Integrative experimental and numerical study of ASR affected nuclear concrete containments

Abstract

The alkali silica reaction (ASR) is a complex multifaceted deleterious one with broad implications on the structural integrity of a nuclear concrete containment (NCC). When compounded with seismic excitation, the structural assessment is even more complex, specially when its intrinsic shear strength is not yet well understood. This paper will highlight 3 years of a holistic research on the pre-cited problem, highlighting the interaction of various tasks, while details can be found in referenced publications. The reported work is broken into four integrated parts: (a) Design of a reactive concrete mix representative of the one in an NCC and likely to expand sufficiently within 6 months; (b) Specimens expansion monitoring in terms of different dimensions and reinforcement ratios for a year; (c) Large-scale testing of shear specimens to evaluate both material (no reinforcement) and structural (with reinforcement) components to assess impact of ASR; and (d) 3D probabilistic nonlinear seismic analyses of an NCC subjected to 40 years of ASR expansion followed by multiple dynamic excitation. It will be shown that the true shear strength of concrete material is affected by ASR, and that this reduction will reduce the seismic resistance of an NCC.