Fracture Behaviour of Concrete with Reactive Magnesium Oxide as Alternative Binder

This research evaluates the fracture behavior of concrete with reactive magnesium oxide (MgO). Replacing cement with MgO is an attractive option for the concrete industry, mainly due to sustainability benefits and reduction of shrinkage. Four different MgO’s from Australia, Canada, and Spain were used in the concrete mixes, as a partial substitute of cement, at 5%, 10%, and 20% (by weight). The fracture toughness (KI) intensity factor and the stress–strain softening parameters of the wedge split test were evaluated after 28 days. The experimental results showed that the replacement of cement with MgO reduced the fracture energy between 13% and 53%. Moreover, the fracture energy was found to be correlated with both compressive strength and modulus of elasticity. A well-defined relationship between these properties is important for an adequate prediction of the non-linear behavior of reinforced concrete structures made with partial replacement of cement with MgO.

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Macroscopic Fracture Behaviour of CrN Hard Coatings Evaluated by X-Ray Diffraction Coupled with Four-Point Bending

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.272 ◽

2013 ◽

Vol 768-769 ◽

pp. 272-279

Author(s):

Mario Stefenelli ◽

Angelika Riedl ◽

Juraj Todt ◽

Matthias Bartosik ◽

Rostislav Daniel ◽

...

Keyword(s):

Fracture Stress ◽

Fracture Behavior ◽

Fracture Behaviour ◽

Hard Coatings ◽

Relevant Parameter ◽

X Ray Diffraction ◽

X Ray ◽

Four Point Bending ◽

Macroscopic Fracture ◽

Crn Coatings

Fracture behavior of hard nanocrystalline coatings decisively influences the lifetime and performance of coated tools. In this work, residual stresses in as-deposited and annealed CrN coatings deposited at 350 °C using bias voltages of −40 V and −120 V were evaluated using synchrotron X-ray diffraction coupled with four-point bending. The stress development during the bending experiments was used to analyse fracture properties of the coatings. The results indicate that an annealing at 550 °C does not deteriorate the fracture behavior of the coatings prepared using −40 V bias. In the case of −120 V bias coatings, the residual stress relaxation after the thermal treatment is accompanied by a fracture strain decrease and a fracture stress increase. The as-deposited and annealed CrN coatings deposited using −120 V bias exhibit significantly large fracture strains in comparison with −40 V samples. Finally the results document that the fracture stress may not be the only relevant parameter when comparing different coating systems. Also the strain at fracture can be considered as significant indicator of the coating fracture response. Methodologically, the results indicate that in-situ X-ray diffraction coupled with four point bending can be effectively used to evaluate macroscopic fracture behaviour of hard coatings.

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Test Study of Fracture Mechanical Properties of Reactive Powder Concrete with Additives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.904.3 ◽

2014 ◽

Vol 904 ◽

pp. 3-6 ◽

Cited By ~ 1

Author(s):

Zhi Gang Yin

Keyword(s):

Mechanical Properties ◽

Energy Release Rate ◽

Fracture Energy ◽

Energy Release ◽

Release Rate ◽

Fracture Behavior ◽

Fracture Model ◽

Reactive Powder Concrete ◽

Critical Crack Length ◽

Reactive Powder

The different influencing regular of fly-ash fractiontype of fibre (steel fibre and polypropylene fibre) and fibre fraction on the mechanical property and fracture behavior of Reactive Powder Concrete (PRC) are studied. Fracture mechanical properties of RPC is researched in double-K fracture model and fracture energy release rate G . Test results show that the crack propagation of RPC with steel fibers is limited. Its fracture toughness and pre-critical crack length is largely enhanced. Double-K fracture model and fracture energy release rate G are consistent with describing the fracture behavior of RPC.

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Microstructure evolution and microimpact performance of Sn–Ag–Cu solder joints under thermal cycle test

Journal of Materials Research ◽

10.1557/jmr.2010.0162 ◽

2010 ◽

Vol 25 (7) ◽

pp. 1312-1320 ◽

Cited By ~ 2

Author(s):

Y.L. Huang ◽

K.L. Lin ◽

D.S. Liu

Keyword(s):

Fracture Energy ◽

Microstructure Evolution ◽

Thermal Cycle ◽

Fracture Behavior ◽

Solder Ball ◽

Solder Joints ◽

Whisker Formation ◽

Structural Variations ◽

Before And After ◽

Ball Joints

The microstructure and microimpact performance of Sn1Ag0.1Cu0.02Ni0.05In (SAC101NiIn)/AuNi/Cu solder ball joints were investigated after a thermal cycle test (TCT). The joints show complete bulk fracture behavior before TCT. Moreover, TCT facilitated interfacial fracture behavior with lower fracture energy. The intermetallic compounds (IMCs) formed in the solder joints before and after TCT were investigated. TCT induces a variety of structural variations in the solder joints, including slipping bands, whisker formation, the squeezing of the IMC layer, the formation of cavities, the rotation and pop-up of grain, and the deformation and rotation of the entire joint. The variations in fracture behavior induced by TCT are correlated with the structural variations in the solder joints.

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FRACTURE BEHAVIOR OF Zr-BASED BULK METALLIC GLASS UNDER IMPACT LOADING

International Journal of Modern Physics B ◽

10.1142/s0217979206041355 ◽

2006 ◽

Vol 20 (25n27) ◽

pp. 4359-4364 ◽

Cited By ~ 1

Author(s):

HYUNG-SEOP SHIN ◽

KI-HYUN KIM ◽

SANG-YEOB OH

Keyword(s):

Fracture Toughness ◽

Crack Initiation ◽

Fracture Energy ◽

Impact Loading ◽

Static Loading ◽

Fracture Behavior ◽

Loading Rate ◽

Shear Bands ◽

Maximum Load ◽

Cu Alloy

The fracture behavior of a Zr -based bulk amorphous metal under impact loading using subsize V-shaped Charpy specimens was investigated. Influences of loading rate on the fracture behavior of amorphous Zr - Al - Ni - Cu alloy were examined. As a result, the maximum load and absorbed fracture energy under impact loading were lower than those under quasi-static loading. A large part of the absorbed fracture energy in the Zr -based BMG was consumed in the process for crack initiation and not for crack propagation. In addition, fractographic characteristics of BMGs, especially the initiation and development of shear bands at the notch tip were investigated. Fractured surfaces under impact loading are smoother than those under quasi-static loading. The absorbed fracture energy appeared differently depending on the appearance of the shear bands developed. It can be found that the fracture energy and fracture toughness of Zr -based BMG are closely related with the extent of shear bands developed during fracture.

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Use of Thermoplastic Polymer in Mortar Composites to Improve its Chloride Penetration Resistance

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.22.33 ◽

2016 ◽

Vol 22 ◽

pp. 33-44 ◽

Cited By ~ 3

Author(s):

M. Omrane ◽

A.S. Benosman ◽

M. Mouli ◽

Y. Senhadji

Keyword(s):

Reinforced Concrete ◽

Flexural Strength ◽

Portland Cement ◽

Penetration Depth ◽

Concrete Structures ◽

Chloride Ion ◽

Chloride Penetration ◽

Partial Replacement ◽

Total Charge ◽

Reinforced Concrete Structures

This paper presents a study of the resistance to chloride penetration of blended Portland cement mortar containing thermoplastic waste polymer polyethylene terephthalate (TWPET). Composite TWPET-mortars are often presented as the materials of the future in reason of their potential for innovation and advantages that offer. In fact, the use of TWPET percentages as a cement substitution reduces energy costs; address problems related to environmental pollution by CO2 emissions and repairs various reinforced concrete structures. Blended Portland cement (CPJ) is partially replaced with TWPET at the amounts of 2%, 4% and 6% by weight of cementitious materials. Chloride penetration depth of full and partial immersions in 3% NaCl solution, rapid chloride permeability test (RCPT) after 28, 90 and 120 days, sorptivity, leaching test and flexural strength of thermoplastic-mortar composites (TMCs) were determined. Test results reveal that the resistance to chloride penetration of TMCs improves substantially with partial replacement of CPJ with TWPET and without significantly affecting the flexural strength in tap water. The chemical resistance is higher with an increase in the replacement level. So, sorptivity, the chloride ion penetration depth, apparent chloride ion diffusion coefficient, the total charge passed in coulombs and leached depth measurements of the TMCs are much smaller than those of reference mortar. The formations which appear such as different calcium salts were determined by X-ray diffraction. These results take into account the use of waste plastics in the manufacture of mortars modified which can be both recommended for preventing the chloride-induced corrosion of the steel in various reinforced concrete structures and participate greatly in the environment preservation.

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On the fracture behaviour of magnesium oxide bi-crystals

Philosophical Magazine ◽

10.1080/14786436108243308 ◽

1961 ◽

Vol 6 (62) ◽

pp. 195-200 ◽

Cited By ~ 34

Author(s):

A. R. C. Westwood

Keyword(s):

Magnesium Oxide ◽

Fracture Behaviour

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A fracture energy based constitutive model for the analysis of reinforced concrete structures under cyclic loading

Computer Methods in Applied Mechanics and Engineering ◽

10.1016/j.cma.2008.06.017 ◽

2008 ◽

Vol 197 (51-52) ◽

pp. 4745-4762 ◽

Cited By ~ 30

Author(s):

Wei He ◽

Y.-F. Wu ◽

K.M. Liew

Keyword(s):

Reinforced Concrete ◽

Cyclic Loading ◽

Constitutive Model ◽

Fracture Energy ◽

Concrete Structures ◽

Reinforced Concrete Structures

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Non-Destructive Vibration Tests on Reinforced Concrete Structures

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.660.186 ◽

2015 ◽

Vol 660 ◽

pp. 186-191 ◽

Cited By ~ 2

Author(s):

Marina Lute

Keyword(s):

Reinforced Concrete ◽

Dynamic Response ◽

Concrete Beams ◽

Concrete Structures ◽

Reinforced Concrete Beams ◽

Reinforced Concrete Structures ◽

Linear Behavior ◽

Non Linear ◽

Vibration Tests ◽

Non Destructive

The purpose of this paper is looking at the dynamic response of existing reinforced concrete structures which have possibly sustained various levels of damage, a set of tests need to be identified that will be able to detect damage and quantify the damage if damage exists. In this work it is presented a further study on the effect of damage on the behavior of reinforced concrete beams. In particular, the non-linear behavior of these beams is considered once significant cracking has been introduced, outlining the stage of testing carried out in dynamic field.

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