摘要
通过人工气候模拟实验室对6榀剪跨比为2.6的钢筋混凝土(Reinforced concrete,RC)梁试件进行加速冻融循环试验,继而对其进行拟静力加载试验,根据试验结果分析了冻融循环作用和混凝土强度变化对RC梁试件破坏形态、滞回曲线、承载能力、变形能力和耗能能力等抗震性能指标的影响。结果表明:冻融后混凝土抗压强度降低,内部孔隙率变大,微裂缝增多,梁试件表面出现裂缝。各梁试件在拟静力加载试验后均发生了弯剪破坏。随着冻融循环次数的增加,试件的承载能力与耗能能力逐渐退化,延性先略微增长后显著下降;随着混凝土强度等级的提高,试件受冻融循环作用造成的损伤程度有所减轻,各试件的屈服、峰值、极限承载力均有所增大,耗能能力增强,延性无明显变化。
An artificial climate simulation laboratory was used to perform an accelerated freeze-thaw cycle test on six reinforced concrete(RC)beam specimens with a shear-span ratio of 2.6,which were then subjected to quasi-static loading.According to the test results,the effects of the freeze-thaw cycles and concrete strength grades on the seismic performance indicators of RC beam specimens such as the failure mode,hysteretic curve,strength,deformation capacity and energy dissipation were analyzed.The results show that after the freeze-thaw cycles,the compressive strength of the concrete decreased,the internal porosity of the concrete became larger,the micro-cracks were increased,and cracks appeared on the surface of the beam specimens.Six beam specimens exhibited a flexure-shear failure mode after the quasi-static test.With the increase in the number of freeze-thaw cycles,the strength and energy dissipation capacity degraded,and ductility first increased slightly and then decreased greatly.With the increase in the concrete strength grade,the degree of damage caused by the freezethaw cycle of the beam specimens was reduced,the yield,peak and ultimate strengths of specimens were increased,the energy dissipation capacity was enhanced,and the ductility was not significantly changed.
作者
郑山锁
姬金铭
裴培
贺金川
张艺欣
董立国
ZHENG Shan-suo;JI Jin-ming;PEI pei;HE Jin-chuan;ZHANG Yi-xin;DONG Li-guo(School of Civil Engineering,Xi’an University of Architecture&Technology,Xi’an,Shaanxi 710055,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education(XAUAT),Xi’an,Shaanxi 710055,China;The Institute of Architectural Design and Research of Xi’an University of Architecture&Technology,Xi’an,Shaanxi 710055,China)
出处
《工程力学》
EI
CSCD
北大核心
2020年第11期97-107,共11页
Engineering Mechanics
基金
国家重点研发计划课题项目(2019YFC1509302)
国家自然科学基金计划项目(51678475)
西安市科技计划项目(2019113813CXSF016SF026)
陕西省教育厅产业化项目(18JC020)。
关键词
RC梁
低剪跨比
冻融循环
拟静力试验
抗震性能
RC beam
low shear-span ratio
freeze-thaw cycle
qausi-static tests
seismic behavior
