The present work aims to analyze and calibrate the mechanical description of plastic strain-induced anisotropy and damage coupling by the so-called Concrete Damaged Plasticity (CDP) constitutive model, which is rather well known, also since it has become available within popular FEM platforms, such as ABAQUS, and shall reproduce typical features of failure processes in quasi-brittle materials, such as concrete. This is achieved by combining an effective stress-based non-associative hardening/softening plasticity model with an isotropic damage model based on plastic strains, at a smeared continuum scale. In the paper, focusing on the mere elastoplastic coupling for tensile-dominated responses, and introducing an enhanced tuning by setting tensile exponential softening and damage evolutions through a convenient plastic to inelastic strain ratio parameter, by means of an external user implementation, an exhaustive numerical parametrization analysis is performed, starting at a constitutive-driver level, to experiment with the outcomes of the constitutive description and to quantify the amount of material anisotropy induced by plastic deformation, under biaxial elongation/shearing Willam’s test, which prescribes/involves the rotation of the principal axes of strains/stresses. It is shown that the constitutive response is effectively regularized, allowing to fulfil the requirements of Willam’s test, independently of the amount of inherent plastic dilatancy, showing a rather mild presence of plastic-induced anisotropy, at the pure constitutive-driver scale. Furthermore, first extrapolating implications and outcomes at the small (specimen) structural scale are also investigated, with clear appearance of strain localization and related much pronounced plastic-induced anisotropy, in the (imperfection-triggered) macroscopic response, with features that are similar to those coming, for example, from more sophisticated anisotropic damage models, while significant practical applications may subsequently follow, within different structural engineering contexts, such as that of large-scale concrete structures under static and dynamic loading scenarios, toward informed safety assessment and evaluation.
This chapter outlines a qualitative meta-analysis of the analyses of the social representations of three variants of otherness (i.e., immigration, Islam, and LGBT people). The meta-analysis aimed at assessing the level of generalization of the latent semantic structures detected by first-level analyses with the purpose of testing two general hypotheses drawn from Semiotic Cultural Psychology Theory (Salvatore in Psychology in black and white. The project of a theory-driven science. InfoAge Publishing, Charlotte, NC, 2016; Valsiner in Culture in minds and societies. Foundations of cultural psychology. Sage, New Delhi, India, 2007). First, that the social representations of social objects are shaped by affective sense-making. Second, that the higher the degree of exposure to otherness conveyed by the specific object of the social representation, the more the salience of affective sense-making, hence its influence over social representation. The findings were consistent with both hypotheses. (a) The meta-interpretation of the semantic structures in terms of generalized affective meanings reached a high level of coverage: almost four out of five semantic structures identified by the first-level analyses were interpreted as a specimen of more general affect-laden, generalized meaning. (b) The salience of affective sense-making proved to be associated with the degree of exposure to otherness involved in each object. The more the object involved the exposure to otherness, the more similar the semantic structures were. These results suggest that the representation of a specific topic should be regarded as a local expression of the general cultural dynamics.
In this work the comparisons between measured and numerically simulated tracer experiments are presented for two different datasets. Different versions of the model system RMS, including the Regional Atmospheric Modelling System (RAMS) and the dispersion model SPRAY, accounting for alternative turbulence closures are used. These last are the Mellor and Yamada model level 2.5 and two versions of the E-l model, the standard isotropic and anisotropic versions. Moreover, simulations performed with the CALPUFF dispersion model coupled with RAMS are also presented. The wind fields and the ground level concentrations produced by the two model systems are shown and compared.
In 1996, EDF decided to build a containment model at the scale 1:3, the MAEVA mock-up, in order to check and study the behaviour of a pre-stressed concrete containment vessel without a liner in terms of mechanical strength and leaktightness, for loadings corresponding to its design and beyond design conditions. In parallel with the construction and testing of the mock-up, a cost-shared R&D action supported by the European Union, the CESA project, is dealing with quantification of leak rates through concrete cracks and porosity, predictive calculations of the behaviour of the mock-up and analysis of the experimental results. In this paper, we propose a synthesis of the main theoretical and experimental results, obtained after 2.5 years. It should however be noted that, due to some unexpected delays in the experimental programme, quite natural with such a huge and unique experimental set-up, only the design-basis accident sequences, already performed, have been reported in this paper. The first results are nevertheless very interesting, both from a scientific and nuclear utility point of view.
