深部走向长壁开采地表移动数值模拟

摘要

在对深部开采进行界定的基础上,运用数值模拟手段,基于关键层理论建立三维深部开采模型,对走向长壁式开采地表移动进行分析,数值计算所得三维地表移动图形能够定量、直观描述地表移动,结果与概率积分法预测符合良好,实现对采煤-上覆岩土层破坏-地表沉陷全过程分析,是对煤矿开采沉陷可视化工作的重要补充.通过数值计算,总结了深部开采地表移动特点,并对比深部开采与浅部开采,分析地表影响半径及相关变形指标.分别对充分采动和非充分采动条件下概率积分法下沉系数进行计算,并与传统计算方法进行比较,结果显示:两种开采条件下,下沉系数均小于传统计算结果,基于浅部开采的经验下沉系数不再适合深部采动情况,得出下沉系数随深度增大而变小的结论,并分析这种变化产生的原因.%Based on the definition of deep mining, this paper used numerical simulation methods, by setting up a 3D deep mining model, to analyze surface movement under long-wall mining condition. The 3D surface movement graphics can be used to quantify the surface movement and to describe it perfectly. The results match those with the probability integral method, and the whole process analysis of coal mining-strata damage-surface subsidence is realized. It is an important complement to the coal mining subsidence visualization work. Through numerical simulation, the deep mining surface movement characteristics are summarized and compared to the shallow and deep mining, and the influence radius of surface deformation and related indexes are discussed. Calculation of sinking coefficients under fully mining and not fully mining conditions used in the probability integral method and comparison with the traditional calculation methods show that the sinking coefficient is less than the traditional calculation results. The experience of the shallow mining subsidence coefficient is no longer suitable for deep mining. The sinking coefficient becomes smaller with depth increase. The causes of this change are analyzed.