Reinforced concrete bridges deteriorate over time, therefore displaying a regular need for structural assessment and diagnosis. The reasons for their deterioration are often the following: (a) intensive use, (b) very dynamic loads acting for long periods of time, (c) and sometimes chemical processes that damage the concrete or lead to corrosion of the reinforcement. Assuming the hypothesis that both the stiffness of the material and its density change over time, these parameters shall be identified, preferably in a non-destructive way, in different locations of the investigated structure.
View Article and Find Full Text PDFFinite element models of human crystalline capsular bag and zonular fibers are used to estimate the mechanical response of the capsule to the presence of a C-loop Intra-Ocular Lens (IOL) after cataract surgery, to assess the influence of capsulorhexis size, shape and location on IOL decentration and tilt. The model includes, in the anterior capsule, a hole with variable size, shape and position, which represents the rhexis obtained in a manual or laser-assisted manner. The IOL is not explicitly modelled, but its action is reproduced by means of a set of elastic ties, connecting the opposite sides of the bag and exerting the force corresponding to an expanded IOL.
View Article and Find Full Text PDF