提高混凝土和CFST柱的耐火性.pdf

1、WU,BoSouth China University of TechnologyAugust 13,2024,SingaporeImprovement of Fire Resistance ofCFST&RC ColumnsOutlineResearch background1Fire resistance of CFST columns with internal stirrups(IS)2Compression behavior of CFST columns with IS3Seismic performance of CFST columns with IS4Design code&

2、summary65Fire resistance of RC columns with external stirrups(ES)CFST columns:superior structural behaviors and easy of construction,but bare steeltube leads to poor fire resistance,and the use of fire protection isnecessary.Engineering applicationConstruction offireproof layersThin fire-retardant c

3、oatingThick fire-retardant coatingl High cost of fire-retardant coatingsl Uncertainty of thelifecycle effectivenessof fireproof layersl Significant increase in steel usage and high construction costsl Construction difficulties at beam-column joints1 Chabot M,et al.NRC-CNRC internal report,No.628,199

4、2.3 Romero ML,et al.Eng.Struct.,2015,99:536-545.5 Neuenschwander M,et al.J.Struct.Eng.,2017,143(4):04016211.2 Lu H,et al.Fire Safety J.,2010,45(2):106-115.4 Zhu SY,et al.J.Shanghai Normal Univ.,2014,43(3):319-322.Reinforcementsdouble steel tubeSteel profileSteel coreHollow steel tubeInstalling steel

5、 bars or adding steel components inside the steel tubesl Exsiting methodsWith the same total steel consumption,splittingthethicker steel tube into a thinner one andsteel stirrups or spiral inside,and a certaindistance being left in betweenl Behaviors at room temperature(e.g.,compression,seismic,etc.

6、)are generally comparable to those oftraditional CFST columnsl Significantly enhanced fire resistancel Significant reduction in the overall cost overfire-retardant coatingsl Fire resistance performance does not deteriorateduring the structural serving lifel Easy of constructionCFST column with inter