Modeling and Seismic Response Analysis of Italian Code-Conforming Reinforced Concrete Buildings

ABSTRACT

This study investigates the seismic response of reinforced concrete buildings designed according to the current Italian building code. Number of stories, site hazard, presence and distribution of masonry infill panels, and type of lateral resisting system are the key investigated parameters. The main issues related to design and modeling are discussed. Two Limit States are considered, namely Global Collapse and Usability-Preventing Damage. The main aim of the study is a comparison between the seismic response of the buildings, investigated through nonlinear static and dynamic analyses. Irregularity in the distribution of infill panels and site hazard emerge as the most influential parameters.     

What do divided cities have in common? An international comparison of income segregation

This paper provides a comparative assessment of income segregation in cities of 12 countries. We use spatial entropy indexes based on small‐scale gridded income data and consistent definition of city boundaries to ensure international comparability of our segregation measures. Results show considerable variation in the levels of income segregation across cities, even within countries, reflecting the diversity within urban systems. Larger, more affluent, productive, and more unequal cities tend to be more segregated. Urban form, demographic, and economic factors explain additional variation in segregation levels through the influence of high‐income households, who tend to be the most segregated. The positive association between productivity and segregation is mitigated in polycentric cities.     

WHAT DRIVES THE URBAN WAGE PREMIUM? EVIDENCE ALONG THE WAGE DISTRIBUTION

This paper aims at disentangling the role played by different explanations on the urban wage premium along the wage distribution. We analyze the wage dynamics of migrants from lower to higher density areas in Italy, using quantile regressions and individual data. The results show that unskilled workers benefit more from a wage premium accruing over time, while skilled workers enjoy a wage premium when they migrate as well as a wage increase over time. Further, we find that for unskilled workers the wage growth over time is mainly due to human capital accumulation in line with the “learning” hypothesis, while for skilled workers the wage growth is mainly explained by the “coordination” hypothesis, i.e., cities enhance the probability of better matches between workers and firms.     

Radiocarbon and U-series dating of the endemic deer Praemegaceros cazioti (Depéret) from “Grotta Juntu”, Sardinia

Radiocarbon and U-series methods (²³⁰Th/U and ²³¹Pa/²³⁵U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.     

A study by thermal treatment and X-ray powder diffraction on burnt fragmented bones from tombs II,IV and IX belonging to the hypogeic necropolis of “Sa Figu” near Ittiri,Sassari (Sardinia,Italy)

In the course of an anthropological investigation of three tombs of the hypogeic necropolis of “Sa Figu” (near the village of Ittiri in North Sardinia, Italy), numerous burnt bone fragments were collected. In particular, from the whole necropolis we selected a tenth of long bones from tomb IV, a small fragment of femur from tomb II and four fragments belonging to tomb IX. The aim of this work is to determine a temperature range to which the bone fragments were heated, in order to assess a funerary cremation which was presumably used at that time to quickly and hygienically eliminate the flashy parts of deceased people rather than a purification rite with fires inside the sepulchres. We attempted to evaluate the range of temperature to which the bones were likely subjected, making a joint use of thermal treatment and powder X-ray diffraction investigations. From our X-ray line broadening results carried out with a modern approach (Rietveld method), it emerged that a group of five fragmented burnt bones (one specimen belonging to tomb IV, the other four from tomb IX) were subjected to a heat treatment in a temperature range from 600 and 750 °C. Conversely another group of bones (belonging to tombs II and IV) turned out to be subjected to temperatures not higher than 250 °C.     

Archaeometric evidences of the 4th–2nd century BC amphorae productions in north eastern Sicily

This work focuses on the petro-archaeometric analysis of several transport amphorae dated back from 4th to 2nd century BC which were found in various archaeological excavations recently carried out in Messina and Milazzo (north eastern Sicily). These amphorae, generally known as Graeco-Italic, raise the problem of the identification of their production areas. Petrographic analyses proved the presence of two groups characterised by the presence of coarse metamorphic or volcanic inclusions and one group with finer metamorphic inclusions. Multivariate statistical analyses made it possible to detect the production area of the amphorae with metamorphic inclusion in north eastern Sicily, comparing them with locally produced bricks and clay sediments cropping out near the ancient cities. On the contrary, the studied amphorae rich in volcanic inclusions have petrographic and chemical features which can be attributed to production areas in the Campanian region.     

Experimental Characterization of Ancient Metal Tie-Rods in Historic Masonry Buildings

Metal tie-rods play a decisive role in the control of horizontal thrusts in historic masonry buildings. The main goal of the present study is to investigate the relationship between metallurgical and mechanical properties of original tie-rods in order to contribute to a wider study on ancient building stability and their restoration protocols. This article presents the results of an experimental test campaign carried out on 14 historic tie-rods (dating back from 16^th–19^th century) recovered from restoration works or building demolitions. Stress-strain mechanical tests showed that the elastic modulus of the material is comparable to that of modern structural steel, while the strength and the elongation capability are significantly lower, with a large scatter. Further analyses based on metallography allowed us to assess that this mechanical behavior depends on the heterogeneous nature of the material, which can eventually be compared to a composite with vitreous elongated particles in a ferritic or ferrito-pearlitic matrix. The origin of such metallurgical condition is related to the iron making based on direct smelting from ores.     

Endangered minority and regional languages (‘dialects’) in Italy

The Italian linguistic situation is characterised by a remarkable number of language varieties, although the development of Italian in the past 150 years has been the cause of a language shift from local languages to Italian. The degree of endangerment suffered by so-called ‘Italian dialects’ is shown using the Major Evaluative Factors of Language Vitality drawn up by a UNESCO ad hoc expert group in 2003, and the data offered by the 2006 ISTAT survey on language use. The debate in Italy on the vitality of ‘dialects’ and their future has done little to activate mechanisms and strategies to reverse the worrying language shift that both minority languages and ‘dialects’ are undergoing.