Experimental validation of a theoretical model for flexural modulus of elasticity of thin cement composite

AbstractThere is a growing interest in developing cement bonded lignocellulosic fiber (LF) composites with enhanced mechanical performances. This study assessed the possibility of developing composite panels with 12 mm thickness and around 1200 kg/m3 nominal densities from ordinary Portland cements (OPC) and mixed LFs from seven different woody plants found in Hungary. Once the mixed LFs were sieved and found fine (0–0.6 mm) and medium (0.6–0.8 mm) length fibers. The optimum ratio for LF, OPC, water glass (Na2SiO3), and cement stone was found to be 1:3.5:0.7:0.07. The semi-dry process, which is a comparatively cheaper and less labor intensive technology, was used for producing the composites. After 28 days of curing, the composite panels were characterized for mechanical, physical, thermal, and morphological properties. A scanning electron microscopy (SEM) test was conducted to observe the fiber orientation in the matrix before and after the bending test, which showed the clear presence of the fibers in the composites. The FTIR (Fourier transform infrared spectroscopy) was conducted to investigate the presence of chemical compounds of LF in the composite panels. Different physical (water absorption and thickness swelling) characteristics of the composite panels were investigated. Furthermore, mechanical properties (flexural properties and internal bonding strength) of the composite panels were also found to be satisfactory. The flexural modulus and internal bonding strengths of composite panel 2 is higher than other three boards, although the flexural strength is a little lower than composite panel 1. The thermogravimetric analysis and differential thermogravimetry also indicated better thermal stability of composite panels which could be used as potential insulation panel for buildings. Graphic abstract

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Theoretical model and experimental validation for underwater oxygen extraction for realizing artificial gills

Sensors and Actuators A Physical ◽

10.1016/j.sna.2018.09.071 ◽

2018 ◽

Vol 284 ◽

pp. 103-111

Author(s):

Jongwan Lee ◽

Pil Woo Heo ◽

Taesung Kim

Keyword(s):

Theoretical Model ◽

Experimental Validation ◽

Oxygen Extraction

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Effects of Irradiation by UV- Acceleration on Mechanical Properties of Polymer Blends (Polyester: Starch)

Al-Nahrain Journal for Engineering Sciences ◽

10.29194/njes21010147 ◽

2018 ◽

Vol 21 (1) ◽

pp. 147 ◽

Cited By ~ 1

Author(s):

Sihama I. Salih ◽

Qahtan A. Hamad ◽

Safaa N. Abdul Jabbar ◽

Najat H. Sabit

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Polymer Blends ◽

Modulus Of Elasticity ◽

Unsaturated Polyester ◽

Flexural Modulus ◽

Weight Ratio ◽

Weight Fraction ◽

Elongation Percentage

This work covers mixing of unsaturated polyester (un- polyester) with starch powders as polymer blends and study the effects of irradiation by UV-acceleration on mechanical properties of its. The unsaturated polyester was mixing by starch powders at particle size less than (45 µm) at selected weight fraction of (0, 0.5, 1, 1.5, 2, 2.5 and 3%). These properties involve ultimate tensile strength, modulus of elasticity, elongation percentage, flexural modulus, flexural strength, fracture toughness, impact strength and hardness. The results illustrate decrease in the ultimate tensile strength at and elongation percentage, while increasing modulus of elasticity, with increasing the weight ratio of starch powder to 3 % weight fraction, whereas the maximum value of hardness and flexural, impact properties happened at 1 % weight fraction for types of polymer blends.

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A Theoretical Model for RF Ablation of Kidney Tissue and Its Experimental Validation

Biomedical Simulation - Lecture Notes in Computer Science ◽

10.1007/978-3-642-11615-5_13 ◽

2010 ◽

pp. 119-129 ◽

Cited By ~ 6

Author(s):

Mihaela Pop ◽

Sean R. H. Davidson ◽

Mark Gertner ◽

Michael A. S. Jewett ◽

Michael D. Sherar ◽

...

Keyword(s):

Theoretical Model ◽

Experimental Validation ◽

Kidney Tissue ◽

Rf Ablation

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Experimental Validation of a Piezoceramic Annular Plate Theoretical Model

Acoustical Imaging ◽

10.1007/978-1-4419-8772-3_73 ◽

1996 ◽

pp. 451-457 ◽

Cited By ~ 2

Author(s):

A. Iula ◽

F. R. Montero de Espinosa ◽

N. Lamberti ◽

M. Pappalardo

Keyword(s):

Theoretical Model ◽

Experimental Validation ◽

Annular Plate

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Modeling and Experimental Validation of Actuating a Bistable Buckled Beam Via Moment Input

Journal of Applied Mechanics ◽

10.1115/1.4030074 ◽

2015 ◽

Vol 82 (5) ◽

Cited By ~ 20

Author(s):

Jonathon Cleary ◽

Hai-Jun Su

Keyword(s):

Theoretical Model ◽

Experimental Test ◽

Experimental Validation ◽

Stable Equilibrium ◽

Compliant Mechanisms ◽

Computational Tool ◽

Specific Mechanism ◽

Test Setup ◽

Buckled Beams ◽

Buckled Beam

Bistable mechanisms have two stable equilibrium positions separated by a higher energy unstable equilibrium position. They are well suited for microswitches, microrelays, and many other macro- and micro-applications. This paper discusses a bistable buckled beam actuated by a moment input. A theoretical model is developed for predicting the necessary input moment. A novel experimental test setup was created for experimental verification of the model. The results show that the theoretical model is able to predict the maximum necessary input moment within 2.53%. This theoretical model provides a guideline to design bistable compliant mechanisms and actuators. It is also a computational tool to size the dimensions of buckled beams for actuating a specific mechanism.

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