脱空对圆钢管混凝土受剪性能的影响分析  

EFFECTS OF GAPS ON THE BEHAVIOUR OF CIRCULAR CFST MEMBERS UNDER SHEAR

作　　者：叶勇[1] 韩林海[1] 陶忠[2] 

机构地区：[1]清华大学土木工程系,北京100084 [2]西悉尼大学基础设施工程研究所

出　　处：《工程力学》2016年第B06期62-66,71,共6页Engineering Mechanics

基　　金：中国博士后科学基金项目(2015M571044)

摘　　要：建立了考虑核心混凝土环形脱空缺陷的圆钢管混凝土受剪构件的有限元分析模型。在对模型可靠性进行验证的基础上,对带缺陷构件受剪承载力的影响因素进行了研究。研究结果表明,脱空降低了钢管混凝土受剪构件的极限剪应力,且降低程度主要与脱空率和剪跨比有关,而受混凝土强度、钢材强度和截面含钢率的影响较小。当剪跨比为0.5时,脱空对带缺陷构件的受力性能影响最为显著。基于参数分析,提出了不同脱空率情况下圆钢管混凝土构件的受剪承载力实用计算方法。A finite element model （FEM） is established with proper constitutive laws of materials, element types, meshing technology, and boundary conditions. After being verified with experimental results, the FEM is used to study the shear strength of circular concrete-filled steel tubular （CFST） members with a circumferential gap between the tube and concrete. The numerical investigation indicates that the existence of the gap decreases the ultimate shear strength of CFST members, and the influence is closely related to the gap ratio and the span-to-depth ratio. However, the influence of the concrete strength, steel strength and steel ratio on the shear strength reduction is less significant. When the span-to-depth ratio equals to 0.5, the gap has the most significant influence on the mechanical performance of CFST members with initial concrete imperfection. Based on the parametric study, a simplified formula is proposed to calculate the shear strength of circular CFST members with a circumferential gap.

关 键 词：钢管混凝土 脱空 受剪承载力 剪跨比 初始缺陷 

分 类 号：TU398.9[建筑科学—结构工程]