The Military Engineering Institute (IME), an army university in the city of Rio de Janeiro, found a way to cheapen the construction of highways in Brazil. The IME Soil Laboratory created a clay transformation process that permits its use in construction in the place of gravel.
According to the coordinator of the research, professor and colonel ílvaro Vieira, calcinated clay, as the product is called, may cost less than half of the price of gravel.
It may be used in the production of tarmac or as an input for concrete, used in the construction of bridges and buildings.
The study started eight years ago and was patented at the end of last year. So as to reach the final product, the clay is dampened, has the air removed and is compressed in an extrusion machine.
When it comes out, it is put out to dry naturally. After that, it goes into an oven at high temperature, between 800 and 1,000 degrees Celsius. At the end it is ground, like gravel, and may then be used in the production of concrete or asphalt.
According to Vieira, the product must be made out of clay with special chemical and physical properties, like that of the kaolinite family.
Calcinated clay is not yet made in commercial scale, but the production process has already been tested by ceramics company Cerâmica Ciframa, from the city of Santarém, in the northern Brazilian state of Pará.
The technology, however, is dominated and may be used by Brazilian or foreign companies under approval by the IME. “The technology may be used in any region of the world,” stated Vieira.
The intention of the researchers, at the beginning of the study, was to simplify and cheapen the cost of construction of highways in the Amazon region, where there is lack of stone.
The cubic meter of gravel in the Santarém region costs around US$ 40, whereas calcinated clay should cost around US$ 15 per cubic meter.
“Our interest is the development of the Amazon region, which is little reached by transport in Brazil,” stated the professor.
According to Vieira, the IME does not intend to have financial benefits from the technology. The patent was registered, according to the researcher, only to guarantee the continuation of the research.
Although the process is already ready for use, the university is studying new applications for the product. According to Vieira, during the tests, calcinated clay showed itself more resistant than the stone extracted, for example, at quarries in the state of Rio de Janeiro.
The study was developed by Vieira together with another IME professor, Luiz Antônio Silveira Lopes, from the Fortification and Construction Engineering department in the university’s Soil Laboratory.
A total of 12 people participated in the study since it was started, among them professors, students and technicians.
The IME offers graduation, master degrees and doctorates in engineering to civilian and military students. Every year a total of 100 civilian and 20 military students enter the institute.
The courses are free. Ten different engineering courses are offered in graduation, among them Electric, Electronic, Computer, Cartographic and Communications.
Military Engineering Institute (IME)
ANBA – Brazil-Arab News Agency