Durable Spray-applied Fire-resistive Material for Enhanced Safety of Steel Structures.

Spray-applied fire-resistive material;Engineered Cementitious Composites;Fire safety;Civil and Environmental Engineering;Engineering;Civil Engineering

Zhang, QianJeffers, Ann E. ;

University of Michigan

关键词: Spray-applied fire-resistive material;    Engineered Cementitious Composites;    Fire safety;    Civil and Environmental Engineering;    Engineering;    Civil Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/113583/maplezq_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Although spray-applied fire-resistive materials (SFRM) are the most commonly used passive fire protection for steel structures, its performance is often called into question due to their unsatisfactory durability performance. The inherent brittleness, low strength and poor bond with steel lead to delamination and partial loss of fire protection even under service loads, significantly lowering the structural fire resistance. This could be further exaggerated under multi-hazards, such as post-earthquake and post-impact fires, greatly endangering the fire safety of steel structures. To address this critical issue, a new ductile cementitious SFRM, namely spray-applied fire-resistive engineered cementitious composite (SFR-ECC), has been developed that overcomes the aforementioned problem. Following a parallel design process, SFR-ECC has been developed to satisfy multiple performance targets in one material, including low thermal conductivity, high tensile ductility, high adhesion to steel and sprayability. The resultant material possesses tensile strength, strain capacity, interfacial adhesive energy of 1-2 orders of magnitude higher than the conventional SFRM, yet possesses similar thermal conductivity and sprayability, providing a durable alternative to conventional SFRM. SFR-ECC is also found to exhibit ductile cellular behavior under compression, further enhancing its energy absorption capacity.The micromechanical and microstructural mechanisms underlying the unique tensile and compressive behavior of SFR-ECC are studied. The material macro- and micro-mechanical behavior under high loading rates have also been investigated. SFR-ECC is found to maintain high tensile ductility under high rate loadings, ensuring its performance under earthquake and impact loads.