Gruppelaar, Melle; Bele, Eral; Tan, PJ; (2025) Effects of buckling struts on the fracture toughness of triangular lattices. International Journal of Solids and Structures , 322 , Article 113627. 10.1016/j.ijsolstr.2025.113627.

Preview

Text Tan_1-s2.0-S0020768325004135-main.pdf Download (3MB) | Preview

Abstract

The effect of strut-buckling on the fracture toughness of elastic-brittle triangular lattices is investigated using the finite element method. Buckling of struts in the vicinity of a crack-tip is shown to precede fracture contingent on the relative density and strut material. Under idealised -field conditions, it was found that the buckling struts act as a toughening mechanism in Mode I loading and lead to a knockdown in fracture toughness in Mode II. Linear perturbation analyses reveal the transition relative density below which strut-buckling precedes fracture, and its dependence upon the fracture strain of the strut material. A power-law scaling relationship between fracture toughness and relative density is proposed for the regime where buckling of constituent struts can occur before fracture. It will be shown that strut-buckling can lead to elastic crack-tip blunting and to the development of compliant layers of cells with reduced stiffness. Subsequently, the effects of mode mixity and T-stress on the transition relative density and deviation from the traditional fracture toughness scaling law are addressed. Buckling struts act as a toughening mechanism in modes with predominantly Mode I influence and lead to a knockdown in toughness for modes with more than 25% Mode II contribution. The inclusion of negative T-stress leads to an increase in the transition relative density and to significant toughness knockdown after the onset of buckling in Mode I.

Download activity - last month

Export as JSONXMLCSV

Download activity - last 12 months

Export as JSONXMLCSV

Downloads by country - last 12 months

Export as XMLCSVJSON

Archive Staff Only

View Item