混凝土电导率与应变关系的实验研究

采用直流电路法,对石墨混凝土试件在单次及反复荷载作用全过程中的导电及受力性能进行了测定·结果表明:用直流电路测量混凝土的电导率简单稳定;测出的电导率 应变关系和应力 应变关系具有明显的对应性,电导率变化与应力变化几乎同步,应力变化幅度较小时电导率变化幅度也较小,但电导率峰值出现在应力峰值附近,有53%出现在应力峰值之前,27%同时出现,20%在后;电导率 应变全过程曲线离散性较小,各曲线上升段的倾角范围在74 1°～86 6°之间·电导率的变化可以本征地反映混凝土的损伤·

Experimental Investigation on Relation Between Electrical Conductivity and Strain of Concrete

Electrically conductible concrete formed by adding graphite into common concrete possesses good mechanical and electrical properties of which the specimens were tested for their conductivity and mechanical properties by direct-current measurement in the whole process under the actions of single and cyclic loading. The results show that the conductivity measured by DC is easy to do and stable, by which the stress-strain and conductivity-strain relationships are obviously correspondent with each other and the changes in conductivity and stress are almost synchronous, i.e., the conductivity changes a little when stress does. Furthermore, the peak values of conductivity occur near those of stress: 53% before those of stress, 27% at the same time and 20% after them. The curves of the process of conductivity-strain relationships shows small discretization, with the slope of curves' ascending portion in a range from 74.1° to 86.6°. The change of conductivity can represent how the concrete has been damaged intrinsically.