特厚坚硬顶板应变能积聚演化规律研究

Research on Strain Energy Accumulation and Evolution Law of Extra-thick and Hard Roof

采用三维有限元软件FLAC^(3D)建立特厚坚硬顶板模型,并利用弹性力学分析得出的由应力分量表示的应变能密度公式编写fish语言,代入数值模拟计算结果揭示了工作面推进过程中采场特厚坚硬顶板岩层能量积聚演化规律及分布特征。研究表明:特厚坚硬顶板岩层应变能分布与其所受应力条件密切相关,煤层开采后,工作面中部顶板岩层中弹性应变能较两端大;随工作面推进,坚硬顶板岩层中积聚的弹性应变能逐渐增加,应变能积聚范围扩大,峰值升高,能量梯度也随之加大。

In the study,an extra-thick and hard roof model was firstly established by the three-dimensional finite element software FLAC3D.Based on elastic mechanics analysis,the strain energy density formula expressed by the stress component was proposed.Afterwards,the corresponding fish language was written and used for numerical simulation.By numerical simulation,the evolution law and distribution characteristics of energy accumulation in extra-thick and hard roof rock strata of stope in the advancing process of the working face were revealed.The study showed that the strain energy distribution of extra-thick and hard roof rock was closely related to the stress conditions.After the coal seam mined,the elastic strain energy of the roof rock strata in the middle of the working face was larger than that of the both ends.With the advance of the working face,the elastic strain energy accumulated in the hard roof rock increased gradually,the range of strain energy accumulation expanded,the peak value increased,and the energy gradient increased accordingly.