Hydraulic behaviour of a representative structural volume for containment buildings

Abstract

For particular structures like containment buildings of nuclear power plants, the study of the hydraulic behaviour is of great concern. These structures are indeed the third barrier used to protect the environment in case of accidents. The evolution of the leaking rate through the porous medium is closely related to the changes in the permeability during the ageing process of the structure. It is thus essential to know the relation between concrete degradation and the transfer property when the consequences of a mechanical loading on the hydraulic behaviour have to be evaluated. A chained approach is designed for this purpose. The mechanical behaviour is described by an elastic plastic damage formulation, where damage is responsible for the softening evolution while plasticity accounts for the development of irreversible strains. The drying process is evaluated according to a non-linear equation of diffusion. From the knowledge of the damage and the degree of saturation, a relation is proposed to calculate the permeability of concrete. Finally, the non-homogeneous distribution of the hydraulic conductivity is included in the hydraulic problem which is in fact the association of the mass balance equation for gas phase and Darcy law. From this methodology, it is shown how an indicator for the hydraulic flows can be deduced.

Truss vs solid modeling of tendons in prestressed concrete structures: Consequences on mechanical capacity of a Representative Structural Volume

“…Illustrations of the influence of the mechanical damage on the permeability using truss (K 1D ) or solid (K 3D ) elements. The damage -permeability relation is an exponential law as described in [7].…”

“…First created to validate the models developed for the simulation of mechanical behavior of containment structures (Part 1) [7], it gives the opportunity to investigate the role of steel by comparing 1D and 3D cable modeling. The idea is to quantify the influence on the global and local responses of the explicit introduction of the geometrical heterogeneity (parts 3 and 4).…”

Simulation of damage–permeability coupling for mortar under dynamic loads

“…The relationship between isotropic damage and intrinsic permeability has been proposed by Bary and has been used by Majorana and co‐workers and Jason et al . . The formulas implemented by Jason in the context of isotropic (scalar) damage read with K 0 as the intrinsic permeability of undamaged material, K as the intrinsic permeability of damaged material, D 0 as the damage threshold under which permeability is not affected by damage and D as the damage scalar in an isotropic model.…”

“…The experimental characterisation of this relation has been illustrated in Refs [25][26][27]. The relationship between isotropic damage and intrinsic permeability has been proposed by Bary [28] and has been used by Majorana and co-workers [29] and Jason et al [27]. The formulas implemented by Jason [27] in the context of isotropic (scalar) damage read…”

The Use of Sorption Balance for the Characterization of the Water Retention Curve of Cement-Based Materials

“…In the case of containments for instance, concrete drying conditions the delayed deformations (drying shrinkage and creep) (Granger et al 1997;Brooks 2005;Adam and Taha 2011) and cracking impacts on the confinement capability of the gases within the containment buildings (Lydon and Mahawish 1991;MonlouisBonnaire et al 2004;Jason et al 2007;Verdier and Carcassès 2004;Billard et al 2005). The description of the transport of water therefore constitutes the first phase in the assessment of the durability of concrete structures.…”