Evaluation of technical and gamma radiation shielding properties of sustainable ultra-high performance geopolymer concrete.

This study proposed to use barite-enhanced ultra-high performance geopolymer concrete (UHPGC) as the composite matrix to develop high-strength, cement-free, and sustainable radiation shielding materials. The physical properties, γ ray attenuation capacity, microstructure, and environmental and economic impacts of prepared barite-enhanced radiation shielding UHPGC were determined and compared with normal concrete and ultra-high performance concrete (UHPC). The combination of steel fibers and barite aggregate increased the density of UHPGC, thereby enhancing its γ ray attenuation capacity. Multi-scale γ ray shielding simulation results demonstrated that although thickness was the more decisive factor of γ ray attenuation capacity of composites, the enhancement of the shielding capacity of the material helps reduce the floor area and the cost of radiation shielding structure. The micro-analysis results revealed that barite-enhanced UHPGC exhibited compact microstructure and excellent interfacial performance. Furthermore, life cycle assessment results demonstrated that UHPGC was more suitable as a composite matrix than UHPC to develop sustainable and low-cost radiation shielding materials. [Display omitted] • Barite-based UHPGC was developed for the proposal of high-strength, cement-free and sustainable radiation shielding materials. • Compressive strength and flexural strength of developed barite-enhanced UHPGC exceeded 140 MPa and 15 MPa. • Compared with normal concrete, gamma ray shielding capacity of barite-enhanced UHPGC was enhanced 8.8 %. • Barite-enhanced UHPGC exhibited enormous ecological and environmental benefits compare with UHPC. • Barite-enhanced UHPGC is a promising radiation shielding material applied in nuclear power plants. [ABSTRACT FROM AUTHOR]