Stability and strength of steel silo transition junctions

A sophisticated experimental facility was developed as a multi-purpose test rig for shell buckling experiments with special attention to the testing of steel silo transition junctions. This facility included a loading frame, a rotating measurement frame supporting a laser displacement meter for accurate geometric imperfection and deformation surveys, and necessary equipment for the fabrication of quality test models from thin steel sheets.; The experimental program of the present study consisted of three series of tests: the CC series on cone-cylinder junctions under internal pressure, the CCS series on cone-cylinder-skirt junctions under bulk solid loading and the CCSR series on cone-cylinder-skirt-ring junctions under bulk solid loading.; Four tests were carried out in the CC series, with one of them being a ring-stiffened cone-cylinder junction. These tests not only provide useful data for calibrating numerical models of steel shell junctions without the uncertainty associated with bulk solid loading, but also address a buckling problem of importance to the design of pressure vessel and piping components. A rational finite element model established through these numerical simulations was then deployed in a parametric study on cone-cylinder junctions covering a wide range of geometry. A design proposal in the Eurocode format is proposed for practical use.; The tests of the CCS series represent the first investigation into buckling in transition junctions which do not feature a ring. The CCSR series consisted of five tests and is the first experimental study on cone-cylinder-skirt-ring junctions in steel silos. Geometric imperfections and deformations are presented and interpreted by Fourier decomposition to study the development of buckling deformations. Development of strains and failure modes are carefully examined. For junctions with a ring, methods for the determination of experimental buckling loads based on displacement measurements on the ring are presented.; Nonlinear bifurcation buckling analyses were carried out for model silo transition junctions using the nominal perfect geometry. Both the buckling loads and the buckling modes are compared to experimental results. Nonlinear analyses were also performed using both measured and eigenmode-affine imperfections. The effects of a number of factors on the load carrying behaviour of transition junctions are investigated, including the distribution of pressure in the model junction, the effect of welding on yield stress, and the welding deposit at the transition. The effect of ring/junction buckling on the load carrying capacity of transition junctions and the imperfection sensitivity of these junctions are also examined. (Abstract shortened by UMI.)...