Flexural and pseudo‐ductile behavior of e‐glass uniaxial and biaxial fabric‐reinforced cementitious matrix: Experimental study and simulation

• Published in: Structural concrete : journal of the FIB 2024-10
• Main Authors: Yousef, Samy, Kalpokaitė‐Dičkuvienė, Regina, Subadra, Sharath P., Lukošiūtė, Stasė Irena
• Format: Article
• Language: English
• ISSN: 1464-4177; 1751-7648
• DOI: 10.1002/suco.202300634

This research aims to study the flexural and pseudo‐ductile behavior of e‐glass biaxial and uniaxial fabric reinforced cementitious matrix (FRCM). Also, the flexural results and load–deformation curves of FRCM samples were numerically simulated using the finite element method (FEM). The experiments were started with preparation of FRCM flexural samples with different types of fabrics (biaxial and uniaxial) and their distribution in the matrix: one layer was put in the middle, two on the top, two on the bottom, and three layers were distributed equally. The surface morphology and cross‐section microstructure of the fabricated FRCM panels and cohesion of fabrics inside of them were observed using an optical microscope. Subsequently, the flexural response of the FRCM samples was measured according to standard EN 196‐1. Afterwards, based on the flexural measurements, the pseudo‐ductile behavior of the FRCM panels in terms of the ductility index (DI) was determined using energy criteria, including Naaman and Grace models. Finally, the crack propagation and flexural load‐deformation curves of FRCM samples were numerically modeled using FEM (LS‐DYNA) to validate the experiential results. The results showed that reinforcement of mortar with glass fabric leads to a significant increase in strain, especially in case of 3 layers/FRCM till 224% (uniaxial) and 110% (biaxial). Also, the uniaxial FRCM samples provided higher flexural load (3600 N) compared with mortar panel (2337 N) and biaxial FRCM (2788 N). In addition, the DI of FRCM samples was significantly improved by embedding 3 layers of uniaxial fabrics up to 152% (Naaman) and 230% (Grace), when compared with neat panel. Finally, the numerical results obtained from FEM provided a high predication to simulate the failure mode of all panels and to model the load–deformation curves with agreement >96%. Based on that, it is highly recommended to use three layers of e‐glass uniaxial fabric to reinforce the cementitious composite and to improve its flexural response.