内置碳钢不锈钢管海洋混凝土柱轴压试验及承载力计算

Axial Compressive Behavior and Bearing Capacity Calculation of Marine Concrete Filled Stainless Steel Tube Columns with Built-in Carbon Steel Under Axial Compression

为研究不锈钢管海洋混凝土柱及内配碳钢后的轴压力学性能,以型钢类型、螺旋筋间距、纵筋直径为变化参数,完成了10个试件的轴心受压静力加载试验。观察了试件的受力破坏全过程及形态,获取了轴向荷载-位移曲线及各钢材应变曲线,基于试验实测数据,就各变化参数对试件的轴压承载力、延性、耗能能力和损伤发展的影响规律进行了分析。结果表明:不同试件的破坏形态相似,均表现为不锈钢管局部屈曲压皱,混凝土斜向剪切破坏;内置碳钢可以提高试件的极限承载力、轴压延性和耗能能力,抑制试件的损伤发展;在增加相同用钢量的条件下,增加圆钢管含钢量对试件轴压性能提升幅度最大;基于“复合约束叠加法”推导计算公式所得承载力计算值与试验值吻合良好。

To investigate the axial compressive behavior of marine concrete filled stainless steel tube column and built-in carbon steel marine concrete filled stainless steel tube columns,a total of 10 specimens were tested under axial loads.The mechanical failure process and morphology of the specimens were observed,and the axial load-displacement curve and the strain curve of each steel were obtained.Based on the test data,the influence of various variation parameters on the ultimate bearing capacity,axial ductility,energy dissipation capacity and damage development of kinds of specimen was analyzed.The results show that the failure modes of specimens are local buckling and wrinkle of stainless steel tube and oblique shear failure of concrete.The built-in carbon steel can improve the ultimate bearing capacity,axial ductility and energy dissipation capacity of the specimen,and inhibit the damage development of the specimen.Under the condition of increasing the same weight of steel,with the increase of content of circular steel tube,the axial compression performance improved most;the calculated value of bearing capacity based on the calculation formula of‘composite constraint superposition method’is in good agreement with the experimental value.