Wind turbines that operate under cold climates sustain icing events. Ice accretion on the surfaces of wind turbine blades not only constitutes a severe threat to operation safety, but also reduces wind energy output. As a novel mechanical de-icing method, the ultrasonic de-icing technique has attracted high attention in both wind energy and aviation industry, due to its low energy consumption, light weight and low cost. According to the ultrasonic de-icing mechanism, a damage accumulation model was proposed to describe the ice detachment behavior under ultrasonic wave. This model that was constructed with damage mechanics provided an assessment method for the ultrasonic de-icing effect and predicted the time consumption of ice layer detachment. This method was numerically simulated with the finite element method. In addition, a set of experimental apparatus for ultrasonic de-icing method was designed. Following, a confirmatory experiment was carried out in laboratory environment. The parameters of the damage accumulation model were determined by the experimental data. The ice detachment behavior in the experiment was consistent with the prediction assessment proposed in this paper. (C) 2020 Elsevier Ltd. All rights reserved.