摘要
为提高钢管混凝土结构抗连续倒塌分析效率,采用子结构的静力试验和有限元方法进行研究,但是子结构模型的选取对分析结果影响较大。为此,利用ABAQUS显式模块对不同子结构模型的钢管混凝土组合框架进行抗连续倒塌性能分析。在验证材料本构和建模方法合理的基础上,建立单柱双半跨、三柱双跨、四柱三跨和五柱四跨平面子结构模型,以分析不同子结构模型对钢管混凝土平面框架抗连续倒塌性能的影响;对比单柱四半跨、五柱四跨和2×2跨的钢管混凝土空间子结构模型的抗连续倒塌性能,并分析混凝土楼板和层数对其影响。结果表明:不同子结构模型的选取决定了不同的边界约束条件,进而对钢管混凝土组合框架抗连续倒塌性能影响较大;单柱双半跨平面子结构和单柱四半跨空间子结构的边界强约束使其前期荷载较大,但整体变形能力较差;由于失效柱相邻柱的约束增强,四柱三跨、五柱四跨平面子结构的极限弦转角和峰值荷载较三柱双跨子结构明显提高,其中有楼板平面子结构的提高更明显;由于角柱的约束和楼板整体性的提高,有楼板单层2×2跨空间子结构的极限弦转角和峰值荷载均高于五柱四跨空间子结构,但无楼板单层2×2跨和五柱四跨空间子结构相差不大;无论楼板存在与否,随着层数的增加,空间子结构模型的极限弦转角和峰值荷载均大幅提高。
Both static tests and finite element( FE) analysis of substructures can be generally used for progressive collapse analysis of concrete-filled steel tube( CFST) structures. But different substructure models have influence on the results. In this paper,the progressive collapse resistance of CFST composite frames with different substructure models was analyzed by ABAQUS/Explicit module. On the basis of verified the material constitutive models and FE method,the single-column double-half span,three-column double-span,four-column three-span and five-column four-span plane substructure models were established to analyze the influence of different substructure models on the progressive collapse resistance of CFST plane frame. The progressive collapse resistances of single-column four-half span,five-column fourspan and two-by-two-span CFST space substructure models were compared,and the effect of concrete floor and number of layers were analyzed. The results show that the boundary restraint can be determined by the selection of substructure model,which has a great influence on the progressive collapse resistance of CFST composite frames. The strong boundary restraints of single-column double-half span plane substructure and single-column four-half span space substructure enhance the bearing capacity in the early stage but weakens the deformability. Due to the enhanced boundary restraint,the ultimate chord angle and peak load of four-column three-span and five-column four-span plane substructures are greater than those of the three-columns double-span substructure,especially with concrete floor. Because of the constraint of corner column and the monolithic floor,the ultimate chord angle and peak load of two-by-two-span space substructure are greater than those of five-column four-span substructure,but the difference between five-columns fourspan and two-by-two-span space substructures without concrete floor is small. With the increase of the number of layers,the ultimate chord angle and peak load of space substructure increase exponentially.
作者
郑龙
王文达
ZHENG Long;WANG Wenda(School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2020年第S01期76-88,共13页
Journal of Building Structures
基金
国家自然科学基金项目(51268038,51778274)
甘肃省高等学校协同创新团队项目(2018C-08)
关键词
钢管混凝土结构
空间框架
平面框架
子结构模型
ABAQUS显式模块
抗连续倒塌性能
concrete-filled steel tube(CFST) structure
space frame
plane frame
substructure model
ABAQUS/Explicit module
progressive collapse resistance
作者简介
郑龙,出生于1994年,男,博士研究生,主要从事钢-混凝土组合结构研究。email:cezhengl@163.com;通信作者:王文达,出生于1976年,男,工学博士,教授,主要从事钢-混凝土组合结构研究。email:wangwd@lut.edu.cn
