Development and validation of an innovative Hybrid Laminate Material for the blast and fire protection of structures

This study presents the development of a novel Hybrid Laminate Material (HLM), particularly a dual-layered system combining an Ultra High Performance Fiber Reinforced Concrete (UHPFRC) and a Fire Resistant Geopolymer (FRG). The novel material is engineered to provide blast and impact as well as fire resistance, seeking to address the critical challenge of explosive spalling of concrete under high and rapidly rising temperatures while preserving structural integrity to withstand blast and impact loads. The FRG layer composition is optimized for environmental friendliness and cost, while assuring the formation of refractory phases at high temperatures to ensure adequate resistance to extreme temperatures. In parallel, a blast and impact-resistant UHPFRC layer is further optimized, aiming to provide exceptional compressive and flexural strength while minimizing fiber content and cost. The results highlight the development of a promising HLM that offers an environmentally friendly, cost-effective solution for enhancing the safety and resilience of critical infrastructure, incorporating robust, multifunctional building materials that can resist blast, impact, and endure extreme thermal conditions. The two layers demonstrate excellent results in their respective functions. The developed FRG successfully maintained its compressive strength while withstanding temperatures up to 1050 °C. Furthermore, an environmentally friendlier UHPFRC was designed, including 2% steel and 1% Polyvinyl Alcohol (PVA) fibers, without sacrificing the capacity to withstand blast and impact.