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El proceso de corrosión de armaduras ubicadas dentro del hormigón da origen a la aparición de fisuras lo que reduce la capacidad portante y aumenta las deformaciones de los elementos afectados. Esto tiene directa relación con los estados límites últimos y de servicio, afectando la durabilidad de las estructuras.Diversas variables influyen sobre dicho proceso corrosivo y sobre la generación y propagación de fisuras longitudinales en la superficie del elemento. Existen numerosos estudios experimentales y numéricos que abordan el tema, efectuando el seguimiento de dichas fisuras.El objetivo de este trabajo es estudiar la influencia de la relación adimensional recubrimiento de hormigón / diámetro de barra (C/D) en función de la posición de la barra, y estimar la presión necesaria para generar la fisura. Al efecto se emplea el Método de los Elementos Finitos utilizando un modelo elástico lineal, para simular el proceso de fisuración del recubrimiento en elementos de hormigón armado. La acción sobre el hormigón, provocada por los productos de corrosión, se materializa mediante una presión actuando radialmente sobre el hormigón adyacente a la barra. Se considera que las zonas en que la tensión alcanza la resistencia característica de tracción del hormigón permiten establecer la ubicación de las fisuras y la presión que las origina. Esta última se ha podido relacionar con la pérdida de radio determinada empíricamente por otros autores basados en resultados experimentales, permitiendo llegar a una expresión para estimar dicha presión en función de la relación C/D y de la calidad del hormigón. In this work the mechanical behavior of the

A plan of action was established following certain given guidelines:-The replica should have the same geometrical dimensions as the original rock. -It should be fi xed in the same position as the original rock. -It should be situated at the same place on Cerro La Movediza. -It should consist of a steel structure and it should be coated with a composite material capable of reproducing the colour and texture of the original rock. Activities Topographic StudiesThe planialtimetric topographic surveys determined the position and location of the replica. The geometry of the replica was determined from an analysis of the available information and from the survey of the geometry of the fallen rock that lies at the foot of the Cerro La Movediza. Infrared rays, laser electronic tachometres and GPS receiver systems were used to this end. 1523 points among the three exist-ing pieces of rock were surveyed in a planialtimetric way. The study showed that the rock had an approximate volume of 91 m 3 , an approximate weight of 248 tons and an external surface of approximately 133 m 2 . Geological and Geotechnical SurveysThese studies included, on one hand, the evaluation of the hill discontinuities existing in the location. It was observed that the hill had a fissure, the geological and geotechnical characteristics of which were studied, leading to the conclusion that this did not, in any way, render the task of anchoring the replica to the hill impossible.On the other hand, the characteristics of the rock base, which determined the depth of anchors and their size, were studied. It was reported that the solid rock on the hill had a granite structure and that it presented very good geological characteristics 2 ideal for anchoring the replica. Wind Tunnel StudyThis study allowed the assessment of the impact of the topography on the location and the geometry of the structure in the distribution of the wind pressure. The static and dynamic forces at the anchoring for each direction of the wind were also measured. The range of standard frequencies where higher levels of non-stationary aerodynamic load can be found was also determined.