A phenomenological model for simulating ice loads on vertical structures incorporating strain rate-dependent stress-strain characteristics

Level ice acting on vertical structures can impose large loads and cause damage. Phenomenological models have been developed to simulate ice-structure interaction and predict ice loads, however due to oversimplification of ice properties and interaction mechanisms, existing models either cannot predict the interaction well or are applicable to limited situations, such as when ice is brittle. This paper first presents observations from existing experiments to identify key features and underlying mechanisms. Using these insights, a new phenomenological model is developed that captures the important phenomena under different strain rates. The proposed model comprises three essential components. The first is a strain rate-dependent stress-strain relationship that controls ice failure and the failure length. A new equation is proposed for the stress-strain relationship, and the empirical parameters are calibrated from published compression tests. The second component entails the modeling of ice failure length as a random variable. The third component accounts for spatial correlation of the failure lengths, by dividing the ice edge into multiple zones, and imposing correlation between zones. The model is validated against rigid indentation tests, and the predictions are found to match the experimental data well in terms of effective pressure, peak pressure, and time series of ice load. By artificially removing each component and comparing the simulation result with experimental data, it is demonstrated that all three components are crucial for good performance of the proposed method. (c) 2021 Elsevier Inc. All rights reserved.