Axially Compressive Capacity Of Corroded High Strength Steel Columns And Failure Probability Analysis Of Corroded Steel Frames

As an important building material,steel is widely used in high-rise buildings,large-span structures and industrial plants.Corrosion is one of the main disasters of construction steel.How to scientifically evaluate the residual bearing capacity and deformation performance of corroded steel members and structures is one of the research hotspot of corrosion problem.At home and abroad,the stress and deformation properties of steel members with different yield strength and section under various working conditions have been tested and studied,and in this process,the evaluation index of corrosion degree has been gradually refined.However,the research is idealized and the differences between the corroded members are so large that the test results are often not reproducible,which loses the guiding significance to the engineering practice.In this paper,the method of finite element simulation and theoretical analysis is adopted to study the corrosion evaluation index of steel components and the axial compression performance after corrosion with high strength H steel column as the research object and axial compression as the research condition.On this basis,probability analysis method is used to predict the bearing capacity loss of components,and then the failure probability and failure location of the whole structure under different corrosion distributions and degrees are speculated.The main contents are as follows:(1)The shapes,width-depth ratios,arrangement patterns,distribution positions,pit depths,DOV,etc.of the pits were changed to study the maximum bearing capacity and the deformation development process of the components under different parameters,After this,the main influencing factors were determined and the preliminary change rules were obtained.(2)The variation rules of ultimate bearing capacity and deformation capacity with pit depth,DOV and pit distribution are analyzed.(3)Based on the simulation results,probability analysis method was used to establish the probability distribution model of random pitting distribution under different DOV conditions and the probability distribution model of component axial bearing capacity loss caused by random pitting size.(4)The probability distribution model of bearing capacity loss of the component under full working condition was established by using the frequency of working condition as the weight function,and the failure criteria of each component were solved iteratively,so as to obtain the failure probability of the structure.