In this paper, we’ll answer several abstract, formal questions about the nature of crack growth and nucleation. Bringing a field theory point of view to fracture illuminates things in what I hope will be an entertaining way. Formally, what is the crack nucleation rate? Fracture is an instability of elastic theory under tension. For thermally nucleated cracks, there is an analogy with supercoole...

This is the second in a series of two papers generated from a study on probabilistic meshless analysis of cracks. In this paper, a stochastic meshless method is presented for probabilistic fracture-mechanics analysis of linear-elastic cracked structures. The method involves an element-free Galerkin method for calculating fracture response characteristics; statistical models of uncertainties in ...

In the present paper, computations of mixed mode stress intensity factor (SIF) variations along the crack front, and fatigue-crack-growth simulations, in cracked I-beams, considering different load cases and initial crack configurations, are carried out by employing the three-dimensional SGBEM (Symmetric Galerkin Boundary Element Method)–FEM (Finite Element Method) Alternating Method. For mode-...

The present paper discusses the results of an investigation into the effects of test rate and the mode of loading on the fracture energy, Gc, of adhesively-bonded fibre-composite joints. Various carbon-fibre reinforced-polymer (CFRP) matrix composite substrates have been bonded using two different types of automotive structural epoxy-adhesives. They have been tested via loading the bonded joint...

Crack growth along an interface joining an elastic-plastic solid to a solid that does not yield plastically is studied numerically, accounting for mixed mode loading under conditions of small scale yielding. The fracture process is represented in terms of a cohesive zone model, for which the work of separation per unit area and the peak stress required for separation are basic parameters; but w...

A cohesive element formulation is proposed that provides a general framework to approximate experimentally measured Traction–Separation Law (TSL) shapes. Unlike other approaches, it does not assume specific TSL shapes, such as bi-linear or exponential. The shapes are defined generally, in piecewise-linear fashion, and Mode I shear (Mode II III) TSLs can have different Furthermore, added general...

The size effect in the failure of a hybrid adhesive joint of a metal with a fiber-polymer composite, which has been experimentally demonstrated and analytically formulated in preceding two papers, is here investigated numerically. Cohesive finite elements with a mixed-mode fracture criterion are adopted to model the adhesive layer in the metal-composite interface. A linear tractionseparation so...