摘要
为研究聚丙烯纤维珊瑚海水混凝土的三轴受压力学性能,以侧向围压值、聚丙烯纤维体积掺量为变化参数,设计并制作了60个聚丙烯纤维珊瑚海水混凝土圆柱体试件,进行常规三轴受压加载试验。观测了试件的受力破坏形态,获取其应力-应变全过程曲线、峰值应力、峰值应变、弹性模量、耗能和损伤等性能指标,并深入分析了侧向围压值和纤维掺量对其力学性能的影响规律。结果表明:围压值为0(即单轴受压)时试件发生竖向劈裂破坏,随着围压值的增大,试件的破坏形态由竖向转变为斜向、应力-应变曲线更饱满,峰值应力、峰值应变、初始弹性模量和耗能均有显著提升;在三轴受压应力状态下,聚丙烯纤维掺量的增加对试件峰值应力、峰值应变、弹性模量的影响不大(变化范围在15%以内),但可以小幅提升耗能。最后,基于Mohr-Coulomb和Power-law破坏准则分析,给出了不同围压值时珊瑚海水混凝土的峰值应力和峰值应变预测式。
To investigate the triaxial compressive mechanical properties of polypropylene fiber reinforced coral seawater concrete,60 conventional traxial cylinder specimens were tested with the lateral confining pressure,the volume fraction of polypropylene fiber as design variation parameters.The failure mode of polypropylene fiber reinforced coral seawater concrete was observed,and the allprocess stress-strain curve,peak stress,peak strain,elastic modulus,energy consumption and damage were obtained.The influence of confining pressure and fiber volume fraction on mechanical properties was fully analyzed.The results show that,when the lateral confining pressure was 0(uniaxial compression),the specimens were cracked vertically.With the increase of lateral confining pressure,the cracks development of specimens changed from vertical to incline.And the shape of the stress-strain curves was fuller,the peak stress,peak strain,elastic modulus and energy consumption were also increased significantly.The polypropylene fiber volume fraction has little effect on the peak stress,peak strain and elastic modulus,the variation range is within 15%.Fiber volume fraction can slightly increase energy consumption.Finally,based on the Mohr-Coulomb and Power-law failure criterias,the prediction formulas of peak stress and peak strain of coral seawater concrete under different lateral confining pressures were proposed.
作者
沈建增
徐炜圣
梁莹
陈宗平
SHEN Jianzeng;XU Weisheng;LIANG Ying;CHEN Zongping(College of Architecture and Civil Engineering,Nanning University,Nanning 530200,China;College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education,Nanning 530004,China)
出处
《混凝土》
CAS
北大核心
2023年第5期96-102,107,共8页
Concrete
基金
国家自然科学基金(51578163)
八桂学者专项研究项目([2019]79号)
广西科技基地与人才专项(桂科AD21075031)
南宁市科学研究与技术开发计划重大项目(20223024)
广西重点研发计划资助项目(桂科AB21220012,2021AB31027)。
关键词
聚丙烯纤维
珊瑚骨料
海水
混凝土
三轴受压
polypropylene fiber
coral aggregate
sea water
concrete
triaxial compression
