考虑力学参数关联的非均质煤概率模型

何考虑煤的力学参数之间的关联性是非均质煤储层模拟的关键。通过试验获得了阜新五龙矿某工作面102组煤样的弹性模量、单轴抗压和抗拉强度，定义了弹性模量无量纲因数、单轴抗压强度无量纲因数和抗拉强度无量纲因数及拉弹因数比、压弹因数比5个物理参数，并对试验数据进行统计分析，结果表明，（1）煤的弹性模量、单轴抗压强度和抗拉强度均具有统计分布特征，可以用Weibull分布描述；（2）弹性模量因数、单轴抗压强度因数和抗拉强度因数三者之间存在关联性;（3）拉弹因数比和压弹因数比都符合Weibull分布。以弹性模量为基准，建立了考虑参数关联的非均质煤随机概率模型，开发了相应的虚拟煤体生成程序。研究了2个数值算例，算例1分别按考虑力学参数关联和不考虑力学参数关联两种方法生成煤的力学参数，并与试验数据进行对比，结果表明，前者获得的结果与试验数据更接近；算例2对比了2种方法赋值的平面应变煤样单轴压缩下的宏观应力-应变曲线和煤样破坏过程，结果表明，考虑力学参数关联比不考虑力学参数关联得到的模拟结果更合理，利用文中模型能更好地模拟煤的非均质力学特性。

Probability model of heterogeneous coal considering correlation of mechanical parameters

How to consider the relevance of mechanical parameters of heterogeneous coal is a key issue to simulate coal bed. The 102 sets of experimental data including elastic modulus, uniaxial compressive strength and tension strength are derived from Wulong Mine of Fuxin city. Five dimensionless physical parameters including index of elastic modulus, index of uniaixal compressive strength, index of tension strength, index ratio of tension vs. elastic modulus (IRTE) and index ratio uniaixal of compressive strength vs. elastic modulus (IRUCE) are defined. Statistical analysis of the data shows that (1) Elastic modulus, uniaxial compressive strength and tension strength all follow statistical distribution, and may be fitted by Weibull distribution. (2) Indices of elastic modulus, uniaxial compressive strength and tension strength are correlative. (3) IRTE and IRUCE follow Weibull distribution. Then the probability model of heterogeneous coal with the correlation of the mechanical parameters is presented. The corresponding virtual generating system is developed. Two numerical cases are studied. In case 1 the virtual coal samples and the mechanical parameters are generated with the correlation and without the correlation of mechanical parameters, respectively; and the verifications are performed. The results show that the data from the former method are nearer to the experimental data. In case 2, the macroscopical stress-strain curve and the failure process of the numerical coal sample from the both methods under the conditions of plane strain and unaxial compression are studied. The simulating results from the former method are much better. Therefore the model proposed is a better way to simulate the mechanical heterogeneity of coal.