基于变权理论的煤层底板突水脆弱性评价方法研究

Floor water inrush shows complex nonlinear dynamic characteristics under the influence of multiple factors. However, the evaluation technique of multi-source information fusion based on constant weight neglects the influence on water inrush from internal differences of main controlling factors. In order to solve the defects and improve the prediction accuracy, this topic will introduce theory of variable weight into the forecast evaluation of floor water inrush. On the basis of field investigation and data collection, this topic will establish an index system of main controlling factors which affect floor water inrush, and then, through the theoretical research and test analysis, determine the variable weight interval threshold and the parameter values for adjustable weights using mathematical methods, such as fuzzy mathematics and statistical analysis, and build the floor water inrush prediction model based on the variable weight theory, which conforms to the evaluating characteristics of floor water inrush. Then, compare with the assessments of constant weight model and traditional water inrush coefficient method to test the evaluation result further, thus establish the forecast evaluation theory and method system of floor water inrush based on variable weight model. This method can comprehensively consider the relative importance of main controlling factors, the status values change of various factors of evaluation units and the dynamic control function of multi-factor index values under different combination states on floor water inrush, reflect the complex nonlinear dynamic process of floor water inrush under the influence of multiple factors, thereby improve the prediction accuracy effectively.

由于多因素影响下煤层底板突水具有复杂非线性动态特征，而基于常权评价的多源信息融合技术忽略了各主控指标内部差异性对突水的影响；为解决该缺陷，提高预测预报精度，本课题将变权理论引入煤层底板突水预测评价中。在现场调研、资料收集的基础上，建立影响煤层底板突水的主控因素指标体系；进而通过理论研究和测试分析，并利用模糊数学、统计分析等数学方法对模型中的变权区间阈值和调权参数值进行确定，构建符合煤层底板突水特征的基于变权理论的煤层底板突水预测预报模型；然后，通过与常权预测模型和传统突水系数法评价结果的对比，进一步检验评价效果，从而建立基于变权模型的煤层底板突水预测评价理论与方法体系。该方法能够综合考虑各主控因素的相对重要性，以及评价单元各因素的状态值变化和多种因素指标值在不同组合状态下对底板突水的动态控制作用，能够反映多因素影响下煤层底板突水的复杂非线性动力学过程，从而有效提高预测预报精度。

针对煤层底板突水常权评价模型中存在的不能考虑各主控因素在多种组合变化状态下对煤层底板突水的动态控制作用等问题，课题调研了大量煤层底板突水案例，经实验分析和数值模拟，对各个不同主控因素变权评价特征进行了分析总结，构建了符合煤层底板突水变权评价规律的状态变权向量。提出了应用K-均值聚类法，经迭代分析确定了各主控因素变权区间阈值，划出了各主控因素变权区间。根据约束条件，求出了变权模型中的各参数值，构建了基于变权模型的煤层底板突水脆弱性评价模型，真实反映了多因素影响下煤层底板突水的非线性动力过程，考虑了指标值内部差异性对评价结果的影响，刻画了各主控因素因水文地质条件变化造成的因素指标值突变对突水的动态控制作用。项目选取蔚县矿区2对典型矿井为工程示范点，开展了基于变权的煤层底板突水评价研究，评价结果比常权模型评价结果更吻合实际，精度更高，得到了生产单位的好评。研究还对变权模型中调权参数和主控因素参数对突水脆弱性指数的影响进行了灵敏度分析，分析结果为变权理论在煤层底板突水评价预测中的进一步应用和研究，提供了理论依据和参考。