Enhancing physical-thermal-mechanical properties of fired clay bricks by eggshell as a bio-filler and flux

Fired clay bio-bricks were prepared by adding eggshell as a bio-filler and flux into earthenware clay compounds via an extrusion process. In this study, the suiTab. conditions for clay bricks preparation were firing at 1000?C for a period of 5 h. Adding 20 wt% eggshell powder into the clay brick yielded good physical-mechanical-thermal properties: high compressive strength and hardness, low thermal expansion coefficient, and low water absorption. The measured compressive strength, hardness, and refractory water absorption were 7.0 MPa, 6.0 HV, and less than 15 wt%, respectively. The obtained clay brick with the eggshell powder added as shown here is potential for uses as bricks for construction and thermal insulation.