The Study of the Compaction Grouted Soil Nail with Multiple Grout Bulks Using Finite Element Method

Soil nailing is a widely used ground stabilization technique utilizing the nail to retain soil mass, especially the cut and fill slopes. Since pull-out resistance is vital to the working capacity in field practice, so the study in enhancing the pull-out resistance is enormous. In this study, a series of model tests were conducted for the compaction grouted soil nail of single grout bulk, the results of which were compared to that of the 3D finite element method simulations. Since more grout bulks generate higher pull-out resistance, further finite element method simulations were conducted for the soil nails of double grout bulks of different diameter and spacing. However, due to the earlier appearance of failure for the soil nail of double grout bulks, the failure pull-out displacement was studied. The result shows, with the increase in diameter for the grout bulks, the failure pull-out displacement is decreased. In addition, the larger spacing is benefit to enlarge the failure pull-out displacement, however, the influence from the spacing enlargement is more significant to the soil nail of smaller grout bulk.