Estimating the effect of assumed initial damage to the hydraulic stability of pattern-placed revetments on dikes using finite element modeling

Initial damage, caused by previous wave loading or other events, might affect the hydraulic stability of pattern-placed revetments. Three common types of damage are considered in this study. The effect of this assumed initial damage on the hydraulic stability and failure probability of revetments is quantified using a FEM model. This model is...

Force and water jet impact reduction on adjacent structures by means of free surface breakwaters

In head waves, water jet impacts due to run up can occur as a result of the structural configuration of some floating structures, reducing workability. Wave attenuation near the floater may reduce the risk of water jet impacts. This paper presents a numerical study of the performance and attenuation mechanisms of various plate type fixed free...

Rocking of offshore lighthouses under extreme wave impacts: Limit analysis, analytic formulations and distinct element method

This study describes the structural response of historic lighthouses to extreme wave impacts. Located offshore on exposed rocks, 19th Century lighthouses were built with large interlocked granite blocks and have survived weathering for nearly two centuries. Under extreme wave impacts, lighthouses of this structural typology may uplift and...

Pulsed LED line light for large-scale PIV -development and use in wave load measurements

In this paper the development of a high-power pulsed LED line light and its use to apply particle image velocimetry (PIV) during wave impact measurements are described. An electrical circuit that generates high-current pulses is designed and built, which is used to overdrive a number of commercially available LEDs. The limit for this...

Experimental investigation of wave tip variability of impacting waves

We present an experimental study on the variation in wave impact location and present a mechanism for the development of free surface instabilities on the wave crest for repeatable plunging wave impacts on a vertical wall. The existence of free surface instabilities on an impacting wave is well known, but their characteristics and formation...

Effect of Venting Holes to Relieve Wave Impact Pressures on Flood Gates with Overhangs

Flood gates in storm surge barriers or outlet sluices can be prone to violent wave impacts. When an obstruction is present at the sea side above the gate, confinement of the incoming waves can lead to impulsive wave loads, even when the waves are non-breaking. The large loads can increase the stresses in the gate and structure considerably. One...

Use of impulses to determine the reaction force of a hydraulic structure with an overhang due to wave impact

This paper describes a method of determining the reaction forces of a vertical structure with an overhang to impulsive wave impacts. The aim is to develop a method to design a hydraulic structure exposed to the impulsive wave impact. At present, there is a lack of guidelines on the designing and verification with such a purpose. The impulse...

Summary of model tests on impact forces on Hanstholm breakwaters

Model investigation of wave forces on a caisson breakwater in Hanstholm, Denmark.