摘要
金属矿山采空区地面塌陷危险性预测过程中,仅利用灾害链进行程序评估预测,Lyapunov指数评估误差较大。考虑塌陷规模、特征、稳定性的数值模拟过程,设计一种基于岩体动力学演化模型的金属矿山塌陷区安全性Lyapunov指数评估方法。分析塌陷区冒落过程,结合顶板中拉应力和塌陷之间的关系,获取金属矿山塌陷区岩体弹性能等其他环境参数,利用岩体动力学演化模型进行数值模拟,直观定量地揭示出塌陷区内部动力学演化过程以及动力学特征;以塌陷区混沌时间序列为基础,得到重构相空间,根据光谱轨道的发散指数得到二维图像中的一条直线,利用最小二乘法逼近该直线,得到斜率具体值,即为目标最大Lyapunov指数。实验结果表明:该方法预测的两个监测点的安全性最大Lyapunov指数分别在61、62个月时超过0.3,监测点塌陷预测走势与实际的塌陷时间点更加吻合。降低了Lyapunov指数评估误差,为金属矿山塌陷区安全性分析提供新思路。
During the process of predicting the risk of ground collapse in the goaf of metal mines,only the disaster chain is used for program evaluation and prediction,and the Lyapunov index evaluation error is large.This paper considers the numerical simulation process of collapse scale,characteristics and stability,and designs a rock mass dynamic Lyapunov index evaluation method for safety of metal mine subsidence area based on scientific evolution model.The caving process in the collapse area is analyzed,and the relationship between tensile stress and collapse in the roof is combined to obtain other environmental parameters such as the elastic energy of the rock mass in the collapse area of the metal mine,and the dynamic evolution model of the rock mass for numerical simulation is used to reveal the collapse intuitively and quantitatively.Based on the chaotic time series in the collapsed area,the reconstructed phase space is obtained,and a straight line in the two-dimensional image is obtained according to the divergence index of the spectral orbit,and the least squares method is used to approximate the straight line to obtain the specific value of the slope,which is the target maximum Lyapunov exponent.The experimental results show that the maximum safety Lyapunov exponents of the two monitoring points predicted by this method are over 0.3 at 61 and 62 months respectively.The predicted trend of the collapse of the monitoring points is more consistent with the actual collapse time point.The evaluation error of Lyapunov index is reduced,which provides a new idea for the safety analysis of the subsidence area of metal mines.
作者
东秉正
DONG Bing-zheng(Dulan Jinhui Mining Co.LTD.,Dulan 816100,Qinghai,China;Qinghai 6th Institute of Geology and Mineral Exploration,Geermu 816000,Qinghai,China)
出处
《矿冶》
CAS
2023年第3期18-23,共6页
Mining And Metallurgy
