Effect of carbon nanotubes on calcium carbonate/calcium silicate phase and morphology

The composition and microstructure of different CaCO3-Ca2SiO4-carbon nanotube composites have been studied. Materials have been characterized by X-ray diffraction (XRD), high resolution scanning electron microscopy (SEM), thermogravimetric/differential thermal analysis (TG/DTA), and Fourier-transform infrared (FTIR) spectroscopy. The morphology and structure of the inorganic systems are affected by the presence of multiwall carbon nanotubes (MWCNT) during the hydration processes and the nature of the MWCNT/SDS interface plays a role in the curing stages of the composite enhancing the growth of calcium silicate

Enhancing durability of concrete mixtures with supplementary cementitious materials: A study on organic acid corrosion and physical abrasion in pig farm environments

This study assessed concrete durability in pig farm environments, focusing on resistance to organic acid corrosion and physical abrasion. It used supplementary cementitious materials like silica fume (SF), coal fly ash (CFA), and bagasse fly ash (BFA) to improve concrete resilience. The research involved casting and testing concrete samples for compressive strength, acid corrosion resistance, abrasion resistance, and their combined effects. A custom apparatus simulated corrosion and abrasion cycles typical in pig farm flooring. Results showed that a combination of SF, CFA, and BFA significantly enhanced compressive strength, especially with extended curing. Additionally, these materials improved concrete's resistance to acid corrosion, physical abrasion, and their combined effects. The replacement of 30 wt% of cement with CFA and BFA in concrete significantly reduced mass loss due to acid corrosion to less than 10%, whereas the control mix exhibited a mass loss exceeding 24%. Additionally, concrete with 30 wt% CFA or BFA replacement exhibited a minimal combined mass loss, decreasing to less than 2.5% due to acid corrosion and physical abrasion, as opposed to the 16% observed in the control mixture