A METHOD TO CALCULATE LEVEL ICE LOADS ON MULTI LEGGED CONICAL STRUCTURES

摘要

Multi-legged structures are often used in arctic environments to withstand strong ice loads. Usually, these types of offshore structures have cones around their legs for the benefit of inducing level ice bending failure and thus reducing global ice loading. The present work introduces a method to predict global ice loads on multi-conical legged structures due to interaction with level ice by combining the Croasdale method and the formula of Mellor. The first one allows estimating forces of unbroken ice on front legs whilst the second one is applied to calculate broken ice forces on rear legs. Formation of ice circumferential cracks around the legs becomes an important assumption and it plays an important role in the calculations. Results are compared with available published data for multi-conical legged structures; nevertheless, further validation is suggested to prove applicability and to tune the proposed method.