Introducing a new criterion for tunnel crown settlement: a case study of Chehel-Chay water conveyance tunnel

Abstract

The study sought to analyse the settlement of Chehel-Chay tunnel and present a model and equation to predict the settlement of tunnel crown. Various methods such as numerical modelling, Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS) are employed and a new equation is presented. ANN and ANFIS’ modelling were carried out through monitoring the data related to about 68 various tunnels all over the world. The paper also utilised fitting curve toolbox to present an equation about the settlement of the tunnel crown. The settlement and displacement of 18 stations were observed through monitoring and the acquired results were compared to the predicted values. The results revealed that when the accuracy is more important, ANFIS method presented the most exact results. Moreover, when the time and simplicity is more important, the given equation was found to be the most proper method to predict the settlement of tunnel crown.