ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at firstname.lastname@example.org.
- 4 English
- 4 Public
- 4 Mechanical engineering
- 2 Fracture
- 1 Anisotropic Materials
- 1 Composite material
- 1 Computational solid mechanics
- 1 Digital Image Correlation
- 1 Elasticity
- 1 Engineering
- 1 Extended finite element
- 1 Geometry representation
- 1 Geometry segmentation
- 1 Lattice Spring Model
- 1 Microstructurally explicit finite element model
- 1 Nonlocal Potential
- 1 Polycrystalline Materials
- 1 closure
- 1 cohesive zone modeling (CZM)
- 1 deformation/failure mechanisms
- 1 fatgiue crack
- 1 fracture
- 1 kink bands in polymer matrix composites (PMC)
- 1 negative stress ratio
- 1 small time scale
- 1 stress gradients
Fracture phenomena have been extensively studied in the last several decades. Continuum mechanics-based approaches, such as finite element methods and extended finite element methods, are widely used for fracture simulation. One well-known issue of these approaches is the stress singularity resulted from the spatial discontinuity at the crack tip/front. The requirement of guiding criteria for various cracking behaviors, such as initiation, propagation, and branching, also poses some challenges. Comparing to the continuum based formulation, the discrete approaches, such as lattice spring method, discrete element method, and peridynamics, have certain advantages when modeling various fracture problems due to their intrinsic characteristics …
- Chen, Hailong, Liu, Yongming, Jiao, Yang, et al.
- Created Date
The objective of this research is to develop robust, accurate, and adaptive algorithms in the framework of the extended finite element method (XFEM) for fracture analysis of highly heterogeneous materials with complex internal geometries. A key contribution of this work is the creation of novel methods designed to automate the incorporation of high-resolution data, e.g. from X-ray tomography, that can be used to better interpret the enormous volume of data generated in modern in-situ experimental testing. Thus new algorithms were developed for automating analysis of complex microstructures characterized by segmented tomographic images. A centrality-based geometry segmentation algorithm was developed to …
- Yuan, Rui, Oswald, Jay, Chawla, Nikhilesh, et al.
- Created Date
Polymer matrix composites (PMCs) are attractive structural materials due to their high stiffness to low weight ratio. However, unidirectional PMCs have low shear strength and failure can occur along kink bands that develop on compression due to plastic microbuckling that carry strains large enough to induce nonlinear matrix deformation. Reviewing the literature, a large fraction of the existing work is for uniaxial compression, and the effects of stress gradients, such as those present during bending, have not been as well explored, and these effects are bound to make difference in terms of kink band nucleation and growth. Furthermore, reports on …
- Patel, Jay K., Peralta, Pedro D, Oswald, Jay, et al.
- Created Date
A previously developed small time scale fatigue crack growth model is improved, modified and extended with an emphasis on creating the simplest models that maintain the desired level of accuracy for a variety of materials. The model provides a means of estimating load sequence effects by continuously updating the crack opening stress every cycle, in a simplified manner. One of the significant phenomena of the crack opening stress under negative stress ratio is the residual tensile stress induced by the applied compressive stress. A modified coefficient is introduced to determine the extent to which residual stress impact the crack closure …
- Venkatesan, Karthik Rajan, Liu, Yongming, Oswald, Jay, et al.
- Created Date