1,696 research outputs found
Quantification and management of rockfall risk in opencast quarrying activities
No full textRockfalls during quarrying activities are among the most critical risks associated with the various kinds of geological instabilities. Nevertheless, very few tools are available to help designers and managers correctly define these risk conditions in a rational way and to quantify the advantages that can be obtained using suitable prevention measures. For this purpose, taking into account the ‘‘Prevention through Design'' approach, it is necessary to weigh the various parameters that are involved and to define the most important factors, that is, the ones that have the most influence on rockfall phenomena. A risk evaluation system that is able to support decision makers in the critical rockfall risk assessment phase and offer them the updated information that is necessary for a continuous and dynamic operation design during exploitation activities is presented and discussed her
QuaRRi: a new methodology for rock-fall risk analysis and management in quarry exploitation
No full textRockfall is one of the most critical geological events that can affect quarrying activities. Nevertheless, few
tools are currently available to help designers and managers correctly define the risk conditions and quantify the
advantages, in terms of workers’ safety and quarry management, that can be obtained using suitable prevention
devices. For this reason it is necessary to evaluate the various parameters that are involved, and to define the most
important and which have the greatest influence on rock-fall phenomena, taking into account the Prevention
through Design approach.
A risk evaluation systemwhich is able to support decision makers in the critical rockfall risk assessment phase,
and offer decision makers the updated information that is necessary for a continuous and dynamic operation design
during exploitation activities is here presented and discussed
CERN, HL-LHC Project: numerical modelling and design challenges for the new underground facilities at Point 5
No full textThe most powerful underground particle accelerator, known as Large Hadron Collider (LHC), is located at CERN on the border between Switzerland and France. The High-Luminosity (HL-LHC) Project will increase existing facilities with new underground and shallow structures at Point 1 (ATLAS, Switzerland) and Point 5 (CMS, France). The new underground structures include a shaft, a wide cavern, 500 meters of galleries and some vertical linkage cores. This paper presents the main challenges of the Project at Point 5 describing the design and construction issues encountered for the underground structures, together with the key role of the numerical modelling in the design. The main challenges of the construction were related to the following: i) meeting the tight schedule of design and construction ii) defining design criteria i.e. calculating expected excavation-induced vibrations and minimizing the disturbance effects on the LHC where experiments were in progress; iii) excavating within a complex rock mass with several known challenging characteristics; iv) assessing the potential impact of the excavation works on the nearby existing underground structures. The excavation of the main underground works was successfully completed without any critical impact on the nearby existing underground structures. The construction phase is on track for completion within the stipulated contractual Construction Programme. The completion of the entire works is scheduled for September 2022
Numerical models for the design and construction of new underground structures at CERN (HL-LHC), Point 5
No full textThe Large Hadron Collider (LHC) is the latest, most powerful, world’s largest underground particle accelerator realized on the CERN site. High-Luminosity LHC (HL-LHC) is a new project aimed to upgrade the LHC, at Point 1 (ATLAS in Switzerland) and Point 5 (CMS in France) in order to enhance scientific progress. This paper describes the design and construction issues developed at the Point 5 for the new underground structures, located near the existing LHC tunnel. The project requires new technical infrastructure: an additional shaft with a 12 m-diameter and 60 m-height, cavern with 270 m2 cross-section, approximately 500 meters of tunnels connected to the LHC tunnel, vertical linkage cores and additional technical buildings at the surface. The geological ground model of this site lies in an area covered by Quaternary moraine with two independent aquifers. The bedrock of Molasse comprises sub-horizontal lenses of heterogeneous sedimentary rock, that is known to locally retain hydrocarbons and to have a swelling behaviour. In order to investigate the heterogeneous behaviour of the rock mass composed of several layers with different strengths, numerical calculations have been performed, under a 2D plane strain condition with RS2 9.0 FEM-software.. The purpose of using the software was to design both the rock-supports and the concrete inner lining for the tunnels and the shaft. Data from a comprehensive monitoring system with pre-defined threshold values was compared to the 2D FEM results, confirming the importance of the observational method to verify the assumptions used in the numerical modelling.
The execution of the underground works started in April 2018. The excavation of the main un-derground works has been successfully completed without any critical impact on the nearby ex-isting underground structures. The completion of the works is scheduled for September 2022
LE NUOVE OPERE SOTTERRANEE PRESSO IL CERN (HL-HLC), PUNTO 5: SFIDE PROGETTUALI ED ESECUTIVE
No full textIl Large Hadron Collider (LHC) è il più grande acceleratore di particelle situato presso il CERN di Ginevra. Trattasi di una struttura ad anello di 27 km, realizzata alla profondità di 100 m e dotata di 8 punti sperimentali in sotterraneo. In tale contesto, l’High-Luminosity (HL-LHC) è un recente progetto finalizzato al miglioramento dell’esistente acceleratore di adroni (LHC) che richiede nuove strutture sotterranee presso i punti sperimentali 1 (Svizzera) e 5 (Francia). Il presente articolo illustra le principali sfide incontrate nella progettazione e costruzione delle strutture sotterranee presso il Punto 5. Al fine di analizzare il comportamento tenso-deformativo delle differenti litologie riscontrate, la progettazione si è avvalsa di modelli numerici agli elementi finiti, fondamentali per riprodurre adeguatamente l’avanzamento delle fasi di scavo, valutare le conseguenze sulle adiacenti strutture esistenti e dimensionare i sostegni e rivestimenti. Ad oggi, le principali opere sotterranee sono state realizzate con successo e senza criticità. Il termine dei lavori è previsto per il 2022
CERN (HL-LHC): the construction experience for the underground works at Point 5
No full textHigh-Luminosity LHC (HL-LHC) is the new project aiming to upgrade the underground particle accelerator Large Hadron Collider (LHC), at Point 1 (ATLAS in Switzerland) and Point 5 (CMS in France). This paper describes the construction experience for the new underground works at Point 5, located near the existing LHC tunnel. From a geological point of view, the site lies in an area covered by Quaternary moraine with the presence of two independent aquifers. The outcrop consists of Molasse, sub-horizontal lenses of heterogeneous sedimentary rock, known in this area to locally retain hydrocarbons and to have potential swelling behaviour. The main challenges of the project were related to the limitation of vibrations and settlements induced from the excavation activities, which might degrade the operation of the in-use LHC machines. This paper presents the local geology, the monitoring data recorded and the optimizations performed during the excavations together with the contractual management aspects. The completion of the works is scheduled for September 2022
TUTELA DEL LAVORO E LIBERTA' D'IMPRESA NEI PROCESSI DI ESTERNALIZZAZIONE
No full textL’elaborato analizza le conseguenze lavoristiche della successione fra imprenditori, muovendo da una ricognizione delle varie tipologie di esternalizzazione con le relative esigenze e principali criticità.
L’indagine si concentra in primo luogo sul trasferimento d’azienda, esaminando la normativa e la giurisprudenza europee per passare poi alla disciplina di diritto interno, alle procedure sindacali e a uno specifico focus sul trasferimento delle aziende in crisi.
Successivamente l’autore si sofferma sull’appalto, prendendone in particolare considerazione gli indici di genuinità, i criteri di distinzione dalla somministrazione illecita di manodopera e la tutela delle maestranze in caso di avvicendamento fra imprese.
Da ultimo, la ricerca approfondisce le c.d. “clausole sociali”, sia di prima che di seconda generazione, valutandone la compatibilità con il diritto eurounitario e con la costituzione nonché riflettendo sui possibili rimedi in caso di loro violazione.The author analyzes the labour consequences of the succession between entrepreneurs, starting from a recognition of the various types of outsourcing with the related needs and main critical issues.
The survey focuses primarily on the transfer of businesses, examining European legislation and case-law and then moving on to internal legislation, trade union procedures and a specific focus on the transfer of companies in crisis.
The author then dwells on the contract, taking into account in particular the indications of authenticity, the criteria of distinction from the illicit administration of labour and the protection of workers in the event of turnover between companies.
Finally, the research deepens the "social clauses", both first and second generation, assessing their compatibility with European law and with the constitution and reflecting on possible remedies in case of their violation
Ultra Low Carbon Vehicles: New Parameters for Automotive Design
No full textAs the influence of vehicle emissions on our environment has become better understood, the UK government has recently placed urgent emphasis on the implementation of low carbon
technologies in the automotive industry through: the UK Low Carbon Industrial Strategy. The overall objective is to offer big incentives to consumers and support for the development of infrastructure and engineering solutions. This scheme however does not consider how the development of functional and experiential user value might drive consumer demand, contributing to the adoption of low carbon vehicles (LCVs) in the mass market.
With the emergence of the North East of England as the UK’s first specialised region for the development of ultra-low carbon vehicles (ULCVs), ONE North East, as a development agency for the region's economic and business development, and Northumbria University Ideas-lab have supported a project to facilitate innovation through the collaboration of technology, research and development (R&D) and business. The High Value Low Carbon (HVLC) project aims to envisage
new user value made possible by the integration of low carbon vehicle platforms with new process and network technologies. The HVLC consortium represents vehicle manufacturers and their suppliers as well as technology based companies and through an ongoing process of design concept generation the project offers a hub for innovation led enterprise.
Whilst new technological developments in areas such as power generation, nano materials, hydrogen fuel cells, printed electronics and networked communications will all impact on future automotive design, the mass adoption of low carbon technologies represents a paradigm shift for the motorist. This paper aims to describe how the mapping of new parameters will lead to new transport scenarios that will create the space for new collaborative research on user experiences supported by innovative technologies and related services
QuaRRi: a new methodology for rock-fall risk analysis and management in quarry exploitation
No full textRockfall is one of the most critical geological events that can affect quarrying activities. Nevertheless, few tools are currently available to help designers and managers correctly define the risk conditions and quantify the advantages, in terms of workers' safety and quarry management, that can be obtained using suitable prevention devices. For this reason it is necessary to evaluate the various parameters that are involved, and to define the most important and which have the greatest influence on rock-fall phenomena, taking into account the Prevention through Design approach. A risk evaluation systemwhich is able to support decision makers in the critical rockfall risk assessment phase, and offer decision makers the updated information that is necessary for a continuous and dynamic operation design during exploitation activities is here presented and discusse
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Matteo Maria Boiardo (1441-1494)
No full textMatteo Maria Boiardo – contemporary of Sir Thomas Malory and forerunner of Shakespeare, Spenser, Milton, Cervantes, Tolkien, and C.S. Lewis – is best known as the author of the Orlando Innamorato [Orlando in Love], a poem in ottava rima organically merging Carolingian epic and Arthurian romance. He was also a lyric and pastoral poet, playwright, and translator of classical texts into the Italian vernacular. Matteo was active in Italy during the years of 1463 throughout 1494, the year of his death
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