缺陷钢管混凝土偏压试件承载性能研究

Research on Bearing Performance of Defective Concrete Filled Steel Tube Members

目的研究3种缺陷类型钢管混凝土(CFST)偏压试件的承载性能.方法在冠状脱空试件承载性能试验研究的基础上,利用ABAQUS有限元数值模拟平台,分析不同缺陷类型(球冠形脱空、环向均匀脱空、复合缺陷)和不同缺陷等级(脱空率)等因素对CFST承载性能的影响.结果球冠形脱空缺陷降低了钢管对混凝土的约束效应,进而降低了CFST的极限承载力;环向均匀脱空缺陷不仅降低了CFST的承载力,而且改变了CFST试件的破坏模态;复合缺陷钢管混凝土试件的破坏模态与环向均匀脱空缺陷类似.结论环向脱空比球冠脱空缺陷对于CFST试件的极限承载力影响更显著,复合缺陷相较环向脱空缺陷对于CFST试件的极限承载力影响不显著.

Study the load-bearing performance of eccentrically compressed members of concrete filled steel tube(CFST)with three types of defects.Based on the experimental research of bearing performance,the ABAQUS finite element numerical simulation analysis platform was used to analyze the CFST of different defect types(spherical crown voiding,uniform circumferential voiding,composite defects)and different defect levels(gap ratio).The spherical crown-shaped voiding defect reduces the restraining effect of the steel tube on the concrete,thereby reducing the ultimate bearing capacity of CFST;the uniform circumferential voiding defect not only reduces the bearing capacity of CFST,but also changes the breakage of CFST members.Ring mode;the failure mode of the composite-defective concrete-filled steel tube members is similar to the ring-shaped uniform voiding defect.The ring-shaped voiding has a more significant effect on the ultimate bearing capacity of the CFST column than the spherical crown voiding defect.Circumferential voids have a more significant impact on the ultimate bearing capacity of CFST columns than spherical cap void defects,and composite defects have less significant effects on the ultimate bearing capacity of CFST columns than the circumferential void defects.