Mechanical behaviour in tension of cracked glass bridged by an elastomeric ligament

Mechanical behaviour of cracked glass bridged by an elastomeric ligament is central to properties of cracked glass/polymer laminates and other composites. We present a theoretical and experimental study of a glass/polymer/glass laminate with single aligned cracks in each glass plate, subjected to tensile loading. The test involves stable delamination at the interface between the polymer and substrate. The force required to maintain increasing strain rises to a steady state value. Crack propagation is accompanied by large polymer deformation. The polymer has been modeled as an isothermal hyperelastic material. Exact results in the limit of large crack extension relate the steady-state force to a measure of interfacial fracture energy and elastic material properties. These have been used to extract glass/polymer adhesion from experimentally measured steady-state force. Force-displacement relationships have also been derived for the limiting case of small crack lengths. Together, the results represent a force-displacement model for a cracked glass/polymer laminate, which can be used to build models for multiply cracked laminates. Finite element simulations of the experiment using cohesive elements to model the interface have been used to model the entire force-displacement response.