Beam-column joints can play a key role on the seismic behavior of reinforced concrete buildings. Until now studies and experimental investigations on this topic have been mainly focused on beam-column joints with stiff beams, i.e. beams with height larger than the thickness of the adjacent floor slab. However, especially in the European residential building stock, frame structures are often equipped with wide - therefore rather flexible - beams. However, not many studies have been devoted so far to this type of connection, therefore an experimental investigation on full scale beam-column joints with wide beam was planned at the University of Basilicata and is currently in progress. In the present paper the main results of two cyclic tests are reported and discussed specifically analyzing the role of the axial load applied to the column on the joint performances and damage mechanisms. Test results highlights that the axial load value has a significant influence of on deformation capacity and ductility behavior.

The growing number of demand for a widespread of health monitoring for strategic buildings in seismic areas has emphasized the need to realize in-depth scientific studies, in order to verify the feasibility of economic and fast methods to detect anomalous vibrations, to execute post earthquake warning and monitoring, damage assessment and first damage scenarios. Generally, an effective system for structural health monitoring requires an appropriate number of sensors, suitably located in the structures, and complex elaborations of big amounts of data. The simplified method presented in this paper is based on a statistical approach that uses the most significant data recorded on the top floor of the building, with the purpose of extracting information on the maximum inter-story drift, used as damage indicator. The parameters considered in the method are (i) maximum top acceleration, (ii) the first modal frequency variations and (iii) the equivalent structural viscous damping variation. A big amount of experimental data relevant to several tests carried out on scaled R/C models and numerical non linear dynamic analyses have been used to verify the feasibility of this approach.

Abstract. This paper reports on the results of an ongoing Research Project aimed at computing the risk of collapse of new buildings conforming to the

Beam-column joints play a key role on the seismic behavior of reinforced concrete buildings. Many of these buildings, although they belong to earthquake prone countries, were designed only to withstand gravity loads, thus without appropriate strength and ductility capacity with respect to seismic actions. Beam-column joints with flat or wide beam are rather widespread in the European residential building stock. Contrarily to joints provided with stiff beams, there are a few studies devoted to evaluate their performance and, especially, the arrangement and effectiveness of strengthening solutions for this type of joints. For this reason an experimental program has been setup in order to evaluate the effectiveness of simple and easy to apply strengthening techniques derived from the CAM technique. Three identical specimens were tested, one in the as-built condition and two specimens after the application of steel based strengthening solutions. The present paper shows a preliminary analysis of the test results highlighting the effectiveness of the techniques proposed in improving the seismic behavior of the specimens under study

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In this article, the dynamic behavior of a base isolated structure located in Augusta City (Italy) is analyzed during ambient noise and during several release tests. On the 22th of May 2013, through different release tests, several accelerometers have been installed within the structure and on the surrounding soil in order to acquire the dynamic response of the structure and the effects of soil-structure interaction. During the experimental campaign, the dynamic behavior of the structure has been monitored before, during and after each test, comparing the dynamic characteristics in the different phases and evaluating possible damages on nonstructural elements. Particularly, the base-isolated structure has been characterized in terms of eigenfrequencies, equivalent viscous damping factor and mode shapes in ambient noise (considering the superstructure as a fixed-base structure) and during the release tests (monitoring the dynamic behavior of superstructure, base isolation system and underground floor). The aim of this article is to analyze the experimental behavior of the based isolated building and evaluate soil-structure effects in terms of energy released into the ground and maximum acceleration produced on the surrounding structures during the released tests.

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