摘要
厚型钢结构防火涂层因其耐火性好、性能稳定而成为最常用的防火保护形式之一,但厚型防火涂层易在地震和冲击等作用下发生破损和脱落,这将影响钢结构的抗火性能。为了认识厚型钢结构防火涂层的破损模式,本文对涂有厚型防火涂料的钢板件进行了纯弯荷载试验,运用有限元分析软件AN SY S对试验全过程进行了模拟分析,并与试验结果相对比。结果表明:受弯构件压区涂层的破损模式主要为涂层-钢板界面破损,拉区涂层的破损模式与涂层厚度有关,当涂层厚度较薄时,主要为涂层内部拉裂,涂层厚度较厚时,主要为涂层-钢板界面破损;涂层厚度越厚,界面破损出现得越早;若在涂层上贴置应变片,会使涂层的界面裂缝和横向裂缝提早出现。
Thick fireproof coatings are widely adopted for their good fire resistance performance.Thick fireproof coatings would be easily damaged in loads such as earthquake and impact,which may leads to a considerable reduction of fire resistance.Hence,in this paper,a series of experiments were conducted to investigate the damage mode of thick fireproof coatings for steel plates under monotonic bending loading.The corresponding finite element models were established to analyze the whole process and compare with experiment results.The results show that for the case of bending loading(on compression side),damage begins with shear debonding at the ends of the interface and the failure mode is the peeling off of the whole coatings.But on tension side,normal debonding occurs at the ends of the interface followed by the transverse tensile crack in the coating.And it is found that the thicker the coating is,the earlier the debonding at the interface occurs.The cracks in the interface and the coatings appear earlier when there is strain gauge installed on the coatings.
引文
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