改进组合式十字形钢管混凝土柱力学性能研究

Mechanical Behaviors of Improved Composite Cross-Shaped Concrete-Filled Steel Tubular Columns

在传统异形钢管混凝土柱基础上,提出了一种施工方便的改进组合式十字形钢管混凝土柱,直接采用1个矩形钢管和2个U形槽钢焊接形成。为了研究改进组合式十字形钢管混凝土柱力学性能,采用ABAQUS分析了钢管厚度、混凝土强度、试件长度和偏心距对其力学性能的影响。研究结果表明:试件具有良好的承载力和延性;试件主要表现出中部鼓曲、中上部鼓曲及整体弯曲等3种典型变形形态;钢管厚度越大,钢管对混凝土的约束作用越强;增加钢管厚度对提高试件极限承载力的作用更明显;提高混凝土强度等级对试件延性不利;试件长度不大时,偏心距的增加对试件承载力及延性的影响均较小。

Based on the traditional special-shaped concrete-filled steel tubular columns,this paper presents an improved composite cruciform concrete-filled steel tubular columns,which is formed by welding 1 rectangular steel tube and 2 u-shaped channels.In order to study and improve the mechanical properties of composite cruciform concrete-filled steel tube column,ABAQUS is adopted to analyze the influences of steel tube thickness,concrete strength,specimen length and eccentricity on its mechanical properties.The results show that the specimens have good bearing capacity and ductility.The specimens mainly show three typical deformation patterns:middle drum,middle upper drum and overall bending.The greater the thickness of steel tube,the stronger the restraint effect of steel tube on concrete.The effect of increasing the thickness of steel tube on increasing the ultimate bearing capacity is more obvious and increasing concrete strength grade is unfavorable to ductility of specimens.When the specimen length is small,the increase of eccentricity has little effect on the bearing capacity and ductility of the specimen.