Evolution of Design Method Against Random Waves Statistical Properties and Spectral of Sea Waves Transformation and Deformation of Random Sea Waves Design of Breakwaters Design of Coastal Dikes and Seawalls Probabilistic Design of Harbor Facilities Harbor Tranquility and Vessel Mooring Hydraulic Model Tests with Random Waves Theoretical Description of Random Sea Waves Statistical Theory of Irregular Waves Techniques of Random Wave Analysis 2D Computation of Wave Transformation with Random Breaking and Nearshore Currents Statistical Analysis of Extreme Waves Prediction and Control of Beach Deformation Processes.

Random seas and design of maritime structures

An idealised experimental model of ocean surface wave transmission by an ice floe

Operational ocean wave models need to work globally, yet current ocean wave models can only treat ice-covered regions crudely. The purpose of this paper is to provide a brief overview of ice effects on wave propagation and different research methodology used in studying these effects. Based on its proximity to land or sea, sea ice can be classified as: landfast ice zone, shear zone, and the marginal ice zone. All ice covers attenuate wave energy. Only long swells can penetrate deep into an ice cover. Being closest to open water, wave propagation in the marginal ice zone is the most complex to model. The physical appearance of sea ice in the marginal ice zone varies. Grease ice, pancake ice, brash ice, floe aggregates, and continuous ice sheet may be found in this zone at different times and locations. These types of ice are formed under different thermal-mechanical forcing. There are three classic models that describe wave propagation through an idealized ice cover: mass loading, thin elastic plate, and viscous layer models. From physical arguments we may conjecture that mass loading model is suitable for disjoint aggregates of ice floes much smaller than the wavelength, thin elastic plate model is suitable for a continuous ice sheet, and the viscous layer model is suitable for grease ice. For different sea ice types we may need different wave ice interaction models. A recently proposed viscoelastic model is able to synthesize all three classic models into one. Under suitable limiting conditions it converges to the three previous models. The complete theoretical framework for evaluating wave propagation through various ice covers need to be implemented in the operational ocean wave models. In this review, we introduce the sea ice types, previous wave ice interaction models, wave attenuation mechanisms, the methods to calculate wave reflection and transmission between different ice covers, and the effect of ice floe breaking on shaping the sea ice morphology. Laboratory experiments, field measurements and numerical simulations supporting the fundamental research in wave-ice interaction models are discussed. We conclude with some outlook of future research needs in this field.

Modeling ocean wave propagation under sea ice covers

A laboratory experimental model of an incident ocean wave interacting with an ice floe is used to validate the canonical, solitary floe version of contemporary theoretical models of wave attenuation in the ice-covered ocean. Amplitudes of waves transmitted by the floe are presented as functions of incident wave steepness for different incident wavelengths. The model is shown to predict the transmitted amplitudes accurately for low incident steepness but to overpredict the amplitudes by an increasing amount, as the incident wave becomes steeper. The proportion of incident wave energy dissipated by the floe in the experiments is shown to correlate with the agreement between the theoretical model and the experimental data, thus implying that wave-floe interactions increasingly dissipate wave energy as the incident wave becomes steeper.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2015GL065937

Sea ice floes dissipate the energy of steep ocean waves

Hydrodynamic responses of a thin floating disk to regular waves

The current study experimentally investigates the wave-induced drift velocity of two-dimensional large floating objects (with Lg/L>0.2, where Lg = longitudinal length of the floating objects, and L = wavelength) under the action of regular waves. The focus is on the high-precision measurement of drift behavior and a wider range of parameters than what was previously reported in the literature. Stacked wood pieces with various submergences (s) were used to simulate the large floating objects on the water surface. An infrared-based motion monitoring system with two high-resolution cameras continuously recorded their motion in regular waves. The results show that the drift velocity increased quickly from the beginning and reached a quasi-steady mean value. The magnitude of the quasi-steady drift velocity increased with ratio of the pitch period to the wave period (TR/T), until reaching a maximum when TR/T≈1. After that, further increasing the ratio of TR/T did not lead to additional significant chang...

https://www.earthobservatory.sg/files/publications/pdf/1-s2.0-S0029801810002854-main.pdf

Wave-Induced Drift of Large Floating Objects in Regular Waves

The Hong Kong–Zhuhai–Macau Link project crosses the ocean water of Ling Ding Yang and includes a 10 km long bridge section and a 6 km submerged tube tunnel section. The submerged tube tunnel is to be placed in the base trench at the seabed under 40 m water depth (d). Each tunnel element is 180 m in length, 11.4 m in height and weighs 72,000 tons in air. All tunnel elements are to be constructed on yards onshore, towed to the site location, linked to two stabilising floating pontoons and then ballasted and immersed at the site location with an exposed open wave environment. To ensure that the tunnel element can be immersed and then landed safely and accurately on the base trench during the process, an experimental study with scale model tests was performed to investigate the motion responses of the immersing tunnel element linked to the floating pontoons under random waves. The experimental measurements revealed quantitatively the motion behaviour under different wave climates, immersion depths and negativ...

Guoxing Huang

Papers

Wave-Induced Drift of Large Floating Objects in Regular Waves

Motion response of immersing tunnel element under random waves

Experimental study on motions of tunnel element during immersion standby stage in long wave regime

Experimental study on motion responses of a moored rectangular cylinder under freak waves (I: Time-domain study)

A novel method in generating freak wave and modulating wave profile