Effect of Sand Size on Mechanical Performance of Cement-Based Composite Containing PVA Fibers and Nano-SiO2

Both finer sand and nanoparticles have a filler effect on mechanical performance of cement-based composite. In this paper, the influence of sand size in mechanical performance of cement-based composites, containing polyvinyl alcohol fiber (PVA) and nano-SiO2 (NS), was investigated. The studied mechanical performance, included compressive, flexural, tensile strength, and fracture toughness. A 0.9% volumetric percentage of PVA and a 2% NS mass content were used to make cement-based composites with a 0.38 w/b. Silica sand with four sand size ranges (380–830 μm, 212–380 μm, 120–212 μm and 75–120 μm) was adopted as fine aggregate. The 28-day curing was conducted for all specimens under 20 °C and 95% humidity. It is concluded that the finer sand decreased workability and mechanical strength of PVA-reinforced composites containing NS. However, this reduction was very limited for the sand particles less than 380 µm. The ultimate tensile stain, fracture toughness, and energy were decreased as sand size declined. In addition, the fracture performance of the composites was greatly dependent on fracture energy.

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Effect of Water Absorption Rates on Fracture Toughness of Sisal Textile Fiber Reinforced Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.213 ◽

2005 ◽

Vol 297-300 ◽

pp. 213-218 ◽

Cited By ~ 1

Author(s):

Yang Bae Jeon ◽

Do Won Seo ◽

Jae Kyoo Lim

Keyword(s):

Fracture Toughness ◽

Water Absorption ◽

Mechanical Performance ◽

Natural Fiber ◽

Natural Fibers ◽

Compact Tension ◽

Polymer Matrices ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced

Using natural fibers that are inexpensive, lightweight and biodegradable, as the reinforcement for composites is difficult due to their poor interfacial properties between hydrophilic fiber and hydrophobic polymer matrices. It is necessary to evaluate fracture toughness of natural fiber reinforced composites according to water absorption rates to improve mechanical performance of those. In this study, compact tension fracture test was conducted to evaluate fracture toughness with the various specimens. The value of fracture toughness has the tendency to decrease as water absorption rate increases. And different surface treatment methods and different polymer matrices have influence on the value of fracture toughness.

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Crushing Performance of Ultra-Lightweight Foam Concrete with Fine Particle Inclusions

Applied Sciences ◽

10.3390/app9050876 ◽

2019 ◽

Vol 9 (5) ◽

pp. 876 ◽

Cited By ~ 2

Author(s):

Yu Song ◽

David Lange

Keyword(s):

Mechanical Performance ◽

High Volume ◽

Fine Aggregate ◽

Micro Computed Tomography ◽

Foam Concrete ◽

Recycled Fine Aggregate ◽

High Volume Fly Ash ◽

Cellular Microstructure ◽

Strength Material ◽

Sand Particles

Foam concrete is a low-density controlled strength material that can potentially be used for accommodating different types of particles—recycled fine aggregate being an example. The paste matrix of this material has a cellular microstructure, and bulk performance is readily affected by the inclusion of fines. To study the effect of inclusion of fines on mechanical performance and foam structure of foam concrete, a group of 0.55 g/cm3 foam–sand composite mixtures with high-volume fly ash replacement are investigated. The elastic modulus is measured by a vibrational frequency test. The crushing mechanics are determined by the load-displacement response from a penetration test. The effect of particle inclusion on the foam concrete microstructure is characterized using micro computed tomography. The results indicate that use of fine-graded sand particles at a small dosage simultaneously reduces cement content and enhances the crushing performance, however poor material performance is observed for a high sand content. The cellular structure of the foam–sand composite, and thus its mechanical behavior, can be substantially diminished by larger sand particles, especially when the particle size is larger than the voids in foam.

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Cement Composites for High Temperature Applications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.982.154 ◽

2014 ◽

Vol 982 ◽

pp. 154-158 ◽

Cited By ~ 5

Author(s):

Dana Koňáková ◽

Eva Vejmelková ◽

Veronika Spedlova ◽

Kirill Polozhiy ◽

Robert Černý

Keyword(s):

High Temperature ◽

Thermal Resistance ◽

Mechanical Performance ◽

Fire Hazard ◽

Silica Sand ◽

Cement Composites ◽

Reinforced Composites ◽

The Matrix ◽

Aluminous Cement ◽

Temperature Applications

Fiber reinforced composites designed for better thermal resistance, which can be used in constructions with a higher fire hazard, are studied. The matrix of studied composite is based on aluminous cement, because of its proved higher thermal resistance than ordinary Portland cement. Basalt sand is used as alternative aggregate replacing silica sand, and basalt fibers are employed for an improvement of mechanical performance. The presented analysis of basic physical properties, mechanical, hygric and thermal properties shows that basalt is an appropriate material for cement based composites for high temperature applications.

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Fracture Toughness of the Natural Fiber‐Reinforced Composites: A Review

Mechanical and Dynamic Properties of Biocomposites ◽

10.1002/9783527822331.ch16 ◽

2021 ◽

pp. 293-304

Author(s):

Haasith Chittimenu ◽

Monesh Pasupureddy ◽

Chandrasekar Muthukumar ◽

Senthilkumar Krishnasamy ◽

Senthil Muthu Kumar Thiagamani ◽

...

Keyword(s):

Fracture Toughness ◽

Natural Fiber ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced

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Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

Journal of Composite Materials ◽

10.1177/0021998321999458 ◽

2021 ◽

pp. 002199832199945

Author(s):

Jong H Eun ◽

Bo K Choi ◽

Sun M Sung ◽

Min S Kim ◽

Joon S Lee

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Photoelectron Spectroscopy ◽

Mechanical Performance ◽

Epoxy Composites ◽

Scanning Calorimetry ◽

Internal Damage ◽

Impact Tests ◽

Flexural Tests ◽

The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

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