Study On Mechanical Property Of High-Strength Concrete Axial Compression Column At High Temperature

In this thesis, firstly, the development of structural fire resistance and present situation of fire-resistance research on high-strength concrete (HSC) structures are introduced. The feasibility of applying FEA method is proposed and the main tusk in this dissertation is illustrated referring to the case, that all the study almost is basing on experiments, so that a simple method is obtained in actual engineering.Secondly, the temperature distribution in column must be analyzed before analyzing mechanical property of HSC column at high temperature, so the thesis applies load steps of ANSYS software to analyze transient temperature field on the section, When the temperature field is analyzed, finite element grids are divided in space field and finite difference grids are divided in time field. The computing results are in good agreement with the test data.Thirdly, the commonly theory of using FEA analysis is discussed. Utilizing FEA program ANSYS the author models HSC axial compression column, calculates load bearing capacity and deformation of HSC column at different temperature, and compiles temperature-deformation curve, load-deformation curve and stress distribution in section. It indicated that the mathematical model is capable of predicting the fire resistance through comparing with experiment results. Besides, the variables summarized and studied in this paper show temperature and strength of concrete have larger influence, on the fire resistance of the columns, then the amount of steel, but the influenceof hoop amount is insignificant. At last, on the basis of analysis result the conclusion is drawn and the useful recommendation and perspectives are put forward.