Theory edge loading

The two parameters that describe the refining process by the specific edge load theory are SEL or intensity of refining and specific refining energy (SRE) and these are defined below. 

There is a simple analytical solution, treating the cell edges as slender beams with a constant cross section. The deformed shape of the edge DC has a centre of symmetry at its midpoint O (Fig. 4.23). The half-edge shape is that of a cantilever beam of length L/2, built in at vertex C, loaded at its free end O by a force P/2. Large deformation beam theory relates the local curvature to the moment M by Eq. (C.15). The compressive stress cr in the... 

Specific surface load (SSL) theory is an extension of SEL theory and it assumes that the energy is transferred to the fibre bundles during the short edge-to-edge contact phase as well as during the edge-to-surface phase (Lumiainen, 1990). By combining these two, SSL is defined as shown in Equation (13.6), where Equation (13.7) holds ... 

It was noted in Section 2.3.2 that most of the current interfacial fracture mechanics methodologies describe steady-state crack propagation, but not the initiation of interfacial cracks. A recent approach to the prediction of initiation is based on the calculation of the singular stress field at the free edge of a bimaterial system loaded on the top layer [59,60]. Because the crack is assumed not to exist initially in this analysis, a very different singular field is predicted, and the results can be used to predict initiation of cracks in residually stressed coatings. Because the predictions of this theory sometimes contradict the predictions of the Suo and Hutchinson approach, we shall briefly review it as a final note. 

A failure theory which combines classical lamination theory with ffee-edge interlaminar stress was employed to predict the strength of laminates with free edges. Laminates studied were [ 0]2s angle-ply laminates, [ 0/9O]s laminates, and fiber-dominated 7t/4 laminates. The present theory was capable of predicting failure loads for [ 0]2s and [ 0/9O]s laminates as well as delamination on-set loads for 7t/4 laminates. 

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