Linear elastic buckling of ring-stiffened cylindrical shell

5th Nov 2020

Buckling is one of the most important failure modes to consider in pressure vessel design as it can lead to a sudden and catastrophic collapse.  The animation below shows the first buckling mode obtained from a linear elastic buckling analysis of a ring-stiffened cylindrical shell subject to external pressure.   Overall collapse of the structure is predicted principally because of the short shell bay length and slender stiffeners used.

 

The bifurcation buckling load is determined by constructing a linear elastic stiffness matrix and geometric stiffness matrix.  Although this type of analysis almost always provides an overestimate of the real-world buckling load, a reasonable prediction of the actual buckling load can be obtained using a design factor depending on the requirements of the chosen design code.  The linear elastic buckling analysis method offers a fast, low cost solution, as the smallest eigenvalue returned can offer a quick indication as to whether the structure will be stable under the required service conditions.  It can also be used to highlight the regions of a structure in which stability issues could occur, as well as drawing attention to meshing irregularities that can themselves produce unexpected behaviour.  Linear elastic buckling analysis does have inherent limitations, however.  Due to being geometrically linear, the method can be a poor predictor of the importance of geometric imperfections.  It also cannot take material nonlinearity into account, although this isn’t necessarily an issue if the applied loading doesn’t result in any appreciable yielding.

In situations where linear elastic buckling analysis is deemed unsuitable, non-linear buckling analysis can be used. In this type of analysis the load is applied in a series of steps and, as the load is increased, the shape and, in turn, the stiffness of the structure changes, resulting in a solution that accounts for geometry and material nonlinearity.   Although such analyses are much more time consuming and expensive to run, with careful attention to material property definition and use of actual geometry, very accurate predictions of buckling load can be achieved.

News Archive

2021

Sizewell C Consortium - Build British Nuclear

20th Sep 2021

Delighted to hear this morning that we have been accepted as a member of the Sizewell C ... Read More

Meet the Team - Roger Bamberough

15th Sep 2021

Although he originally joined us on a short-term contract our Management Support Officer, Roger Bamberough, has been ... Read More

Meet the Team - Ross Hartwig

14th Jul 2021

Many people in the pressurised equipment industry will know the FINGLOW ... Read More

Our New Website

9th Jun 2021

We'd like to take this opportunity to thank Clive Major and George Hering at Ibis Marketing Ltd, ... Read More

Another job well done

7th Jun 2021

We're really pleased to have played a key part on this project by substantiating the entire pressure boundary ... Read More

Simultaneous build of three submarine rescue vehicles

4th Jun 2021

Still lots of work to do but we're really proud to be working with JFD on these ... Read More

Congratulations

2nd Mar 2021

Congratulations to Michael Travers, our new Mechanical Engineering Intern, ... Read More

Spring has sprung at Beane Bridge House

1st Mar 2021

So good to see the ... Read More

2020

Linear elastic buckling of ring-stiffened cylindrical shell

5th Nov 2020

Buckling is one of the most important failure modes to consider in pressure vessel design as it can ... Read More

New Member of Staff

9th Sep 2020

We are delighted to announce that we will be welcoming a new member of staff to our ... Read More

A view inside Australia's rescue submarine

29th Jun 2020

An excellent opportunity to have a look around inside LR5.   This was the first rescue submarine project ... Read More

Celebrating 25 years of excellence

10th Jun 2020

2020 is our 25th year in business. 

In recognition of this we have created an advert (see below) ... Read More

2019

Business as Usual

20th Nov 2019

Finglow Consultants Limited have recently taken on a new long term lease of the office premises at ... Read More

Stanlow Oil Refinery Time-Lapse

16th Sep 2019

Some time ago now but this video is well worth a watch.  We designed the entire cyclone ... Read More

View all News