Fire Resistance Performance Analysis of Bolt-connected Fabricated Beam-Column Joints
The fire resistance performance of a new type of bolt-connected fabricated beam-column joint is studied,and the stress distribution and failure mode of the bolted-connected fabricated beam-column joints are analyzed,thus it provides a theoretical basis for fire resistance design of bolt-connected fabricated beam-column joints in this paper.The finite element software ABAQUS is used to establish the model of bolt-connected fabricated beam-column joints,and the sequential thermodynamic coupling method is used to conduct numerical simulation analysis of the beam-column joints under different working conditions,then the influence of beam end load ratio,concrete protective layer thickness and fire exposure case on the fire resistance performance of bolt-connected fabricated beam-column joints are discussed.When the thickness of concrete protective layer is increased from 25 mm to 30 mm,the fire resistance limit of the joint increases slightly,when the thickness of concrete protective layer is increased from 30 mm to 35 mm,the fire resistance limit of the joint increases significantly;Compared with four-side fire,the displacement of the beam end of the joint in three-side fire condition is more obviously affected by the load ratio of beam end and the thickness of concrete protective layer.When the beam end load ratio is reduced from 0.7 to 0.5,the fire resistance limit of the joint is increased by 61％～68％;when the thickness of concrete protective layer is increased from 25 mm to 35 mm,the fire resistance limit of the joint is increased by 10％～20％.The fire resistance limit of the joint is mainly affected by the fire resistance limit of beams in the node region;when beam end load ratio increases,the fire resistance limit of the joint decreases.In addition,the fire resistance limit of the joint in three-side fire condition is obviously greater than that in four-side fire condition.Therefore,the fire isolation treatment on the upper surface of the beams can greatly improve the fire resistance limit of the joint.
prefabricated beam-column jointsfire resistancefire resistance limitfinite element analysis
万方数据
维普
