Control Mechanisms of Stress Redistribution Locus in Structures

Dependency of results of structural analysis on constitutive equations obstructs the application of inelastic analysis methods to design. To overcome this difficulty, a realistic inelastic analysis approach assisted by the stress redistribution locus (SRL) has been proposed for the purpose of design application. The basis of this approach is the existence of an unique SRL in each structure. The final goal of this study is to assure the uniqueness of SRL. To clarify control mechanisms of SRLs in structures, elastic-plastic and elastic-creep behaviors of fundamental structures are analyzed. The first model is a stepped bar model subjected to a tension load. The second one is a stepped beam model subjected to a bending load. It is revealed that the elastic cores control SRLs in structures, therefore that SRLs are independent of constitutive equations. Structures with large elastic cores have steep SRLs because elastic cores constrict strain. When elastic cores are reduced, SRLs gradually change from steep to gentle as the constraint becomes weaker. Under bending load, elastic cores shrink to the neutral axis in the same way. Therefore, many structure mainly subjected to bending load have similar SRLs.