摘要
对超高韧性水泥基复合材料(UHTCC)进行单轴压缩疲劳试验,研究其压缩疲劳寿命、疲劳变形特征、纤维破坏形态以及疲劳寿命方程。结果表明:在单轴压缩疲劳荷载作用下,UHTCC材料的三阶段变形特征与普通混凝土以及钢纤维混凝土类似,所不同的是,该材料在疲劳荷载作用下的变形明显大于其静载包络线,具有更优异的变形能力,在疲劳破坏时呈现更显著的延性特征;疲劳破坏后,疲劳破坏面上的纤维受到严重挤压,其形态不同于纤维初始形态以及单调荷载作用下纤维的破坏形态。UHTCC材料的压缩疲劳寿命服从威布尔分布,p-S-N双对数方程可根据威布尔参数拟合得到。该研究结果可为UHTCC材料的工程应用提供参考。
This paper presents a cementitious composites （UHTCC）. relationship of ultra high toughness experimental study on compression fatigue properties of ultra high toughness In this study, the fatigue life, deformation capacity, fiber failure mode and p-S-N cementitious composites were investigated. It is observed that, the three-stage deformation pattern of ultra high toughness cementitious composites is similar to those of concrete and fiber reinforced concrete. In addition, different from concrete or fiber reinforced concrete, the maximum deformation of ultra high toughness cementitious composites at failure under fatigue load is larger than the monotonic envelope, which indicates this material owns higher deformation capacity and shows more ductility at failure. Moreover, the end of fibers on failure plane suffers from extrusion under fatigue load and shows a new failure mode, which is different from that of monotonic load. The fatigue life of ultra high toughness cementitious composites specimens obeys two-parameter Weibull distribution and the corresponding relationship between fatigue life and failure probability was given. When a failure probability p is given, the corresponding fatigue life N at certain stress level S could be calculated. The results of this investigation could be proposed for potential application of ultra high toughness cementitious composites.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2016年第1期135-142,共8页
Journal of Building Structures
基金
国家自然科学基金项目(51378462
51008270)
关键词
超高韧性水泥基复合材料
单轴压缩疲劳试验
变形特征
疲劳寿命方程
ultra high toughness cementitious composites
uniaxial compression fatigue test
deformation feature
p-S-N equation
