Application of Improved Grey Model Based on Cumulative Method to Deformation Prediction of Tunnel Surrounding Rock

The traditional GM(1,1) model was improved by using the cumulative to increase its prediction accuracy. Based on the measured data of the Laomu tunnel in section 10 of shiqian to yuping expressway, the traditional grey prediction model and the improved grey prediction model were used to predict the surrounding rock deformation of the tunnel. The research shows that the improved model prediction can reduce the probability of outliers and the data series fluctuation of traditional gray prediction model, and makes the predicted value closer to the measured value. Although the improved gray prediction model has a slightly single modeling step, it can effectively increase the prediction accuracy of the model in a short period of time, and has certain reference value for similar tunnel surrounding rock deformation monitoring projects.