A fireproof insulation block with three-dimensional pore structure fabricated using alkali activated steel slag

• Published in: Construction & building materials Vol. 425; p. 136134
• Main Authors: Tang, Xue, Zhao, Hengze, Ding, Hongling, Qi, Yipei, Li, Ye
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 26.04.2024
• Subjects: Compressive strength; Fireproof insulation block; Porosity; Steel slag; Thermal conductivity; Thermal conductivity; Compressive strength; Porosity; Fireproof insulation block; Steel slag
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2024.136134

In an effort to fully harness the potential of steel slag, it has been employed in the production of fire-resistant insulation blocks. A comprehensive investigation was conducted to examine the influence of sodium silicate modulus, water addition, hydrogen peroxide addition, and curing temperature on various properties such as porosity, apparent density, thermal conductivity, and compressive strength of the blocks. The results reveal that the prepared fireproof insulation block possesses a porosity of 89.6%, an apparent density of 0.334 g/cm3, a thermal conductivity of 0.177 W/(m∙K), and a compressive strength of 0.12 MPa, achieved with preparation parameters including a sodium silicate modulus of 1.5, a water content of 20%, a foaming agent addition of 4%, and a curing temperature of 50 °C. The relationship between the thermal conductivity and porosity can be accurately predicted using the NEMT model. Furthermore, to further decrease the thermal conductivity of the material, it is possible to reduce both the size and connectivity of the pores present within it. This research offers insights and avenues for the expanded utilization of steel slag in the development of building materials. •100% of steel slag was employed to prepare fire-resistant insulation blocks.•The block has an 89.6% porosity and a thermal conductivity of 0.177 W/(m∙K).•NEMT model can be used to predict the thermal conductivity of this material.•Reducing the apparent size of pores can enhance thermal conductivity.•Reducing the connectivity between pores can enhance thermal conductivity.