The Continuous Strength Method – Review and Outlook

Abstract

The Continuous Strength Method (CSM) is a deformation-based approach to the design of structures that enables a continuous, rational and accurate allowance for material nonlinearity. Central to the method is the application of strain limits to define the resistance of a structural member or system.The method can be applied to structures formed using different materials and manufacturing processes and can be used for steel-concrete composite design and in fire scenarios. The design method enables enhancements in structural efficiency and, unlike traditional approaches, allows the assessment of both strength and ductility demands (particularly relevant for high strength steel) at the ultimate limit state. For hand calculations, a set of straightforward CSM design equations have been developed. Recognising the increasing importance and use of advanced analysis, recent research, summarised herein, has focused on integration of the CSM strain limits into a framework of design by second order inelastic analysis, where the benefits of the method become even more substantial. This paper provides a review of the background and recent developments, including incorporation into design standards.