24 research outputs found
The new engineering geological map (carta litotecnica) of Tuscany (Italy)
Municipal administrations in Italy must be provided with thematic maps and documentation which describe the geological, geomorphological, lithological, hydrogeological and hydraulic characters useful to manage spatial planning issues. Among these documents, a âLithotechnicalâ (or âLithological-Technicalâ) map is drawn up, generally at the scale of 1:10,000, by organizing the geological formations into lithotechnical units according to their lithological and physical-mechanical properties. Often, this map also integrates the results of previous field and borehole investigations. However, this map is characterized by a certain degree of subjectivity because it is supported by few specific quantitative data. We present a new method for the regional scale engineering geological classification of sub-surface rock and soil masses obtained by integrating the geological map at the scale of 1:10,000 as a reference document, with a large set of data obtained through the collection and processing of new lithological and physical-mechanical observations and measurements of the outcropping geological formations. The adopted procedure involves both the extensive in situ use of the Schmidt's hammer and the execution of laboratory tests, such as the Slake Durability Test (Franklin & Chandra, 1972) and the determination of the rock unit weight. These tools and tests allow us to acquire a large set of quantitative in situ and laboratory data with known repeatability to obtain a regional scale GIS database providing the classification of the lithological and physical-mechanical characteristics of a wide range of geological formations. As a first step, each outcrop is classified according to a new engineering geological nomenclature system described by the code XXv[y]_[Z] whose values are obtained by integrating: i) a lithological parameter XXv evaluated from both typical characters of the geological formations under analysis and outcrop observations; ii) an engineering geological parameter [y] obtained by the results of the Slake Durability Test; iii) an engineering geological parameter [Z] (Rockmass Quality Index - RQI) evaluated at the outcrop scale on the basis of a large set of sclerometric measurements. The results of outcrop classification are stored into a point topology GIS dataset and are then processed and spatialized in order to assign the XXv[y]_[Z] code to the geological formations, thus obtaining the new engineering geological map. Within the framework of research agreements among Regione Toscana administration, the Consorzio LaMMA, the CNRIGG and the Department of Earth, Environmental and Physical Sciences of the University of Siena, the latter being the leader for their implementation, more than 300 geological formations were analysed and classified, and the new engineering geological GIS map was realized in Tuscany for the provinces of Arezzo, Florence, Lucca, Massa-Carrara, Pistoia, Prato and Siena (ca. 15,000 km2)
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
Optimization of the gas flow in a GEM chamber and development of the GEM foil stretcher
The gas electron multiplier technology has been proven to tolerate rat e
larger than 50 MHz/cm2 without noticeable aging and to provide sub resolution
on working chambers up to 45 cm x 45 cm. A new gas electron multiplier-based
tracker is under development for the Hall A upgrade at Jefferson Lab. The
chambers of the tracker have been designed in a modular way: each chamber
consists of 3 adjacent gas electron multiplier modules, with an active area
of 40 cm x 50 cm each. We optimized the gas flow inside the gas electron
multiplier module volume, using the COMSOL physics simulator framework; the
COMSOL-based analysis includes the design of the inlet and outlet pipes and
the maximization of the uniformity of the gas flow. We have defined the
procedures for the assembling of the gas electron multiplier modules and
designed a mechanical system (TENDIGEM) that will be used to stretch the GEM
foils at the proper tension (few kg/cm); the TENDIGEM is based on the
original design developed at LNF
OPTIMIZATION OF THE GAS FLOW IN A GEM CHAMBER AND DEVELOPMENT OF THE GEM FOIL STRETCHER
The Gas Electron Multiplier (GEM) technology has been proven to tolerate rate larger than 50 MHz/cm 2 without noticeable aging and to provide sub millimeter resolution on working chambers up to 45x45 cm
A Machine Learning Approach to Extract Rock Mass Discontinuity Orientation and Spacing, from Laser Scanner Point Clouds
This study wants to give a contribution to the semi-automatic evaluation of rock mass discontinuities, orientation and spacing, as important parameters used in Engineering. In complex and inaccessible study areas, a traditional geological survey is hard to conduct, therefore, remote sensing techniques have proven to be a very useful tool for discontinuity analysis. However, critical expert judgment is necessary to make reliable analyses. For this reason, the open-source Python tool named DCS (Discontinuities Classification and Spacing) was developed to manage point cloud data. The tool is written in Python and is based on semi-supervised clustering. By this approach the users can: (a) estimate the number of discontinuity sets (here referred to as âclustersâ) using the Error Sum of Squares (SSE) method and the K-means algorithm; (b) evaluate step by step the quality of the classification visualizing the stereonet and the scatterplot of dip vs. dip direction from the clustering; (c) supervise the clustering procedure through a manual initialization of centroids; (d) calculate the normal spacing. In contrast to other algorithms available in the literature, the DCS method does not require complex parameters as inputs for the classification and permits the users to supervise the procedure at each step. The DCS approach was tested on the steep coastal cliff of Ancona town (Italy), called the CardetoâPassetto cliff, which is characterized by a complex fracturing and is largely affected by rockfall phenomena. The results of discontinuity orientation were validated with the field survey and compared with the ones of the FACETS plug-in of CloudCompare. In addition, the algorithm was tested and validated on regular surfaces of an anthropic wall located at the bottom of the cliff. Eventually, a kinematic analysis of rock slope stability was performed, discussing the advantages and limitations of the methods considered and making fundamental considerations on their use
A Holistic Approach to Study Groundwater-Surface Water Modifications Induced by Strong Earthquakes: The Case of Campiano Catchment (Central Italy)
Carbonate aquifers are characterised by strong heterogeneities and their modelling is often a challenging aspect in hydrological studies. Understanding carbonate aquifers can be more complicated in the case of strong seismic events which have been widely demonstrated to influence groundwater flow over wide areas or on a local scale. The 2016-2017 seismic sequence of Central Italy is a paradigmatic example of how earthquakes play an important role in groundwater and surface water modifications. The Campiano catchment, which experienced significant discharge modifications immediately after the mainshocks of the 2016-2017 seismic sequence (Mmax = 6.5) has been analysed in this study. The study area is within an Italian national park (Sibillini Mts.) and thus has importance from a naturalistic and socio-economic standpoint. The research strategy coupled long-period artificial tracer tests (conducted both before and after the main earthquakes), geochemical and discharge analyses and isotope hydrology with hydrogeological cross-sections. This study highlights how the seismic sequence temporarily changed the behaviour of the normal faults which act predominantly as barriers to flow in the inter-seismic period, with water flow being normally favoured along the fault strikes. On the contrary, during earthquakes, groundwater flow can be significantly diverted perpendicularly to fault-strikes due to co-seismic fracturing and a consequent permeability increase. The interaction between groundwater and surface water is not only important from the point of view of scientific research but also has significant implications at an economic and social level