| Summary: | The vast natural resources, the opening of new shipping routes, and the increased interest to grow tourism in remote locations, is leading to a significant increase of number of vessels operating in the Arctic. Thus, to ensure that Arctic operations are safe, a better understanding on the interaction between ships and ice is required. The main aim of this thesis is to validate the use of an Inverse Load Sensing method for ice-induced loads on ships. The validation consists of comparing the results in terms of total ice-induced loads of the Inverse Load Sensing method and the results of a more widely used method, the Response Matrix method. The Inverse Load Sensing method uses full-scale strain measurements collected on the oblique icebreaker Baltika to estimate the magnitude of the load on the instrumented ship’s structures and the characteristics of the corresponding load patch. When assessing the accuracy of both methods involved in the validation process, the Response Matrix method is found to under- or overestimate known loads depending on their location. The overestimation was limited to 20% while underestimation could be significant for loads closer to the waterline stringer. The sources of inaccuracy are identified as being the rotation of frames and the limited extent of frame instrumentation. A correction factor is calculated which accounts for the inaccuracies of the Response Matrix method. The Inverse Load Sensing method is found to be accurate in the estimation of known loads. Peak loads are selected using the Rayleigh Separation method and the corresponding measured strain is used as input for the Inverse Load Sensing and the Response Matrix methods. The comparison of the results of both methods in terms of total ice-induced load shows a good correspondence, when the correction factor of the Response Matrix method is accounted for. An average difference of 3% is found between the results of both methods when the correction is used. Thus, the Inverse Load Sensing method is valid for ice-induced loads ...
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