The innovation, patented by the team of scientists of the Faculty of Civil Engineering, contributes to the solution of ecological problems: by reducing the amount of the concrete, they also reduce the amount of its main component – the cement. The experiments proved that cement industry produces even five per cent of carbon dioxide (CO2) worldwide. Thus, the production of concrete would also reduce the emission of CO2.
"The development and testing of the inserts started, while collaborating with the company, interested in the practical implementation of this innovation. We carried out various experiments and application research, prepared special methodology of calculation for designers. We planned the production of the inserts from secondary raw materials – second hand plastic, collected in Lithuania and specially prefabricated. Therefore, waste will be "preserved" on the construction sites instead of the dumps", - said Prof. Dr. Juozas Valivonis, Head of the Department of Reinforced Concrete and Masonry Structures of the Faculty of Civil Engineering at VGTU.
The plastic inserts, created by the researchers in Lithuania, from the similar products, produced elsewhere in the world, differ in their form – the form is close to the cube, with sets for attachment the reinforcement elements, and with special grooves for prevention the emergence of air voids in the concrete, next to the insert. The inserts are larger, thus, they save more building materials. The tests, carried out by the scientists of VGTU Civil Engineering Research Centre showed that plastic inserts in the concrete slabs do not alter their mechanical characteristics, therefore, they can use the inserts in the construction industry. At the Mobile Applications laboratory, the researchers tested thirty different slabs, changing the number of inserts and layouts.
There are two parts of the insert, thus, no big labour costs or long preparation is necessary for their assemblage. Due to the form characteristics, they can simply pile the inserts on each other and save space during storage, as well as easily transport them to the construction site. Slabs with inserts can be used for setting up building's overlays or reinforced concrete walls.