圆钢管再生混凝土柱抗震性能试验

Experiment on Seismic Performance of Recycled Aggregate Concrete Filled Circular Steel Tube Columns

为研究圆钢管再生混凝土柱的抗震性能,考虑不同再生粗骨料取代率、剪跨比、轴压比等参数,设计了7个足尺试件,进行拟静力试验研究,对比分析了各试件的破坏特征、滞回曲线、承载力、延性、刚度退化、耗能能力等特性.试验结果表明:加载后期,所有试件均在钢管底部出现环状鼓曲,剪跨比小的部分试件受拉一侧发生断裂;各试件的滞回曲线基本呈梭形,比较饱满,延性较好;不同粗骨料取代率对试件的抗震性能影响不大;随着剪跨比的增大,试件的承载力降低,延性变好;轴压比大的试件延性较差;各试件抗震性能良好,满足抗震要求.通过我国相关规范和规程对本文及其他文献中圆钢管再生混凝土柱压弯承载力的计算分析发现,对于足尺圆钢管再生混凝土柱,我国规范的相关公式是偏于安全的.

In order to investigate the seismic performance of recycled aggregate concrete filled circular steel tube columns,seven full-scale specimens with different replacement ratio of recycled coarse aggregate,shear span ratio,and axial compression ratio were designed,and their pseudo static test studies were carried out.The failure characteristics,hysteretic curves,bearing capacity,ductility,stiffness degradation and energy dissipation capacity of specimens were compared and analyzed.Test results showed that at the later loading stage all the specimens were found to have bulged outward on the bottom of steel tubes,and some of the ones with smaller shear span ratio had a fracture on the tensile side at the bottom.The hysteresis curves of the specimens basically presented the spindle shape and were relatively plump.The ductility of all the specimens was good as well.Different replacement ratios of coarse aggregate had little influence on the seismic performance of specimens.With the increase of shear span ratio,the bearing capacity of the specimens decreased while ductility increased.As the axial compression ratio increased,the ductility of specimens decreased.The seismic performance of specimens was good enough to meet the seismic requirements.Based on two relevant codes in China,the compression bending capacity of recycled aggregate concrete filled circular steel tube columns from this article and other documents was calculated and compared.It was found that the relevant formula in the codes of China were safe for full-scale recycled aggregate concrete filled circular steel tube columns.