锈蚀圆钢管再生混凝土轴压短柱受力性能研究

以名义锈蚀水平(0%、10%和20%)为变化参数，设计了6根圆钢管混凝土短柱进行轴压试验，观察了锈蚀圆钢管混凝土短柱的受力全过程和破坏形态，得到了构件的应力-应变关系曲线，重点分析了锈蚀对构件轴压性能的影响，得出锈蚀圆钢管混凝土短柱刚度退化规律以及损伤演变规律。研究结果表明：随着锈蚀水平的提高，钢管混凝土柱的承载力均下降，组合弹性模量不同程度降低，刚度损伤增大；核心混凝土的类型对锈蚀构件承载力影响不大。采用钢管壁厚折减法结合ABAQUS有限元软件对构件在轴压荷载作用下荷载-变形关系进行模拟，同时根据GB 50936—2014《钢管混凝土结构技术规范》公式进行计算，试验结果与模拟结果以及计算结果基本一致。采用钢管壁厚折减法能够有效计算锈蚀圆钢管再生混凝土的承载力。

Axial compressive behavior of recycled concrete filled corroded circular steel tubular columns

Compression tests of six concrete filled circular steel tubular columns were conducted. The main parameter was the nominal corrosion level, namely 0%, 10% and 20%. In the tests, the whole loading process and failure mode of all concrete filled circular steel tubular columns were observed, and the stress-strain curves were obtained. The influence of the corrosion level on the axial compressive behavior of the specimens was analyzed. The law of stiffness degradation and the evolution law of damage of concrete filled corroded circular steel tubular columns were obtained. The results show that the bearing capacity of the specimens and the composite elastic modulus decrease, and the stiffness degradation increases with the increases of corrosion level. The type of core concrete has almost no effect on the bearing capacity of the corroded columns. Furthermore, the wall thickness reduction method of the outer steel tube was used with the ABAQUS software to simulate the load-deformation relationship of the columns under axial compressive load. In addition, the bearing capacity was calculated by the formula in GB 50936—2014. The experimental results are consistent with the simulation results and the calculation results. The wall thickness reduction method of the outer steel tube can effectively calculate the bearing capacity of recycled concrete filled corroded circular steel tubular columns.