Search results for " costruzione."
showing 7 items of 477 documents
Thermo-Mechanical Behaviour of Flax-Fibre Reinforced Epoxy Laminates for Industrial Applications
2015
The present work describes the experimental mechanical characterisation of a natural flax fibre reinforced epoxy polymer composite. A commercial plain woven quasi-unidirectional flax fabric with spun-twisted yarns is employed in particular, as well as unidirectional composite panels manufactured with three techniques: hand-lay-up, vacuum bagging and resin infusion. The stiffness and strength behaviours are investigated under both monotonic and low-cycle fatigue loadings. The analysed material has, in particular, shown a typical bilinear behaviour under pure traction, with a knee yield point occurring at a rather low stress value, after which the material tensile stiffness is significantly r…
Effect of NaOH Treatment on Properties of Phoenix Sp. Fiber
2016
The aim of this paper is to investigate the effect of an alkali treatment on physical, chemical, mechanical, and morphological properties of Phoenix Sp. fibers. The use of natural fibers as reinforcement in polymer composites requires a deep investigation to understand their behavior and which treatment is more appropriate to improve the quality of the untreated material. For this reason, fibers were extracted from the petioles of the Phoenix Sp. plant and they were treated with NaOH solution in different weight concentrations (5%, 10%, and 15%). The mechanical behavior was investigated through tensile test on single fiber at different gauge length (20 mm, 30 mm, 40 mm, 50 mm, and 60 mm). C…
A Quantitative Analysis of the Thermoelastic Effect in CFRP Composite Materials
2010
In this study the thermoelastic signal from carbon fibre-reinforced plastic (CFRP) laminates is investigated. A comparison between the theoretical and experimental values of the thermoelastic signal is reported, with the theoretical predictions obtained from two different quantitative models. These models are based on the classic thermoelastic effect law extended to the case of orthotropic materials (by using the mesomechanical or bulk approach), and the modified law assuming that the surface resin-rich layer behaves as a strain witness of the laminate. It is found that the theoretical predictions of the two models can be strongly and differently influenced by the intrinsic orthotropy of ca…
Engine/Transmission Matching
2014
This chapter deals with the forecasting of vehicle performance on the road, according to the installed engine. It begins with Section 1, which shows the calculation of the resistance to motion, that is, the forces that the vehicle must overcome to advance on flat roads and uphill. The calculation excludes accidental resistance in curves because it is not essential for predicting the behavior of the vehicle on the road. Section 2 begins with the power characteristic, the forecast by traction–speed and power–speed diagrams, calculation of gear ratios, and then passing to the limits to the estimated acceleration, feature consumption, and distance. This chapter concludes with a section on the d…
Analisi fotoelastica delle tensioni residue nel vetro
2010
ANALISI DELLE TENSIONI RESIDUE NEL VETRO MEDIANTE LA FOTOELASTICITÀ CON FRANGE DI RIFERIMENTO
2011
L’analisi delle tensioni residue nei vetri viene di solito effettuata con metodi fotoelastici dato che il vetro è un materiale birifrangente. Questa memoria considera l’automazione del cosiddetto "test fringes” metodo che si basa sull’impiego di un compensatore di Babinet o di un provino inflesso. In particolare si propongono due metodi automatici basati sull’impiego del metodo del centro frangia in luce monocromatica e sull’impiego della fotoelasticità RGB in luce bianca. I metodi proposti possono efficacemente sostituire i metodi manuali.