AN APPROACH TO CALCULATE GROUND DEFORMATION INDUCED BY INSTALLATION OF SINGLE HORIZONTAL JET GROUT COLUMN

During the construction of horizontal jet grouting, the high pressurized fluids (water or grout) are injected into the soil, and it may induce expansion to the ground, which will cause significant movements of the surrounding ground. Simplified analysis of the construction process of installation of horizontal jet grout columns is perform, based on Verruijt's solution for calculating the deformation by expansion of a circular cavity with uniform radial stress in a half space, and a method for predicting ground displacements caused by installing single horizontal jet grout column is proposed in this paper. The variation of stress state due to installation of horizontal jet grout columns is investigated, and the equation for determining the stress at the interface of the plastic and the elastic zones is established. Considering the common jetting parameters and the mechanical parameters of the surrounding soil, an empirical equation is proposed for determining the radius of plastic zone based on the principle of energy. Comparison between the calculated values and field data shows that the proposed method yields a reasonable prediction.