Modeling initial strain distribution in soft tissues with application to arteries.
A general theory for computing and identifying the stress field in a residually stressed tissue is presented in this paper. The theory is based on the assumption that a stress free state is obtained by letting each point deform independently of its adjacent points. This local unloading represents an initial strain, and can be described by a tangent map. When experimental data is at hand in a specific situation, the initial strain field may be identified by stating a nonlinear minimization problem where this data is fitted to its corresponding model response. To illustrate the potential of such a method for identifying initial strain fields, the application to an in vivo pressure-radius measurement for a human aorta is presented. The result shows that the initial strain is inconsistent with the strain obtained with the opening-angle-method. This indicates that the opening-angle-method has a too restrictive residual strain parameterization, in this case.
Olsson
T
T
Division of Mechanics, Department of Mechanical Engineering, Linköpings universitet, SE-581 83 Linköping, Sweden. tobol@ikp.liu.se
Stålhand
J
J
Klarbring
A
A
D000465:Algorithms; D001011:Aorta / Q000473:pathology*; D001012:Aorta, Abdominal / Q000033:anatomy & histology* / Q000473:pathology*; D001158:Arteries / Q000033:anatomy & histology / Q000473:pathology*; D001696:Biomechanical Phenomena / Q000379:methods; D003198:Computer Simulation; D004548:Elasticity; D005260:Female; D006801:Humans; D008953:Models, Anatomic; D008954:Models, Biological; D008955:Models, Cardiovascular; D015233:Models, Statistical; D008962:Models, Theoretical; D009141:Musculoskeletal System; D011312:Pressure; D013314:Stress, Mechanical