Combined prediction of old goaf residual deformation
Residual deformation brings potential risks to the safe operation and maintenance of major structures in the underlying old goaf.Reliable deformation prediction is of great significance to ensure the safe reuse of territorial space in underground coal mining areas.Aiming at the problem that the prediction model of residual deformation has a significant impact on the prediction result due to the difficulty in obtaining modeling data or the deficiency of the model itself,a GM(1,1)-BP-RCRM-CM model based on data structure decomposition is proposed in this paper.Firstly,Newton interpolation method was used to interpolate the model training data to make them equally spaced.Then the monitoring data of the old goaf residual subsidence was decomposed into trend and disturbance terms by symmetric sliding average method,and the end value of the front-end lost value after the decomposition of monitoring data series was supplemented by an autoregressive model.Secondly,GM(1,1)-RCRM model and BP-RCRM model were used to predict the trend term and the disturbance term respectively.Finally,the prediction results of trend item and disturbance item were combined as the overall prediction results,and the average absolute percentage error was used to evaluate the model fitting accuracy and prediction accuracy.The experimental results show that:The GM(1,1)-BP-RCRM-CM model has high consistency in predicting the residual settlement at different monitoring locations,which is in line with the objective law that the prediction accuracy of the prediction model decreases gradually as the period progresses.The predicted results are more in line with the actual situation,and more robust than GM(1,1)-RCRM model and BP-RCRM model.
old goafresidual deformationcombination predictiondata decompositionresidual correction