摘要
以空心率、混凝土类型、长细比和偏心率为参数变量,共进行12根圆中空夹层钢管再生陶瓷混凝土压弯构件和4根圆中空夹层钢管普通混凝土压弯构件的对比试验研究。试验结果表明:试件均为整体失稳破坏,中长柱外钢管屈曲出现在端部及中部截面附近,偏心率越大,挠度发展更快,同时承载力和刚度降低,延性增大;长柱未出现屈曲现象,与中长柱相比,其承载力和刚度降低,延性变化不明显;本次试验的空心率对刚度和延性影响不明显;与普通试件相比,再生试件在弹塑性阶段刚度略有下降,二者后期延性接近。采用本文提出受钢管约束的再生陶瓷混凝土本构关系建模能较好地模拟出本次试件的破坏形态,模拟的荷载-挠度曲线与试验结果接近,计算的峰值荷载与试验值的之比差值均在5%以内;采用再生陶瓷混凝土本构关系与普通混凝土本构关系进行有限元模拟对比:与普通试件相比,再生试件承载力略微降低,弹塑性阶段刚度有所下降,但后期延性略有增加。荷载达峰值时,随着偏心率增大,混凝土承担的荷载比例逐渐增大;与长柱相比,中长柱承担荷载比例更大;由于内管承担了部分荷载,中空试件中混凝土承担荷载小于实心试件。
A total of 12 recycled ceramics concrete-filled double skin circular steel tubular members and 4 concrete-filled double skin circular steel tubular members were studied in a comparative test with hollow section ratio,concrete type,slenderness ratio and eccentricity as parameter variables.The test results show that the specimens are all subjected to overall instability failure,with the buckling of the outer steel tube of the medium-length column occurring near the end and the middle sections.The greater the eccentricity of the medium-length column,the faster the development of deflection,while the bearing capacity and stiffness are reduced and the ductility increases.No buckling appears in the long column,with bearing capacity and stiffness reduced and no significant changes in ductility compared with the medium-length column.The effect of hollow section ratio on stiffness and ductility of this test is not obvious.The stiffness of the regenerated specimen in the elastic-plastic stage slightly decreases compared with the common specimen,with similar late-stage ductility of both.The constitutive model of recycled ceramic concrete constrained by steel tube proposed by the paper can simulate the the failure mode of the specimens well,with the simulated load-deflection curve being close to the test results,and with the difference between the calculated peak load and the test value being within 5%.According to the comparison between the finite element simulation of the constitutive model of recycled ceramic concrete and that of ordinary concrete,the load bearing capacity of the recycled specimens is slightly reduced,and the stiffness decreases in the elastic-plastic phase,but the ductility increases slightly in the later phase compared with the ordinary specimen.At peak load,the proportion of load borne by the concrete gradually increases with the increase of eccentricity.Compared with the long column,the medium long columns bear a larger proportion of the load.The load borne by the concrete in the hollow specimen is less than that in the solid specimen because the inner tube bears part of the load.
作者
左勇
黄宏
王伊
王恺
ZUO Yong;HUANG Hong;WANG Yi;WANG Kai(State Key Laboratory of Rail Transit Infrastructure Performance Monitoring and Assurance,East China Jiaotong University,Nanchang 330013,China;China Railway Nanchang Group Company Ltd.,Nanchang 330002,China)
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2023年第9期185-194,共10页
Journal of the China Railway Society
基金
国家自然科学基金(51868020)
江西省青年科学基金(20192ACBL21002)
江西省教育厅科学技术研究(GJJ210649)。
关键词
中空夹层钢管混凝土
再生陶瓷混凝土
偏压试验
有限元分析
concrete-filled double skin steel tubular(CFDST)
recycled ceramics concrete
eccentric compression test
finite element analysis
