Mechanical performance and healing process improvement of cement-coir pith particle composites by accelerated carbonation

The accelerated carbonation during the early cure age is a process used to improve the physical and mechanical properties of cement-based composites. In this work, cement-based composites with coir pith particles addition were subjected to the accelerated carbonation process during the first 48 hours of cure in a rich CO2 environment. After curing, the samples were dried and subjected to curing conditions until saturated at 28 days. Thermogravimetric analyses, scanning electron microscopy (SEM) and X-ray diffraction patterns were used to analyze the impact of accelerated carbonation during the early cure age in cement-coir pith composite. The results of the physical properties show an increase in bulk density and surface density of the carbonated samples, as well as reduced water absorption. The reduction of the Ca(OH)2 resulting in the increasing of CaCO3 content was observed by thermogravimetric analysis. The carbonated samples had a 41% increase in compression strength and 28% in the modulus of rupture as compared to non-carbonate samples. The results showed the potential of the accelerated carbonation cure process in cement-based composites with vegetable coconut waste addition. Keywords: Accelerated carbonation, mechanical properties, thermal analysis, cement-based composites, coir pith particle