Microstructure Homogenization of Concrete Used in Nuclear Power Plants

Published

December 31, 2020

Author(s)

Edward Garboczi, Christa Torrence, Zachary Grasley, Aishwarya Baranikumar, William Lawrimore

Abstract

Nearly all nuclear power plants in the United States are operating past their intended lifetimes or are requesting lifetime extensions. Therefore, understanding changes to the concrete containment structure over time is crucial to evaluate the structure's continued viability. Concrete materials are heterogeneous particulate composites that exhibit viscoelastic material properties, which can lead to slow deformation over time, causing stress redistribution and the potential for creep cracking. A code to generate random, 3D concrete microstructures has been developed and paired with finite element analysis to predict the long-term viscoelastic properties of concrete. Data from these simulations are used to develop constitutive equations for the viscoelastic behavior of the homogenized concrete. The codes in this work are used to virtualize laboratory experiments, to obtain long-term creep data in a faster, cheaper manner. To validate this work, the simulated creep behavior of concrete is compared to 800 d of experimental data that has been extended to 27 y of data using the Time-Temperature superposition (TTS) principal. Excellent agreement between the simulation results and experimental data is seen.

Citation

Nuclear Engineering and Design

Volume

374

Pub Type

Journals

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DOI Link

Keywords

concrete, creep, finite element, time-temperature superposition, microstructure model, nuclear power plant

Citation

Garboczi, E. , Torrence, C. , Grasley, Z. , Baranikumar, A. and Lawrimore, W. (2020), Microstructure Homogenization of Concrete Used in Nuclear Power Plants, Nuclear Engineering and Design, [online], https://doi.org/10.1016/j.nucengdes.2021.111051 (Accessed May 3, 2024)