随机非均质热弹性力学模型与岩石热破裂门槛值的数值试验研究

RANDOM NON-HOMOGENEOUS THERMAL ELASTIC MECHANICS MODEL AND NUMERICAL TESTS ON THERMAL CRACKING THRESHOLD OF ROCK

考虑岩石细观组构的不同,建立了随机非均匀介质的热弹性力学模型,给出了一般意义下的有限元分析方法。进而,仅考虑热膨胀系数为随机变量,在平面应力模型下,进行了岩石热破裂的数值试验,以花岗岩为样本,对均匀分布、正态分布、韦泊分布3种随机分布下热膨胀系数变化引起的岩石破裂门槛值的变化做了详细研究。结果表明,热膨胀系数的概率分布形式对花岗石热破裂规律及门槛值温度有重要影响。

Considering different microstructure of rock, random non-homogeneous thermal elastic mechanics model and finite element method (FEM) based on this model are put forward. Numerical simulation is made for plane stress state to study the influence of thermal dilatability on thermal cracking law and temperature threshold, and only thermal dilatability is considered as random variable and thermal dilatability is of uniform distribution, Gauss distribution and Weibull distribution. Simulations show that relationship between temperature threshold and thermal dilatability of uniform distribution is a line function, relationship between temperature threshold and thermal dilatability of Gauss distribution is a power function, and relationship between temperature threshold and thermal dilatability of Weibull distribution is a power function.