Experimental Investigation on the Effectiveness of Masonry Columns Confinement Using Lime-Based Composite Material

In this paper, the former results of an experimental campaign on the confinement effect of masonry square columns with FRCM composites wraps made of a tex-tile embedded in a natural lime-based matrix are presented. The experimental re-sults confirm the effectiveness of such a composite for increasing both the strength and ductility of axially loaded members, despite its low mechanical prop-erties. These results are compared to the numerical ones obtained applying predic-tive formulas taken from the current literature. However, prediction of the strength increase provided by formulas taken from the literature and from the Ital-ian guideline CNR-DT 215/2018 do not seem capable to fit the results obtained experimentally. The reason of this can be attributed to the very low mechanical properties of the natural matrix used to form the composite. Therefore, consider-ing that the use of a natural matrix, i.e. a sustainable material compatible with the masonry member, is a fundamental requirement for strengthening masonry col-umns of buildings belonging to the architectural heritage, the authors believe that a subsequent effort should be made from the scientific community involved in this field to derive formulas capable of taking into account even composites made with very weak matrices.