Análisis experimental del comportamiento mecánico de elementos de madera de pino silvestre de pequeña escuadría sometidos a compresión transversal a las fibras = Experimental analysis of the mechanical behavior of small squad pine wood elements subjected to cross-fiber compression

ResumenEn numerosos detalles estructurales de construcciones realizadas con madera, el esfuerzo de compresión transversal a las fibras juega un papel muy importante y en muchas ocasiones condiciona su diseño. En este trabajo se analiza el comportamiento a compresión de piezas de madera de pino silvestre de pequeña escuadría sometidas a un esfuerzo de compresión transversal a las fibras y se han obtenido unos valores medios para la tensión de rotura y el módulo de elasticidad de 4,20 MPa y 305,86 MPa, respectivamente.AbstractIn many structural details of buildings made of wood, the transverse compression stress to the fibers plays a very important role and often determines its design. In this work, the compression behavior of small pine wood pieces subjected to a cross - compressive stress to the fibers is analyzed and mean values for the tensile strength and the modulus of elasticity of 4,20 MPa and 305.86 MPa, respectively.

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Small-size jatropha seed biochar extracted from microwave pyrolysis: Optimization of its biocomposites mechanical properties by mixture design

BioResources ◽

10.15376/biores.16.3.4716-4730 ◽

2021 ◽

Vol 16 (3) ◽

pp. 4716-4730

Author(s):

Perry Law Nyuk Khui ◽

Md. Rezaur Rahman ◽

Kuok King Kuok ◽

Muhammad Khusairy Bin Bakri ◽

Muhammad Adamu ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Polylactic Acid ◽

Modulus Of Elasticity ◽

Experimental Testing ◽

Mixture Design ◽

Microwave Pyrolysis ◽

Mean Values ◽

Poly Ethylene ◽

Jatropha Seed

Microwave pyrolysis of finely ground jatropha seed biochar was used as bio-filler to develop biocomposites. Effects influencing the mechanical properties of the biocomposites were investigated based on varied material ratio. Ratios by percentage of weight were determined by D-optimal (custom) mixture design using the Stat Ease “Design Expert”. The mechanical properties, such as tensile strength, modulus of elasticity, and microhardness, were the dependent variables (response). Bio-filler content was optimised to attain the overall best mechanical properties for the biocomposites. The optimized biocomposite that showcased good tensile strength, modulus of elasticity, and microhardness biocomposite ratio’s predicted mechanical properties mean values were tensile strength (9.53 MPa), modulus of elasticity (0.730 GPa), and microhardness (20.4 HV) for polylactic acid and biofiller mixture; and tensile strength (7.92 MPa), modulus of elasticity (0.668 GPa), and microhardness (18.7 HV) for polylactic acid, biofiller, and poly(ethylene-alt-maleic anhydride) mixture. Models generated by the mixture design showcased some degree of noise and error present; however, the outcome through the optimization step was generally reliable for predicting the mechanical properties. Additional data gathered through experimental testing and replicates could improve the reliability of the model.

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Investigating Tensile Behavior of Sustainable Basalt–Carbon, Basalt–Steel, and Basalt–Steel-Wire Hybrid Composite Bars

Sustainability ◽

10.3390/su131910735 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10735

Author(s):

Mohammadamin Mirdarsoltany ◽

Alireza Rahai ◽

Farzad Hatami ◽

Reza Homayoonmehr ◽

Farid Abed

Keyword(s):

Tensile Strength ◽

Elastic Modulus ◽

Mechanical Behavior ◽

Modulus Of Elasticity ◽

Hybrid Composite ◽

Glass Fibers ◽

Steel Wire ◽

Composite Fibers ◽

Steel Wires ◽

Steel Bars

One of the main disadvantages of steel bars is rebar corrosion, especially when they are exposed to aggressive environmental conditions such as marine environments. One of the suggested ways to solve this problem is to use composite bars. However, the use of these bars is ambiguous due to some weaknesses, such as low modulus of elasticity and linear behavior in the tensile tests. In this research, the effect of the hybridization process on mechanical behavior, including tensile strength, elastic modulus, and energy absorbed of composite bars, was evaluated. In addition, using basalt fibers because of their appropriate mechanical behavior, such as elastic modulus, tensile strength, durability, and high-temperature resistance, compared to glass fibers, as the main fibers in all types of composite hybrid bars, was investigated. A total of 12 hybrid composite bars were made in four different groups. Basalt and carbon T300 composite fibers, steel bars with a diameter of 6 mm, and steel wires with a diameter of 1.5 mm were used to fabricate hybrid composite bars, and vinyl ester 901 was used as the resin. The results show that, depending on composite fibers used for fabrication of hybrid composite bars, the modulus of elasticity and the tensile strength increased compared to glass-fiber-reinforced-polymer (GFRP) bars by 83% to 120% and 6% to 26%, respectively. Moreover, hybrid composite bars with basalt and steel wires witnessed higher absorbed energy compared to other types of hybrid composite bars.

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The Behavior of Strength Properties from Three Different Tree Boles of Aras in Sarawak

Journal of Civil Engineering Science and Technology ◽

10.33736/jcest.94.2011 ◽

2011 ◽

Vol 2 (2) ◽

pp. 48-52

Author(s):

Gaddafi Ismaili ◽

Badorul Hisham Abu Bakar ◽

Khairul Khuzaimah Abdul Rahim

Keyword(s):

Moisture Content ◽

Physical Properties ◽

Compressive Stress ◽

Modulus Of Elasticity ◽

Basic Density ◽

Strength Properties ◽

Modulus Of Rupture ◽

Compression Stress ◽

Mean Values ◽

Green Condition

Aras had been selected and tested in small clear specimens. Sampling of test specimens are made from three sections of the tree bole namely from bottom, middle, and top parts. This paper looks into the information of strength properties from three sections of sampled. The strength properties test required are the modulus of rupture, modulus of elasticity and compression stress parallel to grain. Meanwhile, the physical properties' test referred to moisture content and basic density. The testing conducted in two different conditions of the trees, which were referred to green and air-dry condition. It was found that the average mean values for modulus of rupture, modulus of elasticity and compressive stress parallel to grain tested at green condition were 47.52N/mm2, 6358.56N/mm2 and 22.42N/mm2 respectively meanwhile at air-dry condition were 70.49N/mm2, 8217.64N/mm2 and 34.07N/mm2 respectively. Meanwhile, the average mean values for moisture content at green condition were 83.34% whilst at the air-dry condition were 12.33%. Basic density remains unchanged from both conditions.

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Roller Compacted Concrete with Recycled Concrete Aggregate for Paving Bases

Sustainability ◽

10.3390/su12083154 ◽

2020 ◽

Vol 12 (8) ◽

pp. 3154 ◽

Cited By ~ 2

Author(s):

Hedelvan Emerson Fardin ◽

Adriana Goulart dos Santos

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Modulus Of Elasticity ◽

Splitting Tensile Strength ◽

Recycled Concrete ◽

Concrete Aggregate ◽

Recycled Concrete Aggregate ◽

Roller Compacted Concrete ◽

Flexural Tensile Strength ◽

Mechanical And Physical Properties

This research aimed to investigate the mechanical and physical properties of Roller Compacted Concrete (RCC) used with Recycled Concrete Aggregate (RCA) as a replacement for natural coarse aggregate. The maximum dry density method was adopted to prepare RCC mixtures with 200 kg/m³ of cement content and coarse natural aggregates in the concrete mixture. Four RCC mixtures were produced from different RCA incorporation ratios (0%, 5%, 15%, and 30%). The compaction test, compressive strength, splitting tensile strength, flexural tensile strength, and modulus of elasticity, porosity, density, and water absorption tests were performed to analyze the mechanical and physical properties of the mixtures. One-way Analysis of Variance (ANOVA) was used to identify the influences of RCA on RCC’s mechanical properties. As RCA increased in mixtures, some mechanical properties were observed to decrease, such as modulus of elasticity, but the same was not observed in the splitting tensile strength. All RCCs displayed compressive strength greater than 15.0 MPa at 28 days, splitting tensile strength above 1.9 MPa, flexural tensile strength above 2.9 MPa, and modulus of elasticity above 19.0 GPa. According to Brazilian standards, the RCA added to RCC could be used for base layers.

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Mechanical Behavior for some Cobalt Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1114.9 ◽

2015 ◽

Vol 1114 ◽

pp. 9-12

Author(s):

Alexandru Ghiban ◽

Brandusa Ghiban ◽

Cristina Maria Borţun ◽

Nicolae Serban ◽

Mihai Buzatu

Keyword(s):

Tensile Strength ◽

Chemical Composition ◽

Mechanical Behavior ◽

Mechanical Characteristics ◽

Fractographic Analysis ◽

Cobalt Alloys ◽

Dental Alloys ◽

Bending Tests ◽

Longitudinal Modulus

Four compositions of some usually commercial dental alloys were investigated in order to determine the mechanical characteristics and fractographic analysis of tensile and bending tests surfaces. A correlation between chemical composition (either molybdenum or molybdenum and chromium contents) and mechanical characteristics (longitudinal modulus, tensile strength and elongation) were finally done.

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Thermal, structural, and mechanical effects of nanofibrillated cellulose in polylactic acid filaments for additive manufacturing

BioResources ◽

10.15376/biores.15.4.7954-7964 ◽

2020 ◽

Vol 15 (4) ◽

pp. 7954-7964

Author(s):

Diego Gomez-Maldonado ◽

Maria Soledad Peresin ◽

Christina Verdi ◽

Guillermo Velarde ◽

Daniel Saloni

Keyword(s):

Tensile Strength ◽

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Modulus Of Elasticity ◽

Manufacturing Process ◽

Thermal Characterization ◽

Nanofibrillated Cellulose ◽

Small Decrease ◽

The Matrix

As the additive manufacturing process gains worldwide importance, the need for bio-based materials, especially for in-home polymeric use, also increases. This work aims to develop a composite of polylactic acid (PLA) and nanofibrillated cellulose (NFC) as a sustainable approach to reinforce the currently commercially available PLA. The studied materials were composites with 5 and 10% NFC that were blended and extruded. Mechanical, structural, and thermal characterization was made before its use for 3D printing. It was found that the inclusion of 10% NFC increased the modulus of elasticity in the filaments from 2.92 to 3.36 GPa. However, a small decrease in tensile strength was observed from 55.7 to 50.8 MPa, which was possibly due to the formation of NFC aggregates in the matrix. This work shows the potential of using PLA mixed with NFC for additive manufacturing.

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Influence of the surface treatment of tire rubber residues added in mortars

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952008000200001 ◽

2008 ◽

Vol 1 (2) ◽

pp. 113-120 ◽

Cited By ~ 11

Author(s):

A. C. Marques ◽

J. L. Akasaki ◽

A. P. M. Trigo ◽

M. L. Marques

Keyword(s):

Mechanical Properties ◽

Aqueous Solution ◽

Tensile Strength ◽

Compressive Strength ◽

Surface Treatment ◽

Water Absorption ◽

Modulus Of Elasticity ◽

Tire Rubber ◽

Flow Test ◽

Made In

In this work it was evaluated the influence tire rubber addition in mortars in order to replace part of the sand (12% by volume). It was also intended to verify if the tire rubber treatment with NaOH saturated aqueous solution causes interference on the mechanical properties of the mixture. Compressive strength, splitting tensile strength, water absorption, modulus of elasticity, and flow test were made in specimens of 5cmx10cm and the tests were carried out to 7, 28, 56, 90, and 180 days. The results show reduction on mechanical properties values after addition of tire rubber and decrease of the workability. It was also observed that the tire rubber treatment does not cause any alteration on the results compared to the rubber without treatment.

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Characterizing hydro-thermal compression behavior of aspen wood strands

Holzforschung ◽

10.1515/hf.2009.111 ◽

2009 ◽

Vol 63 (5) ◽

Cited By ~ 10

Author(s):

Cheng Zhou ◽

Gregory D. Smith ◽

Chunping Dai

Keyword(s):

Elevated Temperatures ◽

Oriented Strand Board ◽

Transverse Compression ◽

Aspen Wood ◽

Thermal Compression ◽

Compression Behavior ◽

End Products ◽

Regression Approach ◽

Fundamental Understanding ◽

Strain Function

Abstract Wood-based composites, such as oriented strand board, are typically manufactured by consolidating mats of resinated wood elements under heat and pressure. During this process, the temperature and moisture content distributions within the mat greatly affect the properties of end products. To improve the fundamental understanding of mat consolidation during hot-pressing, a model is established to investigate the transverse compression behavior of aspen wood strands for a variety of combinations of temperatures (20–200°C) and moisture contents (0–15%). A regression approach is used to obtain the modulus-temperature-moisture relationship. In addition, elevated temperatures and moistures are found to influence the strain function of wood strands, which was previously assumed to be independent of these factors.

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Basic and Grade Stress for Some Timber in Sarawak

Journal of Civil Engineering Science and Technology ◽

10.33736/jcest.92.2011 ◽

2011 ◽

Vol 2 (2) ◽

pp. 35-38

Author(s):

Gaddafi Ismaili ◽

Badorul Hisham Abu Bakar ◽

Khairul Khuzaimah Abdul Rahim

Keyword(s):

Exotic Species ◽

Modulus Of Elasticity ◽

Acacia Mangium ◽

Wood Properties ◽

Strength Properties ◽

Indigenous Species ◽

Medium Density ◽

Compression Stress ◽

Strength Group ◽

Fast Growing Species

Strength properties’ tests are conducted in the small clear sample. This paper aim to acquire the basic and grade stresses of some fast growing species thus identifies its strength group. Thus, the information of wood properties from different species and condition are acquired from strength property's test. The required information namely, bending parallel to the grain, compression stress parallel to grain, shear parallel to grain and modulus of elasticity. The condition of the trees which is referred to green and air-dry condition. Three different species which are referred to exotic species of Acacia mangium and indigenous species of Aras. The results from the study indicated that, Acacia mangium classified under the strength group SG5, whilst Aras was classified under the strength group SG7. The timber is of medium density Light Hardwood ranging from 0.37-0.52g/cm3 air-dry condition.

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Effect of Recycled Coarse Aggregates in Properties of Concrete

Journal of Green Building ◽

10.3992/jgb.3.4.130 ◽

2008 ◽

Vol 3 (4) ◽

pp. 130-137 ◽

Cited By ~ 1

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.

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