Abstract: Anti-slide anchor pile is an important reinforcement measure for sliding (side) slope. The failure mechanism and monitoring warning have been the focus and difficulty of engineering because of big difference between the measured and theoretical values of pile and anchor’s stress and strain. By physical model tests on anchor piles,the evolution of anchor pile’s deformation and failure were analyzed. Data analysis,mathematical model fitting and other methods were adopted to obtain the safety early warning criterion for anti-slide anchor pile. Suggestions for safety monitoring during anchor pile’s construction and operation were proposed. Results show that anchor piles generally go through three stages,namely elastic deformation,elasto-plastic deformation,and plastic deformation from the beginning until the final destruction. Monitoring on the pile top displacement,pile’s strain and stress,and anchor force should be emphasized. The relationship between anchor bolt stress value and pile top displacement should be obtained to predict the yielding of anchor bolt.

Key words: anti-slide anchor pile, model test, landslide, safety warning criterion, monitoring suggestions