基于突变理论的崩落法转充填法隔离矿柱安全厚度计算

崩落法转充填法开采过程中,合理确定隔离矿柱厚度对保证过渡采场安全回采具有重要意义。通过构建隔离矿柱力学模型,分析隔离矿柱破坏特征,建立了隔离矿柱的系统总势能关系式;基于突变理论,推导出隔离矿柱失稳的尖点突变模型;根据尖点突变模型失稳的充分条件和必要条件,建立了隔离矿柱安全厚度的计算模型。将此计算模型应用于研究鄂东某铁矿无底柱分段崩落法转充填法隔离矿柱厚度,理论计算的隔离矿柱厚度取值范围为15.49～19.36m。在数值模拟验证和工程试验生产中,取隔离矿柱厚度为17.50m时,隔离矿柱处于稳定状态。理论分析和验证结果表明,突变理论可解释隔离矿柱失稳的非线性动力学特征,隔离矿柱安全厚度计算模型可为工程设计提供一定的理论依据和工程指导。

Calculation on safety thickness of partition pillar from caving method to filling method based on catastrophe theory

In the process of transition from caving method to filling method, reasonable determination of the thickness of the partition pillar is of great significance to ensure the mining safety of transition stope. First, the mechanical model was established and the failure characteristic of the partition pillar was analyzed, the system total potential energy formula of the partition pillar was established. Second, based on catastrophe theory, the cusp catastrophe model for the instability of the partition pillar was deduced. Finally, According to the cusp catastrophe model instability sufficient condition and necessary condition, the calculation model of the safety thickness of the partition pillar was established. This calculation model was applied to study the thickness of the partition pillar from caving method to filling method at an iron mine in the east of Hubei Province, the theoretical calculation of the thickness of the partition pillar ranged from 15.49m to 19.36m.In the verification of numerical simulation and the production of engineering test, when the thickness of partition pillar is 17.50m, the partition pillar was in stable state. The theoretical analysis and verification results show that the catastrophe theory can explain the nonlinear dynamic characteristic of the partition pillar instability. Besides, the calculation model of the safety thickness of the partition pillar can provide a theoretical basis and engineering guidance for the engineering design.