Effect of volume fraction and aspect ratio of Agave fiber Cantula Roxb against compressive strength and direct tensile strength

Concrete has high compressive strength, but low tensile strength, bending strength, toughness, low resistance to cracking, and brittle fracture characteristics. To overcome these problems, fiber-reinforced concrete, in which the strength of concrete is improved by inserting fibers, is being used. Recently, high-performance fiber-reinforced cementitious composites (HPFRCCs) have been extensively researched. The disadvantages of conventional concrete such as low tensile stress, strain capacity, and energy absorption capacity, have been overcome using HPFRCCs, but they have a weakness in that the fiber reinforcement has only 2% fiber volume fraction. In this study, slurry infiltrated fiber reinforced cementitious composites (SIFRCCs), which can maximize the fiber volume fraction (up to 8%), was developed, and an experimental study on the tensile behavior of SIFRCCs with varying fiber volume fractions (4%, 5%, and 6%) was carried out through direct tensile tests. The results showed that the specimen with high fiber volume fraction exhibited high direct tensile strength and improved brittleness. As per the results, the direct tensile strength is approximately 15.5 MPa, and the energy absorption capacity was excellent. Furthermore, the bridging effect of steel fibers induced strain hardening behavior and multiple cracks, which increased the direct tensile strength and energy absorption capacity.

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Effect of Metakaolin and PVA Fibres on the Workability and Mechanical Properties of Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.935.188 ◽

2014 ◽

Vol 935 ◽

pp. 188-192 ◽

Cited By ~ 2

Author(s):

Sadaqat Ullah Khan ◽

Muhd Fadhil Nuruddin ◽

Nasir Shafiq ◽

Tehmina Ayub

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Aspect Ratio ◽

Volume Fraction ◽

Splitting Tensile Strength

Locally produced metakaolin (MK) as the cement replacing material and PVA fibres has been used. The effect on workability and on the mechanical properties of concrete has been investigated. Total fifteen (15) mixes of concrete have been examined using MK 5 to 10% and PVA fibres of aspect ratio 45, 60, 90 and 120 with 1% volume fraction. Three (03) mixes without PVA fibre have been used as control mixes. For each mix, test for slump, cube compressive strength and splitting tensile strength has been performed. It has been found that MK and PVA fibres causes decrease in slump but use of MK and PVA fibres together improves the workability. The use of MK and PVA fibres has advantageous in increasing compressive strength and splitting tensile strength.

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The Effects of Nanosilica on Mechanical Properties and Fracture Toughness of Geopolymer Cement

Polymers ◽

10.3390/polym13132178 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2178

Author(s):

Cut Rahmawati ◽

Sri Aprilia ◽

Taufiq Saidi ◽

Teuku Budi Aulia ◽

Agung Efriyo Hadi

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Tensile Strength ◽

Compressive Strength ◽

Agricultural Waste ◽

X Ray ◽

Geopolymer Cement ◽

Direct Tensile ◽

Direct Tensile Strength ◽

Geopolymer Paste

Nanosilica produced from physically-processed white rice husk ash agricultural waste can be incorporated into geopolymer cement-based materials to improve the mechanical and micro performance. This study aimed to investigate the effect of natural nanosilica on the mechanical properties and microstructure of geopolymer cement. It examined the mechanical behavior of geopolymer paste reinforced with 2, 3, and 4 wt% nanosilica. The tests of compressive strength, direct tensile strength, three bending tests, Scanning Electron Microscope-Energy Dispersive X-ray (SEM/EDX), X-ray Diffraction (XRD), and Fourier-transform Infrared Spectroscopy (FTIR) were undertaken to evaluate the effect of nanosilica addition to the geopolymer paste. The addition of 2 wt% nanosilica in the geopolymer paste increased the compressive strength by 22%, flexural strength by 82%, and fracture toughness by 82% but decreased the direct tensile strength by 31%. The microstructure analysis using SEM, XRD, and FTIR showed the formation of calcium alumina-silicate hydrate (C–A–S–H) gel. The SEM images also revealed a compact and cohesive geopolymer matrix, indicating that the mechanical properties of geopolymers with 2 wt% nanosilica were improved. Thus, it is feasible for nanosilica to be used as a binder.

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Performance of Ultra High Strength Concrete Expose to High Rise Temperature

Annales de Chimie Science des Matériaux ◽

10.18280/acsm.450411 ◽

2021 ◽

Vol 45 (4) ◽

pp. 351-359

Author(s):

Noor Alhuda Sami Aljabbri ◽

Mohammed Noori Hussein ◽

Ali Abdulmohsin Khamees

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Fire Resistance ◽

High Strength Concrete ◽

High Strength ◽

Splitting Tensile Strength ◽

Explosive Spalling ◽

Strength Concrete ◽

Direct Tensile ◽

Direct Tensile Strength

Fire or high temperature is a serious issue to ultra-high-strength concrete (UHSC). Strength reduction of UHPCs may amount to as high as 80 percent after exposure to 800℃. A sum of four UHSC mixes was synthesized and evaluated in this study after getting exposed to extreme temperatures that reach 1000°C. Steel and polypropylene (PP) fibers were used in this experiment. A total of four mixes were made of UHSC without fibres as a control mix (UHSC-0), UHSC with 2% steel fibres (UHSC-S), UHSC with 2% PP fibres (UHSC-P) and UHSC with 1% steel fibres + 1% PP fibres (UHSC-SP). Workability, direct tensile strength, compressive strength, and splitting tensile strength were examined. Particularly, emphasis was devoted to explosive spalling since UHPCs are typically of compact structure and hence more prone to explosive spalling than other concretes. It was determined that the mixture UHSC-SP had high fire resistance. Following exposure to 1000℃, this mixture preserved a residual compressive strength of 36 MPa, splitting tensile strength of 1.62 MPa and direct tensile strength of 0.8 MPa. On the other hand, UHSC-P also had good fire resistance while UHSC-0 and UHSC-S experienced explosive spalling after heating above 200ᴼC. The incorporation of steel fibers in UHSC-S and UHSC-SP mixtures reveals higher tensile and compressive strength findings at different elevated temperatures as compared to UHSC-0 and UHSC-P. In addition, the result of direct tensile strength appears to be lower than splitting tensile strength at different raised temperatures.

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A Direct Method to Evaluate the Tensile Strength of Polyolefin Fiber Cement-Based Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.586.99 ◽

2012 ◽

Vol 586 ◽

pp. 99-102

Author(s):

Ta Yuan Han ◽

Wei Ting Lin ◽

An Cheng ◽

Chin Cheng Huang

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Silica Fume ◽

Fiber Length ◽

Direct Method ◽

Impact Resistance ◽

Strength Properties ◽

Fiber Content ◽

Direct Tensile ◽

Direct Tensile Strength

This study is aimed to evaluate the tensile strength of cement-based composites which comprise polyolefin fibers and silica fume in the mixes. Material variables include water-cementitious ratio, dosage of silica fume, steel fiber length and dosage. Test results indicate that the compressive strength and direct tensile strength of specimens for fiber length of 25 mm are higher than that of 50 mm. The strength properties increase with increasing fiber content. Incorporation of fiber and silica fume in composites achieves significantly higher increase in compressive strength and direct tensile strength than only use of fiber or silica fume. In addition, the compressive strength, splitting tensile strength, direct tensile strength and impact resistance are fairly correlated. It contributes that the fiber content influences crack arresting ability and the silica fume influences interfacial bonding effectively.

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Experimental Research on Tensile Strength of Premixed Concrete at Early Ages

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.687 ◽

2014 ◽

Vol 556-562 ◽

pp. 687-691 ◽

Cited By ~ 1

Author(s):

Xiao Fen Li ◽

Ping Ren

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Exact Results ◽

Direct Tension ◽

Splitting Strength ◽

Experimental Apparatus ◽

Structural Applications ◽

Direct Tensile ◽

Direct Tensile Strength ◽

The Relationship

The splitting tensile method for the tensile strength of concrete is usually used in structural applications, so it is great important in the investigating the relation between the direct tensile strength and the splitting strength. But the relationship between the splitting strength and the direct tensile strength is not consolidatly confirmed at home and abroad. In order to obtain the exact results, the experimental apparatus for concrete of the direct tension are designed, which resolves the difficulty of ensuring that the load is truly axial. Tests of the direct tension are performanced on three different concrete mixes (C20,C40,C60) at 3, 7, 14 , 28 and 60 days and the test data do not scatter. The relations between the tensile strength and the cube compressive strength are obtained and a formula for investigating the relation between the direct tensile strength and the splitting strength are proposed.

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Effect of Fiber Length on Direct Tensile and Impact Strength of Cmentitious Materials Containing Silica Fume

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.37 ◽

2015 ◽

Vol 764-765 ◽

pp. 37-41

Author(s):

Wei Ting Lin

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Silica Fume ◽

Fiber Length ◽

Steel Fiber ◽

Impact Resistance ◽

Cementitious Materials ◽

Individual Use ◽

Direct Tensile ◽

Direct Tensile Strength

This study is aimed to evaluate the tensile strength and impact resistance of cementitious materials which comprise steel fibers and silica fume in the mixes. Material variables include water-binder ratio, dosage of silica fume, steel fiber length and dosage. A designed tensile strength was used to perform the direct tensile in this study. Test results indicate that the compressive strength, splitting tensile strength and direct tensile strength of specimens for fiber length of 60 mm are higher than that of 35 mm. The inclusion of fibers in specimens containing silica fume has higher compressive and tensile strength; and lower impact resistance than the specimens made with silica fume. Incorporation of steel fiber and silica fume in composites achieves significantly higher increase in compressive strength, splitting tensile strength, and direct tensile strength than only individual use of steel fiber or silica fume and decrease in impact resistance than only individual use of steel fiber. Finally, the proposed direct tensile testing method is suitable for determining the tensile strength of fiber reinforce cementitious materials and generating the tensile stress-strain curves easily.

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Strength Development of Concrete Incorporating Metakaolin and PVA Fibres

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.567.505 ◽

2014 ◽

Vol 567 ◽

pp. 505-510 ◽

Cited By ~ 1

Author(s):

Sadaqat Ullah Khan ◽

Muhd Fadhil Nuruddin ◽

Nasir Shafiq

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Aspect Ratio ◽

Flexural Strength ◽

Volume Fraction ◽

Splitting Tensile Strength ◽

Strength Development ◽

Increasing Trend ◽

Better Than

Study has been conducted to investigate the effect of aspect ratio and volume fraction of PVA fibres on the mechanical properties of concrete. Total eighteen (18) mixes of concrete have been examined using metakaolin up to 5% and PVA fibres of aspect ratio 45, 60, 90 and 120 with volume fraction 1 to 2%. Compressive strength, splitting tensile strength and flexural strength at 7 days and 28 days have been determined to check the effect of volume fraction and the aspect ratio of PVA fibres. It has been found that 2% volume fraction is better than 1% and there is increasing trend up to a certain value of aspect ratio in the strengths of concrete.

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