摘要
采用分级增量循环加卸栽方式，对金川有色金属公司Ⅲ矿区软弱矿岩进行流变试验，探讨了软弱矿岩的黏弹塑性变形特性．建立了软岩的非线性蠕变模型．结果表明：分级增量循环加卸载下软岩有明显的瞬时应变硬化趋势，软弱矿岩JC1099试件的黏弹性应变分量与黏塑性应变分量之比为3．15～6．58，随应力水平的增加蠕应变中黏塑性应变占的份量总体上有增加走势；在低应力水平下，蠕变变形趋于稳定状态，在高应力水平下，软岩蠕变往往表现出加速蠕变特性．建立的非线性蠕变模型可以用统一的蠕变方程来描述软岩蠕变的3阶段，将该模型应用于金川Ⅲ矿区矿岩蠕变试验，蠕变试验曲线与理论曲线较为吻合．
A set of creep experiments was performed to study the viscoelastic behavior of soft ore-rock from the Jinchuan Mine Ⅲ under cyclical loading. A nonlinear creep model of the soft rocks was established. The results show that the instantaneous deformation modulus increases with increasing creep stress; Softer rocks have an enhanced ability to resist instantaneous elastic and plastic deformation during the step-loading and unloading in the cyclic process. The JC1099 specimen shows a ratio of visco-elastic strain to visco-plastic strain that varied from 3. 15 to 6.58. The ratio tended to decrease as the stress increased and creep deformation tends toward a steady state at low stress levels. Soft-rock-creep usually involves an accelerated creep at high stress levels. The nonlinear creep model can describe the three stages of soft rocks creep with a single expression. This model applied to the creep experiments on the ore-rock of the Jinchuan Mine Ⅲ makes predictions that are in good agreement with the experimental data.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2009年第1期34-40,共7页
Journal of China University of Mining & Technology
基金
国家自然科学基金项目(50774093)
2006年高等学校博士学科点专项科研基金项目(20060533071)
关键词
流变试验
非线性蠕变
损伤
硬化
软岩
rheological experiment
nonlinear creep
damaging
hardening
soft rocks
