In order to subdivide members into ductility classes is important to know the slenderness factor “
”, which can be defined as the ratio between critical tension that brings local instability of the compressed flange or the flexural-torsional instability and the yield tension. The current paper deals with the redefinition of coefficients in the expression of the over-strength factor “
” proposed by the new seismic Italian code OPCM 3274 for hot rolled and welded double-T sections and with the introduction of a new expression of the same parameter for other members with different shape like rectangular, square and circular hollow sections and slender C sections.
This paper deals with the seismic vulnerability assessment analysis of some existing typified school buildings in Albania. This is particularly important for the estimation of probable damages and buildings’ behaviour in case of strong earthquakes. Three typified of R/C school buildings are selected for evaluation. Conclusions are only referred to the selected buildings. However, the developed approach may be used for the analysis of other structural types.The first step of the study is the identification of the seismic zones — where the buildings are located — and the period of their constructions. Second, information on the seismic design conditions of the buildings is used and pushover analyses are performed in order to provide their respective capacity curves. Subsequently, using the procedures developed in the L2-Method — i.e.: modeling bilinear capacity curves in AD format, defining the damage threshold levels, calculating cumulative probability, and performing regression analysis — the fragility curves are obtained.After considering the different seismic sites reviewing code requirements (the existing Albanian Code KTP-N2-89 and Eurocode 8) and analyzing performance points, the probable damage levels of the buildings is assessed.
Cold formed steel constructions are, among the contemporary systems, one of the most competitive in terms of lightness, high structural performance, short execution times, quality of product and sustainability. This paper aims to summarize some important studies carried out at University of Naples “Federico II”, that investigated the feasibility of using cold formed steel systems in seismic zone and, in particular, characterized the behavior of shear stud walls under horizontal loads. Hence, a contemporary house design is presented to show architectural and environmental possibilities.
The paper presents significant aspects regarding the concept and details of constructive solutions used to design and implement an energy efficient school building in Romania. Although the site is in a moderate seismic zone, the structural needs of the building impose specific insulation solutions for making the passive house concept applicable. Renewable energy sources are also applied to optimize the maintenance cost and to reduce the payback period to a feasible level. In order to prove the benefits of the solutions, to justify the higher initial investment, to improve the real-time energy consumption of the building, as well as to keep track of the internal climate parameters, a complex monitoring system was planned and implemented. Details and correlation between specific details and temperature sensors distribution are also presented.
In the seismic source zone of Bánát more than 600 earthquakes are known since 1773 among them six events with magnitude of 5.0–5.7 measured on the surface magnitude scale. The macroseismic reinterpretation of the April 2, 1901 earthquake yields epicentral intensity of VII on the European Macroseismic Scale, and a focal depth value of 12 km. Based on empirical relations the maximum rupture area is estimated as 50–55 km
and the maximum displacement along the fault is about 16 cm in the Bánát seismic zone due to the
= 5.7 event occurred on July 12, 1991. The average recurrence that we may expect an earthquake of
≥ 3.4 every 1 year, an earthquake of
≥ 4.3 every 10 years and an earthquake of
≥ 5.3 every 100 years in the studied source zone. The probabilistic seismic hazard assessment predicts 1.3–2.1 m/sec
peak ground accelerations, and 6.7–7.3 maximum (theoretical) earthquake intensity values with 10% chance of exceedance for an exposure time of 100 years in the region.
The correlations between seismic activities and tidal periodicities are investigated at three seismic zones: Vrancea (Romania), Bucaramanga (Colombia) and Hindu Kush (Afganistan). The epicenter of earthquake nests distribution is characterized by intermediate-depth. In this paper, we study the influences of the principal lunar and solar semidiurnal tidal components M2 and S2 on seismic activities. The tidal phase is determined by HiCum stacking method according to the earthquake occurrence time and location. The stacking function could be shifted in time and space domain which provides the possibility to evaluate the seismic activities and tidal periodicities at both. The tidal phase distribution was tested by two independent methods Schuster and Permutation. The null hypothesis between seismic activities and selected tidal periodicities is rejected when the statistical
-values obtained by the two tests reach less than 5% level. As a result of the shift stacking function in time axis, a systematic temporal pattern related to the decrease of the
-values seems to be preceding occurrence of the larger earthquakes. A “tidal tomography” map is obtained when stacking function is shifted in 3D geometry following the epicenters distribution.