuel oxide during a RIA transient;- multi-fragments modelling of the PWR in 2D(r; );- various numerical improvements ;- finite strain modelling in 1D.