BRICK MASONRY COMPRESSIVE STRENGTH EVALUATION: COMPARISON BETWEEN PREDICTIVE MODELS

The evaluation of the safety of existing masonry constructions is a crucial and current issue, especially for countries characterized by the presence of a large number of old and ancient buildings. Within the vulnerability assessment procedures, one of the most important phases is the evaluation of the material mechanical properties. Several investigation techniques can be adopted, classified as non-destructive, minor-destructive and destructive according to their invasiveness on the construction. To determine the compressive strength of existing masonries, tests on the masonry components, bricks and mortar, can be performed. Predictive models or empiric formulations can then be used to evaluate the masonry compressive strength, starting from the mechanical properties of the constituents. The objective of the present research is to determine the capability of predictive models to effectively capture the masonry compressive strength. For this purpose, a database of experimental tests conducted on existing masonry buildings was collected, together with data from the literature. In particular, the masonry compressive strength and the strength of bricks and mortar were experimentally evaluated or derived from previous researches. The predictive models chosen were applied, using the brick and mortar properties, and the results were correlated with the masonry compressive strength, considered as a reference. The investigated masonries were classified according to their strength and different ranges were considered to better evaluate the reliability of the formulations adopted. Critical analyses about the suitability of each predictive model will be presented, with a particular focus about the determination of the compressive strength for poorquality masonries, for which a modified analytical formulation was calibrated.