Deterioration Effects on Bricks Masonry in the Venice Lagoon Cultural Heritage: Study of the Main Façade of the Santa Maria dei Servi Church (14th Century)

Abstract

Tidal exchange, capillary rise, water condensation-evaporation cycles, and crystallization of salts are the main causes of damage in historic brick buildings in Venice. The present study addressed these issues by proposing a study of twenty-three brick samples collected on the main façade of the Santa Maria dei Servi Church (14th century). The color, mineralogical composition, and texture of these samples were studied using standard methods such as spectrophotometry, X-ray powder diffraction (XRPD), optical microscopy (OM), and field emission scanning electron microscopy (FESEM). The presence of carbonates (calcite and dolomite) and newly formed silicate phases, such as gehlenite and diopside, provided indications of the temperatures reached during firing and suggested the absence of a good standardization in the production process. Meanwhile, XRPD and hyperspectral analysis (HA) detected sulfates (e.g., gypsum and mirabilite) as the main weathering products due to the salt decay process that affects monuments in the Venice lagoon environment. Moreover, secondary phases, such as Mg- and Ca-zeolites, occurred in bricks where the groundmass observed by OM was more vitrificated, and the XRPD patterns displayed the highest amorphous content. On-site mapping of sulfates and chlorophyll by HA was also performed on the main façade of the Church, highlighting the large presence of salts and biodeterioration.

Black Crust from Historic Buildings as a Natural Indicator of Air Pollution: A Case Study of the Lipowiec Castle, Babice, Southern Poland

“…Finally, the calcium carbonate recorded occasionally on the black surface of bricks is most likely related to the dissolution and leaching of lime-sand or cement-lime mortars binding the structural blocks and the karstification of the adjacent limestone blocks. It should be noted that calcite may also be linked to the carbonation process of hydrated calcium oxide Ca(OH) 2 present in bricks [83]. In a polluted atmosphere, calcium carbonate present on the brick surface may become a substrate in a reaction to form hydrated calcium sulphate, i.e., gypsum.…”

Crystallization Cycles in Masonry Walls: Experimental Technique to Develop Accelerated Aging on a Real Scale

“…4. Instruments like thermographic cameras and solid hygrometers, record temperature and moisture, aiding in identifying the origin or causes of the pathology (Cañola et al, 2020;Coletti et al, 2023;Erazo-Aux et al, 2022;Serna Moreno, 2016).…”

Climate Change Threats to Stone Cultural Heritage: State of the Art of Quantitative Damage Functions and New Challenges for a Sustainable Future

“…The presence of atmospheric CO 2 plays an important role in the weathering process and it is the cause of carbonate stone dissolution [7][8][9], while SO 2 can react with CaCO 3 to form gypsum (CaSO 4 •2H 2 O), causing the common decay pattern characterized by a succession of "black crusts" in sheltered areas and white colored areas on surfaces exposed to rainfall (washed areas) [3,10,11] (Figure 1a,b). The dissolved HNO 3 significantly raises carbonate solubility, increasing specific surface and stone porosity, thus widening the interface where surface interactions (and consequently deterioration) operate between the material and the surrounding environment [9,[12][13][14][15]. In environmental conditions where temperature can drop below freezing and where airborne salts (e.g., from sea spray) are present, strong decay occurs due to the overpressure generated in pores by the crystallization of ice and salts, respectively [9,16,17] (Figure 1c-e).…”