Comparison of Experimental and Simplified Analytical Results for the In-Plane Plastic Bending and Buckling of an Elbow

Abstract

Predictions obtained from a simplified finite element analysis are compared with experimental results on the plastic in-plane bending and buckling of a 16-in-dia Type 304 stainless steel piping structure which consists of a 90-deg elbow and two straight tangent pipes. The large displacement analysis is based on the widely used MARC pipe-bend element 17, and on a stress-strain curve obtained from coupon specimens taken from the tested elbow. The simplified analysis predictions are found to be in reasonably good agreement with the experimental results. The analysis underestimates the experimental buckling load by 10 percent and overestimates the deformation at a given load, particularly at the higher load levels.