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Peridynamic theory was first introduced by Dr. S. A. Silling at Sandia National Laboratories, USA, in the year of 2000. It is a state-of-the-art technique which is relatively new and promising tool [1]. It is basically re-formulation of classical continuum mechanics theory introduced by A. L. Cauchy more than 200 years ago. The volumetric integral, which does not include spatial derivatives, is used in its formulations.

Prediction of fracture and failure is a challenging research area. There are various methods available in the literature for this purpose including well-known finite element (FE) method. FE method is a powerful technique for deformation and stress analysis of structures. However, it has various disadvantages in predicting failure due to its mathematical structure since it is based on classical continuum mechanics (CCM). CCM has governing equations in the form of partial differential equations. These equat ions are not valid if the displacement field is discontinuous as a result of crack occurrence. In order to overcome this problem, a new continuum mechanics formulation was introduced and named as Peridynamics [1] . Peridynamics uses integrals equations as opposed to partial different equations of CCM. Moreover, it does not contain any spatial derivatives. Hence, its equations are always valid regardless of discontinuities. In this presentation, the applications of Peridynamics for marine structures will be demonstrated. Particularly, the Peridynamic equations are rederived for simplified structures commonly used in marine structures including beams and plates. Furthermore, underwater shock response of marine composites is investigated. Finally, the peridynamic formulation for contact analysis which can be used for collision and grounding of ship structures will be demonstrated. In order to reduce the computational time, several solution strategies will be explained including parallel programming applications.

The moisture concentration in electronic packages can be determined based on the “wetness” approach. The wetness parameter representing the ratio of the moisture concentration with respect to the saturated concentration value of the material is continuous along dissimilar material interfaces. If the saturated concentration value is not dependent on temperature or time, the wetness equation is analogous to the standard diffusion equation whose solution can be constructed by using any commercial finite element analysis software. However, the time dependency of saturated concentration requires special treatment under temperature dependent environmental conditions such as reflow process. The saturated concentration values of most polymer materials in electronic packages are mostly dependent on temperature. As a result, the wetness equation is not directly analogous to the standard diffusion equation. This study presents peridynamic solution of the wetness equation with time dependent saturated concentration. The approach is computationally efficient as well as easy to implement without any iterations in each time step. The implementation is achieved by using the traditional elements and solvers available in a commercial finite element software.