模拟岩石声发射及混沌性的PCA模型

PCA model for simulating AE and chaos in rock failure process

根据岩石的细观非均质特征 ,从基本的能量传递规则出发 ,建立了一种新的物理元胞自动机PCA理论 ,它能够对岩石等细观非均质材料破坏演化过程中的声发射及混沌性进行有效模拟。经对较均质的粗面岩与较不均质的花岗岩AE混沌性模拟结果表明 ,其最大Lyapounov指数分别为 0 .45和 0 .6 2 3,即非均质性越强 ,混沌性就越强 ,对其岩石破坏力学行为的预测就越困难。模拟得到的声发射曲线与Mogi.K的实验结果基本吻合。PCA模型突破了传统元胞自动机模型仅限于数学意义上的运算规则 ,发展成为一种研究岩石破坏演化过程中声发射规律及非线性特征物理力学方法。

Based on the physical and mechanical characters of micro-heterogeneous material as rock, a new theory of physical cellular automaton (PCA) which can simulate acoustic emission and chaos in the failure evolving proces of micro-heterogeneous rock is set up, according to the energy transfer law. With simulating for homogeneous grit and heterogenous granite by PCA, the Lyapunov exponents are 0.45 and 0.623. Therefore, the larger heterogenous of rock, the stronger chaotic of mechanical behavior, this leads to much more difficult to predict the rock failure evolving process. The AE simulating results by PCA accord with the Mogi's laboratory results perfectly. PCA breaks through the mode of classical cellular automaton only is used as a mathematical operation and is developed to an effectively physical and mechanical method.