Probabilistic stability assessment of earthen levees subjected to earthquake loads

Earthen levees are critical flood protection infrastructure consisting primarily of earthen masses to retain water and secure the landside area against flooding. However, many earthen levees are located in the active seismic zone. Thus, it is critical to evaluate the reliability of earthen levees in the face of earthquake hazards, since the failure of such structures can be catastrophic and cause loss of lives, damages to properties, and significant adverse economic and societal impacts. This paper presents a simplified probabilistic assessment framework for earthen levees under earthquake loads. In this framework, the pseudo-static method with the finite element analyses is used for the stability analyses of earthen levees under earthquake loads. The pseudo-static method uses a static horizontally applied load to simulate the effect of an earthquake on the earthen structure. Then, the probabilistic assessment is conducted using an efficient reliability method that accounts for propagation of uncertainties from the input random variables through the finite element modeling. The effects of acceleration level on the probability of failure of earthen levees are quantified. The developed framework provides an efficient tool for probabilistic evaluation of earthen levees that is easy-to-use by practicing engineers. The results can help engineers to make a risk-informed decision in the face of earthquake hazards. A case study is utilized to demonstrate the effectiveness of the proposed framework for the reliability assessment of earthen levees under earthquake loads.