Novel ice induced vibration testing in a large-scale facility: Deciphering ice induced vibrations, part 1

A method to measure the added mass and added damping in dynamic ice-structure interation: Deciphering ice induced vibrations, part 3

The influence of friction at the ice-structure interface on the induced vibrations

Vertically-sided offshore structures occasionally experience sustained vibration due to drifting ice sheets crushing against them. These vibrations may lead to problems associated with structural integrity and safety. Traditionally, three regimes of interaction are distinguished: intermittent crushing, frequency lock-in and continuous brittle...

The completeness of the set of modes for various waveguides and its significance for the near-field interaction with vibrating structures

Modal decomposition is often used in geophysics and acoustics for the solution of problems related to wave propagation in elastic or acousto-elastic waveguides. One of the key elements of this method is the solution of an eigenvalue problem for obtaining the roots of the characteristic equation, which may signify either frequencies or...

Ice-induced vibrations and ice buckling

Ice-induced vibrations can occur when flexible, vertically-sided offshore structures are subject to level ice such that the failure mode of ice is predominantly crushing. When the ice is relatively thin, or when the width of the structure is much larger than the ice thickness, the ice tends to buckle and subsequently fail as soon as the...

Initial results of a study into the estimation of the development of frequency lock-in for offshore structures subjected to ice loading

Ice-induced vibrations have to be considered in design of vertically sided offshore structures subjected to loading by sea ice, such as offshore wind turbines and oil- and gas platforms. The interaction between ice and structure may result in high global peak loads and the occurring structural vibrations can contribute significantly to the...

The effect of hydrodynamics on the bending failure of level ice

In this paper, the bending failure of level ice caused by the interaction with a downward sloping structure is studied in 2D. The focus is on the effect of hydrodynamics on the interaction. This study is done by comparing the predictions of a model that includes both hydrostatics and hydrodynamics with one that only includes hydrostatics.<br/...

Gyroscopically enhanced vertical axis pendulum for wave energy conversion

The vertical axis pendulum is a type of point absorber device which can absorb wave energy from a width exceeding the physical width of the device. Mechanical power is harvested from the rotation of the pendulum, in which the pivot point is directly connected to the generator. In this paper, a new concept of the vertical axis pendulum device is...

An effective fluid model for the bending failure of level ice

In this paper, the efficacy of an effective fluid model (EFM) is studied for replicating the effects that hydrodynamics has on the interaction between level ice, modeled as a semi-infinite Kirchhoff-Love plate, and a downward sloping structure, modeled as a rigid and immobile body. The proposed EFM is based on a distributed frequency-independent...

Vibration-assisted installation and decommissioning of a slip-joint

The structural failure of grouted connections for offshore wind turbines focused the industrial attention towards different and innovative solutions to guarantee a safe connection between the monopile foundation and the turbine tower. An alternative option to the traditional grouted joint is a direct steel-to-steel connection, also called a...