A reappraisal of seismic Q evaluated at Mt. Etna volcano. Receipt for the application to risk analysis     

Edoardo Del Pezzo  Francesca Bianco  Elisabetta Giampiccolo  Giuseppina Tusa  Tiziana Tuvé 《Journal of Seismology》2015,19(1):105-119

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Application of an in-plane/out-of-plane interaction model for URM infill walls to dynamic seismic analysis of RC frame buildings     

Francesco Longo  Lydell Wiebe  Francesca da Porto  Claudio Modena 《Bulletin of Earthquake Engineering》2018,16(12):6163-6190

Experimental tests have shown that unreinforced masonry (URM) infill walls are affected by simultaneous loading in their in-plane and out-of-plane directions, but there have been few attempts to represent this interaction in nonlinear time history analysis of reinforced concrete (RC) buildings with URM infill walls. In this paper, a recently proposed macro-model that accounts for this interaction is applied to the seismic analysis of RC framed structures with URM infill walls representative of Mediterranean building stock and practices. Two RC framed structures that are representative of low and mid-rise residential buildings are analysed with a suite of a bidirectional ground motions, scaled to three different intensities. During the analyses, the in-plane/out-of-plane interaction is monitored, showing that cracking of the infills occurs predominantly by in-plane actions, while failure occurs due to a combination of in-plane and out-of-plane displacements, with the out-of-plane component usually playing the dominant role. Along the frame height, the bottom storeys are generally the most damaged, especially where thin infill walls are used. These results are consistent with observations of damage to URM infill walls in similar buildings during recent earthquakes.  相似文献   

Geochemical and Sr-Nd isotopic evidence for petrogenesis and geodynamic setting of Lower-Middle Triassic volcanogenic rocks from central Greece: Implications for the Neotethyan Pindos ocean     

Castorina  Francesca  Magganas  Andreas  Masi  Umberto  Kyriakopoulos  Konstantinos 《Mineralogy and Petrology》2020,114(1):39-56

Mineralogy and Petrology - Geochemistry and Sr-Nd isotopes were determined in Triassic calcalkaline metalava and metapyroclastic rocks from Attica and Argolida, central Greece, to ascertain their...  相似文献   

Mineral chemistry,petrogenesis and evolution of the Ghorveh-Seranjic skarn,Northern Sanandaj Sirjan Zone,Iran     

Alaminia  Zohreh  Mehrabi  Behzad  Razavi  Seyed Mohammad Hossein  Tecce  Francesca 《Mineralogy and Petrology》2020,114(1):15-38

Mineralogy and Petrology - The Ghorveh-Seranjic (GS) skarn is located in the northern part of the Sanandaj-Sirjan zone, NW Iran, which is part of Alpine-Himalaya orogenic belt. The GS metamorphic...  相似文献   

Northwest Africa 6232: Visible–near infrared reflectance spectra variability of an olivine diogenite     

Cristian Carli  Giovanni Pratesi  Vanni Moggi-Cecchi  Francesca Zambon  Fabrizio Capaccioni  Simone Santoro 《Meteoritics & planetary science》2018,53(10):2228-2242

Visible and near-infrared (VNIR) reflectance is an important spectroscopic technique to identify minerals, and their associations, on planetary body surfaces. Howardites, eucrites, and diogenites (HED) are a class of igneous-like meteorites whose genetic connection with asteroid 4 Vesta has since long been inferred and recently confirmed by Dawn mission results. Pyroxene and olivine are the two major mafic minerals present in HED which can be identified with VNIR reflectance measurements. Thus, studying the compositional variability of those phases and their mixtures by means of laboratory spectroscopic measurements on different diogenitic or eucritic samples is one of the prime methods to better understand the evolution of 4 Vesta's crust. Here, we report the VNIR reflectance spectral analysis of a harzburgitic olivine diogenite, Northwest Africa 6232 (probably paired with Northwest Africa 5480), containing variable amounts of olivine as small grains or aggregates. We found that the olivine diogenite spectral parameters (e.g., band position) of powdered samples and polished slabs are in agreement. Moreover, the olivine diogenite band position shifts from synthetic orthopyroxene in accordance with the presence of olivine and chromite. In particular, the presence of a large olivine clast permits us to determine a linear variation of the band position from synthetic orthopyroxene and olivine, but underestimates the presence of olivine in the olivine diogenite spot.  相似文献   

Intraspecific diet shift in Talitrus saltator inhabiting exposed sandy beaches     

Celia Olabarria  Mónica Incera  Josefina Garrido  Iván F. Rodil  Francesca Rossi 《Estuarine, Coastal and Shelf Science》2009

Talitrid amphipods are the most abundant herbivores on exposed sandy beaches. Despite their important role as trophic intermediates between macrophytes and higher levels (i.e. insect and bird) of beach food webs, very little information is available on their feeding patterns. The main aim of this study was to investigate intraspecific differences in the feeding behaviour of Talitrus saltator. We tested the hypotheses that: (1) adult females and males showed different isotope signatures and therefore relied on different sources of food; and (2) patterns of variation of isotope signatures of juveniles differed from those of adult specimens, evidencing a diet shift during the development. We used stable isotope signatures and tested for differences upon the level on the shore, times of the year and beaches experiencing similar morpho-dynamic and environmental conditions. Finally, we investigated the trophic significance of macrophyte detritus in the diet of males, females and juveniles. Results showed that adult males had a more variable diet than females and juveniles (inferred from δ¹³C and δ¹⁵N values). Dual-isotope graphs suggested that Sargassum muticum and Cystoseira baccata wrack could be among the main food sources for both juvenile and adult stage.  相似文献   

Geochemistry of trace elements in surface waters of the Arno River Basin,northern Tuscany,Italy     

Gianni Cortecci  Tiziano Boschetti  Enrico Dinelli  Rosa Cidu  Francesca Podda  Marco Doveri 《Applied Geochemistry》2009

Trace element geochemistry of the Arno River and its main tributaries was investigated on the basis of two sampling campaigns carried out in November 1996 and June 1997. By analyzing filtered and unfiltered water samples, Fe and Al are found in solution mainly as colloidal particles of size lower than 0.45 μm. In June (lower flow rate), Fe and Al are enriched in the filtered waters from the main river, and this feature was interpreted in terms of higher water temperature promoting the formation of smaller particles, thus reducing their aggregation properties. Iron and Al show perfectly synchronous downstream profiles along the Arno River, correlate quite well each to other, and display abrupt concentration increases near to Florence, where the lithology of the catchment changes from siliciclastic dominated to clay-sand (lacustrine-marine)-dominated. The same behaviour is shown by most of the other trace elements in the river, thus supporting a general lithological control. Trace elements in the final part of the Arno River are influenced by flocculation processes in addition to mixing. Adsorption phenomena on oxy-hydroxides are denoted by good elemental correlations with Fe (and Al). Sporadic anomalous concentration values, possibly related to anthropogenic contributions, may prevent such correlations. Referring to the quality of waters for potable use and fish life, toxic elements are below the acceptable limits of current European regulations, with few exceptions for Hg exceeding guideline values. Multivariate analysis groups trace elements according to geochemical affinities and natural or anthropogenic sources, thus distinguishing contaminated from uncontaminated samples. The results achieved in this work will help regional and national Authorities for compliance with the EU water policy, especially in assessing the water quality at the river basin scale and its vulnerability to human activities.  相似文献   

3D GIS Supporting Underground Urbanisation in the City of Turin (Italy)   总被引：1，自引：1，他引：0  

Francesca de Rienzo  Pierpaolo Oreste  Sebastiano Pelizza 《Geotechnical and Geological Engineering》2009,27(4):539-547

This paper introduces a 3D geological and geotechnical model of the subsoil of the city of Turin managed by means of a Geographical Information System (GIS). The 3D GIS of the subsoil of Turin represents a useful decision-support tool in the underground management for engineering purposes and it’s here proposed as base geological elaborate to support future underground work in the city. In the final part of the paper, an application of the information coming from the 3D model is shown to define the characteristics of the optimal excavation machines (the type and disposition of tools on the head and the necessary engine power) for the future developments of the Underground Metro System.  相似文献   

The 1511 Eastern Alps earthquakes: a critical update and comparison of existing macroseismic datasets     

Romano Camassi  Carlos Hector Caracciolo  Viviana Castelli  Dario Slejko 《Journal of Seismology》2011,15(2):191-213

Three earthquakes condition the seismic hazard estimates of the Eastern Alps: the 1348 “Villach”, the 1511 “Idrija”, and the 1976 Gemona events. Only the last one can be well documented, while doubts remain for location and size of the other two. New documents have been found about the 1511 quake that, together with a complete revision of the information already available, offer some new indications on the location and size of the event.  相似文献   

Identification of accelerometric stations in ITACA with distinctive features in their seismic response     

Dino Bindi  Lucia Luzi  Francesca Pacor  Roberto Paolucci 《Bulletin of Earthquake Engineering》2011,9(6):1921-1939

In this work, we analyze the records of the Italian strong motion database (ITACA, ) with the aim of identifying stations affected by site effects that are not captured by standard seismic classification schemes. In particular, we consider four different site classifications, two of them based on geological/geophysical characteristics and two driven by data. For each classification we develop a ground motion prediction equation using a random effect approach to isolate the between-station and within-station distribution of errors. The site coefficients obtained for the different classes confirm that site amplification effects are significant for both the horizontal and vertical components. The between-station error normalized to the standard deviation of the between-station error distribution is then used to identify stations characterized by large errors, attributable to site effects not accounted for by the classification schemes. The results show that large errors can affect the predictions when the site effects are not uniquely related to the reduction of the seismic impedance in the uppermost layers. For example, amplifications of ground motion over the long period range are observed for stations installed within alluvial closed-shape basins, as consequence of locally generated surface waves. For these stations, classifications based on the horizontal to vertical response spectra ratio are not reliable, since amplifications are also affecting the vertical component. Another interesting feature which emerges from the analysis is the significant de-amplification of short period spectral ordinates that seems to be related to stations typically set in at the foundation level of massive structures. To increase the usefulness of the data set, the most important distinctive features of the strong motion stations are documented in the ITACA database reports containing the instrument information and the available geological-geotechnical data.  相似文献