方钢管再生混凝土柱的抗震性能试验及设计参数影响分析

Analysis on Seismic Performance and Design Influence Factors of Recycled Concrete Filled Steel Tube Columns

为了定量分析不同因素对方钢管再生混凝土柱在低周反复荷载下抗震性能指标的影响,选择再生骨料取代率、含钢率和轴压比为设计变化参数,开展了4根框架柱的拟静力试验。详细观测了框架柱破坏过程中及破坏后的形态,分析了实测滞回曲线,探究了设计变化参数对框架柱承载力、刚度、位移延性系数及耗能能力等抗震性能指标的影响规律。研究表明,方钢管再生混凝土柱的破坏形态同普通钢管混凝土柱相类似,都是柱底部钢管鼓曲、漆皮脱落及核心混凝土被压碎;随着再生骨料取代率的增大,柱的不同阶段的承载力、刚度、延性性能及耗能能力均有所降低;含钢率的增大对试件的位移延性系数、承载力、刚度、耗能能力起到有益作用;随着轴压比的提高,试件的延性性能及耗能能力有所降低,但其极限承载力、刚度却有所增加。

In order to study the effects of different factors on the seismic performance indexes of recycled concrete filledsteel tube frame columns under low cyclic loading,the three parameters such as recycled coarse aggregate replacement percentage,axial compression ratio and steel ratio are considered as design influence parameters,and four frame columns are tested under low-cycle repeated loading.The entire loading process and failure mode are observed,and the effects of these parameters on the seismic performance indexes such as strength,stiffness,ductility and energy dissipation coefficients of specimens are discussed.The study results indicates that the failure modes of recycled concrete filled steel tube columns are similar to that of normal concrete filled square steel tube columns,and all of specimen's failure modes are local steel tube buckled and concrete crushed at the bottom of columns.With the increase of recycled coarse aggregate replacement percentage,the strength,stiffness,ductility and energy dissipation coefficients of specimens in different stages are reduced.With the increase of steel ratio,the strength,stiffness,ductility and energy dissipation coefficients of specimens in different stages are raised.With the increase of axial compression ratio,the ductility and energy dissipation coefficients of specimens are reduced,and the other seismic performance indexes are raised.