Development of breathable and moisture-absorbing cement pastes incorporating diatomite clay

The purpose of the project is to explore the variation in the ratio of diatomite clay to cement and its impact on the mechanical strength, moisture storage capacity, and microstructural characteristics of cement pastes, aiming to achieve positive performance in environmentally friendly construction. The cement pastes were made using diatomite clay and cement mixings of 50%:50% and 80%:20% ratios, and a water-to-cement ratio of 1.0–1.3. The obtained products were analyzed at physico-chemical characterization, including Field Emission Scanning Electron Microscopy (FESEM), Thermogravimetric Analysis (TGA), Modulus of Rupture (MOR), X-ray Diffraction (XRD), and water absorption. A mixture of diatomite clay to cement of 50:50 and a water to cement ratio of 1:1 produced desirable mechanical strength, with XRD findings showing it comprised a high percentage of tricalcium silicate (C3S) and dicalcium silicate (C2S). On the other hand, the higher moisture storage was encountered in the 80:20 ratio, but with water-to-cement ratios of 1.0 to 1.3, as its surface area and porosity were highest according to FE-SEM images. These results shed light on how diatomite clay-cement composite material can be shaped to have greater mechanical and moisture management strength to make it applicable in building materials with higher environmental performance over buildings and safer conditions.