Seismic Reliability Analysis Of Concrete Columns

The eccentrically loaded concrete columns is the main load-bearing component, the failure of which will have a significant impact on the safety of the entire structure. Therefore, it is necessary to adopt appropriate methods to analyse its reliability. In this paper, in the way of preparing non-linear numerical analysis procedures by matlab, Monte-Carlo simulation method is used to calculate the reliability of eccentrically loaded concrete column under the usual dead load, live load and horizontal seismic action(both the resistance and action effects are obtained by Monte-Carlo simulation).The major difficulty in reliability analysis of the eccentrically loaded concrete columns is the correlation between the axial load and the bending moments. Thus, the random nature of the load eccentricity must be considered when we analyze the reliability of the eccentrically loaded concrete columns.The results show that the correlation of load effects is, in fact, related to the effects of the random variables eG(eccentricity of the dead load) and eQ(eccentricity of the live load) on the external bending moment.The failure of the eccentrically loaded concrete columns has something to do with load. If load path changes, both the ultimate bearing capacity and the failure mode will change for the columns with same concrete strength, same reinforcement strength and quantity, and same section features. When load effect path and statistical characterastics of load effect are preset,the sample values of dead load and live load effect can be obtained by random sampling, and the load correlation of eccentrically loaded concrete column can be analysed by Monte-Carlo simulation method conveniently, which gives an easy way for the reliability calculation of eccentrically loaded concrete column.This paper analyzes the changes of reliable indicator for eccentrically loaded reinforced concrete column and eccentrically loaded steel reinforced concrete column with the different ratio of load effects p and eccentricity k. Meanwhile, by means of analyzing and summarizing the statistical characteristics of the seismic (we only consider the horizontal earthquake) and the gravity load, we carry out the seismic reliability analysis between the eccentrically loaded reinforced concrete column and the eccentrically loaded steel reinforced concrete column, and discuss the influence of the reliability of concrete columns in some respects, such as the correlation of load,the section size, the concrete strength, the reinforcement ratio, the cross-section steel ratio and the ratio of load effect.