基于二维云模型和Apriori算法的围岩稳定性分级研究

Classification of Stability of Surrounding Rock Based on Two-Dimensional Cloud and Apriori

针对围岩稳定性分级大多是对未受工程扰动岩体进行分级,以及分级结果难以为支护方式提供决策的现状,建立围岩稳定性的岩体及地质因素和工程因素二维分级指标体系。运用云理论确定岩体及地质因素和工程因素的等级期望值、熵和超熵,通过二维云发生器绘出围岩稳定性分级的二维云图,并向二维体系等级图进行投影,得到围岩稳定性的综合等级。将该模型应用于工程实例,并与一维云模型和实际进行对比,验证了该模型的准确性。该模型得到不同系统耦合作用下的围岩稳定性等级,实现了等级的可视化。通过Apriori算法进行关联挖掘得到围岩稳定性的综合等级决策表,可以快速确定工程的综合稳定性等级,并根据已知综合等级和岩体及地质因素等级确定工程因素的等级。

In response to the application of the most of traditional evaluation methods of stability of surrounding rock to the rock without engineering disturbance,and the failure of resulting evaluation grade to guide the choice of support mode in underground projects,a two-dimensional evaluation index system combined by the physical-mechanical and geological properties and the engineering factors of the surrounding rock was built.The two-dimensional cloud model was established drawing upon cloud theory to obtain the expectation,entropy and hyper entropy of the grade of the physical-mechanical and geological properties and the engineering factors of the rock mass,and two-dimensional cloud generators to plot the two-dimensional cloud atlas of stability evaluation of surrounding rock and then the comprehensive grade of surrounding rock was achieved.By application of the model to the engineering project and a comparison of the model with the one-dimensional cloud model and engineering practice,the evaluation result illustrates that this model is superior to others and consistent with engineering practice.The model obtained the stability grade of surrounding rock under the coupling effect of different systems,and realized the visualization of the grade.The Apriori algorithm was used to acquire the decision table of parameter design and support mode,which gives reference for parameter design and support mode selection.The inverse verification was conducted to prove the ranking result of the evaluation which offers the parameter design and support method choice to the next step of the engineering project.