Prediction Research of Using Grey Model for the Deformation of the Rock around Tunnels in the Initial Period of Tunnel Excavation

The author made some improvements on the obtained GM (1,1) model and built the improved GM (1,1) model which has fewer original errors, and the prediction results of the three kinds of models are also compared. the paper presents a new way for predicting the deformation of the rock around tunnels and support in the initial period of tunnel using Grey System Theory.