The Dynamic Response of a 3D Mussel Dropper in Waves: The construction of a 3D numerical model for a series of connected pendulums

Offshore mussel cultivation is gaining popularity, with the longline technique emerging as a popular method for cultivation. The longline technique entails multiple backbones from which mussel lines that loop around it are suspended and which are kept afloat by buoys. Overdulve Offshore Services designed the Cees Leenaars, a semi-submersible...

Characteristics of ice-structure-soil interaction of an offshore wind turbine

This research investigates the dynamic response of offshore wind turbine (OWT) systems subject to ice-structure-soil interaction (ISSI). To simulate the behavior of level ice sheets, a coupled approach involving the cohesive element method (CEM) and the finite element method (FEM) is applied. For soil-structure interaction (SSI), the Mohr...

Wave Induced Dynamics of Offshore Heavy Lift Cranes on Jack-Ups: Analysis of the annual probability of failure of the crane in normal operation

Due to the increasing size of offshore wind turbines, the jack-up vessels and cranes installing them need to increase in size. The increase in length of the crane boom results in an increase of the dynamic response of the crane. This increase in response results in higher loads in the crane. The magnitude of the higher loads are unknown and not...

Long-term rogue wave occurrence probability from historical wave data on a spatial scale relevant for spar-type floating wind turbines

Very large waves, such as rogue waves, can be dangerous for ships and offshore structures. There is no consensus on the theoretical occurrence probability of these rogues and ocean measurements containing rogue waves are rare. This paper addresses the long-term occurrence probability of rogue waves using time-extreme (TE) and space–time...

Numerical prediction of the dynamic properties of a historic masonry structure: A Case Study of The Old Church in Garrelsweer, Groningen

The gas production in the Groningen gas field of the Netherlands has caused a significant amount of shallowhuman induced earthquakes. Among various building typologies, Groningen is home to many Dutch historical churches constructed by unreinforced masonry which has shown to be highly vulnerable to these earthquakes. From the perspective of...

Combined effects of elevated temperatures and high strain rates on compressive performance of S30408 austenitic stainless steel

This paper presents an experimental investigation on the dynamic mechanical performance of S30408 austenitic stainless steel (ASS) under elevated temperatures, which is essential for determining the behaviour of structures made with this type of steel subjected to the coupled fire and impact/explosion. For this purpose, the quasi-static and...

The impacts of internal solitary waves on a submerged floating tunnel

The interaction between an oceanic internal solitary wave (ISW) and a prototype submerged floating tunnel (SFT) is numerically investigated. Effect of oceanic internal solitary wave amplitude, the relative distance of the SFT to the pycnocline, cross-sectional geometry of the SFT, and the density ratio of the two fluid layers are analyzed. At...

Corrected method for scaling the dynamic response of stiffened plate subjected to blast load

Test on a small scaled model is an effective approach to predict the dynamic response of full scale structure under blast loadings. However, the geometric dimensions of specimens cannot simply comply with complete geometrical similarity due to manufacture or test restrictions. It would result in the difference structural performance between...

Observation and interpretation of closely spaced fundamental modes of a high-rise building

In this paper the dynamic behaviour of a high-rise building with complex structural system is studied. In some cases, to optimize the building design, the horizontal stability of the building is accomplished by the contribution of several structural components. This is the case of the JuBi tower, the building studied in this paper. The...

Macro-meso dynamic analysis of railway transition zone: Hybrid DEM/FDM simulation and experimental validation

To probe into the mechanical behaviour of railway transition zone from the macro-meso aspects, a numerical model of transition zone is built that hybrids the Discrete Element Method (DEM) and Finite Difference Method (FDM). The DEM is utilised to simulate the ballast bed and sleeper, because it can consider the realistic ballast shapes and...

Dynamic analysis of layered systems under a moving harmonic rectangular load based on the spectral element method

In order to design high-performance roadways, a robust tool which can compute the structural response caused by moving vehicles is necessary. Therefore, this paper proposes a spectral element method-based model to accurately and effectively predict the 3D dynamic response of layered systems under a moving load. A layer spectral element and a...

Dynamic ice actions in the revision of ISO 19906

The second edition of the ISO19906 design standard contains changes in the informative appendix concerning dynamic ice actions. Challenges in application of the previous approach and advances in understanding of the dynamic ice-structure interaction process were the main motivation for the revision. The new guideline provides relevant...

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...

Statistical properties of atmospheric turbulence relevant to the calculation of airplane loads

Measured time histories of atmospheric turbulence have been analysed. Distribution functions and exceedance curves of the turbulence and its derivative are presented. The load exceedance curves of various mathematical airplane models due to these turbulence patches have been calculated. Deviations of the properties of these patches from the...

Axisymmetric liquid sloshing under low-g conditions: numerical simulations method (-reference manual-)

A mathematical model is presented for the description of axisymmetric three-dimensional transient flow of a viscous liquid in a partially filled cylindrical container under low gravity conditions. The mathematical model consists of the Navier-Stokes equations with either no-slip condition at the solid boundaries, and with the continuity of...

NLR Contributions to the flutter certification of aircraft with external stores

An outline is given of store flutter clearance activities of the NLR carried out by order of the Royal Netherlands Air Force. Special attention is devoted to the store flutter clearance of the F16 aircraft. Presented at: 7th Aircraft/Stores Compatibility Symposium,Wright-Patterson AFB, Ohio, 8-10 April 1986 and at the 17th Annual Symposium of...

Review and comparison of discrete and continuous gust methods for the determination of airplane design loads

Historical reviews of the discrete gust and the continious gust concept, in relation to the present requirements, are given in this report. A comparison is made between the discrete gust method and the power spectral density method on the basis of simple airplane models. No direct relation between the two methods exists. The main cause of the...

A method for applying linear optimal control theory to the design of a regulator for a flexible- aircraft

This report deals with determining a hypothetic control system which provides improved rigid body and structural mode damping of a flexible aircraft in order to improve the riding qualities and to minimize the wing bending moment during flights in turbulence. The equations of motion used in the computations are related to a high' performance...