@unpublished{upm1241, year = {2008}, school = {Caminos}, author = {Claudio Mois{\'e}s Garc{\'i}a Herrera}, title = {Comportamiento mec{\'a}nico de la aorta ascendente : caracterizaci{\'o}n experimental y simulaci{\'o}n num{\'e}rica}, month = {July}, abstract = {Resumen En este trabajo se realiza una caracterizaci{\'o}n experimental y num{\'e}rica del comportamiento mec{\'a}nico de la pared de la aorta humana. Se destaca la importancia de este tema debido al creciente inter{\'e}s en conocer las propiedades y la respuesta mec{\'a}nica de los vasos sangu{\'i}neos por su aplicaci{\'o}n en el tratamiento y diagn{\'o}stico de las enfermedades cardiovasculares. En el presente trabajo se introducen algunos aspectos de los tejidos arteriales y caracter{\'i}sticas generales de las patolog{\'i}as m{\'a}s frecuentes en la aorta. Adem{\'a}s se incluye una recopilaci{\'o}n breve del estado del arte sobre el comportamiento mec{\'a}nico de estos vasos. Tambi{\'e}n se describen los modelos constitutivos de comportamiento no lineal (con grandes deformaciones) e hiperel{\'a}sticos utilizados para la simulaci{\'o}n num{\'e}rica de la pared arterial, en una formulaci{\'o}n implementable en un programa de elementos finitos. Se han realizado una serie de experimentos para caracterizar la respuesta mec{\'a}nica de vasos arteriales. Se llevaron a cabo ensayos de tracci{\'o}n, presurizaci{\'o}n, medici{\'o}n del {\'a}ngulo de apertura e histolog{\'i}a en paredes de aorta con diferentes antecedentes cl{\'i}nicos. Mediante los ensayos se ajustaron los par{\'a}metros de los modelos constitutivos y se obtuvieron otros par{\'a}metros mec{\'a}nicos de inter{\'e}s, como las tensiones y deformaciones de rotura. Con ellos se ha cuantificado el efecto de la patolog{\'i}a y la edad en la respuesta mec{\'a}nica de este tipo de tejidos. Empleando los modelos ajustados en los ensayos de tracci{\'o}n uniaxial se ha realizado la simulaci{\'o}n de diversos ensayos de presurizaci{\'o}n, valid{\'a}ndose con las mediciones efectuadas en este mismo trabajo. Finalmente, tambi{\'e}n se ha llevado a cabo el an{\'a}lisis num{\'e}rico de un cayado a{\'o}rtico en condiciones de funcionamiento fisiol{\'o}gico normales, de hipertensi{\'o}n o en condiciones m{\'a}s severas provocadas por un trauma o accidente. VII Abstract This thesis shows an experimental and numerical characterization of the mechanical behaviour of the human aortic wall. This subject is of paramount importance due to the increasing interest in the mechanical properties and response of blood vessels, in order to improve the treatment and diagnose of cardiovascular diseases. In the present work, some aspects of arterial tissues are presented and the general characteristics of the aorta?s most common pathologies are discussed. In addition, a brief summary of the state of the art on the mechanical behaviour of these vessels is included. A series of experiments have been done in order to characterize the mechanical response of the blood vessels. Four different types of experiments were performed on samples of human aorta with different clinical histories: uniaxial tensile tests, pressurization tests, measurement of the opening angle and histology. The parameters of some constitutive models were obtained adjusting their response to the experimental data from the uniaxial tests. Other mechanical parameters such as strength and deformation at rupture were also obtained. In order to simulate numerically the arterial wall response, two constitutive models with nonlinear (with large deformations) and hyperelastic behaviour, in the context of the continuum mechanics, are described. These formulations have been implemented in a finite element code. Pressurization tests have been simulated using the constitutive models previously tunned with the uniaxial tensile tests. The accuracy of these simulations was checked with the experimental data obtained in this thesis. Finally, numerical analyses of the mechanical response of an aortic arch in different situations were carried out: in normal physiological conditions, with hypertension and in more severe conditions caused by a trauma or an accident. }, keywords = {BIOMECANICA; BIOFISICA; CIENCIAS DE LA VIDA;}, url = {https://oa.upm.es/1241/} }