title: Barnacles resist removal by crack trapping.
abstract: We study the mechanics of pull-off of a barnacle adhering to a thin elastic layer which is bonded to a rigid substrate. We address the case of barnacles having acorn shell geometry and hard, calcarious base plates. Pull-off is initiated by the propagation of an interface edge crack between the base plate and the layer. We compute the energy release rate of this crack as it grows along the interface using a finite element method. We also develop an approximate analytical model to interpret our numerical results and to give a closed-form expression for the energy release rate. Our result shows that the resistance of barnacles to interfacial failure arises from a crack-trapping mechanism.
authors.affiliation: Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA. ch45@cornell.edu
authors.forename: Chung-Yuen
authors.initials: CY
authors.lastname: Hui
authors.forename: Rong
authors.initials: R
authors.lastname: Long
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Wahl
authors.forename: Richard K
authors.initials: RK
authors.lastname: Everett
mesh_terms: D000268:Adhesiveness; D000818:Animals; D001696:Biomechanical Phenomena; D020724:Elastomers / Q000737:chemistry; D020342:Finite Element Analysis; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008954:Models, Biological; D001468:Thoracica / Q000033:anatomy & histology / Q000378:metabolism* / Q000502:physiology*
chemical_list: D020724:Elastomers; D008562:Membrane Glycoproteins; C048022:substrate adhesion molecules