Effect of Fibrillated Cellulose on Lime Pastes and Mortars

The use of nanocellulose in traditional lime-based mortars is a promising solution for green buildings in the frame of limiting the CO2 emissions resulting from Portland Cement production. The influence of the fibrillated cellulose (FC) on lime pastes and lime-based mortars was studied incorporating FC at dosages of 0%, 0.1%, 0.2% and 0.3wt% by weight of binder. The lime pastes were subjected to thermal and nitrogen gas sorption analyses to understand if FC affects the formation of hydraulic compounds and the mesoporosities volume and distribution. The setting and early hydration of the mortars were studied with isothermal calorimetry. The mechanical performances were investigated with compressive and three-point-bending tests. Furthermore, fragments resulting from the mechanical tests were microscopically studied to understand the reinforcement mechanism of the fibres. It was found that 0.3wt% of FC enhances the flexural and compressive strengths respectively by 57% and 44% while the crack propagation after the material failure is not affected.

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Three-Point Bending Tests of Zirconia Core/Veneer Ceramics for Dental Restorations

International Journal of Dentistry ◽

10.1155/2013/831976 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 31

Author(s):

Massimo Marrelli ◽

Carmine Maletta ◽

Francesco Inchingolo ◽

Marco Alfano ◽

Marco Tatullo

Keyword(s):

Surface Roughness ◽

Comparative Study ◽

Mechanical Strength ◽

Surface Hardness ◽

Mechanical Tests ◽

Bending Tests ◽

Three Point Bending ◽

Dental Restorations ◽

Modes Of Failure ◽

Cad Cam

Introduction. The mechanical strength and the surface hardness of commercially available yttrium-doped zirconia were investigated. Furthermore, a comparative study of eight different ceramic veneers, to be used for the production of two-layered all-ceramic restorative systems, was carried out.Materials and Methods. Four types of zirconia specimens were analyzed, according to a standard ISO procedure (ISO 6872). Besides, two-layered zirconia-veneer specimens were prepared for three-point bending tests.Results. A strong effect of the surface roughness on the mechanical strength of zirconia specimens was observed. Finally, a comparative study of eight commercially available veneering ceramics shows different modes of failure between the selected veneers.Conclusion. The results indicate that close attention should be paid to the preparation of zirconia-based crowns and bridges by CAD/CAM process, because surface roughness has an important effect on the mechanical strength of the material. Finally, the results of the mechanical tests on two-layered specimens represent an important support to the choice of the veneering ceramic.

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Report on laboratory tests of sandstone and porphyry for rock fracture analysis

Budownictwo i Architektura ◽

10.35784/bud-arch.1540 ◽

2020 ◽

Vol 19 (2) ◽

pp. 087-100

Author(s):

Jakub Gontarz ◽

Jacek Szulej

Keyword(s):

Tensile Strength ◽

Rock Fracture ◽

Strain Energy Release ◽

Mechanical Tests ◽

Bending Test ◽

Compression Tests ◽

Bending Tests ◽

Three Point Bending ◽

Bending Of Beams ◽

Brazilian Method

The paper presents the results of mechanical tests of three types of rocks from stone mines in Poland. Compression tests of cubic samples, three-point bending tests of beams, bending of beams with notch and testing of tensile strength using the quasi-Brazilian method were performed. Based on the tests, the compressive strength, tensile strength, Young's modulus, and Poisson's ratios were determined. The stress intensity factor and critical strain energy release rate in mode I were determined from the bending test of the notched beams. The determined values were used as parameters of computer models which are used to verify the authors’ method of predicting the crack propagation in the Abaqus FEA system.

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Validation of an Analytical Model Describing Mechanical Properties of Porous BCP Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.15 ◽

2007 ◽

Vol 361-363 ◽

pp. 15-18

Author(s):

François Pecqueux ◽

Nathalie Payraudeau ◽

Franck Tancret ◽

Jean Michel Bouler

Keyword(s):

Mechanical Properties ◽

Biphasic Calcium Phosphate ◽

Bone Substitutes ◽

Mechanical Tests ◽

Cold Isostatic Pressing ◽

Bending Tests ◽

Three Point Bending ◽

Conventional Sintering ◽

Critical Flaw ◽

Modelling Approach

Macroporous biphasic calcium phosphate bioceramics, for use as bone substitutes, have been fabricated by cold isostatic pressing and conventional sintering, using naphthalene particles as a porogen to produce macropores. The resulting ceramics, composite materials made of hydroxyapatite and β-tricalcium phosphate containing various macroporosities and microporosities, have been submitted to compression and three-point bending tests. The mechanical tests performed on the sintered ceramics tend to validate the modelling approach and its hypothesis, i.e. the material can be considered as a microporous matrix containing isolated macropores, and the critical flaw is a macropore.

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Early Hydration of Activated Belite-Rich Cement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1151.23 ◽

2019 ◽

Vol 1151 ◽

pp. 23-27 ◽

Cited By ~ 1

Author(s):

Martin Boháč ◽

Theodor Staněk ◽

Anežka Zezulová ◽

Alexandra Rybová ◽

Dana Kubátová ◽

...

Keyword(s):

Environmental Impact ◽

Analytical Approach ◽

Isothermal Calorimetry ◽

Early Hydration ◽

Cement Production ◽

X Ray ◽

Ft Ir ◽

Belite Cement

Implementation of high belite cement in cement production would have strong environmental impact in reduction CO2 emissions and saving of pure limestone deposits. The goal of the study is to describe the role of alkali and C-S-H activators on hydration of high belite cement. Analytical approach for early hydration is based on combination of isothermal calorimetry, X-ray powder diffraction in-situ, DTA-TG, FT-IR.

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The Mechanical Properties of Organic Modified Epoxy Resin

The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science ◽

10.35219/mms.2020.3.02 ◽

2020 ◽

Vol 43 (3) ◽

pp. 10-14

Author(s):

Georgel MIHU ◽

Claudia Veronica UNGUREANU ◽

Vasile BRIA ◽

Marina BUNEA ◽

Rodica CHIHAI PEȚU ◽

...

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

Epoxy Resin ◽

Epoxy Matrix ◽

Epoxy Resins ◽

Mechanical Tests ◽

Organic Modification ◽

Three Point Bending ◽

Modified Epoxy

Epoxy resins have been presenting a lot of scientific and technical interests and organic modified epoxy resins have recently receiving a great deal of attention. For obtaining the composite materials with good mechanical proprieties, a large variety of organic modification agents were used. For this study gluten and gelatin had been used as modifying agents thinking that their dispersion inside the polymer could increase the polymer biocompatibility. Equal amounts of the proteins were milled together and the obtained compound was used to form 1 to 5% weight ratios organic agents modified epoxy materials. To highlight the effect of these proteins in epoxy matrix mechanical tests as three-point bending and compression were performed.

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Investigation of the Deformation Twins on the Bending Cross Section of TA2 Titanium Sheet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.837.41 ◽

2020 ◽

Vol 837 ◽

pp. 41-45

Author(s):

Shuai Sun ◽

Kai Hua Liu

Keyword(s):

Electron Backscatter Diffraction ◽

Testing Machine ◽

Pure Titanium ◽

Titanium Sheet ◽

Bending Tests ◽

Three Point Bending ◽

Deformation Twins ◽

Ebsd Technique ◽

Backscatter Diffraction ◽

Deformation Area

In order to determine the evolution features of deformation twins for TA2 commercial pure titanium (cp-TA2), the TA2 samples were bent under different bending angles in three-point bending tests via a universal testing machine. The electron backscatter diffraction (EBSD) technique was applied to identify the grain boundaries (GBs) and twin boundaries (TBs) in the bending areas. The results reveal that the type of deformation area would effect the evolution of different deformation twins. It is inferred that the state of stress would promote the multiplication of the same type of deformation twins.

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A Study of the Flexural Behavior of Fiber-Reinforced Concretes Exposed to Moderate Temperatures

Materials ◽

10.3390/ma14133522 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3522

Author(s):

Marta Caballero-Jorna ◽

Marta Roig-Flores ◽

Pedro Serna

Keyword(s):

Steel Fiber ◽

Flexural Behavior ◽

Polypropylene Fibers ◽

Fiber Reinforced ◽

Insulation System ◽

Bending Tests ◽

Synthetic Fibers ◽

Three Point Bending ◽

Lower Performance ◽

Cracked Specimens

The use of synthetic fibers in fiber-reinforced concretes (FRCs) is often avoided due to the mistrust of lower performance at changing temperatures. This work examines the effect of moderate temperatures on the flexural strengths of FRCs. Two types of polypropylene fibers were tested, and one steel fiber was employed as a reference. Three-point bending tests were carried out following an adapted methodology based on the standard EN 14651. This adapted procedure included an insulation system that allowed the assessment of FRC flexural behavior after being exposed for two months at temperatures of 5, 20, 35 and 50 °C. In addition, the interaction of temperature with a pre-cracked state was also analyzed. To do this, several specimens were pre-cracked to 0.5 mm after 28 days and conditioned in their respective temperature until testing. The findings suggest that this range of moderate temperatures did not degrade the behavior of FRCs to a great extent since the analysis of variances showed that temperature is not always a significant factor; however, it did have an influence on the pre-cracked specimens at 35 and 50 °C.

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Utilization of Dacite as Alternative Aggregate in Asphalt Mixture

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.509.209 ◽

2012 ◽

Vol 509 ◽

pp. 209-214

Author(s):

Shao Peng Wu ◽

Pan Pan ◽

Ming Yu Chen

Keyword(s):

Asphalt Mixture ◽

Asphalt Mixtures ◽

Major Objective ◽

Widespread Application ◽

Bending Tests ◽

Three Point Bending ◽

Large Numbers ◽

Asphalt Content ◽

The Cost ◽

Cost Of Construction

With the widespread application of asphalt mixture, current demand from transportation managers for construction and maintenance of their pavement network consumes large numbers of aggregates. If agencies excessively favor to some certain kinds of excellent aggregates, the cost of construction could be considerably expensive. The major objective of this study is to determine the feasibility of utilizing dacite in asphalt mixtures. By means of Marshall, freeze-thaw, rutting and three-point bending tests, the performances of dacite and basalt asphalt mixture are compared. The results of the testing illustrate that dacite asphalt mixture is more susceptible to gradation and asphalt content than basalt asphalt mixture. Meanwhile it is showed that the performances of dacite asphalt mixture can be improved greatly with the involvement of additives including active mineral powder and cement. Furthermore, it is validated that dacite can be used as alternative aggregate in asphalt mixture.

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