基于Weibull分布的充填体单轴压缩损伤模型研究

发布时间：2018-09-01 16:23

【摘要】：在矿山实际应力环境中,充填体多处于峰后变形阶段,研究充填体峰后强度特性对矿山安全生产十分重要。通过对灰砂比为1∶6、1∶8和1∶10的充填体试件进行单轴抗压试验,对比分析了不同灰砂比的胶结充填体变形破坏特征,灰砂比大的充填体具有更高的峰值强度和残余强度。基于统计损伤理论,确定了充填体损伤变量D并进行了修正,建立了可以表征充填体变形破坏全过程的损伤本构模型;由单轴抗压试验曲线几何特点,推导出该模型参数F0,m的数学表达式,α越小,充填体的峰后残余强度越高,F0和m越大,充填体峰值强度越大。对不同灰砂比的损伤演化规律进行了分析,各灰砂比的充填体损伤呈S型增长方式,灰砂比小的充填体能够承受更大的变形,更好的发挥其承载能力。结果表明该模型可以很好充填体破裂过程中的全应力-应变曲线和峰后残余强度的特性,为充填体强度设计提供参考。
[Abstract]:In the actual stress environment of the mine, the backfill is mostly in the post-peak deformation stage, so it is very important to study the post-peak strength characteristics of the backfill for mine safety production. Based on uniaxial compression tests of filling specimens with a ratio of 1: 6 to 1: 8 and 1:10, the deformation and failure characteristics of cemented fillers with different ratio of lime to sand are compared and analyzed. The results show that the filling with high ratio of lime to sand has higher peak strength and residual strength. Based on the statistical damage theory, the damage variable D of backfill is determined and modified, and a damage constitutive model which can represent the whole process of deformation and failure of backfill is established. The mathematical expression of the model parameter F0 / m is derived. The smaller the 伪, the higher the residual strength after the peak and the greater the peak strength of the backfill. The damage evolution law of different lime-sand ratio is analyzed. The damage of filling body with different lime-sand ratio is S-shaped. The backfill with small lime-sand ratio can withstand more deformation and exert its bearing capacity better. The results show that the model can provide a good reference for the design of backfill strength, which can be used for the full stress-strain curve and the characteristics of post-peak residual strength.
【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重点实验室;
【基金】：河北省自然科学基金项目资助(编号:E2015209172) 唐山市科技计划项目资助(编号:12140208A-12,12140208A-11)
【分类号】：TD853.34

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