We develop a finite-element method for the simulation of dynamic fracture and fragmentation of thin-shells. The shell is spatially discretized with subdivision shell elements and the fracture along the element edges is modeled with a cohesive law. In order to follow the propagation and branching of cracks, subdivision shell elements are pre-fractured ab initio and the crack opening is constrain...

The demands by the semiconductors industry for high levels of integration, lower costs and a growing need for complete system solutions has led to the emergence of ”System In Package” (SIP) solutions in which ”the package is the system”. Since SIP-microsystems have multiple thin and stacked layers manufactured using different processes and materials, internal (intrinsic and/or thermal) mismatch...

Title: Crack Growth During Brittle Fracture in Compression. Author: Bartlett W. Paulding, Jr. Submitted to the Department of Geology and Geophysics February 9, 1965 in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology. Photoelastic analysis of several two-crack arrays predicts that compressive fracture is initiated at cra...

In the present study, plate-impact experiments are employed to better understand the stress threshold for inelasticity in Westerly granite. The experiments are designed to obtain the Hugoniot Elastic Limit (HEL) as well as spall strength following shock-induced compression in the Westerly granite samples. The HEL for Westerly granite is estimated to be in the range 3.2 to 3.5 GPa, while the spa...

We propose a theoretical model for branching instabilities in 2-dimensional fracture, offering predictions for when crack branching occurs, how multiple cracks develop, and what is the geometry of multiple branches. The model is based on equations of motion for crack tips which depend only on the time dependent stress intensity factors. The latter are obtained by invoking an approximate relatio...

In this work, the mechanism for fracture of brittle substances such as rocks under a uniform normal tension is considered. The oriented straight micro-cracks are mostly created in all the polycrystalline materials resulting from the stress concentrations. The present work focuses on the interactions of the pre-existing micro-cracks, which can grow and propagate within a rock-like specimen. The ...

Crack-like objects that propagate along frictional interfaces, i.e. shear cracks, play a major role in broad range of phenomena. Such cracks are commonly assumed to feature the universal square root near-edge singularity ideal as predicted by Linear Elastic Fracture Mechanics. Here we show this is not generic case due intrinsic dependence strength on slip rate, even if bodies forming interface ...

Observations of natural fractures in core or image logs typically give limited information on orientation, aperture and intensity. Because of the sparseness of wellbore intersections of fractures, data analysis results in incomplete statistical characterization of the fracture population, leaving interwell characterization almost impossible. Using basic fracture mechanics models and a novel cor...

Combining several materials to create a structural system has led to a new kind of application previously not possible with conventional materials. Examples are FRP and its strengthening system. Nonetheless, the existence of the interface between two substrates introduces a challenging problem in determining durability of bond systems. In many applications, the durability of individual material...