Abstract
Based on vertical stress increment due to pull-out of reinforcement, a model to evaluate shear strength on sliding surface in a reinforced soil structure was re-proposed. In order to verify the mechanism, a series of biaxial compression test during pulling-out of reinforcement was carried out. Based on test results, it was shown that the increment of shear strength was caused by pull-out of reinforcement. Furthermore, shear strength increment was evaluated based on relative displacement and stress increment.