The subject of concrete formwork, always on highlight, was a recurring topic in the seminars during last year's Concrete Show.
Representing a great evolution for civil construction, the system provides a series of advantages and can be used in the construction of single-story houses, townhouses, buildings, and tall buildings, with the latter perhaps being a barely known reality.
Augusto Pedreira de Freitas, Civil Engineer, Managing Partner of Pedreira Ônix, and Advisor to the Brazilian Association of Structural Engineering and Consulting (Abece) took part in the Seminar “Concrete Formwork for Tall Buildings” with the subject “The competitiveness of the System - Interface Architecture versus Structure versus Installations".
Read on to find out the main points addressed by Pedreira de Freitas during the seminar. Enjoy!
The quest for standards in civil construction
Although there is a constant quest for standards in the area of civil construction, Freitas states that they may be a somewhat complicated topic to address.
“When we talk about standards in civil construction, there is an image that comes to mind: a little industry that always does the same thing and has to make a thousand units of the same thing. This is just not true. This is a very outdated perspective”, the guest stated.
According to Freitas, “civil construction has evolved a lot and has many industrialized processes”. These processes even have different degrees of industrialization.
“I need to analyze the degree of industrialization I have for my development. What we can't do is turn a blind eye to industrialization and take a fully artisanal approach to things that could be done in a more rational manner”, he pointed out.
The path of the automobile industry
To provide examples of the quest for patterns, engineer Freitas offered an analogy with the automobile industry. At first, cars were pretty much the same. Over the years, however, there has been an evolution.
“What did they do? They looked for patterns, where you have a section that is standardized and repeats, and the rest moves according to a rule”, showed Freitas.
However, this rule cannot be created on a whim by the architect or engineer responsible for the work – it needs to be in accordance with what has already been studied. As an example, we currently have ABNT NBR 15575, which refers to the performance of residential buildings.
Concrete formwork system and performance standard
Regarding the concrete formwork system, Freitas was categorical when stating that “the greater the cover, the greater the durability. With the new standard, we will be able to have an 18-centimeter wall with a centered screen, an incredible length, and an incredible durability”.
The expert also pointed out that the slabs are analyzed the same way as a conventional system, but since we tend to have fewer walls in tall buildings, better use is made of the thickness required for acoustics.
As for the walls, apartment divisions between rooms should be avoided, as they may require more care than just the wall itself. “It may seem strange to avoid dividing rooms with a concrete wall, but it's better for those divisions to be made of drywall”, he suggested.
To close out the presentation, Augusto Pedreira de Freitas presented some examples of tall buildings made of concrete formwork walls. “For a very tall building, I need to have a concrete wall”.
One of the examples he brought involved buildings built by Pedreira Ônix in the city of Balneário Camboriú, in Santa Catarina, which are 17.4 (H=165m/ L=9.5m).
Learn more about the Concrete Show - the constructive chain event.
