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Effect of Micro Polypropylene Fibre on the Performance of Fly Ash-Based Geopolymer Concrete

: Standard Test Method for Static Modulus of Elasticity and Poisson’s Ratio of Concrete in Compression: Annual Book of ASTM Standards , DOI: 10.1520/C0469. ASTM C293-02 (2002). Standard Test Method for Flexural Strength of Concrete (Using Simple Beam with Center-Point Loading): Annual Book of ASTM Standards , pp. 1–3, DOI: 10.1520/D1635. Aulia, T.B. (2002). “Effects of polypropylene fibers on the properties of high-strength concretes.” Institutes for Massivbau and Baustoffechnologi, University Leipzig, Lacer ,, p. 7. Bagherzadeh, R., Pakravan, H

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Experimental Analysis of the Tensile Properties of Painting Canvas

-244. [23] Peirce, F. T., (1937). The geometry of cloth structure. Journal of the Textile Institute, 28(3), T45-T96. [24] Penava Ž. et al., (2014). Influence of anisotropy and yarn count on the modulus of elasticity of weft rib knitted fabric. Tekstil, 63 (9-10), 283-292. [25] Penava, Ž., et al., (2014). Determination of the Elastic Constants of a Plain Woven Fabrics by Tensile Test in Various Directions. FIBRES & TEXTILES in Eastern Europe, 22(2) 57-63. [26] Penava, Ž., Šimić, D., (2012). Analysis of the elastic constants of woven fabrics for at random

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Genetic Parameters and Genotype by Environment Interactions for Green and Basic Density and Stiffness of Pinus radiata D. Don Estimated Using Acoustics

radiata in New South Wales. Presented at 2007 Australian and New Zealand Institutes of Foresters Conference, Coffs Harbour NSW. June 2007. RAYMOND, C. A. and D. W. ANDERSON (2005): Prior landuse influences wood properties of Pinus radiata in New South Wales. New Zealand Journal of Forestry Science 35: 72-90. RAYMOND, C. A., B. JOE, R. EVANS and R. L. DICKSON (2007): Relationship between timber grade, static and dynamic modulus of elasticity and SilviScan properties for Pinus radiata in New South Wales. New Zealand Journal of Forestry

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Relationships between selected tree characteristics and the properties of juvenile wood in Scots pine (Pinus sylvestris L.)

-347. Verkasalo E. 1992. Relationships of the modulus of elasticity and the structure of Finnish Scots pine. Silva Fennica, 26(3): 155-168. Zajączkowska U. 2006. Optymalizacja kształtu i struktury drzewa według teorii jednorodnego rozkładu naprężeń [Optimization of tree structure and shape according to axiom of uniform stress]. Sylwan, 4: 53−58. Zobel B. J., Sprague J. R. 1998. Juvenile wood in forest trees. Berlin - Heidelberg - New York, Springer Verlag.

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An Experimental Investigation of the Stress-Strain Behaviour of Geopolymer Concrete

Abstract

This paper focuses on the mechanical properties and modulus of elasticity of fly ash and GGBS based geopolymer concrete. In this study an 8 molarity concentration of NaOH and alkaline liquid ratio in a ratio of 2.5 was used. This study includes the stress-strain behaviour along with the flexural strength, compressive strength and split tensile strengths for the GPC20, GPC40 and GPC60 grades. Tests were carried out on 150 mm × 150 mm × 150 mm cubes and 100 × 100 × 500 mm prisms and 150 × 300 mm cylindrical geopolymer concrete specimens. The test results not- ed the good mechanical properties and measured stress-strain relations of fly ash and GGBS based geopolymer concrete under ambient curing conditions. The elastic modulus was significantly varied with increases in the grade of the concrete. An equation was proposed to determine the modulus of elasticity based on the compressive strength of the geopolymer concrete.

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The usefulness of different wood species for bow manufacturing

Abstract

The aim of this study was to define the density and selected mechanical parameters of wood used for bow production at present, and in the past. Properties such as modulus of elasticity, bending strength and energy accumulation were determined for 11 species of wood. The analysis of results revealed that in the past, the wood used for the production of bows was not always most suitable for this application.

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Estimation Of Young’s Modulus Of Elesticity By The Form Finding Of Grid Shell Structures By The Dynamic Relaxation Method

Abstract

The paper is basically focused on the process of form finding by the dynamic relaxation method (DRM) with the aid of computational tools that enable us to make many calculations with different inputs. There are many important input values with a significant impact on the course of the calculations and the resulting displacement of a structure. One of these values is Young’s modulus of elasticity. This value has a considerable impact on the final displacement of a grid shell structure and the resulting internal forces.

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Influence of Mineral Admixtures on the Mechanical Properties of Fresh and Hardened Concrete

Abstract

This research aims to investigate the effect of introducing different mineral admixtures on the mechanical properties of concrete. The research is focused on optimizing the properties of fresh and hardened concrete, looking in particular at how factors such as slump, unit weight, air entrancement, compressive strength, tensile strength, flexural strength and modulus of elasticity are affected by different mineral admixtures in a concrete mix. Different mineral admixtures are used, namely silica fume, limestone and ultra-fine gypsum, and for the tests each mineral admixture replaced 25 % of the cement. The paper also compares the performance of the fresh and hardened properties of concrete.

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Determination of Modulus of Elasticity and Shear Modulus by the Measurement of Relative Strains

Abstract

This contribution is focused on determining the material properties (Young modulus and shear modulus) of the testing samples. The theoretical basis for determining material properties are the knowledge of linear elasticity and strength. The starting points are dependencies among the modulus of elasticity, shear modulus, normal stress and relative strain. The relative strains of the testing samples were obtained by measuring predefined load conditions using a strain-gauge bridge and the universal measurement system Quantum X MX 840. The integration of these tasks into the teaching process enhances practical and intellectual skills of students at secondary level technical universities.

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Load-Deflection Characteristics Of Steel, Polypropylene And Hybrid Fiber Reinforced Concrete Beams

Abstract

Concrete is the most widely used construction material because of its specialty of being cast into any desired shape. The main requirements of earthquake resistant structures are good ductility and energy absorption capacity. Fiber reinforced concrete possesses high flexural and tensile strength, improved ductility, and high energy absorption over the conventional concrete in sustaining dynamic loads. The aim of this paper is to compare the properties of concrete beams in which three types of fibers are added individually. Steel fibers, polypropylene fibers and hybrid fibers were added to concrete in the weight ratio of four percentages in the preparation of four beam specimens. The fourth specimen did not contain fibers and acted as a control specimen. The dimensions of the beam specimens were 150 mm × 150 mm × 700 mm. The reinforced concrete beams of M30 grade concrete were prepared for casting and testing. Various parameters such as load carrying capacity, stiffness degradation, ductility characteristics and energy absorption capacity of FRC beams were compared with that of RC beams. The companion specimens were cast and tested to study strength properties and then the results were compared. All the beams were tested under three point bending under Universal Testing Machine (UTM). The results were evaluated with respect to modulus of elasticity, first crack load, ultimate load, and ultimate deflection. The test result shows that use of hybrid fiber improves the flexural performance of the reinforced concrete beams. The flexural behavior and stiffness of the tested beams were calculated, and compared with respect to their load carrying capacities. Comparison was also made with theoretical calculations in order to determine the load-deflection curves of the tested beams. Results of the experimental programme were compared with theoretical predictions. Based on the results of the experimental programme, it can be concluded that the addition of steel, polypropylene and hybrid fibers by 4% by weight of cement (but 2.14 % by volume of cement) had the best effect on the stiffness and energy absorption capacity of the beams.

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