1,721,046 research outputs found
Incidenza delle norme dettate dal testatore sul contenuto del contratto di divisione
No full textStudio circa l'incidenza delle norme dettate dal testatore per la divisione dei beni ereditari, ai sensi dell'art. 733 c.c., e della loro derogabilita
La condotta di guida colposa: introduzione
No full textIntroduzione dell'argomento relativo alla condotta di guida colposa nella responsabilità civile
Improving the seismic performance of non-structural elements using Building Information Modelling
No full textThe post-earthquake functionality of critical facilities, such as hospitals, relies on the continued
operation of non-structural elements including piping systems, partitions, ceiling systems and other medical
equipment. The damage observed during past earthquakes showed the poor seismic performance of nonstructural
elements and the need to improve their design and installation strategies. The application of
performance-based seismic design to the entire building environment could be the possible solution to
achieve desirable performance objectives for various seismic hazard levels. In this context, the use of
Building Information Modelling is a promising approach to apply the seismic design of non-structural
elements into practice. The data available in Building Information Models could be used to perform
automatically the seismic design of non-structural elements and then to identify the interferences (i.e. clash
detection) between all structural and non-structural elements in the building. In this paper, a conceptual
framework to perform the automatic seismic design of non-structural elements using the information
available in Building Information Models is presented. The effectiveness of the procedure is demonstrated
though a simple application in which the seismic design of pressurized fire suppressant sprinkler piping
systems and of ceiling systems installed in a reinforced concrete building is performed. The bracing elements
required by current seismic provisions for non-structural elements considered are automatically reintroduced
in the original Building Information Model. The automatic updating of the Building Information
Model allowed to perform the clash detection and to verify if the bracing positions needed to be modified
in order to optimize efficiently the seismic design of the entire building environment
Towards a Novel Paradigm in Blind Deconvolution: From Natural to Cartooned Image Statistics
No full textEstimating consistent relative displacement and absolute acceleration floor response spectra in elastic buildings
No full textThe need to properly design non-structural elements to withstand earthquakes has become an
important objective within the earthquake engineering community. In the performance-based seismic design
framework, the achievement of adequate performance objectives, for increasing seismic intensities, is not
only related to the performance of structural members but also to the behaviour of non-structural elements.
Recently, a direct displacement-based design methodology for the seismic design of non-structural elements
was developed. A crucial aspect of this design methodology for non-structural elements is the definition of
the seismic demand as a relative displacement floor response spectrum. This paper presents a simple
procedure for estimating relative displacement floor response spectra for building structures responding in
the elastic range. Relative displacement and absolute acceleration floor response spectra were computed for
a reinforced concrete moment resisting frame via dynamic time history analyses and were compared with
floor response spectra predicted by means of a recent methodology available in the literature. It was
observed that this methodology was able to predict well absolute acceleration floor response spectra but
was inconsistent in its prediction of relative displacement floor response spectra for non-structural periods
longer than the natural period of the supporting structure. Accordingly, a correction procedure to predict
consistent relative displacement and absolute acceleration floor response spectra was implemented. This
new procedure allows predicting the relative displacement floor response spectrum by constraining its
ordinates at very long non-structural periods to the expected peak absolute displacement of the floor. The
resulting acceleration and relative displacement response spectra are then consistently related by the wellknown
pseudo-spectra relationship over the entire non-structural period range
L’INFLUENZA DELLE TAMPONATURE SUL PERIODO ELASTICO DI TELAI ESISTENTI IN C.A.
No full textThe damage observed in past earthquakes, has shown as the presence of infills significantly influences the seismic performance of RC moment resisting frames. The reduction of the elastic period related with the increase of stiffness due to infills causes a different seismic behaviour and in particular a variation in the seismic demand.
In this work the elastic period of infilled RC frames designed only for gravity loads and according to the Italian code available before the introduction of seismic design has been evaluated. A parametric analysis has been carried out, including the influence of the infills mechanical properties. Obtained results allowed to calibrate a relationship able to furnish the first elastic period of the frames taking into account all the parameters investigated. Finally, the comparison between the proposed relationship and that provided by the Italian Code evidences in some cases significant scatters in terms of seismic demand, suggesting the need of further investigations and validations
Floor Acceleration Demand on Steel Moment Resisting Frame Buildings Retrofitted with Linear and Nonlinear Viscous Dampers
No full textAn improvement of the seismic performance of a building can be achieved by adding
supplemental damping through viscous dampers. In some cases, however, the incorporation of viscous
dampers in the structure can cause an increment of the seismic demand on acceleration-sensitive nonstructural
elements. Two steel moment resisting frame buildings of three and six stories were selected from
the SAC Steel Project in California. These buildings were equipped with linear and nonlinear viscous
dampers designed by following a uniform distribution design approach in which a unique damping
coefficient is assigned to all dampers along the building’s height. Additionally, three target first modal
damping ratios were used along with six different velocity coefficients of the fluid viscous dampers.
Nonlinear time-history analysis was carried out with the FEMA P695 far-field ground motion record set.
The records were scaled to two intensity levels and floor acceleration time histories and 5% damped floor
acceleration response spectra were obtained. The results show that the implementation of viscous dampers
generally reduces the seismic demand in terms of floor acceleration compared to the original (nonretrofitted)
building in most cases. Nevertheless, the floor acceleration demand varies significantly when the
damping ratio and the velocity coefficient of fluid viscous dampers are varied. In some cases, the peak floor
accelerations and the floor spectral accelerations in certain non-structural period ranges can exceed that of
the original building
Expected seismic response and annual seismic loss of viscously damped braced steel frames
No full textNon-linear behaviour of masonry infilled RC frames: Influence of masonry mechanical properties
No full textUnreinforced masonry infilled R.C. frames are a widespread structural system worldwide; even if the damages observed during past earthquakes highlight the influence of masonry infills on the seismic per- formance of structures, the common practice considers the infill as nonstructural elements. The infills are made with a large variety of materials and with different construction typologies; nevertheless, a large number of studies have been carried out in the last years to investigate the interaction between the infill panels and the surrounding R.C. frames, few researches have been focused on the influence of mechanical properties of masonry infills on the structural performance. In this study the seismic performance of R.C. frames designed for gravity loads according to the code prescription in force in Italy between 1950s and 1970s has been evaluated. A parametric analysis has been to investigate the influence of the mechanical and geometrical properties of masonry infills on the whole structural response; the seismic behaviour has been analyzed in terms of capacity, ductility and collapse mechanisms. The results showed as the mechanical properties of masonry infills should be adequately evaluated before to proceed to the seismic vulnerability assessment of existing structures because they significantly affect the global behaviour of R.C. frames
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