基于EEMD-ELM的大坝变形预测模型

建立合理可信的大坝变形监控模型对科学有效地分析大坝变形监测数据和准确可靠地评估大坝工作运行状况意义重大。通过EEMD算法分解大坝变形量,得到代表不同特征尺度的本征模函数(IMF)分量,针对不同IMF分量选择不同影响因素,将各IMF分量作为极限学习机(ELM)的训练样本对大坝变形分量进行分析、拟合、预测,最后累加各IMF分量的预测结果得到大坝变形预测值。以某碾压混凝土重力坝为例,利用EEMD-ELM模型对大坝变形量进行预测,同时与BPNN模型和ELM模型的预测结果进行对比分析,其中EEMD-ELM模型的平均相对误差为0.566,较BPNN模型、ELM模型分别降低54%和14.8%,表明EEMD-ELM模型预测精度更高,具备一定的应用价值。

Prediction of Dam Deformation Using EEMD-ELM Model

A reasonable and credible dam deformation monitoring model is of great significance for scientific and effective analysis of dam deformation monitoring data and accurate and reliable evaluation of dam's working and operating conditions. The EEMD (Ensemble Empirical Mode Decomposition) model is adopted to decompose the dam deformation monitoring data, and the IMF (Intrinsic Mode Function) components representing different feature scales are obtained. With different influence factors for different components, the IMF components are used as the training samples of ELM (Extreme Learning Machine) to analyze, fit and predict the monitoring data. The predicted values of dam deformation are obtained by adding the values of each component. With a RCC (Roller Compacted Concrete) gravity dam as an example, the prediction result of EEMD-ELM model is compared with those of BPNN (Back Propagation Neural Network) model and ELM model. The comparison result reveal that the prediction accuracy of EEMD-ELM model is higher than that of BPNN model and ELM model, with the mean relative error merely 0.566, 54% and 14.8% lower than those of BPNN and ELM, respectively.