胶结充填体受压性能的非均质细观损伤研究

Study on heterogeneous mico-mechanics damage in compress performance of cemented filling body

基于细观力学,以灰砂比1∶8、料浆质量分数70%的尾砂胶结充填体为研究对象,建立满足Weibull统计分布规律的细观损伤演化方程和细观损伤本构方程,分析了不同均质度条件下的应力-应变曲线,并与实验曲线进行了比较。结合细观尺度破坏的数值计算,研究了胶结充填体细观损伤破坏机制。研究结果表明:建立的细观力学模型能够揭示充填体单轴条件下细观破坏机制;尾砂胶结充填体是一种低均质度的多项介质材料,峰值应力前具有明显的非线性特征,峰后残余应力具有持续降低特性;充填体的破坏是由细观单元损伤破坏导致的。

Based on micro-mechanics, the meso-damage evolu- tion equation and meso-damage constitutive equation were devel- oped in compliance with the Weihull statistical distribution law taking the cemented railings backfill body with cement and sand ratio is 1 t 8 and slurry concentration 70% as a research object. The stress-strain curves were analyzed under the conditions of different homogeneity and compared with the experimental curve. The meso-damage failure mechanism of cemented filling body was researched combined with the meso-structure numerical simula- tion. The results showed that the mesoscopic mechanics model built could reveal the microscopic damage mechanism under uni- axial conditions of backfill body and the cemented railings back- fill, a multiple dielectric material with low degree of homogenei- ty, has apparent nonlinear characteristics before former peak stress and has sustained reduction ch^tracteristics of residual stress after peak, and the backfill body damage is caused by the microscopic unit damage.