Search results for "Mechanics of Materials"

Flexural Behavior of Steel Fibrous Reinforced Concrete Deep Beams

2012

Experimental research was carried out regarding the flexural behavior of deep beams cast with plain and fibrous concrete with hooked steel fibers, and subjected to monotonic vertical loads. Four deep fiber-reinforced concrete beams were cast. Two of them were made of plain concrete with main and web steel reinforcements (RC), and two were made of hooked steel fiber-reinforced concrete (SFRC) with main steel reinforcements. The experimental results show the brittle behavior of reinforced deep RC members characterized by crushing of concrete struts and fracture of web steel bars. SFRC deep beams exhibit higher strength and, above all, ductility with respect to RC members due to the bridging a…

Toxicity of Dental Amalgams vs Composite Resins

2016

Ideal qualities of dental materials should include, in terms of biocompatibility, passivity towards oral tissues, so the material should not contain any leachable toxic and diffusible substances, neither release any harmful substance that can cause in time side effects, locally or generally. Even if amalgams are a group of dental materials with a long recorded history, many practitioners blame them, in contradiction with composite resins, especially for releasing free mercury into the body. On the other side, composite resins have reached great biocompatibility specifications, but also have many qualities that need more research, especially long term type.

Comportement en fatigue des composites en lin/époxy

2011

International audience; Le travail présenté s'intéresse à la caractérisation des propriétés mécaniques quasi-statiques et en fatigue d'un composite stratifié en lin/époxy. Les éprouvettes fabriquées par thermocompression ont des séquences d'empilement de 0/90° et ±45° pour les essais de traction uniaxiale et cisaillement plan respectivement. Les essais quasi-statiques révèlent une variabilité des propriétés mécaniques de l'ordre de 10%. Les essais de fatigue en traction et en cisaillement plan ont été réalisés pour des niveaux de contraintes compris entre 40 et 80% des valeurs ultimes du composite (US). L'étude des boucles d'hystérésis a mis en évidence une plastification plus importante en…

Inconsistencies in the pozzolanic strength activity index (SAI) for silica fume according to EN and ASTM

2014

Published version of an article in the journal: Materials and Structures. Also available from the publisher at: http://dx.doi.org/10.1617/s11527-014-0457-6 Open Access New supplementary cementitious materials claimed to possess pozzolan properties emerge frequently. This development is driven both by economic and environmental pressures. Properties of new materials are compared with those of materials already well known, such as silica fume. Several test methods are standardized for making such comparisons, regulated by both European (EN) and American (ASTM) standards. Standardization indicates that procedures are secured to make comparisons valid and informative. In this article the sensit…

Erratum to ‘A Robust Forward-Displacement Analysis of Spherical Parallel Robots’ [Mech. Mach. Theory, 2009, 44(12), pp. 2204–2216]

2012

Electrical Transport and Confocal Raman Studies of Electrochemically Modified Individual Carbon Nanotubes

2003

Heavy-Ion-Induced Defects in Degraded SiC Power MOSFETs

2023

Cathodoluminescence spectroscopy is used to investigate the formation of point- and extended defects in SiC power MOSFETs exposed to heavy-ions. Devices showing single event leakage current (SELC) effects are analysed and compared to pristine samples. Common luminescence peaks of defect centers localized in the thermal-SiO2 are identified, together with peaks at the characteristic wavelength of extended defects.

Highly Sensitive Polarization Rotation Measurement through a High‐Order Vector Beam Generated by a Metasurface

2020

The precise determination of the polarization state of light is fundamental for a vast variety of applications in remote sensing, astronomy, optics and terahertz technology, to name just a few. Typically, polarization characterization is performed by using a combination of multiple optical devices such as beam splitters, polarizers, and waveplates. Moreover, to achieve high-precision, balanced photodetectors and lock-in amplifiers are employed, thus contributing to increasing system complexity. Here, a technique for polarization rotation measurements with a dynamic range of 180° and a sensitivity of about 10−2 degrees is realized using a properly designed metasurface. Such device generates …