Constitutive laws are mathematical models used to explicitly describe the behavior of materials. These material-specific laws can be data driven (i.e., phenomenological-based constitutive models) or constrained by the microstructural-level interactions in the material (i.e., structural constitutive models). This talk highlights these two approaches to understand anisotropic, nonlinear mechanical behavior of vascular and musculoskeletal tissues. In the first approach, jugular vein-derived tissues implicated in diseases ranging from venous hypertension to venous valve incompetence are modeled by adopting a suitable strain energy function via constant invariant mechanical testing, followed by additional biaxial testing to estimate parameters of the constitutive relations. Such models can support the development of continuum models required for numerical analyses and simulations of fluid–structure interactions. In the second approach, the tendon-to-bone insertion tissue (i.e., the enthesis), a graded connective tissue whose anisotropic biomechanical functions depend intimately on the regional biochemical composition and structure, is modeled by adopting the nonlinear anisotropic Gasser-Ogden-Holzapfel model. Collagen fiber orientations and dispersions, as well as mineral concentrations, are included in this structural-based computational model. The in-silico models are verified by comparing to the in-situ biaxial mechanical testing results, thereby serving as translational tools for accurately predicting the material behavior of the tendon-to-bone insertions.
Dr. Huang is an Associate Professor in Mechanical and Aerospace Engineering (Primary) and in Biomedical Engineering (Courtesy). She is also an Associate Director of the Analytical Instrumentation Facility and a faculty member of Comparative Medicine Institute at NC State. She was trained at the University of Pittsburgh (MS & PhD in Mechanical Engineering and Materials Science). Prior joining NC State in 2010, she was a Postdoctoral Associate at MIT. At NC State, Dr. Huang teaches and conducts research in the areas of mechanics of materials, non-equilibrium thermodynamics, continuum mechanics and nonlinear elasticity. Dr. Huang’s research programs are centered on understanding the mechanics of cardiovascular, musculoskeletal tissues, and energy materials. Dr. Huang was the Chair of ASME Nanomaterials for Energy Technical Committee from 2013-2015 and a Guest Editor of the ASME Journal of Nanotechnology in Engineering and Medicine in 2014-2015. Dr. Huang is a NSF CAREER award recipient in 2016. Dr. Huang was selected as a 2017 Doctoral Mentoring Fellow at NC State to promote cross-cultural mentoring for underrepresented groups. Additional information can be found at: https://huang.wordpress.ncsu.edu/