FLAX-TRM for the In-Plane Shear Strengthening of Masonry

Abstract:

The present study investigates the use of Flax Textile-Reinforced Mortars (FTRM) as a strengthening and seismic retrofitting solution for unreinforced masonry. The FTRM system comprised flax textiles embedded in lime-based mortar and was externally bonded to the surface of four medium-scale masonry walls on both sides, in strengthening configurations including one and two FTRM layers. One bare wall and one wall strengthened only with lime-based mortar were additionally examined as reference samples. All specimens were tested in in-plane shear under quasi-static cyclic loading conditions, while axial load equal to 10% of the masonry compressive strength was constantly applied throughout the test. The effectiveness of the developed FTRM system is assessed in terms of strength, deformability, energy dissipation and failure modes. The obtained results highlight the promising potential of this system as an in-plane strengthening solution for masonry, with FTRM-retrofitted specimens able to promote strain redistribution and ensure the structural integrity. Two-layer configurations were evidenced to sustain up to 118% higher load capacity, improved ductility, and provided significant energy dissipation capacity.

• Periodical: Key Engineering Materials (Volume 916)
• Pages: 443-448
• DOI: https://doi.org/10.4028/p-kkwuy4
• Online since: April 2022
• Authors: Niki Trochoutsou*, Kypros Pilakoutas, Maurizio Guadagnini
• Keywords: Flax, In-Plane Shear, Masonry, Strengthening, TRM

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