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Se discute el ejemplo de un caso real en el que, sobre un túnel existente que se instrumenta con fibra óptica, se construye un edificio. Ello permite hacer el seguimiento de la historia de cargas de una estructura desde que se coloca la fibra óptica. Para constatar que no se ve afectado estructuralmente el túnel durante el período de construcción, se instrumentan secciones del mismo y se miden las microdeformaciones que se producen, que se comparan con las del modelo. Se han podido apreciar las ovalizaciones y tensiones en la bóveda durante las distintas fases del proceso constructivo, estando todas ellas por debajo de los valores límites establecidos en el plan de contingencias. Esta técnica ha permitido validar durante todo el proceso las obras realizadas.

The preservation of old downtowns has become a necessity of growing interest. New urban policies have been approved in different countries in order to revive the old city centers and make them economically sustainable. In this global trend, the municipality of Manresa (Barcelona) developed an important urban planning operation in the old district that included the demolition of a group of existing buildings and the construction of a new modern one in close proximity to a group of old residential buildings which are cultural heritage of the city. As a consequence, specific areas of risk were generated which lead to the adoption of precautionary measures to ensure safety. This article presents the preliminary analysis, diagnostics and monitoring carried out on this group of heterogeneous old buildings, as well as the results and precautionary measures taken to ensure their safety. The article also provides a translatable methodology that combines qualitative and quantitative aspects.

The overall performance of a concrete structure is considered to be a key issue when determining its service life. The widespread use of precast concrete and consideration of durability as a design parameter in most of the international codes have the goal of achieving concrete structures with better durability. Nevertheless, the early deterioration of concrete is still common in a large number of concrete structures, which reduces the service life. This paper presents a case study of an existing precast concrete cooling tower for a thermal power station subjected to severe marine exposure conditions, which showed symptoms of serious deterioration after operating for three years. The main goal of this study was to clarify the origin of the accelerated deterioration of the structure. Wetting-drying cycles were identified as the main cause of the early deterioration of the structure. Furthermore, estimations on its remaining service life were made considering the accelerating effect of the wetting-drying cycles. Finally, the variation in the safety factor of the main structural elements was evaluated.

The final publication is available at Springer via http://dx.doi.org/10.1617/s11527-015-0654-y An experimental campaign involving the compressive testing of a brick masonry pillar extracted from a historical building is presented in this paper. The test procedure and the instrumentation are designed in order to determine, in addition to the compressive strength and global Young's modulus of the structure, the behavior in different parts of the pillar. Material samples, representative of the external leaf and the infill, are extracted from the pillar and tested in compression. Differences in strength and elasticity of the two components are critically presented and their influence on the maximum load and failure mode of the pillar are discussed. Finally, a simple analytical model is employed in order to quantify the effect of the mismatch of Young's modulus of the two components of the pillar. Analogies between the studied pillar and three-leaf wall masonry are drawn.