Time-prediction of an onset of failure in full-scale model slope due to multi-step excavations based on Fukuzono formula

Abstract

Monitoring of displacement on full-scale model slope under multi-step excavation was implemented and the monitored data was analyzed to establish time-prediction procedure of an onset of slope failure due to excavation. The velocity of displacement showed not only increase but also decrease before failure. The relationship between the velocity of displacement and the acceleration of displacement showed different linear correlation between in positive acceleration region and in negative acceleration region. Time prediction was implemented based on the monitored displacement data. Several methods based on the relation between the velocity and the acceleration of the displacement proposed by Fukuzono were adopted for the prediction. Prediction based on non-linear regression analysis for the relationship between the velocity and the acceleration showed best result. The method only used displacement data for the region of positive acceleration and the relationship between the velocity and the acceleration wasn’t influenced so much by the disturbance of the data. This fact suggested picking up of displacement data for positive acceleration was necessary for stable result of time prediction by Fukuzono formula.