Investigations for understanding the failure mechanism associated with vibration effects on open-pit slopes constituting of sand and gravel mixtures

A series of shaking table tests were conducted to investigate the failure mechanism of slope models prepared using sand and gravel mixtures derived from open pit slopes by subjecting them to vibration for extended periods of time. The dynamic response is analyzed based on the acceleration amplifications measured at different elevations. The horizontal PGA amplification factors first increase and then decrease with an increase in frequency, reaching a peak value at the natural frequency of 20 Hz. The horizontal PGA amplification factors increased for frequency values lower than 20 with an increase in the input amplitude; however, they decreased for frequency values higher than 20. An increase in excitation duration typically contributes to trigger slope deformation; however, its effect increases rapidly for longer excitation periods. A novel technique is developed for the estimation of the deformation in slope models using an image processing program for this study based on image recognition and data extraction. Furthermore, the slope stability behavior is analyzed based on the numerical simulations considering the disturbed state concept (DSC) for rigorous analyses. Results of this study are of interest in engineering practice applications for taking measures to prevent natural disasters associated with open pit slopes formed due to mining activity.