scholarly journals Exploratory research in the creation of mono-structured low-combustibility fibreboards

2020 ◽  
Author(s):  
А.А. Леонович ◽  
Е.А. Свиридо ◽  
М.Г. Глазунова
Keyword(s):  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Statistical Models ◽  
Wood Fiber ◽  
Fire Retardant ◽  
General Purpose ◽  
Binder Content ◽  
Exploratory Research ◽  
Diphosphonic Acid ◽  
Technological Factors

Антипирен на основе гидроксиэтилидендифосфоновой кислоты вводили в древесное волокно (смесь березы и осины), массу обрабатывали меламинокарбамидоформальдегидным связующим, формировали ковер и прессовали огнезащищенные древесноволокнистые плиты средней плотности. С использованием экспериментально-статистических моделей изучали влияние продолжительности прессования, содержания антипирена и связующего на свойства плит по показателям прочности при изгибе, модулю упругости, набуханию и горючести. Проведен анализ и показана на уровне требований стандартов возможность изготовления плит общего назначения или конструкционных пониженной горючести путем варьирования в установленных пределах рецептурными и технологическими факторами. A fire retardant based on hydroxyethylidene diphosphonic acid was introduced into wood fiber (a mixture of birch and aspen), the mass was treated with a melaminecarbamide-formaldehyde binder, a carpet was formed, and fire-resistant mediumdensity fiberboards were pressed. Using experimental statistical models, we studied the effect of pressing duration, fire retardant and binder content on the properties of plates in terms of flexural strength, modulus of elasticity, swelling and flammability. The analysis is carried out and the possibility of manufacturing plates of general purpose or structural low combustibility by varying prescription and technological factors within the established limits is shown at the level of standards requirements.

scholarly journals The Performance of Filava-Polysiloxane, Silres® H62C Composite in High Temperature Application

2021 ◽  
Vol 5 (6) ◽  
pp. 144
Author(s):  
Klaudio Bari ◽  
Thozhuvur Govindaraman Loganathan
Keyword(s):  
High Temperature ◽  
Flexural Strength ◽  
Flexural Modulus ◽  
Fire Retardant ◽  
Bending Test ◽  
Ongoing Research ◽  
Flexural Testing ◽  
Temperature Application ◽  
High Temperature Tensile ◽  
In Fire

The research aim is to investigate the performance of novel enriched mineral fibres (Filava) in polysiloxane SLIRES H62 resin. Specimens were manufactured using a vacuum bagging process and oven cured at 250 °C. Specimens were prepared for flexural testing according to BS EN ISO 14125:1998 to obtain flexural strength, modulus, and elongation. The mechanical strength was compared to similar composites, with the aim of determining composite performance index. The flexural modulus (9.7 GPa), flexural strength (83 MPa), and flexural strain (2.9%) were obtained from a three-point bending test. In addition, the study investigates the thermal properties of the composite using a state-of-art Zwick Roell high temperature tensile rig. The results showed Filava/Polysiloxane Composites had an ultimate tensile strength 400 MPa, Young’s modulus 16 GPa and strain 2.5% at 1000 °C, and no smoke and ash were observed during pyrolysis. Ongoing research is currently taking place to use Filava-H62 in fire-retardant enclosure for lithium-ferro-phosphate Batteries used in electric trucks.

scholarly journals Influence of Hybrid Fibers on Toughness Behavior of High Strength Flowing Concrete

2011 ◽  
Vol 57 (3) ◽  
pp. 249-260 ◽  
Author(s):  
Eethar Thanon Dawood ◽  
Mahyuddin Ramli
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Hybrid Composite ◽  
High Strength ◽  
Steel Fibers ◽  
Hybrid Fibers ◽  
Static Modulus ◽  
Static Modulus Of Elasticity ◽  
Strength And Toughness

Abstract This study investigates the use of steel fibers and hybrid composite with a total fibers content of 2% on the high strength flowing concrete and determines the density, compressive strength, static modulus of elasticity, flexural strength and toughness indices for the mixes. The results show that the inclusion of more than 0.5% of palm fibers in hybrid fibers mixes reduces the compressive strength. The hybrid fibers can be considered as a promising concept and the replacement of a portion of steel fibers with palm fibers can significantly reduce the density, enhance the flexural strength and toughness. The results also indicates that the use of hybrid fibers (1.5 steel fibers + 0.5% palm fibers) in specimens increases significantly the toughness indices and thus the use of hybrid fibers combinations in reinforced concrete would enhance their flexural toughness & rigidity and enhance their overall performances

scholarly journals Effect of Recycled Coarse Aggregates in Properties of Concrete

2008 ◽  
Vol 3 (4) ◽  
pp. 130-137 ◽  
Author(s):  
R Kumutha ◽  
K Vijai
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Coarse Aggregate ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Split Tensile Strength ◽  
Coarse Aggregates ◽  
The Cost

The properties of concrete containing coarse recycled aggregates were investigated. Laboratory trials were conducted to investigate the possibility of using recycled aggregates from the demolition wastes available locally as the replacement of natural coarse aggregates in concrete. A series of tests were carried out to determine the density, compressive strength, split tensile strength, flexural strength and modulus of elasticity of concrete with and without recycled aggregates. The water cement ratio was kept constant for all the mixes. The coarse aggregate in concrete was replaced with 0%, 20%, 40%, 60%, 80% and 100% recycled coarse aggregates. The test results indicated that the replacement of natural coarse aggregates by recycled aggregates up to 40% had little effect on the compressive strength, but higher levels of replacement reduced the compressive strength. A replacement level of 100% causes a reduction of 28% in compressive strength, 36% in split tensile strength and 50% in flexural strength. For strength characteristics, the results showed a gradual decrease in compressive strength, split tensile strength, flexural strength and modulus of elasticity as the percentage of recycled aggregate used in the specimens increased. 100% replacement of natural coarse aggregate by recycled aggregate resulted in 43% savings in the cost of coarse aggregates and 9% savings in the cost of concrete.

scholarly journals Effect of Aggregate Type and Specimen Configuration on Concrete Compressive Strength

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 625 ◽  
Author(s):  
Sherif Yehia ◽  
Akmal Abdelfatah ◽  
Doaa Mansour
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
American Concrete Institute ◽  
Recycled Aggregates ◽  
Concrete Compressive Strength ◽  
Split Tensile Strength ◽  
Standard Size ◽  
Noticeable Effect ◽  
The Difference

In this paper, concrete mixes utilizing two sizes of natural aggregate and two sources of lightweight and recycled aggregates were used to investigate the effect of aggregate type and specimen size and shape on the compressive strength of concrete. In addition, samples from ready-mix concrete producers with different strengths were evaluated using standard size cylinders and cubes. Results were obtained on the 7th, 28th, and 90th day. In addition, flexural strength, split tension, and modulus of elasticity were evaluated on the 28th and 90th day. Statistical analyses were conducted to examine the significance of the difference between the compressive strength values for each two mixes using tests of hypotheses. Moreover, other mechanical properties as a function of compressive strength were discussed and compared to those predicated by the American Concrete Institute (ACI) specifications. Results indicate specimen shape has a noticeable effect on the compressive strength as the Cylinder/Cube ratio on the 90th day was ranging between 0.781 and 0.929. The concrete compressive strength and modulus of elasticity were significantly affected by the aggregate type. The flexural strength and split tensile strength were less affected by the aggregate type, which was also confirmed by the values predicted with the ACI equations.

Effect of Binder Content on the Slip Rheology and Green Properties of Slip Cast Alumina

2019 ◽  
Vol 798 ◽  
pp. 177-181
Author(s):  
Kritkaew Somton ◽  
Pitak Laoratanakul ◽  
Ryan McCuiston
Keyword(s):  
Flexural Strength ◽  
Physical And Mechanical Properties ◽  
Casting Process ◽  
Binder Content ◽  
Green Density ◽  
Optimal Amount ◽  
Solids Loading ◽  
Maximum Value ◽  
Slip Cast ◽  
Scanning Electron

The rheology of A96% alumina slips and the physical and mechanical properties of slip cast samples were studied. The slips had a constant solids loading of 40 wt% alumina and a polyvinyl alcohol (PVA) content of 0-3 wt%, as a binder. The rheological behavior and viscosity of the slips were examined to determine the flowability of the slips necessary for the casting process. The slips were prepared by ball milling and the bend bar samples were cast in plaster molds. The green densities and the flexural strength of the bars were measured, and the fracture surfaces were examined by scanning electron microscopy. It was found that the slip viscosity increased with an increase of PVA content. The green flexural strength also increased to a maximum value of 0.52 MPa with increasing PVA up to 2 wt%. The further addition of PVA decreased the flexural strength. The green density did not significantly change with the PVA content, however the samples produced using 3 wt% PVA showed the lowest percentage of theoretical density of 41%. The fracture surface of the 3 wt% PVA sample showed numerous large pores compared with the other samples. Therefore, in this study it was concluded that there is in optimal amount of PVA to produce the highest green density and flexural strength of cast samples. Excess PVA reduced the flowability of the slip and resulted in excess porosity, which decreased the green density and deteriorated the flexural strength.

scholarly journals Effects of the Amount of Fly Ash Modified by Stearic Acid Compound on Mechanical Properties, Flame Retardant Ability, and Structure of the Composites

2020 ◽  
Vol 2020 ◽  
pp. 1-6 ◽  
Author(s):  
Tuan Anh Nguyen
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Fly Ash ◽  
Flexural Strength ◽  
Stearic Acid ◽  
Flame Retardant ◽  
Burning Rate ◽  
Thermal Power ◽  
Waste Product ◽  
Fire Retardant

Fly ash, a waste product from thermal power plants, is one of the good alternatives for use as a filler in polymers, especially in flame retardants. Fly ash is an environmentally friendly fire retardant additive for composites, used in place of conventional flame retardant additives such as halogenated organic compounds, thus promoting environmental safety. In this study, fly ash was modified with stearic acid to improve adhesion at the polymers interface and increase compatibility. Fly ash was studied at various volumes (5, 10, and 20 wt.% fly ash) used in this study to synthesize fly ash-epoxy composites. The results show that the tensile strength, flexural strength, compressive strength, and impact strength of these synthetic materials increase when fly ash is modified to the surface, compressive strength: 197.87 MPa, flexural strength: 75.20 MPa, impact resistance: 5.77 KJ/m2, and tensile strength: 47.89 MPa. Especially, the fire retardant properties are improved at a high level, with a modified 20% fly ash content: the burning rate of 16.78 mm/min, minimum oxygen index of 23.2%, and meet the fire protection standard according to UL 94HB with a burning rate of 8.09 mm/min. Scanning electron microscopy (SEM) and infrared spectroscopy were used to analyze the morphological structure of fly ash after being modified and chemically bonded with epoxy resin background.

Effect of Polypropylene Fiber on Strength and Flexural Properties of Concrete Containing Silica Fume

2011 ◽  
Vol 346 ◽  
pp. 30-33
Author(s):  
Hong Wei Wang
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Silica Fume ◽  
Modulus Of Elasticity ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Flexural Modulus ◽  
Polypropylene Fiber ◽  
Flexural Properties ◽  
Fiber Volume

A designed experimental study has been conducted to investigate the effect of polypropylene fiber on the compressive strength and flexural properties of concrete containing silica fume, a large number of experiments have been carried out in this study. The flexural properties include flexural strength and flexural modulus of elasticity. On the basis of the experimental results of the specimens of six sets of mix proportions, the mechanism of action of polypropylene fiber on compressive strength, flexural strength and flexural modulus of elasticity has been analyzed in details. The results indicate that there is a tendency of increase in the compressive strength and flexural strength, and the flexural modulus of elasticity of concrete containing silica fume decrease gradually with the increase of fiber volume fraction.

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