型钢再生混凝土组合柱滞回特性与耗能能力分析

Analysis of hysteresis characteristics and energy dissipation capacity of steel reinforced recycled concrete columns

为研究型钢再生混凝土柱在地震作用下的滞回特性与耗能能力,进行了17个型钢再生混凝土柱试件低周反复荷载试验,主要考虑了再生粗骨料取代率、轴压比、体积配箍率和剪跨比四个设计参数。观察了试件的破坏形态,分析了不同设计参数对试件滞回特性的影响,在此基础上,利用等效黏滞阻尼系数分析了不同设计参数对柱构件耗能能力的影响。研究结果表明:型钢再生混凝土柱主要破坏形态为剪切斜压破坏、弯剪破坏以及弯曲破坏,型钢再生混凝土柱的滞回曲线基本呈梭形状,较钢筋混凝土柱表现出较好的抗震性能。试件的耗能能力随再生粗骨料取代率的增加而降低,但降低幅度较小。随着轴压比的增大,试件耗能能力降低幅度较大。大剪跨比试件的耗能能力明显好于小剪跨比试件。此外,提高体积配箍率对于增强试件的耗能能力是十分有利的。

In order to research the hysteretic behavior and the energy dissipation capacity of steel reinforced recy- cled concrete （SRRC） columns under earthquake, 17 SRRC columns were tested by low reversed cyclic loading. Meanwhile, recycled coarse aggregates （RCA） replacement rate, axial compression ratio and stirrup ratio as well as shear span ratio were taken into account for the main design parameters of SRRC columns in this test. According to the experiment, the failure modes of specimens were observed and the influence of parameters on hysteresis behav- ior of specimens were also analyzed. On this basis, the influences of parameters on the energy dissipation capacity of columns were researched by the equivalent viscous damping coefficients. The results show that shear diagonal compression failure, shear bending failure and bending failure are the main failure modes of SRRC columns. The hysteretic curves of steel recycled concrete columns are shaped like spindle, which indicates that the columns have a better seismic performnce than the ordinary reinforced concrete columns. At the same time, the energy dissipation capacity of specimens decreases slightly as the increase of RCA replacement rate. By contrast, with the increase of axial compression ratio, the energy dissipation capacity of specimens decreases a lot. And the energy dissipation ca- pacity of specimen having a high shear span ratio is much better than the low one. Furthermore, the increase of stirrup ratio is very helpful to enhance the energy dissipation capacity of SRRC composite columns.