MOdihMA at Sforza Castle in Milano: Innovative Techniques for MOisture Detection in Historical Masonry

Abstract The research line MOdihMA (MOisture detection in historical 7 MAsonry) proposes to improve the innovative techniques recently developed to 8 measure different parameters related to water content in masonry, that has an important role in the damage of historical buildings. The first objective of this project is to compare the effectiveness of the different methods in understanding how the quantitative data obtained are directly related to water content. The second objective of the MOdhiMa project is to compare the ability of the different techniques to map water as a function of its location and depth within the masonry structure, both on macro and micro-scale. A selection of these innovative techniques recently had an application on the "Sala delle Asse" in the Sforza Castle in 16 Milan. The hall is famous for the decoration of the vault and the monochrome on 17 the northwest wall, attributed to Leonardo. Recently Milano Municipality defined the plan of diagnostics for detecting the causes of the increasing damage on the 19 painting and the poor conditions of conservation of the vault. Unilateral NMR, SUSI, IR Thermography, gravimetric and chemical tests were applied for mapping 21 the moisture distribution in the bottom of the northwest wall. The comparison with 22 the results of the standardized techniques confirmed the low moisture content 23 distributed in the masonry