Investigating crumb rubber-modified geopolymer composites derived from steel slag for enhanced thermal performance

Thermal performance of building materials is often improved by introducing air voids through foaming. However, this typically results in a reduction in compressive strength. To address this issue, an experimental study was conducted to develop thermally efficient geopolymer blocks using three grades of crumb rubber (CR), without compromising compressive strength. Tests such as compressive strength, tensile strength, thermal conductivity, water absorption, and porosity were carried out to assess the performance of these blocks in comparison to conventional geopolymer blocks. The CR-incorporated geopolymer blocks demonstrated low thermal conductivity, ranging from 0.63 to 0.43 W/mK, along with a reduced environmental impact and carbon footprint. Importantly, they exhibited high compressive strength, ranging from 25 to 52 MPa, which exceeds the required strength for first-class bricks (12 MPa). A computational conjugate heat transfer analysis was also carried out to evaluate the strength of heat transferred through the solid media to the internal fluid media. It contributes to the advancement of environmentally conscious building materials, emphasizing the potential benefits of crumb rubber-incorporated geopolymer composites as a novel material for building construction purpose.