The Italian Guidelines on Risk Classification and Management of Bridges: Applications and Remarks on Large Scale Risk Assessments

Bridges are essential for guaranteeing the functioning of transportation systems since their failure can cause serious threats to the safety, well-being and economy of modern communities, especially in emergency conditions. Following recent bridge failures, among which include the Morandi bridge in 2018, specific guidelines on risk classification and management, safety assessment and monitoring of existing bridges have been issued in Italy by the Minister of Infrastructure as a mandatory code. They pay particular attention to the evaluation of the residual life span of critical transportation infrastructure dating back to the 1950s and 1960s of the last century. Being a newly issued tool, the Guidelines need to be applied and tested in order to find possible drawbacks and to point out the main factors influencing their results. Therefore, in this study, after a short description of the Italian Guidelines, pointing out some differences with other approaches adopted worldwide, some advantages and disadvantages are discussed by an application to a bridge stock located in the Basilicata region (Italy). Data needed to apply the Guidelines are gathered by a purposely set up procedure that exploits existing databases on road infrastructure (OpenStreetMap) complemented by additional data retrieved by means of public image repositories (Google Street View). By accounting for the qualitative nature of the risk classification results obtained by applying the lower analysis levels of the Guidelines, a prioritization method is proposed for ranking bridges for higher assessment levels and possible interventions, as well as consequent funds allocation. The application shows that the Guidelines' approach tends to provide conservative results. In fact, even in case of bridges with low degradation levels, the final risk classification induces actions undertaken for preliminary or detailed assessment; thus, normal operation (with periodic inspections) would not be possible anymore

Voids and the large-scale structure of the Universe

The Cosmic Web describes the distribution of matter on the largest scales of the Universe. It is composed of dense regions full of galaxies, long filamentary structures and low density voids. In this thesis we introduce the Cosmic Web and we focus on the description of voids, large underdense regions pratically devoid of galaxies occupying the major volume of the Universe. Voids are a key component of the Cosmic Web, since their pristine environment is an important testing ground for our understanding of the importance of environmental influences on the evolution of galaxies. Then we introduce Voronoi and Delaunay tessellations, two random tessellation methods. Tessellation methods are used to divide a d-dimensional space into polytopes covering the whole space without overlapping. Voronoi and Delaunay tessellations are the basis of the DTFE method, useful when we want to compute a continuous field from a large point sample. Finally, we briefly discuss and compare two void finders: ZOBOV and WVF, whose aim is to find density depressions in a set of points, without introducing any free parameters

Lensing voids with peak statistics in massive neutrino cosmologies

Cosmic voids are under-dense regions of the Mpc scale Universe and fundamental components of the Cosmic Web, that describes the spatial distribution of matter on large-scales. In this work we present for the first time in literature the analysis of cosmic voids obtained combining the set of DEMNUni cosmological simulations and the lensing maps obtained via direct ray-tracing across their dark matter distribution, with a 2D tunnel void finding algorithm that identifies voids in lensing convergence maps. We use the peak statistics for the identification of lensing voids: peaks of the convergence field trace voids in this work. We analyze the properties of cosmic voids from lensing convergence maps in two cosmologies: the first one with massless neutrinos and the second one with massive neutrinos (the sum of the masses of the three active species is fixed a Mnu=0.16 eV). We study the properties of lensing voids in these two cosmologies for three probes: CMB-lensing, weak lensing with sources located at z=2, and weak lensing with Euclid photometric redshift distribution of the sources. Furthermore we analyse their evolution with redshift, considering partial CMB-lensing maps in different redshift ranges

Durability of Gerber Saddles in RC Bridges: Analyses and Applications (Musmeci Bridge, Italy)

Guaranteeing adequate safety levels in critical infrastructures such as bridges is essential to modern societies and their vital services. Bridges with reinforced concrete structures are subject to deterioration, especially due to corrosion effects. Gerber saddles are among the key components of bridges which are especially exposed to environmental actions due to their position and reduced possibility of inspection. In this paper, a framework for the durability analysis of these components is proposed, considering the simultaneous presence of permanent loads and environmental actions under the form of chloride ions. Nonlinear numerical simulations adopting the finite element code ATENA are performed, accounting for chloride ingress analyses. The presence of cracks (due to applied loads and/or design/construction defects) which may speed-up corrosion propagation, steel reinforcement loss, cracking and spalling, and their effects on the load-bearing capacity is considered. This framework has been applied to the Gerber saddles of a prominent reinforced concrete (RC) bridge, namely the Musmeci bridge in Potenza, Italy. Durability analyses made it possible to evaluate the saddles’ strength capacity (i) at the time of construction, (ii) after forty-five years since the construction, and (iii) at an extended time of fifty years. The results show that corrosion can influence both the ultimate load capacity and the collapse mechanism

Durability of Gerber Saddles in RC Bridges: Analyses and Applications (Musmeci Bridge, Italy)

Guaranteeing adequate safety levels in critical infrastructures such as bridges is essential to modern societies and their vital services. Bridges with reinforced concrete structures are subject to deterioration, especially due to corrosion effects. Gerber saddles are among the key components of bridges which are especially exposed to environmental actions due to their position and reduced possibility of inspection. In this paper, a framework for the durability analysis of these components is proposed, considering the simultaneous presence of permanent loads and environmental actions under the form of chloride ions. Nonlinear numerical simulations adopting the finite element code ATENA are performed, accounting for chloride ingress analyses. The presence of cracks (due to applied loads and/or design/construction defects) which may speed-up corrosion propagation, steel reinforcement loss, cracking and spalling, and their effects on the load-bearing capacity is considered. This framework has been applied to the Gerber saddles of a prominent reinforced concrete (RC) bridge, namely the Musmeci bridge in Potenza, Italy. Durability analyses made it possible to evaluate the saddles’ strength capacity (i) at the time of construction, (ii) after forty-five years since the construction, and (iii) at an extended time of fifty years. The results show that corrosion can influence both the ultimate load capacity and the collapse mechanism

Human Papillomaviruses and cervico vaginal co-infections in a population of Molise

http://api.altmetric.com/v1/ High grade HPV infections and persistence are the strongest risk factors for cervical cancer.Nevertheless other genital microrganism may be involved in the progression of HPV associated lesions. Bacterial vaginosis (BV), an alteration of vaginal flora involving a decrease in Lattobacilli and predominance of anaerobic bacteria, is the most common cause of vaginal complaints for women of childbearing age. Although the specific role of anaerobic bacteria in the pathogenesis of cervical cancer has not been fully elucidated, it has been suggested that HPV infection alone may not be sufficient for full induction of cervical carcinogenesis, and that the simultaneous presence of cervico vaginal bacteria may increase the risk of neoplastic progression. In this cross-sectional study on 356 enrolled outpatients, statistical analyses revealed a significant association of HPV with Ureaplasma urealyticum detection.Although BV was mildly associated with HPV (OR=2.4), it was more common among the HPV positive women. These data confirm that screening for genital infections may be important to reveal the simultaneous presence of different sexually transmitted microrganisms. These results suggest and emphasize the value of the screening for genital infections in HPV positive patients in order to decrease the presence of the other microrganisms and to reduce the probable synergistic effects of coinfections. Prevention is important not only to avoid other sexually transmitted disease and their sequelae, but also to reduce the influence of concomitant microrganisms on HPV infection. </div