Functional Relationship of Parameters in Different Theoretical Models for Ground Settlement Caused by Shield Tunneling

Abstract

The shield tunneling method has unique advantages and has been widely used in tunnel excavation. Therefore, it is important to study the ground settlement caused by shield tunneling. We considered the metro tunnel in Hohhot city, China, as a case study, and used various models to calculate the ground settlement separately. The optimal model was then identified by comparing the results with measured values. Based on this optimal model, we modified the parameters of other models, and derived the functional relationship among the parameters. Empirical formula model, equivalent ground loss model and stochastic medium (SM) theory model were used to calculate the settlement caused by shield tunneling, and the influence of the main parameters in each model was analyzed. The results show that the equivalent ground loss model provides settlement values closest to the measured values, and produces a stable calculation. The main parameters in the empirical formula and SM theory models have a little uncertainty, leading to small errors in the calculations. In summary, we established functions for the main parameters of the three models, allowing them to be unified to make the output of each model consistent and stable. We also proposed an approximate formula to solve the settlement problem in multi-layer soils.