Lab physical modeling investigation on the pull-out resistance of grouted soil nail

An innovative laboratory pull-out box is introduced in this paper. The design of the pull-out box, instrumentations and test procedures are described in detail. Parameters that influence the pull-out behavior and pull-out resistance of soil nails such as overburden pressure, soil degree of saturation and grouting pressure were investigated in the tests. Test results showed that the pull-out resistance of a soil nail was not directly related to the overburden soil pressure. With the increase in soil degree of saturation, the pull-out resistance firstly increased and then decreased and the soil nail pull-out resistance increased significantly with the increase in grouting pressure.