Preliminary Assessment of the Resistance Characteristics and Dynamic Behavior of the San Francisco of Assis Church in Marcapata, Cusco-Perú

The San Francisco de Assis church of Marcapata is a historical rubble masonry with mud mortar structure built between XVI and XVII centuries, located in the province of Quispicanchi, Cusco-Perú. Despite the importance of this monument, structural studies for its conservation and preservation are unknown. Those facts have motivated the realization of this study, with the objective to obtain data for the assessment of its actual structural condition. The paper begins with a brief description of the historical aspects of the Marcapata site and the Church, followed by the on-site structural inspection both at the exterior and interior of the monument. Based on in-situ non-destructive approach, Operational Modal Analysis (OMA) tests was further developed with reference to a representative wall of the monument. The results of the experimental field campaign were used to develop calibrated finite element models of the wall, and to indirectly estimate mechanical characteristics of the masonry. The initial structural inspection revealed the precarious state of conservation of the monument and the need for more detailed studies. Three-ruble-stone-mud-mortar wallets of 60 × 60 × 30 cm³ (height × length × width), made with materials like the original, collected around the site, were subjected to uniaxial compression monotonic load. A maximum compression resistance of 0.82 MPa was obtained. The dynamic properties of west wall of the church were identify through OMA tests. Three highly sensitive piezoelectric accelerometers and a data acquisition system were used. A fundamental frequency of 3.1 Hz was obtained using the enhance frequency domain decomposition approach. OMA tests also allowed to indirectly estimate a modulus of elasticity of 720 MPa for the masonry. The results obtained in this preliminary study will be used in the ongoing structural assessment of the Marcapata Church.