... ABSTRACT Lufeng 15-1 platform locates in South China Sea. The average water depth at the platform site is 286m, and there are large sand waves distributed in latticed and crescent shape. The uneven seabed topography introduces great challenges to jacket on-bottom design. In order to avoid...

... drag coefficient coefficient fluid dynamics topography sand wave topography evolution underwater vehicle sand wave seabed topography lift coefficient wave crest continuous sand wave viscous drag coefficient total drag coefficient pressure distribution contour pressure drag...

... offshore pipeline onset span length lf14-4 dpp weld root span length assessment operation condition frequency upstream oil & gas fatigue damage residual lay tension dnvgl-rp-f105 maximum lay tension midstream oil & gas lay tension sand wave weld cap viv onset span length...

... route layout in offshore wind farms are only based on a flat seabed and do not take the seabed dynamics into account. For offshore wind farms, migrating seabed features in the form of sand waves are of great importance and may significantly alter the position of the seabed over the life time of the wind...

... Abstract A morphological model to predict the formation of tidal dunes (sand waves) and their migration is described. The analysis assumes that the appearance of the bedforms is due to the growth of the most unstable component of an initially random perturbation of small amplitude, forced...

... depth change characteristic depth distribution kanmon waterway cross section average depth depth change characteristic route boundary sand wave artificial intelligence seto inland sea mean depth tanoura depth change speed boundary time series strait Depth Change...

... pipeline lateral buckling. This paper discusses the integrated free span/lateral buckling mitigation scheme successfully designed and implemented for the Lan Do Flowline. allowable span length intervention work upstream oil & gas sand wave area span coral carbonate outcrop lateral movement...

... ABSTRACT: The subsea tieback routes of the Medway Field Development cross a mobile seabed with large sand waves and numerous megaripples. To allow the pipelines to be laid, without excessive free spanning, two lay corridors were pre-swept using a Trailing Suction Hopper Dredger (TSHD...

... are successfully predicted. INTRODUCTION The sand waves, with wavelengths from tens of meters to kilometers and heights of several meters, can be found in many sandy shallow seas. Unlike static sand ridges and sandbanks, the sand waves often migrate with speed of up to some tens of meters per year (Nemeth et al...

... into the Shallow water area, Sand wave and Sand ridge area and the Deep water area according to the seabed terrains. The spanning mechanisms of the pipeline in the routing areas are mainly as follows: submarine differential erosion, the movement of sand waves, the interaction of sand waves and grooves, the piping...

... of seabed mega-ripples. Of particular interest is how the drag force and trench geometry are affected. Information was achieved by conducting a series of reduced scale laboratory tests using a 1/50th scale model plough. A parametric study revealed that the wavelength and amplitude of the sand waves...

... ABSTRACT In a coastal environment, calculating the speed of sand waves is a challenge for engineers due to the complexity of the hydrodynamics and the variety of the governing phenomena. As the wave or wave-current propagates over wavy beds, the flow is fully complicated and involves regions...

... ABSTRACT Large parts of shallow seas are covered by regular seabed patterns and sand wave is one kind of these patterns. The instability of the sedimentary structures may hazard pipelines and the foundations of offshore structures. In the last decade or so, it's a focus for engineers...