圆钢管型钢再生混凝土短柱轴心受压试验及有限元分析

Experimental Study and Finite Element Analysis of Axial Compression Behavior of Circular Tube Steel Reinforced Recycled Concrete Short Column

为研究圆钢管型钢再生混凝土短柱的轴压性能,本文对9根短柱进行了轴心受压试验,分析了短柱的破坏形态及设计参数对其轴压性能的影响。结果表明:短柱破坏形式为型钢先屈服然后钢管表面发生外鼓变形破坏,核心再生混凝土主要发生剪切破坏和压溃破坏;短柱轴压承载力随再生粗骨料取代率的增大而降低,但仍表现出良好的变形能力;增大钢管壁厚和型钢配钢率对短柱轴压性能是有利的。此外,通过ABAQUS软件对该短柱轴压性能进行了有限元分析,获取了短柱的整体变形图、应力云图及轴向荷载-应变曲线,并与试验结果进行对比。结果表明:有限元模拟结果与试验结果吻合较好。在此基础上,本文对该短柱轴压性能进行了参数分析。分析表明:短柱轴压承载力随再生混凝土强度的提高而增大,但变形能力有所降低;短柱轴压承载力随钢管及型钢强度的提高而增大,对变形能力影响不明显。上述研究结论对圆钢管型钢再生混凝土短柱的推广应用具有积极意义。

In order to study the axial compression performance of circular tube steel reinforced recycled concrete short column,9 short column specimens were designed for compression experiment.The failure pattern and influence of design parameters on axial compression performance of composite short column are analyzed.Experimental results indicate that the failure pattern of short column is steel tube yields first and then steel tube external surface bulges outwards.In addition,shear failure and crush failure are the main failure patterns of core recycled concrete.The axial compression bearing capacity of short column decreases with the increase of recycled coarse aggregate replacement ratio,while short column still exhibits good deformation ability.Increasing tube wall thickness and the steel ratio of section steel is beneficial to axial compression performance of short column.Finite element analysis of short column axial compression performance was carried out by using ABAQUS software;short column overall deformation,its stress nephogram and axial load-strain curve were obtained and compared with experimental results.Results show that finite element simulation results are in good agreement with experimental results.On this basis,parameters of short column axial compression performance were also analyzed.Analytical results show that short column axial bearing capacity increases with the increase of recycled concrete strength,but the deformation decreases a little.With the increase of steel tube strength and section steel strength,short column axial bearing capacity increases and its deformation varies little.Above conclusions can be helpful for the engineering application of circular tube steel reinforced recycled concrete short column.