内置复材管局部弱约束混凝土方柱受压性能研究

EXPERIMANTAL STUDY ON COMPRESSION PERFORMANCE OF CONCRETE-ENCASED FRP CONFINED CONCRETE SUB-COLUMNS / CORES COLUMNS WITH WEAK CONFINE

基于约束混凝土提出一种由钢筋、混凝土及缠绕管组成的内置复合材料管局部约束混凝土组合柱(ConcreteEncased FRP Confined Concrete Sub-Columns/Cores Column,简称"CEFC"),本构件截面形式为外围的钢筋混凝土类方柱和内置于4角点的FRP管约束混凝土圆柱(Concrete-Filled FRP Tube,简称"CFFT")组合而成。通过试验研究及有限元数值模拟对钢筋混凝土柱及内置复合管局部弱约束混凝土方柱进行了轴偏压作用下力学行为的分析和比较。结果表明,弱约束CEFC典型破坏模式为局部破坏,内置CFFT可较好延缓构件整体破坏。CEFC在轴压和偏压作用下延性都有所提高,且在偏压作用下CEFC具有明显的二阶刚度,且承载力具有小幅度提高。

A novel column named concrete-encased FRP confined concrete sub-columns / cores column（ CEFC）consisting of steel rebar,concrete and fiber-reinforced polymer（ FRP） tube is presented. The sectional form of CEFC consists of the outer common reinforced columns（ RC） and 4 inner Concrete-Filled FRP Tubes（ CFFT）,which located near 4 corners of square CEFC. The compression performance of RC and CEFC were studied and compared through experiment and Finite Element Method（ FEM）. The result indicates that the typical failure mode of CEFC with weak confine was local crushing and overall damage of CEFC was prevented by CFFT. What＇ s more,ductility of CEFC was improved. Moreover,second order stiffness and enhancement of strength were observed when CEFC was under eccentric compression.