Fire resistance of post-earthquake steel beams insulated with a novel fire-resistive coating- FR-ECC

• Published in: Engineering structures 2021-11, Vol.246, p.112887, Article 112887
• Main Authors: Cai, Zi-wei, Yu, Jiang-tao, Tian, Li-kang, Liu, Fei-chi, Yu, Ke-quan
• Format: Article
• Language: English
• Subjects: Coatings; Cyclic loads; Ductility; Earthquake damage; Earthquake resistance; Earthquakes; Fire damage; Fire exposure; Fire resistance; Fire resistant materials; Fire-resistive engineered cementitious composites (FR-ECC); Fireproof coating; Fireproofing; Load resistance; Mechanical properties; Post-earthquake fire; Seismic activity; Steel beam; Steel beams; Steel structures; Substrates; Temperature distribution; Vertical distribution
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2021.112887

•FR-ECC owns large strain capacity up to 8% and micro cracks with crack width of 100 μm;•FR-ECC significantly increases the compatibility between fireproof coating and steel substrate;•FR-ECC significantly increases the fire-resistance limit of steel beams. Cementitious fire-resistive materials (CFRM) of steel structures, though widely used, feature several notable disadvantages, such as low mechanical properties, susceptible to crack and delamination from the steel substrate, which reduces the resilience of steel structures. A novel ultra-high ductility fire-resistive engineered cementitious composites (FR-ECC) was developed to address those advantages. The fire resistance of post-earthquake steel beams insulated with FR-ECC was investigated. Eight steel beams with the protection of CFRM, FR-ECC and FR-ECC matrix (without fiber) were designed, among which five beams were pre-damaged by reversed cyclic loading. The damage of fireproof coatings and the hysteretic behavior of steel beams after cyclic loading were evaluated before fire exposure. The vertical displacement, the temperature distribution of steel beams and the damage of fireproof coatings under fire exposure were obtained. The FR-ECC demonstrated milder damage than those of FR-ECC matrix and CFRM after cyclic loading. The fire-resistance test results further revealed a more excellent fire-protection performance of FR-ECC as a novel fireproof material. The advantages of the newly developed fireproof coating FR-ECC have been experimentally proved, which laid the foundation for its future application.