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Novedrate, Italy

Grilli A.,University of San Marino | Graziani A.,Marche Polytechnic University | Bocci E.,eCampus University | Bocci M.,Marche Polytechnic University
Materials and Structures/Materiaux et Constructions | Year: 2016

Volumetric characteristics significantly influence the mechanical performance and the durability of bituminous mixtures. Indeed, they are important parameters to be considered in both mix design and quality control phases. Nowadays, among compaction methods, the gyratory compactor (GC) is worldwide used for bituminous mixtures. Even if there is not a universally accepted compaction procedure for cold recycling, numerous universities and road administration agencies have employed the GC especially for bituminous emulsion treated materials. However, the presence of recycled aggregate, cement, bituminous emulsion and water requires adapting the traditional volumetric parameters to these recycled materials. This paper describes the volumetric characteristics of cold recycled mixtures based on the traditional principles used for hot bituminous mixtures. In particular, the compactability and the influence of water content on a mixture containing 50 % of reclaimed asphalt stabilized with 3 % of emulsion and 2 % of cement were investigated. Moreover, closed and slotted moulds were used to study in depth the saturation process. Results showed that specimens compacted in a closed mould, at high water contents, have a bi-linear evolution of the voids content, which defines two compaction phases. In addition, laboratory compaction using a closed mould seems to simulate better the full-scale compaction procedure. Finally, the water content that allowed the saturation state to be reached at the end of the compaction process corresponded to the optimum water content of the mixture. © 2016 RILEM

Bocci E.,eCampus University | Cerni G.,University of Perugia | Colagrande S.,University of LAquila
RILEM Bookseries | Year: 2016

Recycling of waste materials is actually one of the main targets in civil engineering, because of economic and environmental features. To this aim, the field of road engineering offers many technical solutions, including the use of recycled materials from construction and demolition of civil works (C&D) in pavement layers. These materials have been investigated to be used as aggregate in asphalt concrete base layers for flexible road pavements. Different percentages (0, 15, 30 and 50 %) of C&D materials were used in order to determine the most suitable solution. The scope was to evaluate both static and dynamic mechanical properties of the mixtures. In particular, a servo-hydraulic control static press was used to run indirect tensile tests and a Nottingham Asphalt Tester was used to determine indirect tensile stiffness modulus and fatigue strength. Specimens were manufactured by mixing the aggregate with 5% of bitumen and compacted with a shear gyratory compactor to a fixed height, in order to have a constant air voids content equal to 5%. Experimental results showed that C&D materials can conveniently be used in asphalt concrete for base layers (up to maximum 30 %) without penalizing the mechanical performance of the mixture. © RILEM 2016.

Depaoli P.,LUISS University | Za S.,LUISS University | Za S.,eCampus University
Lecture Notes in Business Information Processing | Year: 2016

This conceptual paper considers the cooperative enterprise model in the light of how it can be affected by the digital world and-at the same time-of how it can positively affect both the Internet and its users. The aim of the paper is therefore twofold: (i) to consider the extent and the way in which cooperative principles are going to be affected by the transition of these firms towards ‘digital materiality’ [1]; (ii) to outline the potential implications of a diffusion of cooperative forms to Internet organizations and users. Based on the traits of this enterprise model, an emerging perspective is described whereby the ‘cooperative’ (especially if considered as a ‘service system’) has an interesting potential both as a competent actor in the domain of virtual enterprises and as a possible driver for safeguarding Internet users. © Springer International Publishing Switzerland 2016.

Cavallo M.,eCampus University | Angilletta C.,Assisted Health Residence Ville Roddolo
Aging, Neuropsychology, and Cognition | Year: 2016

Cognitive training can allow patients with Alzheimer’s disease (AD) to reinforce individual cognitive abilities. In the present case study, we investigated the generalizability of trained cognitive skills to novel tasks, and their stability over time. One AD patient underwent a structured cognitive training using the GEO (Geographical Exercise for cognitive Optimization) task, whereas eight AD patients underwent a control cognitive intervention. Participants’ performances on the GEO task, on a similar untrained cognitive task, and on a different untrained cognitive task were recorded before and after the intervention, and at the follow-up. On both the trained and the similar untrained tasks patients’ and controls’ performance significantly differed from one another. Our preliminary evidence shows that a cognitive training could allow patients to improve and maintain their performance not only on the trained task, but also on a similar task. © 2016 Informa UK Limited, trading as Taylor & Francis Group

Cattoni E.,eCampus University | Tamagnini C.,University of Perugia
Acta Geotechnica | Year: 2015

The paper presents some results from a number of dynamic FE simulations carried out to investigate the seismic response of a propped flexible retaining wall in a dry coarse-grained soil, considering two bedrock acceleration time histories as seismic input. Two different soil plasticity models have been considered in this study: an anisotropic hardening, critical-state model for cyclic/dynamic loading of sands and the classical Mohr–Coulomb elastic-perfectly plastic model with nonassociative flow rule. The results obtained allow to highlight the main features of the seismic performance of such type of flexible retaining structures and to evaluate the effects of the constitutive assumptions made on soil behavior on the predicted wall displacements and structural loads. © 2015 Springer-Verlag Berlin Heidelberg

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