Virtual crack closure technique: History, approach, and applications

Abstract

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A damage model for the simulation of delamination in advanced composites under variable-mode loading

“…After delamination onset, LEFM can be used to predict delamination growth [3]- [4]. Techniques such as virtual crack closure technique (VCCT) [5]- [9], J-integral method [10], virtual crack extension [11] and stiffness derivative [12] have often been used to predict delamination growth.…”

Advanced numerical modelling techniques for the structural design of composite tidal turbine blades

“…Numerical analysis techniques include the Virtual Crack Closure Technique (Rybicki and Kanninen, 1977;Krueger, 2004) and the use of interface elements, which are specialised finite elements placed along potential failure planes and used to simulate crack growth (Camanho et al, 2003;Jiang et al, 2007;Hallett, 2007). A key advantage of interface elements is that they can encompass both strength based damage initiation criteria and fracture based crack propagation criteria.…”

Damage tolerance optimization of composite stringer run-out under tensile load

“…Krueger [23] proposes some guidelines about mesh size for the correct application of the VCCT (Section 2.2) in composite materials. The authors performed a sensitivity analysis concerning the dependence of the total energy release rate (G) on the element length (△a).…”