Nonstationary Thermodynamic Analysis of a Chosen Critical Detail in a Waterproof Concrete Basement Structure Using an Experimentally Verified Model

Abstract:

When concrete structures with specific performance requirements call for cracking to be avoided, a reliable crack assessment of hardening concrete members is a crucial task for the design. Concrete walls cast onto already hardened foundation slabs represent an example of externally restrained members commonly subjected to strains resulting from early-age movements. As a consequence, unacceptable cracks may develop. The key parameter for a reliable design of such members is a correct assessment of the hardening phase with respect to the deformation behavior followed with parallel evolution of stiffness and strength properties.This contribution aims to present a macroscopic numerical thermodynamic model which can be used for solving the transient thermal field of a chosen structural detail subjected to thermal loads during early ages. In connection with stress development control, the model represents a mechanical based crack assessment tool for hardening concrete members. Its applicability is discussed at a model solution of a wall-to-slab connection detail in a waterproof concrete basement structure. The model outcome values are verified using data from experimental field measurements.

• Periodical: Key Engineering Materials (Volume 738)
• Pages: 47-57
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.738.47
• Online since: June 2017
• Authors: Miroslav Ignacak, Lydia Matiaskova*, Július Šoltész
• Keywords: Early Age Crack Formation, Finite Element Method (FEM) Based Simulation, Hardening Concrete, Stress Development, Thermal Development

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