Title: Pseudo-Ductile Cementitious Composites by Hierarchical Crack Bridging

Author(s): B. S. Sindu and Saptarshi Sasmal

Publication: Materials Journal

Volume: 119

Issue: 1

Appears on pages(s): 145-158

Keywords: continuous fibers; high strength; hybrid fibers; inverse analysis; length scales; numerical modeling; strain-hardened

DOI: 10.14359/51734193

Date: 1/1/2022

Abstract:
An attempt has been made to develop hierarchically crack-abridged, strain-hardened cementitious composite by judiciously incorporating hybrid fibers of three distinctly different length scales (nano-, micro-, and continuous fibers). Unlike textile-reinforced cement composites, here, the nano- to macrofibers are used to improve the cementitious matrix properties through appropriate crack bridging, and at the macroscale, only onedimensional (1-D) long fibers/yarns are used. A distinct and categorical improvement in the property(ies) is found to take place at each scale of bridging. The structural composite systems made using the developed composite exhibited very promising properties, such as high strength (flexural) of approximately 20 MPa (2.90 ksi), an ultimate strain of 8000 με, and rotational capacity of approximately 10 degrees. A detailed numerical model is developed to carry out nonlinear finite element analysis where the interface properties, strain state, and so on are the parameters. Finally, a constitutive model is proposed for the developed composite through inverse analysis. The proposed constitutive model will help engineers design structural components/retrofit schemes by employing the developed composite without complex analysis (using smeared properties).