圆钢管约束钢骨高强混凝土短柱轴压力学性能

Behavior of axially compressed circular tubed steel reinforced concrete(CTSRC) stub columns

进行了12个圆钢管约束钢骨高强混凝土短柱和2个钢骨高强混凝土对比试件的轴压力学性能试验研究,试验的主要参数为钢管径厚比(70,100)和钢管屈服强度(Q235和Q345)。试验结果表明,圆钢管约束钢骨高强混凝土柱中被分隔钢管的高度对构件的轴压承载力和延性无明显影响。钢管的径厚比对圆钢管约束钢骨高强混凝土轴压短柱的延性无明显影响;随钢管屈服强度的提高,构件的轴压承载力提高,但钢管屈服强度对轴压短柱的延性无明显影响。相同用钢量条件下,圆钢管约束钢骨高强混凝土短柱的轴压承载力明显高于钢骨高强混凝土柱。对钢管的应力分析结果表明,圆钢管约束钢骨高强混凝土轴压短柱的峰值荷载点对应于钢管的屈服点。根据试验结果和钢管的应力分析结果建立了圆钢管约束钢骨高强混凝土短柱的轴压承载力公式,提出了设计建议。

The behavior of 12 circular tubed steel reinforced concrete(CTSRC) stub columns and 2 common steel reinforced concrete(SRC) columns was investigated experimentally under static axial compression.The parameters considered in the study included the diameter-to-thickness ratio of the steel tube and the grade of the steel tube(Q235 and Q345).The test results indicated that the height of separated tubes in a CTSRC column had little effect on the axial load strength and ductility of CTSRC stub columns,and the diameter-to-thickness ratio had little effect on the ductility of axial loaded CTSRC columns.The axial load strength of CTSRC columns increased with the increase of the yield strength of the steel tube,which affected slightly the ductility of CTSRC columns.The axial load strength of a CTSRC stub column was remarkably higher than that of a common SRC column with the same steel ratio.The elastic-plastic analysis results of the steel tube indicated that the steel yielded under the peak load.A design equation to calculate the axial load strength of CTSRC stub columns as well as design advices were proposed based on the test and analysis results.