Research On Bearing Performance Of Corroded Fastener Steel Pipe Scaffolding System

The steel pipe scaffolding system used in actual engineering often has different degrees of corrosion.Corrosion leads to loss of steel pipe section,mechanical properties of steel,degradation of restraint performance of steel pipe-fastener joints,reduction of stability of vertical bars,and decline of structural bearing capacity.It has a serious impact on the safety of the scaffolding system.Therefore,systematic study of the bearing performance of rust-fastened steel pipe scaffolding system can provide the necessary theoretical basis and technical support for construction safety control.In this paper,the method of outdoor periodic spraying of salt spray is used to accelerate the corrosion of steel pipes and fasteners,and the degree of weight loss is used to characterize the corrosion degree of the test pieces.The surface characteristics and mechanical properties of steel pipes with different degrees of corrosion were tested,and the corresponding relationship between surface characteristic parameters,mechanical indexes and corrosion rate was obtained.The bending moment-rotation angle and load-slip test of corroded steel pipe-fastener joints were analyzed.The influence of corrosion of steel pipe and corrosion of fasteners on the torsional behavior and anti-sliding performance of joints was established.The constitutive calculation model of steel pipe-fastener joints considering corrosion was established.The axial stability test of corroded steel pipes was used to analyze the corrosion poles.The influence law of stability and the calculation model of the axial stability of corroded steel pipe were established.Through the bearing capacity test of corroded fastener-type steel tube unit frame,the influence law of corrosion on the bearing capacity of the unit frame is analyzed.The same finite element model is established and compared with the test results to verify the validity of the finite element model.The finite element analysis model of single-row scaffolding and double-row scaffolding with different degrees of corrosion was established.The influence of corrosion on the bearing performance of single-row scaffolding and double-row scaffolding was analyzed.The calculation model of the bearing performance of rust single and double-row scaffolding was established.The bearing capacity test of the full-size support frame of the fastener-type steel tube was carried out.The validity of the finite element analysis model was verified by comparing the finite element analysis and the test results.The finite element model of the full-frame support frame with different degrees of corrosion was established,and the corrosion was analyzed.The influence law of the bearing capacity of the support frame.