Abstract: The jet grout method is popular in soil improvement projects, such as dams and tunnel foundations etc. due to its cost efficiency and quick construction. The estimation of the column diameter of the jet grout is much more significant at the design stage. In this study, three optimal models with explicit formulas were established to predict the diameter of jet grout columns based on a comprehensive database summarized from different case histories around the world. The Bayesian model selection was used to determine the best model related to the three popular jet grout systems (i.e., single, double, and triple), respectively. The 95% credible intervals were estimated at the same time and the estimation on the column diameter of jet grout using the proposed models agrees well with the measured ones in practical projects. It is concluded that, except for the jet grout energy, the soil type has a significant influence on the diameter prediction of jet grout columns.

Key words: Jet Grout Column, Explicit Form, Bayesian Model Selection, Semi-Analytical Model