Experimental path-following of equilibria using Newton's method. Part II: Applications and outlook. (15th March 2021)

• Record Type: Journal Article
• Authors: Shen, J.; Groh, R.M.J.; Schenk, M.; Pirrera, A.
• Is Part Of: International journal of solids and structures. Volume 213(2021)
• Page Start: 25
• Page End: 40
• Publication Date: 2021-03-15
• Subjects: Experimental Newton's method -- Nonlinear structures -- Virtual testing -- Stability -- Bifurcations; Mechanics, Applied -- Periodicals; Structural analysis (Engineering) -- Periodicals; Elastic solids -- Periodicals; Mécanique appliquée -- Périodiques; Constructions, Théorie des -- Périodiques; Solides élastiques -- Périodiques; Elastic solids; Mechanics, Applied; Structural analysis (Engineering); Periodicals; 624.18
• DOI: 10.1016/j.ijsolstr.2020.11.038
• Languages: English
• ISSNs: 0020-7683

Abstract

Highlights: Implement advanced experimental path-following for analysis of critical points. Developed virtual testing environment to demonstrate advanced functionalities. Experimental design for validation of classical FE benchmark model with rich nonlinearity. Propose efficient testing for shape-adaptive morphing structures. Propose novel non-destructive testing of thin-walled cylinder. Abstract: In Part I of this paper, a quasi-static experimental path-following method was developed that uses tangent quantities in a feedback controller, based on Newton's method. The ability to compute an experimental tangent stiffness opens the door to more advanced path-following techniques. Here, we extend the experimental path-following method to: (i) pinpointing of critical points (limit and branching points); (ii) branch switching to alternate equilibrium paths; and (iii) tracing of critical points with respect to a secondary parameter. We initially explore these more advanced concepts via the virtual testing environment introduced and validated in Part I. Ultimately, the objective is to demonstrate novel testing procedures and protocols made possible by these advanced experimental path-following methods. In particular, three pertinent examples are discussed: (i) design sensitivity plots for shape-adaptive morphing structures; (ii) validation of nonlinear FE benchmark models; and (iii) non-destructive testing of subcritical (unstable) buckling of thin-walled shells.