Banca de DEFESA: ABRAHAM RODOLPHE ABIODOUN OMORE

EVALUATION OF THE EFFICIENCY OF SURFACE TREATMENT OF MORTAR COATING WITH THE USE OF HARDENERS SURFACES

Coating mortar; Clay minerals; Pathological manifestations; Superficial
treatment; Surface hardeners.

The addition of clay minerals to coating mortars in Brazil has been reported since the
colonial period. During this time, in Salvador and the Metropolitan Region, there was a
predominance of the use of this type of mortar in buildings. However, the empiricism
adopted to establish the amount of clay minerals in the mixes and the lack of specific
normative criteria for mortar dosage, to date, has generated a significant number of
pathological problems in mortar coverings with the addition of clay minerals. Given this
context, it is necessary to research methods to solve the pathologies that occur in
mortar coatings. The objective of this study is to analyze the efficiency of surface
treatment with liquid surface hardeners applied to masonry panels produced in the
laboratory. To this end, a literature review was carried out in scientific databases
(Scopus, Web of Science, Engineering Village and Science Direct) on the topic, in
addition to the technical standards related to the study, which guided the preparation
of the project. Regarding the analysis, characterization tests were carried out on both
the materials used to obtain the mortar (cement, sand and clay mineral) and the
ceramic blocks. Furthermore, a mortar dosage study containing clay additions was
carried out, from which a reference mortar and two different groups with excess clay
material were defined. Next, four masonry panels were made, one was used as a
reference and hardeners were applied to the others. Regarding mechanical properties,
the coatings were evaluated based on tensile adhesion, surface adhesion, scratch and
impact resistance tests. Regarding microstructural evaluation, analyzes were carried
out using optical microscopy, scanning electron microscope (SEM), in addition to X-ray
diffraction (XRD). It was concluded that each product used presented a different
performance, but in all cases the application of surface hardener promoted an increase
in the adhesion resistance to surface traction and contributed to the partial
waterproofing of the coating system, making it difficult for water to penetrate into the
surface. substrate.