Modeling of crashworthy composite structures is limited by the inability of current generations of finite element crash codes to effectively model certain critical failure modes, such as delamination. Previous efforts to model delamination and debonding failure modes using crash codes have typically relied on ad hoc failure criteria and quasistatic fracture data. Improvements to these modeling ...

A concept of "Fractal Fracture Mechanics" for HDR .(Hot Dry Rock) geothermal reservoir design has been developed as an extension of conventional rock fracture mechanics. It is suggested that this concept is successfully applicable to characterize and model subsurface fracture network in HDR geothermal reservoir. Furthermore, this modeling procedure makes it possible to evaluate the thermal ener...

Bone fracture is a very common body injury. The healing process is physiologically complex, involving both biological and mechanical aspects. Following a fracture, cell migration, cell/tissue differentiation, tissue synthesis, and cytokine and growth factor release occur, regulated by the mechanical environment. Over the past decade, bone healing simulation and modeling has been employed to und...

We present a three-dimensional modeling study of gas flow in the unsaturated fractured rock of Yucca Mountain. Our objective was to estimate large-scale fracture permeability, using the changes in subsurface pneumatic pressure in response to barometric pressure changes at the land surface. We incorporate the field-measured pneumatic data into a multiphase flow model for describing the coupled p...

Effectiveness of cutting is measured by the ability to achieve a desired rate of material fracture. The work performed by a knife overcomes the material toughness to yield fracture, acts against friction between the material and the blade, and generates shape deformation. This paper studies how to control a robotic arm to achieve a desired time profile of material fracture along a prescribed cu...

Reduced-order modeling approaches for gas flow in dual-porosity dual-permeability porous media are studied based on the proper orthogonal decomposition (POD) method combined with Galerkin projection. The typical modeling approach for non-porous-medium liquid flow problems is not appropriate for this compressible gas flow in a dual-continuum porous media. The reason is that non-zero mass transfe...

Ductile fracture modeling still has to be improved at the macro and microscales. New numerical methods are applied to the limit analysis of cells containing one or several voids or void clusters. The results are compared with existing macroscopic models. Voids can also be introduced in analytical polycrystalline models, in order to combine plastic anisotropy and texture evolution with ductile f...