Stability analysis of earth slopes with counterweight fill: Kinematic limit analysis

Abstract

Counterweight fill, which involves adding mass to potentially unstable areas, such as the slope base or toe, is a common and effective technique for slope stabilization owing to its ease of installation and familiarity. As both a temporary and permanent preventive measure, both the design and analysis of counterweight fill require careful consideration to ensure a balanced distribution of the added weight. However, in practice, brief and empirical guidelines have been widely adopted, often without standardization. This study aimed to quantify the beneficial effects of counterweight fill on slope safety by analyzing the respective failure mechanisms. To achieve an optimal design, strategic fill configurations, including fill geometry, height, and area, are discussed. Further considerations include the strength and weight of counterweight fills, demonstrating the importance of fill positioning and material selection for slope stabilization. The addition of fill mass at the toe of the slopes could significantly strengthen the slope stability, potentially doubling the stability factors, assuming the fill used the same material as the slope. A strong dependence of the failure mechanisms of the fill-reinforced slopes was observed, leading to the potential local collapse of the restricted slope failure. The effectiveness of counterweight fills is affected by fill configuration and material properties, highlighting the importance of quantitative analysis and design.