基于深度学习融合多源信息指标的坚硬顶板型冲击地压时序预警方法

Time-sequence early warning of hard roof rockburst based on deep learning fusion of multi-source information indicators

  • 摘要: 为了深入研究坚硬顶板地质条件下工作面的冲击地压预警问题,结合深度学习技术,提出了基于显式特征的物理预警指标和数据驱动的隐式特征时序预警指标融合的冲击地压时序预警方法,探究了大能量微震事件发生前多项物理预警指标的演化规律。利用遗传算法优化BP神经网络(GA-BP)算法筛选出微震活动平静度βn、小震动态参数P(b)、微震活动性指数A(b)、古登堡G-R关系经验常数b这4个适应于该坚硬顶板工作面的物理预警指标,并利用卷积神经网络结合t分布随机邻域嵌入(CNN-T-SNE)算法从微震和支架工阻数据中提取时序预警指标,采用星雀算法(Nutcracker Optimization Algorithm,NOA)、长短记忆神经网络(Long Short-Term Memory,LSTM)等深度学习算法,建立了坚硬顶板型冲击地压时序预警模型,并对模型预测性能进行了验证和实例分析。研究结果表明,采用GA-BP算法对微震信息指标进行反馈式迭代优选,基于预测F1值筛选出的物理预警指标为βnP(b)、A(b)、b,其预测F1值为0.88、均方根误差RMSE为0.038,筛选出的物理预警指标对冲击预警的敏感性较强,在大能量事件发生前,bP(b)、βn处于低值或快速下降状态,仅A(b)处于极大值或者接近极大值;通过CNN-T-SNE算法从微震和支架工阻数据中提取时序预警指标,T-SNE(T-Distributed Stochastic Neighbor Embedding)算法将CNN(Convolutional Neural Network)提取的特征进行降维可视化,不同的危险等级被明显区分开并有效提高了预测精度,其时序特征指标的预测F1=0.91、RMSE=0.021,微震和支架工阻指标的预测F1=0.80、RMSE=0.085,预警准确率提高了12%;采用星雀算法(Nutcracker Optimization Algorithm,NOA)对LSTM网络的学习率、批量大小、Dropout Rate 3个超参数进行寻优,其最优学习率为0.033、最优批量大小为8、最佳Dropout Rate为0.2,并通过LSTM-NOA网络对物理预警指标和时序预警指标进行训练学习,预测时长设定为1 d,其F1=0.96,与传统LSTM网络的预测方法相比,F1提高0.04,预警准确率提高了4%,且对大能量事件的敏感性更强。

     

    Abstract: In-depth research on the rock burst early-warning under hard roof geological conditions was conducted by integrating deep learning techniques. A time-series rock burst early-warning method was proposed based on the fusion of explicit physical warning indicators and data-driven implicit temporal warning indicators, and the evolution patterns of multiple physical warning indicators prior to high-energy microseismic events were investigated. The Genetic Algorithm-Optimized Backpropagation Neural Network (GA-BP) was used to screen four physical warning indicators suitable for the hard roof working face: microseismic activity quiescence βn, dynamic parameter of small earthquakes P(b) microseismic activity index A(b), and empirical constant in the G-R relation b. A Convolutional Neural Network combined with t-Distributed Stochastic Neighbor Embedding (CNN-T-SNE) was employed to extract temporal warning indicators from microseismic and support resistance data. Deep learning algorithms, including the Nutcracker Optimization Algorithm (NOA) and Long Short-Term Memory (LSTM) networks, were applied to establish a time-series early-warning model for hard roof-type rock bursts, and the model's predictive performance was validated and analyzed through case studies. The results show that: GA-BP-based feedback-iterative optimization screened βn, P(b), A(b), and b as physical warning indicators with prediction F1-scores of 0.88 and RMSE of 0.038, exhibiting strong sensitivity for impact warning. Before high-energy events, b, P(b), and βn values were at low levels or declined rapidly, while only A(b) remained at or near its maximum. The CNN-T-SNE algorithm effectively extracted temporal warning indicators, with T-SNE providing clear visualization and separation of different risk levels, improving prediction accuracy. The temporal feature indicators achieved an F1-score of 0.91 and RMSE of 0.021, while microseismic and support resistance indicators achieved F1-scores of 0.80 and RMSE of 0.085, representing a 12% improvement in warning accuracy. The NOA algorithm optimized LSTM hyperparameters, yielding optimal values of learning rate 0.033, batch size 8, and Dropout rate 0.2. The LSTM-NOA network, trained on both physical and temporal warning indicators with a one-day prediction horizon, achieved an F1-score of 0.96, representing a 0.04 improvement in F1-score and a 4% increase in warning accuracy compared to traditional LSTM methods, with enhanced sensitivity to high-energy events.

     

/

返回文章
返回