Performance assessment of basalt FRCM for retrofit applications on masonry

Abstract

Abstract An increasing interest and application is nowadays found for composite systems in construction and rehabilitation industry. The consensus on fibre reinforced composite systems was mainly based on high tensile strength, light weight, relative ease of installation, and resistance to corrosion. However, some drawbacks related to the epoxy (hence, organic) matrices of Fiber-Reinforced Polymers (FRP) have been solved by inorganic ones yielding to novel fibre reinforced composites. In these materials the composite action is mainly achieved through mechanical interlock between the matrix (e.g. a cement- or a lime-based mortar or a geopolymer with the option of chopped fibres and/or low-content polymer addition) and the mesh-like fibrous structure (a textile) that allows the mortar to protrude through the grid's openings. Aiming at the investigation of the mechanical properties and the development of testing procedures for this new family of materials (termed herein as Fabric-Reinforced Cementitious Matrix (FRCM)) the present paper presents the results of an extensive experimental program on different combinations of basalt fibre textiles and inorganic matrices organized by RILEM TC 250-CSM (Composites for the Sustainable strengthening of Masonry) involving ten European laboratories. The tests involve more than 100 specimens: half are tensile tests and the other half are bond tests carried out on prisms made of clay bricks, on three different basalt-based FRCM configurations comprising readily available commercial systems provided by different producers. The scope of this work is aimed not only at presenting a comparative performance assessment of different Basalt FRCM systems, but also at providing meaningful criteria to reliably design and analyse retrofit applications. The relevant round robin test program provides valuable data generated during the experimental activity and statistical analysis thereof; then, based on the various testing approaches employed, the advantages/drawbacks of certain testing factors are summarized and critically assessed, reflecting the experience of involved institutions. It is believed that this represents a crucial step in improving knowledge on innovative retrofit applications and developing standard test methods.