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dc.contributor.advisorSundaram, Paul A.
dc.contributor.authorHerger, Edward
dc.date.accessioned2018-04-09T15:39:06Z
dc.date.available2018-04-09T15:39:06Z
dc.date.issued2009
dc.identifier.urihttps://hdl.handle.net/20.500.11801/437
dc.description.abstractThe mechanical properties of collagen in the form of Type I fascicles obtained from rat tail tendons were determined under dynamic loading conditions. Experimental procedures and apparatus were developed to establish a relationship between parameters of dynamic loading and the ability of collagen to resist damage. The viscoelastic behavior of the fascicles under sinusoidal tensile loading was haracterized in terms of loss tangent and dynamic modulus and in terms of models developed specifically to explain the observed results. Dynamic analysis showed an average loss tangent of approximately 0.3 at 0.5 hertz, a value which agrees well with literature. Type I collagen fascicles were able to withstand higher amounts of impulse, defined by area under the force-time curve of the loading function, at higher frequencies for the range tested. Detailed strain analysis revealed two distinct behaviors, a linear hysteric progression of strain which dominates at low loading frequencies and a saturating curve behavior which prevails at high loading frequencies. Computational and mechanistic models have been established for each case. The action of an intermolecular chain mechanism caused by the addition of strain energy affecting the state of cross linking in the material is hypothesized to explain the observed phenomena. Support for this hypothesis is based on the definitive results indicating higher order time-mechanical behavior prevalence with increasing loading frequency.en_US
dc.description.abstractLas propiedades de fibras de colágeno Tipo I obtenidas de los tendones de la cola de rata fueron investigadas. Procedimientos experimentales y equipos especiales fueron desarrollados para establecer la relación entre las características de carga dinámica y la resistencia de la fibra contra daño. El comportamiento viscoelastico de las fibras fue definido en terminados de “loss tangent” y “dynamic modulus” y también con modelos desarrollados según los resultados específicos. Análisis dinámico dio 0.3 para “loss tangent” a frecuencia de 0.5 hertzios, un valor que tenga buena correlación con otros valores publicados. Fue observado que fibras de colágeno Tipo I soportan mas impulso cuando cargadas a mayor frecuencia. Un análisis detallado de deformación mostro dos comportamientos de progresión de deformación distintos. Típicamente con variación de carga a bajas frecuencias, la progresión de deformación fue lineal. Por lo tanto, con altas frecuencias, progresión de deformación mostro típicamente un comportamiento curvado. Varios modelos han sido establecidos para caracterizar el comportamiento observado. Una hipótesis esta ofrecido explicando el comportamiento a través de un modelo que se enfoca en el proceso de aumentación de energía de deformación que provoca actividad entre enlaces transversos conectando las cadenas de moléculas.en_US
dc.language.isoenen_US
dc.subjectcollagen fasciclesen_US
dc.subject.lcshCollagen--Mechanical propertiesen_US
dc.subject.lcshDynamic testingen_US
dc.subject.lcshTendons--Mechanical propertiesen_US
dc.titleCharacterization of the dynamic onset of fibric damage in type I collagen fasciclesen_US
dc.typeThesisen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2009 Edward Hergeren_US
dc.contributor.committeeGoyal, Vijay K.
dc.contributor.committeeValentín, Ricky
dc.contributor.representativeSingh, Surinder
thesis.degree.levelM.S.en_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.collegeCollege of Engineeringen_US
dc.contributor.departmentDepartment of Mechanical Engineeringen_US
dc.description.graduationYear2009en_US


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