Analysis of the Behavior of the Piled Foundations of a Group of Earthquake Damaged Buildings

The Sicilian earthquake of 13th December, 1990 was not very strong, but it caused considerable damages on structures, included a group of reinforced concrete buildings located in Augusta town on the east coast of Sicily (Italy). To evaluate the possibility to repair these buildings, an investigation on soil, structures and foundations was carried out. As some buildings were founded on piles, load tests on piles of the piled foundations were carried out. The site was well investigated by means of laboratory and in-situ tests including: standard penetration tests, cone penetration tests, dilatometer tests and seismic tests. To evaluate dynamic stress-strain geotechnical characteristics of soils resonant column tests were also performed. In the paper the experimental results of the load tests are analyzed with the aim to study the behavior of the piles subject to additional seismic loads. Load tests showed that the seismic actions have not damaged the effectiveness of the soil-pile system, as the bearing capacity of the piles appeared unchanged in spite of the additional loads applied on the structures during the earthquake. Nevertheless because the existing piled foundations were enable to carry on the additional horizontal seismic forces, a few number of piles were added

Experimental and Numerical Analysis of the Behaviour of an Embankment Stabilized with Vertical Drains

The paper deals with the settlement analysis of an embankment founded on soft soil and realized for the construction of a reinforced concrete building in the industrial area of Catania (Sicily, Italy). The solution adopted consisted in the construction of the embankment by stages with thirty-three vertical prefabricated drains disposed under the embankment. Soil consolidation settlements took place since the beginning of the embankment construction. The experimental measurements were carried out since August 2000 up to January 2001. The site was well investigated by means of in-situ and laboratory tests. A significantly correspondence between the values of the geotechnical parameters derived from laboratory and in situ tests was observed. Consolidation was investigated and a comparison between computed results and field measurement is presented. The future performance of the embankment is predicted and the end of consolidation has been estimated in terms of settlements, which must be considered of major interest for the evaluation of the stability of the overlying structure

Are We What We Eat? Impact of Diet on the Gut-Brain Axis in Parkinson's Disease

Parkinson’s disease is characterized by motor and non-motor symptoms, such as defects in the gut function, which may occur before the motor symptoms. To date, there are therapies that can improve these symptoms, but there is no cure to avoid the development or exacerbation of this disorder. Dysbiosis of gut microbiota could have a crucial role in the gut–brain axis, which is a bidirectional communication between the central nervous system and the enteric nervous system. Diet can affect the microbiota composition, impacting gut–brain axis functionality. Gut microbiome restoration through probiotics, prebiotics, synbiotics or other dietary means could have the potential to slow PD progression. In this review, we will discuss the influence of diet on the bidirectional communication between gut and brain, thus supporting the hypothesis that this disorder could begin in the gut. We also focus on how food-based therapies might then have an influence on PD and could ameliorate non-motor as well as motor symptoms

A Simplified Approach for the Evaluation of Kinematic Pile Bending

There are two sources of loading of the pile by the earthquake: “inertial” loading of the pile head caused by the lateral forces imposed on the superstructure, and “kinematic” loading along the length of the pile caused by the lateral soil movements developed during the earthquake. Seismic codes prescribe that piles have to be designed for soil deformations arising from the passage of seismic waves which impose curvatures and thereby lateral strains on the piles along their whole length. Accepting these lines, the new Italian seismic normative (NTC, 2008) specify that kinematic effects should be taken into account in the design of pile foundations. Pseudo-static approaches for the seismic analysis of pile foundations are attractive for practicing engineers because they are simple when compared to difficult and more complex dynamic analyses. Thus, in the paper a simplified numerical model for the analysis of the behavior of a single pile subjected to static loadings and/or to lateral soil movements based on the “p-y” subgrade reaction method has been adopted. The approach involves two main steps: first a free-field site response analysis is carried out to obtain the soil displacements along the pile; next a static load analysis is carried out for the pile subjected to the maximum free-field soil displacements at each node along its length and the static loading at the pile head based on the maximum ground surface acceleration

Soil Liquefaction and Risk Analysis From in Situ Tests for the City of Trapani (Italy)

The paper deals with a microzoning criterion based on CPT data to define liquefaction risk of the city of Trapani, Sicily (Italy). Zonation for liquefaction is a fundamental issue to prevent from seismic disasters since, as lessons of past earthquakes teach, liquefaction of sandy soils has been a major cause of damage to buildings. For the evaluation of the seismic risk of the municipal area of Trapani it has been chosen a scenario earthquake which may represent a possible repetition of the 1968 event. For this earthquake a Richter magnitude M= 6.0 and a maximum ground acceleration amax-= 0.30g have been estimated. While new tools and refinements continue to be developed on the subjects of pore pressure build-up due to earthquake shaking and of liquefaction triggering, reliable evaluation methods already exist for liquefaction microzonation purposes. This study focuses on the application of a method for the evaluation of the liquefaction potential to several sites of the city of Trapani, by means of relationships between liquefaction resistance and corrected cone penetration tests (CPT) resistance

A contribution to the phylogeography of Pinctada imbricata radiata (Leach, 1814) (Bivalvia: Pteriidae) from the Eastern Mediterranean Sea by means of the mitochondrial COI marker

Pinctada imbricata radiata (Leach, 1814) was the first Lessepsian bivalve reported in the Mediterranean Sea where it is progressively expanding westward. Its native range includes the Indian Ocean and western Atlantic. The present study provides the first insight into the species’ phylogeographic structure, by analysing sequences of a 385-bp region of the mitochondrial gene coding for the subunit I of the cytochrome c oxydase (COI). Sixty-four individuals collected at seven Mediterranean localities were sequenced; in addition, eight COI sequences of individuals from the species’ native range (Persian Gulf) were retrieved from GenBank. Overall, we detected 10 haplotypes. Samples from both the native range and invaded localities were characterised by low levels of haplotype and nucleotide diversity (total h = 0.351, total π = 0.0013). Significant genetic divergence was found between Persian Gulf and Mediterranean Sea samples, whereas very shallow genetic structuring was observed within the Mediterranean study area. Moreover, no pattern of isolation by distance was detected in the Mediterranean. From a historical demography perspective, our results on Mediterranean samples were consistent with a very recent, or even ongoing, demographic expansion. Range expansion of exotic thermophilic species in this area is a widely observed phenomenon that many authors have related to global warming

La Rete Ecologica Toscana: aspetti metodologici e applicativi

Interventions that can reduce the loss and the fragmentation of ecosystems are very important in the sphere of biodiversity conservation policies applied to areas of high human activity. Ecological networks, on a di erent scale, are important analytical and design tools, and they can highlight sources of biodiversity with the intention of ecological unification. The Tuscany Ecological Network project, based on habitat sustainability models and converted into a planning tool for the landscape plan of Tuscany, has underlined the need to pursue the objectives of biodiversity conservation within a landscape or extended area. The project approaches across the board sectoral policies in urban planning and infrastructure in the agricultural, forestry, and protected areas