Experimental study on seismic response and progressive failure characteristics of bedding rock slopes

Abstract

Bedding rock slopes are common geological features in nature that are prone to failure under strong earthquakes. Their failures induce catastrophic landslides and form barrier lakes, posing severe threats to people's lives and property. Based on the similarity criteria, a bedding rock slope model with a length of 3 m, a width of 0.8 m, and a height of 1.6 m was constructed to facilitate large-scale shaking table tests. The results showed that with the increase of vibration time, the natural frequency of the model slope decreased, but the damping ratio increased. Damage to the rock mass structure altered the dynamic characteristics of the slope; therefore, amplification of the acceleration was found to be nonlinear and uneven. Furthermore, the acceleration was amplified nonlinearly with the increase of slope elevation along the slope surface and the vertical section, and the maximum acceleration amplification factor (AAF) occurred at the slope crest. Before visible deformation, the AAF increased with increasing shaking intensity; however, it decreased with increasing shaking intensity after obvious deformation. The slope was likely to slide along the bedding planes at a shallow depth below the slope surface. The upper part of the slope mainly experienced a tensile-shear effect, whereas the lower part suffered a compressive-shear force. The progressive failure process of the model slope can be divided into four stages, and the dislocated rock mass can be summarized into three zones. The testing data provide a good explanation of the dynamic behavior of the rock slope when subjected to an earthquake and may serve as a helpful reference in implementing antiseismic measures for earthquake-induced landslides.

Keywords

• Bedding rock slope
• Large-scale shaking table test
• Seismic response
• Progressive failure characteristics