Search results for "Structural engineering"
showing 10 items of 1998 documents
Neutronic and photonic analysis of the water-cooled Pb17Li test blanket module for ITER-FEAT
2002
Abstract Within the European Fusion Technology Program, the Water-Cooled Lithium Lead (WCLL) DEMO breeding blanket line was selected in 1995 as one of the two EU lines to be developed in the next decade, in particular with the aim of manufacturing a Test Blanket Module (TBM) to be implemented in ITER. This specific goal has been maintained also in ITER-FEAT program even if the general design parameters of the TBMs have reported some changes. This paper is focused on the investigation of the WCLL-TBM nuclear response in ITER-FEAT through detailed 3D-Monte Carlo neutronic and photonic analyses. A 3D heterogeneous model of the most recent design of the WCLL-TBM has been set-up simulating reali…
On the nuclear response of the water-cooled Pb-17Li test blanket module for ITER-FEAT
2003
Abstract Within the European Fusion Technology Programme, the Water-Cooled Lithium Lead (WCLL) DEMO breeding blanket line was selected in 1995 as one of the two EU lines to be developed in the next decades, in particular with the aim of manufacturing a Test Blanket Module (TBM) to be tested in ITER-FEAT. The present paper is focused on the study of the WCLL-TBM nuclear response in ITER-FEAT, being specifically oriented to the investigation of the local effects due to the typical C-shaped tubes of the breeder zone, since they could play a pivotal role in the module-relevant thermo–mechanical design. A 3D heterogeneous model of the WCLL-TBM, realistically simulating its new lay out and taking…
Thermomechanical analysis supporting the preliminary engineering design of DONES target assembly
2018
Abstract The design of the Demo Oriented NEutron Source (DONES) is the main objective of the Work Package Early Neutron Source (WPENS) of EUROfusion Power Plant Physics and Technology (PPPT) programme. DONES is an IFMIF-based neutron source with the goal of testing and qualifying candidate materials to be used in DEMO and future fusion power plants. In the framework of these activities, a research campaign has been carried out at the University of Palermo, in close cooperation with ENEA labs, in order to assess the thermomechanical performances of the DONES target system, endowed with an integrated Target Assembly (TA) when it undergoes the thermomechanical loads typical of its nominal oper…
A tool for a first analysis of architectural façades
1997
Abstract This work presents a tool for analysing the figurative structure of architectural facades. The procedure begins by singling out the elementary shapes which make up the facade image; it detects and identifies them as “area objects”, even if present in combination in virtual or mental form and groups them into classes of equal objects. A second step is the analysis of the inner structure of the classes: equidistant, arithmetical and geometrical sequences, or alternate distances are distinguished. The procedure ends by singling out the symmetries which structure the facade image and displaying them, pointing out their implied hierarchy through a thickness differentiation.
On the improvement of monumental structure safety: a case study
2006
The present paper deals with the problem of the preservation of the monumental patrimony and discusses a practical application. The analysis methodology based on modern dynamic identification techniques was used for a monumental church in the historic area of Catania (Italy). The dynamic response of the church was measured in terms of accelerations, by means of vibration tests in situ. The numerical analyses highlighted the vulnerability of the drum dome system. Hence interest focused on this part of the building. A reduced scale model of the above system was built to be subjected to dynamic tests on a shaking table at the ENEA laboratory at Casaccia (Rome). Different kinds of reversible de…
Computer Simulation Paradigm Regarding the Structure and Mechanical Characteristics of Human Long Bones
2013
Given the complex form of the long bones, a quality method of geometrical modeling which provides a good result is that of the 3D modeling by reconstruction, using the principles of reverse engineering. One of the important problems that shall be taken into consideration while modeling is the one concerning the real structure of the bones. This aspect presents a lot of importance because from the point of view of the mechanical behavior, the bones are neither homogenate structures. In this paper a study of the long bones structures is undergone, and in relation to the modelated element (the human tibia) it is divided in areas (called constructive-anatomical entities) of different mechanical…
Structural analysis of the back supporting structure of the DEMO WCLL outboard blanket
2017
Abstract Within the framework of EUROfusion R&D activities an intense research campaign has been carried out at the University of Palermo, in close cooperation with ENEA Brasimone, in order to investigate the thermo-mechanical performances of the outboard segment Back-Supporting Structure (BSS) of the DEMO Water-Cooled Lithium Lead breeding blanket (WCLL). In particular, the configuration of the outboard segment BSS, purposely set-up by the WCLL project team during 2015 according to the blanket “multi-module system” concept, has been taken into account in order to study its steady state thermo-mechanical behaviour, paying attention to the simulation of both modules-BSS and BSS-vacuum vessel…
An efficient framework for the elasto-plastic reliability assessment of uncertain wind excited systems
2016
Abstract In this paper a method to efficiently evaluate the reliability of elastic-perfectly plastic structures is proposed. The method is based on combining dynamic shakedown theory with Subset Simulation. In particular, focus is on describing the shakedown behavior of uncertain elasto-plastic systems driven by stochastic wind loads. The ability of the structure to shakedown is assumed as a limit state separating plastic collapse from a safe, if not elastic, state of the structure. The limit state is therefore evaluated in terms of a probabilistic load multiplier estimated through solving a series of linear programming problems posed in terms of the responses of the underlying linear elast…
Hydraulic Characterization of a Pervious Concrete for Deep Draining Trenches
2018
Reduction in pore water pressure is an useful strategy to improve the stability of slopes. Deep draining trenches can be used for this purpose. For the realization of deep trenches, the usual conventional construction techniques are not adequate and the use of adjacent vertical panels, built by means of the methods well-established for diaphragm walls, is necessary. However, unbonded materials (i.e., gravels) cannot be used, because the excavation of a panel adjacent to one already built will cause instability. For this scope a bonded material such as pervious concrete can be used. It must have high permeability; filtering capacity, in order to prevent internal erosion of the soil in which …
Volume change behaviour of a compacted scaly clay during cyclic suction changes
2010
The research presented in this paper focuses on the investigation and modelling of the volume change response of compacted tectonised clay samples subjected to several wetting and drying cycles in controlled-suction oedometers. Oedometer tests were carried out under different values of constant vertical net stress, and wetting and drying cycles were performed varying applied matric suction between 10 and 800 kPa. The investigation was complemented with a study of the material microstructure to support the interpretation of the overall mechanical response. At a microscopic level, the material is characterized by different types of particle assemblages, scales, and clay aggregates. One of th…