大空心率圆中空夹层钢管超高性能混凝土短柱轴压力学性能研究

Axial Compressive Behavior of Ultra-high Performance Concrete Short Columns with Large Hollow Ratio Circular Hollow Sandwich Steel Tube

为研究大空心率的圆中空夹层钢管超高性能混凝土短柱的轴压力学性能,进行了6根大空心率的圆中空夹层钢管超高性能混凝土短柱和1根实心圆钢管超高性能混凝土短柱对比试件的轴压试验研究,分析了试件的破坏形态、荷载-应变关系曲线和横向变形系数。结果表明:大空心率的圆中空夹层钢管超高性能混凝土柱的轴压破坏形态表现为剪切型破坏和端部鼓曲破坏,其中内钢管在外钢管鼓曲的位置发生了向内的屈曲;随着空心率的增大,试件的承载力随之降低,试件的横向变形发展速度加快。采用有限元软件ABAQUS建立了轴压试件的分析模型,其中分别采用了两种混凝土本构关系模型进行了模拟,结果表明:采用两种混凝土本构关系模型模拟的破坏形态、极限承载力和荷载-应变关系曲线的弹性阶段都与试验结果基本吻合,它们的差异主要体现在极限承载力和荷载-应变关系曲线的下降段。

To study the axial compressive behavior of ultra-high performance concrete short columns of a circular hollow sandwich tube with large hollow ratio,six ultra-high performance concrete short columns of a circular hollow sandwich tube with large hollow ratio,and one solid round steel tube ultra-high performance concrete short column are carried out.The axial compression test study of the column contrast specimen,the failure mode of the specimen,the loadstrain relationship curve,and the transverse deformation coefficient are reported.The results show that the axial compression failure mode of the ultra-high performance concrete column of circular hollow sandwich steel tube with a significant hollow ratio shows shear failure and end bulge failure,in which the inner steel pipe buckles inward at the bulge position of the outer steel pipe;as the hollow ratio increases,the bearing capacity of the specimen decreases,and the development speed of the lateral deformation of the specimen accelerates.The finite element software ABAQUS is used to establish the analysis model of the axial compression specimen.Two concrete constitutive relationship models are used to simulate respectively.The two concrete constitutive relationship models’failure mode,ultimate bearing capacity,and ultimate bearing capacity are presented.The elastic stage of the load-strain relationship curve is consistent with the test results,and their differences are mainly reflected in the ultimate bearing capacity and the descending section of the load-strain relationship curve.