基于矿物组分与弹性参数的泥页岩脆性评价模型

Mud Shale Brittleness Evaluation Model Based on Mineral Composition and Elastic Parameters

基于泥页岩应力应变、X射线衍射实验进行模型优化。实验结果表明,泥页岩抗压强度与围压、杨氏模量呈正相关;体积应变量与杨氏模量呈负相关,而与泊松比呈正相关;脆性矿物有利于提高岩石的刚性,而黏土矿物使得岩石具有较强的蠕变性能。页岩中不同脆度的矿物在不同程度上控制着岩石力学性质,通过数值模拟,综合岩石力学参数和矿物组成提出了一种新的脆性评价模型,同时解决了杨氏模量与泊松比的权重分配问题,拟合效果优于前2种方法。

Based on the stress and strain,X-ray diffraction experiment,optimize the model. The experimental results show that compressive strength has positive correlations with Young′s modulus and confining pressure. The volume change of mud shale has positive correlations with Poisson′s ratio and negative correlations with Young′s modulus. Brittleness mineral is beneficial to increase the rigidity of the rock,and clay minerals have strong creep properties. Different brittleness in shale mineral controls the rock mechanics properties in different extent. By numerical simulation, integrating rock mechanics characteristics and mineral composition,put forward a new brittleness evaluation model,at the same time solving the Young′s modulus and Poisson′s ratio of the weight allocation problem. Effect is better than the former two methods.