A Semi-analytical Model for a Compaction-Grouted Soil Nail with Grout Bulb

The densification of surrounding soil from compaction grouting for the compaction-grouted soil nail is a significant merit to improve the pullout force. However, few studies was conducted to quantify the contribution of the compaction grouting to the pullout force, thus, a semi-analytical model was proposed. First, a hyperbolic model considers the soil-grout bulb (soil nail) interface behavior was established, and an energy transfer analysis model of a soil nail with grout bulb was proposed by combining the energy method and the hyperbolic model. Second, the semi-analytical model was verified based on the result of physical model test. Third, parametric study was conducted to evaluate the influence of the key parameter of the hyperbolic model on the pullout force with grouting process and those without.