Interactive Buckling Tests of Externally Pressurized Stiffened Bent Pipelines

Abstract:

The paper reports an experimental study on the collapse of long uniformly pressurized ring-stiffened bent pipelines. Bending in the presence of external pressure is experienced by pipelines during their installation and operation. The buckling aptitude of shells is dependent on two leading geometric ratios, i.e. the length to radius and radius to thickness. In this paper, four different ring-stiffened steel pipeline specimens were tested to collapse. The evolution of the specimens behavior that has been recorded in the presence of a uniform external pressure is outlined. A thin-walled pipeline is sensitive to buckling phenomena when it experiences locally a compressive stress. It is often considered that its behavior under bending is rather similar to pure compression, but very few are the experimental investigations that precise the real behavior of it. A comparison of experimental data to empirical formulae and design recommendations is finally achieved. Consequently, it has been found that with using ring stiffeners the structure behavior against the combination of loads is improved in all loading paths. Also it has been found that buckle propagation in all manners occurs suddenly and dynamically and the amount of initial bending moment is not serious in defining the number of buckling modes. Also, the considerable effects of a longitudinal spot weld line on the buckling strength and mode shapes are verified.

• Periodical: Key Engineering Materials (Volume 553)
• Pages: 103-109
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.553.103
• Online since: June 2013
• Authors: V. Hoseinzadeh, H. Showkati
• Keywords: Bending, Buckling, Pipeline, Ring-Stiffened, Uniform External Pressure

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DOI: 10.3850/978-981-08-9247-0_rp089-icsas11