Torsional shear of mortar: experimental characterization and multiscale modeling

• Published in: Construction & building materials 2020-09, Vol.254, p.119126, Article 119126
• Main Authors: Hlobil, Michal, Kunecký, Jiří, Koudelková, Veronika, Drdácký, Miloš
• Format: Article
• Language: English
• Subjects: Anti-plane shear fracture (mode III); Cocciopesto mortar; Continuum micromechanics; Digital image correlation; Finite element analysis; Microstructure; Multiscale modeling
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2020.119126

•Torsional shear of thin-walled mortar tubes with fracture after mode III (antiplane shear).•Deformation measurement on curved specimen surface using Digital Image Correlation.•Full microstructural characterization of Portland cement mortar with hydraulic lime.•Upscaling of elastic properties using continuum micromechanics homogenization.•Structural simulation of shear fracture using finite element analysis. This paper presents a multidisciplinary study aimed at characterizing the pure shear behavior of Portland cement-based mortars blended with natural hydraulic lime. Circular thin-walled tube mortar specimens were subjected to pure torsional loading inducing anti-plane shear (mode III) fracture. The deformation of the specimen during loading was assessed on its curved surface using an optical measurement setup based on the digital image correlation technique. Modeling of shear fracture encompassed two sequential steps: i) a multiscale homogenization using continuum micromechanics was employed to upscale the elastic properties of the material based on a thorough microstructural characterization, followed by ii) a full structural simulation of the shear fracture using finite element analysis. The proposed methodology was successfully validated on two distinct loading cases and allows to link the microstructural composition to the structural behavior of the material.