Inclusion of intermediate partial constraints in piping flexibility analysis—A general approach

Abstract

Flexibility analysis of pipelines is fairly established and computerised, and many commercial softwares are available for this purpose. However, no method has yet been developed to unite intermediate partial constraints into the body of the equilibrium equation of the piping system. The available methods tackle the intermediate partial constraints by somehow improving the equilibrium equations and/or results. This paper describes a very general approach to piping flexibility analysis incorporating intermediate partial constraints. The method admits all types of intermediate partial constraints to be imposed simultaneously upon any node of the structure, such that some degrees of freedom of a node may be restrained by springs, some by external forces and some could be suppressed rigidly. The method, unlike all others, obtains the proper matrix equilibrium equation of the whole piping system. It is particularly suited for automatic computation.