Evaluation of reinforced concrete structural durability in the post-occupation phase - A case study in Novo Hamburgo/RS

Abstract

Researches on building performance have been developed over time. The Brazilian Performance Standard -NBR 15575 -deals with the issues of durability applied to residential buildings, establishing criteria and parameters to classify the systems into minimum, intermediate and higher performance levels. In relation to the service life, studies are also associated with the building's structural durability, in which the technical specifications and quality of materials, construction systems, building process, use and maintenance of the building are important factors for better performance. In order to evaluate the structural durability over the years, a case study was conducted in a building designed to meet the higher level established in the Brazilian Performance Standard, with service life of 75 years in the structural project, through the non-destructive surface hardness of concrete test by using a Schmidt hammer and semi-destructive carbonation tests. The superficial hardness test was conducted on a concrete column following the procedures of NBR 7584, while the carbonation samples were collected in 3 concrete columns in which a phenolphthalein solution was sprayed to observe the alkalinity of the samples. For all tests, three different heights were considered. The concrete testing hammer indicated an average surface hardness of approximately 50 MPa, and for carbonation tests, it was noted that the concrete was not carbonated at a depth of 5mm. So, the criteria of service life could be considered attended.

Proposal of a method for service life prediction of a concrete structure: a case study

“…It is possible to verify through the results presented in Table 2, that the compressive strength of the surface of the precast element indicates values over 50 MPa, which initially suggest some characteristics of the analyzed structure. According to Bueno et al (2019), the results presented above are between an intermediate and a high average of compressive strength and a lower deviation was obtained, since the structure elements in that study were not precasted.…”

Application of the GUT technique in pathological manifestations in reinforced concrete structures and their corrections

“…In their research they verified that steel corrosion in the structures is one of the main flaws found. Besides that, Helene (2002), Angst (2018) and Bueno et al (2019) also affirm this predominant incidence of steel corrosion as the main manifestation pathological in reinforced concrete structures.…”

Parametric Study to Maximize the Useful Life of Reinforced Concrete Columns

“…Currently, the limited availability of resources, the need for more sustainable buildings and the number of reinforced concrete constructions with pathological manifestations make studies on durability increasingly important (Gardner et al, 2018). In reinforced concrete structures the most common pathology is corrosion (Bueno et al, 2019). It can be detected mainly through surface stains and cracks, degradations that compromise structural safety.…”