بررسي سرعت انتشار كمانش ديناميكي در خطوط لوله دريائي

INVESTIGATION INTO DYNAMIC BUCKLE PROPAGATION VELOCITY IN MARINE PIPELINES

A pipeline is considered as shell structure so its design is based on stability concepts; due to the exerted high pressure, local instability is probable to occur and so prevention of its occurrence and propagation are important subjects in its design. In this paper, dynamic buckle propagation has been modeled by 3D finite element method, results are verified with experimental tests and velocity of dynamic buckle propagation is calculated for pipes with different diameter to thickness ratios. Due to the effect of velocity in designing of marine pipelines, separate relations based 011 the initiation pressure are derived for the velocity of propagation and the influence of diameter to thickness ratio on the propagation velocity is studied. Keywords: Dynamic Buckle propagation, Hydrostatic pressure, Marine pipelines, Propagation velocity, Diameter to thickness ratio