基于初始孔隙率的千枚岩损伤模型分析

千枚岩由于成岩历史及赋存环境不同,内部的初始孔隙率不同,力学性质也相差很大。因此,在研究千枚岩的力学性质时,考虑初始孔隙率是非常有必要的。基于岩石的应变强度理论和Drucker-Prager(D-P)屈服准则,考虑了初始孔隙率对力学性质的影响,结合千枚岩的应力应变曲线,建立了基于初始孔隙率的千枚岩损伤模型。并通过对千枚岩岩样进行核磁共振试验和单轴压缩试验进行了验证。结果表明:建立的损伤模型能够较为准确的描述不同初始孔隙率条件下千枚岩的应力应变关系。本文模型对于千枚岩的损伤软化问题以及千枚岩力学性质的研究具有重要意义。

Study on damage model of phyllite based on initial porosity

Fracture joint development of phyllite structure, the initial porosity greatly affects the mechanical properties of phyllite, therefore, it is very necessary to study the mechanical properties of phyllite considering the effect of initial porosity. Based on rock strain strength theory and Drucker-Prager yield criterion, combining the stress-strain curve of phyllite, a constellation model of phyllite damage considering initial porosity is established. And verified by nuclear magnetic resonance test and uniaxial compression test of phyllite samples, the results show that the established damage model can accurately describe the stress-strain relationship of phyllite under different porosity conditions. This model is of great significance to the study of damage and softening of phyllite and the mechanical properties of phyllite.