scholarly journals Bending Strength Analysis of Durian and Coconut Timber Laminated Beam

2020 ◽  
Vol 9 (4) ◽  
pp. 1319-1322
Keyword(s):  
Bending Strength ◽  
Thin Layers ◽  
Strength Analysis ◽  
Laminated Beams ◽  
Laminated Beam ◽  
Alternative Material ◽  
Weak Side ◽  
Timber Engineering

Durian timber grows well in the Gunungpati area, although its use is still limited to the needs of light construction. Lamination (glulam) is a combination of one or more kinds of materials and the materials are made into relatively thin layers glued together to form a larger dimension. Timber engineering experiment was conducted by creating a laminated beam made of Durian and coconut timber, with a composition of coconut - Durian – coconut. The purpose of this study was to determine the bending strength of a composition of coconut – durian – coconut laminated beam in strengthening the weak side of the durian timber. Coconut timber was used to reinforce durian timber because the weight of coconut timber is relatively larger compared to Durian timber. Durian laminated beam with coconut timber reinforcement on the top and bottom can be used as an alternative material to improve the bending strength durian timber. Lamination technology was able to increase the bending strength of Durian timber with laminated beams by 12.6% from the average bending strength of 36.68 MPa durian timber, laminated beams into bending strength of 41.30 MPa.

scholarly journals Knitted Meshes for Reinforcing Building Composites

2019 ◽  
Vol 27 (4(136)) ◽  
pp. 102-111
Author(s):  
Zbigniew Mikołajczyk ◽  
Katarzyna Pieklak ◽  
Aleksandra Roszak
Keyword(s):  
Concrete Beam ◽  
Bending Strength ◽  
Relative Elongation ◽  
Testing Machine ◽  
Strength Analysis ◽  
Knitted Fabrics ◽  
Three Point Bending ◽  
Concrete Mass ◽  
Frp Composites ◽  
Technical Textiles

Modern technical textiles, including knitted fabrics, are widely used in the construction industry. Regarding textiles in concrete reinforcement, methods based on shredded fibres, meshes, reinforcing mats, woven textiles and knitted DOStapes are frequently used as underlays of concrete constructions. Textiles are also used in the reinforcement of fibrous FRP composites. The research presented focused on producing composites made of MapeiMapefill concrete mass with reinforcement in the form of three variants of knitted meshes made of 228 tex polyamide threads, polypropylene threads of 6.3 tex and 203 tex glass threads, as well as identification of their mechanical properties. The mesh variant made of glass fibre is especially noteworthy, as its strength is more than three times higher than that of polyamide meshes. At the same time, a very small relative elongation of 3% is observed for this variant of knitted fabric, which is a desired property regarding the comparatively low stretching extension of concrete. In the process of making the composites, the adhesion of the concrete mass to the surface of the threads was analyzed. For this purpose, a "Sopro HE449" type agent was used. Composite beams were subjected to a three-point bending strength analysis on a testing machine. The results of strength measurements of the composites obtained prove that those with glass fibres demonstrate a threefold increase in strength compared to the original concrete beam.

FLEXURAL STRENGTH ANALYSIS OF LAMINATED BAMBOO SLATS (BAMBUSA ARUNDINACEA) FOR CONSTRUCTING A SMALL FISHING BOAT SHELLS

2015 ◽  
Vol 157 (B1) ◽  
Author(s):  
H Supomo ◽  
D Manfaat ◽  
A Zubaydi
Keyword(s):  
Flexural Strength ◽  
Shell Thickness ◽  
Tectona Grandis ◽  
Epoxy Adhesive ◽  
Strength Analysis ◽  
Fishing Boat ◽  
Laminated Bamboo ◽  
Alternative Material ◽  
Press Method

Because of the advantages of bamboo and the decreasing supply of teak, as a material for the construction of small Indonesian fishing boats, bamboo becomes an alternative substitute for teak as a common material to construct this type of boat. There are many bamboo species and populations in Indonesia which form the basis for selecting an advanced alternative material to construct fishing boats. This study discusses the mechanical properties of laminated bamboo slats, with a polyamide epoxy adhesive made by employing a manual cold press method. The type of bamboo used was the Bambusa Arundinacea variety that was greater than 3 years old. The bamboo laminate flexural strength was tested using the ASTM D 3043 Standard. The results of these tests revealed that the flexural strength of the laminated bamboo slats provided bending strengths of MOR and MOE values of 84.12 MPa and 18.04 GPa respectively. By using MOR and MOE values, and based on Bureau Classification of Indonesia (BKI), the shell thickness of 30 GT a fishing boat was calculated to be 25 -28 mm (bottom shell) and 19 -21 mm (side shell). These dimensions showed that the shell thickness can be reduced up to 33.3% when compared with teak (Tectona Grandis ) and the total volume of shell material to build a 30 GT of fishing boat, can be reduced by approximately 30%. The flexural strength of the bamboo slat laminate was shown to be 20% higher than 2nd class solid teak.

Research on Feasibility and Applicability of Delamination Localization Methods for Composite Laminated Beams

2014 ◽  
Vol 599-601 ◽  
pp. 92-95
Author(s):  
Hang Ma ◽  
Ping Lu ◽  
Tao Jiang ◽  
Sheng Feng Shi ◽  
Jian Bin Wei ◽  
...  
Keyword(s):  
Strain Energy ◽  
Damage Index ◽  
Energy Difference ◽  
Laminated Beams ◽  
Modal Strain Energy ◽  
Laminated Beam ◽  
Modal Strain Energy Method ◽  
Response Method ◽  
Strain Energy Ratio ◽  
Delamination Damage

The feasibility and applicability of delamination damages localization methods with various defined damage indexes for the damaged composite laminated beam were studied. The results indicate that, for the modal strain energy method, damage indexes defined by strain energy difference are more effective to locate the delamination damage than that of strain energy ratio. For energy response method, damage index defined by the second difference can effectively locate the delamination damage in the composite laminated beams.

scholarly journals EXPONENTIAL STABILITY OF LAMINATED BEAM WITH CONSTANT DELAY FEEDBACK

2021 ◽  
Vol 26 (4) ◽  
pp. 566-581
Author(s):  
Kassimu Mpungu ◽  
Tijani A. Apalara
Keyword(s):  
Wave Propagation ◽  
Exponential Stability ◽  
Propagation Speed ◽  
Transverse Displacement ◽  
Structural Damping ◽  
Constant Delay ◽  
Laminated Beams ◽  
Laminated Beam ◽  
Delay Term ◽  
Wave Propagation Speed

In this article, we consider a system of laminated beams with an internal constant delay term in the transverse displacement. We prove that the dissipation through structural damping at the interface is strong enough to exponentially stabilize the system under suitable assumptions on delay feedback and coefficients of wave propagation speed.

scholarly journals Strength Analysis and Stress-Strain Deformation Behavior of 3 mol% Y-TZP and 21 wt.% Al2O3-3 mol% Y-TZP

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3903
Author(s):  
Liliya Vladislavova ◽  
Tomasz Smolorz ◽  
Nina Orlovskaya ◽  
Mykola Lugovy ◽  
Michael J. Reece ◽  
...  
Keyword(s):  
Elastic Deformation ◽  
Deformation Behavior ◽  
Ceramic Composite ◽  
Bending Strength ◽  
Domain Switching ◽  
Small Deviation ◽  
Strength Analysis ◽  
Stress Strain ◽  
Linear Elastic ◽  
Four Point Bending

The mechanical behavior of 3 mol% Y2O3-ZrO2 ceramic and 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 ceramic composite with submicron grain size was studied. Mechanical properties, such as hardness, Young’s modulus, four-point bending strength, and fracture toughness of both materials were measured. Linear stress-strain deformation behavior of both 3 mol% Y2O3-ZrO2 and 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 was observed in flexure, both at room temperature and at 400 °C. A small deviation from linear elastic deformation was detected in 21 wt.% Al2O3-3 mol% Y2O3-ZrO2 ceramic composite when loaded above a stress of 1500 MPa. Therefore, it was concluded that only elastic deformation occurred at low stresses upon loading, which exclude the presence of domain switching in zirconia upon bending under the loading conditions of this study.

scholarly journals Glide analysis and bone strength tests indicate powered flight capabilities in hatchling pterosaurs

2017 ◽  
Author(s):  
Mark P Witton ◽  
Elizabeth Martin-Silverstone ◽  
Darren Naish
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Bone Strength ◽  
Bending Strength ◽  
Skeletal Development ◽  
Maximum Size ◽  
Strength Analysis ◽  
Life Stages ◽  
Strength Tests ◽  
Very High

Pterosaur embryos and ‘hatchling’ specimens show a surprising level of skeletal development including well-ossified skeletons and large wings. This has prompted interpretations of pterosaurs as being flight-capable from the earliest ontogenetic stages, contrasting them against the majority of other flying animals, living or extinct. Though popular, this hypothesis is not universally accepted. Some authors propose that pterosaurs only became flight capable once they reached 50% of maximum size, explaining a slowing of growth rate in later ontogeny as metabolic resources were diverted into an energy-demanding form of locomotion. We investigated these hypotheses through glide performance and wing bone strength analysis on hatchling-grade specimens of two pterosaurs, Pterodaustro guinazui and Sinopterus dongi. We found that hatchling pterosaurs were excellent gliders, but with a wing ecomorphology more comparable to powered fliers than obligate gliders. Bone strength analysis shows that hatchling pterosaur wing bones are structurally identical to those of larger pterosaurs and – because of their very low body masses – their bending strength relative to body weight is very high, comparable to or exceeding the greatest values estimated for larger, more mature pterosaurs. Hatchling pterosaurs are thus as mechanically adapted to powered flight stresses as other pterosaurs, if not moreso. Together with our glide tests, this result supports interpretations of hatchling pterosaurs as flight-capable. Size differences between pterosaur hatchlings and larger members of their species dictate differences in wing ecomorphology and flight capabilities at different life stages, which might have bearing on pterosaur ontogenetic niching.

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