Argamassas históricas de Belém do Pará.

Abstract

The city of Belém, northern Brazil, known as the metropolis of the Amazon, was established on the banks of the Guajará Bay on January 12, 1616, with the denomination of Nossa Senhora de Belém do Grão-Pará, capital of the Grão-Pará province, now the state of Pará. Currently, Belém still has layers of lime mortar on its colonial and imperial buildings, which protect the secular structures and provide evidence of how this material was produced early in its history. Over the years, the deteriorating aspects identified in lime mortars, which damage both aesthetics and functionality, are related to the humidity, saline efflorescence, biological colonization, and/or anthropic actions. Once deteriorated, mortars require maintenance, consolidation, or replacement, which are difficult procedures that can lead to the use of inappropriate materials. Therefore, a good collect and characterization strategies of the original material is necessary for the restoration of historical monuments, because in studies focused on restoration science, the intervention strategy needs to include the use of building materials compatible with the original materials. Thus, the main objective of this doctoral thesis is to determine the characteristics and properties of historical mortars in Belém do Pará from the 18th and 19th centuries, as well as to propose a restoration mortars compatible with the historic mortars, which using industrial waste from Amazon Region. Therefore, this thesis was structured in three independent and complementary thematic articles, which addresses the topic of the historical mortars of Belém do Pará, since their characterization until the proposal of restoration mortars: 1) Investigation of the historical mortar of Belém do Pará, Northern Brazil; 2) How to estimate the binder: aggregate ratio from aerial lime-based historical mortars for restoration? and; 3) The use of industrial waste of the Amazon region in lime-metakaolin restoration mortars: compatibility assessment. Thus, the physical, chemical and mineralogical characteristics were determined, as well as the physical and mechanical properties of the historical material and the restoration material. The results of the historical mortars characterization pointing their main components, their functions and raw materials, besides indicating the analytical techniques used for binder: aggregate ratio quantification, which obtained good accuracy and reliability in your results. Moreover, the results show a wide range of characteristics and properties obtained through restoration mortars, which can serve as a benchmark for other studies or even for practical applications in historic masonry. Therefore, it was possible to identify the restoration mortars most compatible with the historical mortars of Belém do Pará, Northern Brazil.