Objective:

This research aims to reduce Portland cement contents in concrete by using small amounts of additives as an Industry-University partnership strategy towards a circular economy of concrete in Medellín, Colombia.

Methodology:

Using a multilevel factorial statistical model, mortar mixes were prepared with two different super-plasticizers: additive 1, based on policarboxilate; and additive 2 based on naftalene. Samples were evaluated at 7, 14, 21, and 28 days of curing via compression tests. The aforementioned model was implemented in order to study the influence of additives on the cement mortar mix. The microstructure was analyzed with x-ray diffraction and scanning electron microscopy.

Results:

The results revealed that both additives improved workability. Additive 1 showed better overall properties, which is why this research focused on it.

Conclusions:

Additive 1 (based on polycarboxylate) reduces the water-to-cement from 0,485 to 0,38, which corresponds with a cement reduction of 7,3% and a water reduction of 27,3%.

Financing:

Composites research group - Universidad de Antioquia, CONASFALTOS.