Search results for "Flexural Strength"
showing 10 items of 170 documents
Induced Modification of Flexural Toughness of Natural Hydraulic Lime Based Mortars by Addition of Giant Reed Fibers
2020
Abstract Nowadays, there is a growing need to reduce the environmental impact generated by the use of inorganic materials for building applications. The aim of this work is to investigate the bio-lime based mortar flexural toughness improvement due to the addition of common reed fibers (Arundo donax L.) in order to evaluate their possible application as ductile eco-compatible prefabricated bricks or laying and joint mortars for masonry. Different sets of specimens were tested by varying the fiber weight content and the fiber length. Moreover, chemical treatments with Linseed Oil and Polyethylene glycol (PEG) were performed to improve the physical and mechanical properties of the fibers as w…
Flexural strength and microhardness of anterior composites after accelerated aging
2016
Background This study aimed to evaluate the flexural strength and microhardness of three different anterior composites after 10 000 thermocycles. Material and Methods The mechanical properties of a nano-fill composite (Filtek Ultimate Universal Restorative (FUR) (Enamel)), a nano-hybrid composite (Clearfil Majesty ES2 (ES2) (Enamel)), and a micro-hybrid composite (G Aenial Anterior (GAA)) were investigated in this study. For the microhardness test, 8-mm diameter and 2-mm thickness composite discs were used (n = 10), and for the flexural strength test, 25x2x2 mm bar-shaped specimens were prepared (n = 13). The specimens were tested at 24 h and after 10 000 thermocycles. Data were analyzed us…
Flexural and Shear Resistance of Steel Fiber–Reinforced Lightweight Concrete Beams
2014
In the present paper an analytical model is proposed that is able to determine the shear resistance of lightweight reinforced concrete beams with longitudinal bars, in the presence of reinforcing steel fibers. The model is based on the evaluation of the resistance contribution resulting from beam and arch actions. For the resistance contribution of main bars in tension, the residual bond adherence of steel bars and the crack spacing of reinforced concrete (RC) beams in the presence of fibers are considered. The contribution in terms of postcracking resistance in the tension zone of the beams is also included. The model was verified on the basis of experimental data available in the literatu…
Mechanical behavior of single-layer ceramized zirconia abutments for dental implant prosthetic rehabilitation
2013
Objectives: This study was undertaken to characterize the mechanical response of bare (as-received) and single-layer ceramized zirconia abutments with both internal and external connections that have been developed to enhanced aesthetic restorations. Material and Methods: Sixteen zirconia implant abutments (ZiReal Post®, Biomet 3i, USA) with internal and external connections have been analyzed. Half of the specimens were coated with a 0.5mm-thick layer of a low-fusing fluroapatite ceramic. Mechanical tests were carried out under static (constant cross-head speed of 1mm/min until fracture) and dynamic (between 100 and 400N at a frequency of 1Hz) loading conditions. The failure location was i…
Mechanical behavior of a sandwich with corrugated GRP core: numerical modeling and experimental validation
2014
In this work the mechanical behaviour of a core reinforced composite sandwich structure is studied. The sandwich employs a Glass Reinforced Polymer (GRP) orthotropic material for both the two external skins and the inner core web. In particular, the core is designed in order to cooperate with the GRP skins in membrane and flexural properties by means of the addition of a corrugated laminate into the foam core. An analytical model has been developed to replace a unit cell of this structure with an orthotropic equivalent thick plate that reproduces the in plane and out of plane behaviour of the original geometry. Different validation procedures have been implemented to verify the quality of t…
Paper-reinforced biomimetic cellular structures for automotive applications
2009
The aim of this work was to make and test some sandwich structures, made of biomimetic cellular cores of recycled paper. In a preliminary study some paper laminates were investigated. Then two different kinds of cores were made by simple processes, according to two natural structures (i.e. feather and honeycomb). To evaluate the mechanical properties of these new sandwiches, static flexural, flatwise and edgewise compression tests were performed.
Study of Snowboard Sandwich Structures
2005
The aim of the present research is to extend the knowledge of mechanical properties both on single components and on complete structure employed for snowboard. Flexural and torsion tests are performed to acquire important comparison parameters between snowboard sandwich structures that differ for the core material employed (wood, PVC foam core). A simplified FEM model is proposed to simulate the flexural tests of the sandwich structure showing good predictive capability.
Coded excitation speeds up the detection of the fundamental flexural guided wave in coated tubes
2016
The fundamental flexural guided wave (FFGW) permits ultrasonic assessment of the wall thickness of solid waveguides, such as tubes or, e.g., long cortical bones. Recently, an optical non-contact method was proposed for ultrasound excitation and detection with the aim of facilitating the FFGW reception by suppressing the interfering modes from the soft coating. This technique suffers from low SNR and requires iterative physical scanning across the source-receiver distance for 2D-FFT analysis. This means that SNR improvement achieved by temporal averaging becomes time-consuming (several minutes) which reduces the applicability of the technique, especially in time-critical applications such as…
Effects of natural fibres reinforcement in lime plasters (kenaf and sisal vs. Polypropylene)
2014
Nowadays the tendency to realize environment-friendly products is becoming more widespread to ensure sustainable and smart development. The synthetic fibres, frequently used, are harmful to the environment because they are non-degradable and non-renewable. Their use has resulted in an increase of oil consumption. Therefore, the possibility of replacing them with natural fibres becomes increasingly concrete confirmed by the researches and investigations carried out. In this work three lime based plasters were prepared and analysed to evaluate the influence on their performance of different fibres used as reinforcement. In particular each plaster was realised by adding to the mortar the same …
Mesocrystalline calcium silicate hydrate: A bioinspired route toward elastic concrete materials
2017
Controlled aggregation of polymer-stabilized calcium silicate hydrate nanoparticles leads to elastic cementitious materials.