An Aggregated Non-Destructive Testing (Ndt) Framework for the Assessment of Mechanical Properties of Unreinforced Masonry Italian Medieval Churches

Medieval churches constructed of unreinforced masonry (URM) represent critical assets of Italian architectural heritage. In order to preserve these churches against earthquakes, obtaining robust information regarding their material mechanical characteristics is necessary as part of a reliable structural analysis and strengthening intervention. Given the drawbacks of semi-destructive or destructive testing of heritage material, non-destructive testing (NDT) is the most viable approach to obtain data regarding the mechanical characteristics of the material composing the structure of the churches. However, there are several uncertainties inherent within NDT based on the current state of the art. Thus, two different NDT techniques and two expert judgment-based investigation techniques were applied to 170 specimens belonging to 72 URM Italian medieval churches to assess the quality of the URM and its components. Subsequently, predictive equations that aggregate the different techniques were developed to define some of the critical mechanical properties of the URM (i.e., compressive strength, Young’s modulus and shear modulus). Finally, a partial validation based on NDT and destructive testing of six URM prisms was performed to check the accuracy of the proposed predictive equations.