Mohammad Vaghefi

Submarine pipeline is one of the most popular research filed that many researchers focus on solving the issue of buckling of pipeline. The snaked laying is an effective method to control the lateral buckling. The scour below offshore pipeline may affect the efficiency and performance of the snake lay pipeline. The objective of this study was to investigate the effect of scour hole on the buckling of seawater pipelines. A three-dimensional numerical model developed to investigate the effect of scour below offshore pipeline subjected to wave and current by using Abaqus software and Aqua Module. The results indicated that vertical deformation of straight pipeline increased by increasing scour hole depth. This value changed 4.85 cm to 32.87 for holes 11 to 200 cm respectively, but these parameters of the snake lay pipelines were not affected by the presence of scour hole. Moreover, the effective axial force of snacked lay pipelines reduced 5 times in comparison to straight pipeline by applying wave and current. The results indicated that the value of stress of snaked-lay pipeline was independent on scour hole depth. Therefore, this pipeline was effective method to limit and control buckling even in the presence of scour below it.