Abstract：
The method of model dimension control to predict is put forward due to the weakness of GM(1,1) model in deformation prediction of tunnel surrounding rocks. Meanwhile, by means of math principle of GM(1,1) model, the study improves the calculating formula of background value model by using mathematical method in view of deformation features of tunnel surrounding rocks, and continuously updates prediction model by using equi-dimension substitution method. Compared with traditional GM(1,1) model, the improved model has gained higher prediction accuracy and can better predict the actual deformation conditions and trends of surrounding rocks.
