A multi-scaled approach for reinforced concrete walls and its application to pwr reactor contaainment walls.
V. Koundy, E. Guillon, Q.C He, ninth conference on computing in civil and building engineering, 3-5/04/2002, Taipei, Taiwan.
This work presents a simplified structural analysis procedure based on a multi-scaled approach and applies it to reactor containment scale model. This procedure includes three main stages. The first stage, based on Mori-Tanaka's theory, homogenises constitutive reinforced concrete and permits the development of a simplified model for confinement walls. The second stage uses the 3D Finite Element code Castem 2000 to calculate the global behaviour and identify the critical zones of the homogenized structure. A quarter of MAEVA (the French large-scaled model of a large dry containment of pressurized water reactor (PWR)) is modelled and the effects of pre-stress are examined numerically. The last stage consists in determining, at the microscopic scale, the real local quantities (such as stresses) in the critical zones of a structure. Our work shows that, when appropriately utilised, Mori-Tanaka’s model is also a valuable tool in analysing the mechanical behaviour of cylindrical containment buildings made of concrete. The proposed procedure allows to capture essential information relative to the linear mechanical behaviour of the structure before its first cracking, which is quite useful in the parametric calculations necessary for a Probabilistic Safety Assessment (PSA) of nuclear reactor containment.
This work has been done with the collaboration of E. Guillon (stagiaire ENS Cachan, Qi-Chang He, Université de Marne la Vallée.