基于声发射特征的充填体损伤演化研究

发布时间：2018-10-12 14:20

【摘要】：为探究声发射信号与充填体细观破坏之间的关系,研究声发射特征振铃计数、能率和应力随时间的变化规律,进一步揭示充填体损伤演化过程,进行了全尾砂胶结充填体声发射特性力学实验。基于损伤力学理论并引入有效损伤率,得到基于声发射累积事件率的损伤变量,然后构建了充填体损伤本构方程。研究结果表明,声发射振铃计数和能率在不同受力阶段呈现不同变化,与充填体内部孔隙及裂纹损伤演化过程有密切关系。振铃计数在弹性阶段前期达到最大,屈服阶段逐渐降低至最小;有效损伤率值与理论峰值应力呈负相关;与实验峰值应力相比,理论峰值应力出现于应变较大处;充填体为高损伤介质,当有效损伤率取值趋近于1时,理论模型曲线与实验曲线变化趋势相同,可以较好的描述充填体应力应变关系。
[Abstract]:In order to explore the relationship between acoustic emission signal and mesoscopic failure of filling body, the characteristic ringing count, energy rate and stress change with time were studied, and the damage evolution process of filling body was revealed. A mechanical experiment on acoustic emission characteristics of cemented tailing filling was carried out. Based on the damage mechanics theory and the effective damage rate, the damage variables based on the cumulative event rate of acoustic emission are obtained, and then the damage constitutive equation of the filling body is constructed. The results show that the number and energy rate of acoustic emission ring have different changes at different loading stages, which is closely related to the process of pore filling and crack damage evolution. The ringing count reached the maximum in the early stage of elastic stage and decreased to the minimum in the yield stage; the effective damage rate was negatively correlated with the theoretical peak stress; compared with the experimental peak stress, the theoretical peak stress appeared in the larger strain. The filling body is a medium with high damage. When the effective damage rate approaches 1, the theoretical model curve is the same as the experimental curve, which can better describe the stress-strain relationship of the filling body.
【作者单位】：华北理工大学矿业工程学院;河北省矿业开发与安全技术重点实验室;
【基金】：河北省自然科学基金资助项目(E2016209224);河北省自然科学基金项目(E2014209093)
【分类号】：TU45

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