基于电流变化的水泥土损伤统计模型

为了把电阻率法引入水泥土的损伤研究中，首先把水泥土试块浸泡在清水、生活污水和造纸厂污水中，待龄期为90 d时进行无侧限抗压强度试验，并结合照片将试验过程得到的电流-应变曲线和应力-应变曲线进行了对比分析，然后以“有效电流”作为度量损伤的基准，通过统计得到了水泥土损伤模型，最后进行了归一化。研究表明，电流的变化易于测量，电流随着应变的增加而有规律的变化；电流-应变曲线与应力-应变曲线相互对应，都可以划分为4个阶段，这4个阶段很好地描述了水泥土损伤发展的全过程；本模型将全应变范围都统一成一个4次多项式方程，且方程形式与水泥类型、污染类型无关；这充分说明借助电流的变化来反映水泥土的结构损伤过程完全可行

A statistic damage model of cemented soil based on variation of electric current

In order to put the resistivity method into damage study, firstly soaking cemented soil sample in pure water, sewage and industrial wastewater for ninety days, the variation of its electric current are measured in the unconfined compression tests. Combining pictures, the relationships between the current-strain curves and stress-strain curves are compared. Being a basic parameter of the damage degree, the concept of “effective current” has been put forward; and based on it, the damage model of cemented soil is obtained through the statistical method. Finally, the damage model of cemented soil has been normalized. The analysis shows that the variation of current is easy to measure; and the current are varied regularly with the increase of strain. The current-strain curves and stress-strain curves can be divided into four stages which well describe the whole damage process of cemented soil. This model can be unified into a quartic polynomial equation in the whole strain range; and the equation form is irrelevant with cement type and pollution type. The results fully illustrate that it is completely feasible through the current changes to reflect the structural damage process of cemented soil.