Quantitative Risk Assessment of Cut-Slope Projects under Construction

Abstract

In some cut-slope projects landslide is a common problem during construction due to unfavorable geomorphological and geomechanical conditions. It is necessary to do a quantitative assessment of the risk posed by landslide before determining the budget or tender price. This paper outlines a general procedure for doing this, followed by an example to demonstrate the approach in comparison to a known failure. Finite-element analyses identify the most dangerous landslide scenario among all construction steps. The slope failure probability is then estimated using reliability theory based on the most dangerous construction step. After identifying the potential failure surface and estimating the volume of the sliding mass, the runnout behavior of sliding mass is simulated to delimit the extent of likely impacted area. Then, the exposed elements at risk and their vulnerabilities are identified and analyzed. The landslide risk is assessed quantitatively for three types of consequences: casualties, economic loss, and time overrun. Compared with actual consequences, the estimation results were in acceptable agreement with the case study. The paper demonstrates that it is feasible to analyze the risk associated with landslides during construction of cut-slopes.