圆钢管型钢再生混凝土短柱偏压力学性能退化研究

为研究圆钢管型钢再生混凝土短柱在偏压荷载作用下的性能退化,进行了10个短柱试件偏心受压试验。主要分析了再生粗骨料取代率、圆钢管径厚比、型钢配钢率和偏心距等参数对试件的荷载-挠度曲线、变形能力、刚度退化及耗能能力的影响。结果表明:该短柱具有较高的承载力和抗弯刚度;与普通混凝土相比,取代率的增加对短柱的承载力和变形是不利的,试件的挠度变形随着取代率的增加而增大,再生粗骨料取代率为100%的试件偏压承载力降低了8.98%,试件刚度退化速率随着取代率的增加而加快,耗能能力逐渐降低;试件的挠度变形随着圆钢管径厚比的增大或型钢配钢率的减小而增大;试件刚度退化速率随圆钢管壁厚、型钢配钢率的增加逐渐变慢,耗能能力增强;另外,偏心距对试件偏压性能影响较为显著,随着偏心距的增大,试件刚度退化和承载力降低更加明显。

Performance degradation of RAC filled circular steel tube-profile short columns under eccentric compression

In order to study the performance degradation of recycled aggregate concrete(RAC)filled circular steel tube-profile short columns under eccentric compression loading,the eccentric compressive test of 10 short columns is carried out.Influence of recycled coarse aggregate(RCA)replacement percentage,diameter-to-thickness ratio of steel tube,steel ratio and eccentricity on the load-deflection curves,deformation ability,stiffness degradation and energy dissipation capacity of the specimens are mainly analyzed.Results show that the short columns have high bearing capacity and bending stiffness.Comparing with ordinary concrete,the increase of replacement percentage is adverse to the bearing capacity and deformation of short columns.The deflection of specimens increases with the increase of RCA replacement percentage,and the eccentric bearing capacity of specimens with 100%replacement ratio of recycled coarse aggregate decreased by 8.98%.The stiffness degradation rate of specimens accelerated with the increase of replacement percentage,and the energy dissipation capacity gradually reduced.The deflection of the specimens increase with the increase of diameter-to-thickness ratio of circular steel tube or the decrease of the section steel ratio.The stiffness degradation rate of the specimens gradually slowed with the increase of wall thickness of circular steel tube and section steel ratio,and the energy dissipation capacity increases at the same time.In addition,the eccentricity had an obvious effect on the eccentric compression performance of specimens,which shows that with the increase of eccentricity,the decrease of the stiffness degradation and bearing capacity of specimens became more serious.The research results can provide reference for the research and application of this kind of the columns.