Characterization of bedding mortar from the Mosteirinho da Irmandade de São Francisco, at Paudalho, Pernambuco, Brazil

Abstract

This work presents the study carried out at Mosteirinho da Irmandade de São Francisco, an abandoned Franciscan monastery in Paudalho, Pernambuco, in the northeast of Brazil. Bedding mortars found in the building were characterized and compared to sand samples collected near the building in order to better understand the materials used in its construction. Mortar samples went through granulometric analysis, thermogravimetric analysis, X-ray fluorescence (XRF), X-ray diffractometry (XRD) and microscopy, including petrographic analysis and scanning electron microscopy (SEM). Sand samples went through granulometric analysis, petrographic classification of the grains and petrographic analysis. From the results, it is possible to conclude that the masonry mortar of the internal walls was made with clay, without the presence of lime binder, while the external wall contains a binder made of clay and lime. The sand collected near the building contains shells fragments and has features similar to the mortar aggregate found in only one of the analyzed samples. That suggests that sand from the region may have been used in at least one phase of construction.