方中空夹层钢管混凝土纯扭力学性能研究

当中空夹层钢管混凝土构件用于高架桥桥墩、输变电杆塔、风力发电支架等时,其抗扭性能是十分重要的,纯扭性能的研究是进行压扭、弯扭、压弯扭力学性能研究的基础,因此有必要对中空夹层钢管混凝土纯扭的力学性能进行深入研究。以名义含钢率和空心率为变化参数,设计了4根方中空夹层钢管混凝土试件和1根实心方钢管混凝土试件,对其进行了试验研究,并且利用有限元软件ABAQUS对纯扭试件的扭矩—转角关系进行了计算。研究结果表明:所有试件具有良好的延性和后期承载力;名义含钢率越大,承载力越大;空心率为0.4的方中空夹层钢管混凝土与实心方钢管混凝土纯扭试件力学性能接近。采用本文的有限元方法可以较好地模拟方中空夹层钢管混凝土和实心方钢管混凝土纯扭试件的扭矩—转角关系全过程曲线。

Pure torsion behaviors of concrete filled double-skin (CHS inner and SHS outer) steel tubes

When concrete filled double-skin steel tubular(CFDST) columns are used as viaduct piers,power transmission towers,wind power stents and so on,their torsion properties are very important.A study on pure torsion is the foundation for compression torsion,bending-torsion and compression bending torsion,and is necessary for investigation of the pure torsion behavior of concrete filled double-skin steel tubular(CFDST) columns.A total of four concrete filled double-skin steel tubes and one concrete filled steel tube were designed and tested.The tubes were fabricated with circular hollow section(CHS) and square hollow section(SHS) as inner and outer skins,respectively.The parameters that vary in the tests were the nominal steel ratio and hollow section ratio.Torque-angle curves of the pure torsion were calculated by the finite element software,ABAQUS.The following conclusions can be drawn from the study: firstly,all the specimens have good ductility and post-bearing capacity;secondly,the greater the nominal steel ratio is,the greater the bearing capacity is;thirdly,when the hollow section ratio is 0.4,the concrete filled double-skin steel tubes with square hollow sections have the similar mechanical properties with the concrete filled steel tubes with square hollow sections;thirdly,the calculated results and the experimental results are basically equal.The finite element method can simulate the torsion behavior of concrete filled double-skin steel tubes and concrete filled steel tubes.