scholarly journals Estimating Mechanical Properties of Wood in Existing Structures—Selected Aspects

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1941
Author(s):  
Tomasz Nowak ◽  
Filip Patalas ◽  
Anna Karolak
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Experimental Tests ◽  
Visual Assessment ◽  
Modulus Of Rupture ◽  
Testing Methods ◽  
Existing Structures ◽  
Drilling Method ◽  
Resistance Drilling ◽  
Non Destructive

The paper presents and discusses selected methods of wood classification and the evaluation of its mechanical properties. Attention was mainly paid to methods that may be particularly useful for examining existing elements and structures. The possibility of estimating the modulus of rupture—MOR and modulus of elasticity—MOE based on the non- destructive (NDT), semi-destructive (SDT), and destructive tests (DT) were considered. Known international, European, and American standards and research approaches were indicated. The selected testing methods and their interpretation were presented. These were, among others, the method of visual assessment, the resistance drilling method, methods of determining the dynamic modulus of elasticity, and procedures for testing small clear specimens. Moreover, some of our own research results from the conducted experimental tests were presented and discussed. In the destructive tests, both large elements and small clear specimens were examined. The results obtained from individual methods were compared and some conclusions were presented. The summary discusses the fundamental difficulties and limitations in applying the presented procedures and interpretations.

Pengaruh Tekanan dan Penggunaan Conplast terhadap Sifat Mekanik Eternit dari Abu Cangkang Sawit

2016 ◽  
Vol 8 (15) ◽  
pp. 47-54
Author(s):  
Haspiadi Haspiadi
Keyword(s):  
Mechanical Properties ◽  
Oil Palm ◽  
Modulus Of Elasticity ◽  
Modulus Of Rupture ◽  
Palm Shell ◽  
Oil Palm Shell ◽  
Density Values ◽  
Test Result

The purpose of this research is to know the influence of pressure and use of conplast against mechanical properties which are a Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of plasterboard. The study is done because still low quality of plasterboard made from a mixture of ashes of oil-palm shell especially of the mechanical properties compared to the controls. The method of this reserach used variation of printed pressure and the addition of conplast. Test result is obtained that the highest value of Modulus of Elasticity (MOE) 90875.94 Kg/cm2, Modulus of Rupture (MOR) 61.16 Kg/cm2 and density values in generally good printed at the pressure 60 g/cm3 and the addition of conplast 25% as well as the composition of the ash of palm shell oil 40%: limestone 40%: cement 15%: fiber 5% and 300 mL of water. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh tekanan dan penggunaan conplast terhadap sifat mekanik yaitu kuat lentur dan keteguhan patah eternit berbahan dasar abu cangkang sawit. Penelitian ini dilakukan karena masi rendahnya mutu eternit berbahan campuran abu cangkang sawit dari bolier khususnya sifat mekanik dibandingkan dengan kontrol. Metode penelitian yang digunakan adalah dengan variasi tekanan cetak dan penambahan conplast. Hasil uji diperoleh bahwa kuat lentur tertinggi sebesar 90875,94 Kg/cm2 dan keteguhan patah sebesar 61,16 Kg/cm2, yang dicetak pada tekanan 60 g/cm3 dan penambahan conplast 25% dengan komposisi  abu cangkang sawit 40 %: kapur 40 % : semen 15 %: serat 5 % dan air 300 mL.Kata Kunci :  Abu cangkang sawit, conplast, kuat lentur, keteguhan patah.

Influence of Moisture Content in some Mechanical Properties of Two Brazilian Tropical Wood Species

2014 ◽  
Vol 1025-1026 ◽  
pp. 42-45 ◽  
Author(s):  
Luiz A. Melgaço N. Branco ◽  
Eduardo Chahud ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr ◽  
Rosane A.G. Battistelle ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Moisture Content ◽  
Analysis Of Variance ◽  
Wood Species ◽  
Modulus Of Elasticity ◽  
Modulus Of Rupture ◽  
Tropical Wood ◽  
Fiber Saturation ◽  
Brazilian Standard

This study aimed, with the aid of analysis of variance (ANOVA), to investigate and quantify the influence of moisture ranging between 12% and over 30% (fiber saturation) on the mechanical properties: strength and modulus of elasticity in compression and in tension parallel to grain; modulus of rupture and modulus of elasticity in static bending; shear strength parallel to grain considering wood species Ipê (Tabebuia sp) and Angelim Araroba (Vataireopsis araroba). Tests were performed according to the assumptions and calculating methods Brazilian standard ABNT NBR 7190, Anexx B, totalizing 400 tests. Results of ANOVA revealed a significant reduction (16% on average) for mechanical properties wood due to the increase in moisture content from 12% to over 30% (fiber saturation). The same behavior also occurred when assembly containing the two species was considered.

scholarly journals Sixteen properties of Eucalyptus Tereticornis wood for structural uses

2020 ◽  
Vol 36 (2) ◽  
Author(s):  
Marta Cristina de Jesus Albuquerque Nogueira ◽  
Victor Almeida de Araujo ◽  
Juliano Souza Vasconcelos ◽  
André Luis Christoforo ◽  
Francisco Antonio Rocco Lahr
Keyword(s):  
Mechanical Properties ◽  
Decision Making ◽  
Shear Stress ◽  
Modulus Of Elasticity ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Eucalyptus Tereticornis ◽  
Moisture Contents ◽  
Through Diffusion ◽  
Standard Documents

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.

scholarly journals Mechanical Properties of Commercial Particleboard from Rubberwood (Hevea Brasiliensis) and Recycle Mix-Tropical Wood with Different Board Density

2021 ◽  
Vol 3 (1) ◽  
pp. 41-44
Author(s):  
Nur Wafa Amalina Amali ◽  
Nor Yuziah Mohd Yunus ◽  
Wan Mohd Nazri Wan Abdul Rahman
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Hevea Brasiliensis ◽  
Urea Formaldehyde ◽  
Wood Particle ◽  
Modulus Of Rupture ◽  
Internal Bonding ◽  
Board Density ◽  
Tropical Wood ◽  
Minimum Requirements

In this study, mechanical properties of commercially manufactured hybrid particleboard from mix-tropical wood and rubberwood with four different densities at 25mm thickness have been investigated. The particleboard sample cutting and testing was in accordance to EN312:2013. The density of particleboard is identified with interval of 10kg/m3 for different densities which include 660kg/m3, 670kg/m3, 680kg/m3 and 690kg/m3. Particleboards were made with the ratio of 40:60 for mix-tropical wood particle and rubberwood particle respectively. The particleboards were prepared with urea formaldehyde (UF) with E1 formulation with addition of wax and hardener.  Increment of 10kg/m3 density for each particleboard led to increase in internal bonding (IB), bending testing include modulus of rupture (MOR) and modulus of elasticity (MOE), surface soundness (SS) and screw edge (SE) withdrawal. It was found that with board increment of 10kg/m3, the improvement was not statically significant except that for MOR. All panels met the minimum requirements of standard.

scholarly journals Reliability assessment of existing bridge constructions based on results of non-destructive testing

2018 ◽  
Vol 199 ◽  
pp. 06001 ◽  
Author(s):  
Stefan Küttenbaum ◽  
Alexander Taffe ◽  
Thomas Braml ◽  
Stefan Maack
Keyword(s):  
Measurement Data ◽  
Basic Research ◽  
Relevant Information ◽  
Structural Safety ◽  
Non Destructive Testing ◽  
Testing Methods ◽  
Destructive Testing ◽  
Uncertainty In Measurement ◽  
Existing Structures ◽  
Non Destructive

The non-destructive testing methods available for civil engineering (NDT-CE) enable the measurements of quantitative parameters, which realistically describe the characteristics of existing buildings. In the past, methods for quality evaluation and concepts for validation expanded into NDT-CE to improve the objectivity of measured data. Thereby, a metrological foundation was developed to collect statistically sound and structurally relevant information about the inner construction of structures without destructive interventions. More recently, the demand for recalculations of structural safety was identified. This paper summarizes a basic research study on structural analyses of bridges in combination with NDT. The aim is to use measurement data of nondestructive testing methods as stochastic quantities in static calculations. Therefore, a methodical interface between the guide to the expression of uncertainty in measurement and probabilistic approximation procedures (e.g. FORM) has been proven to be suitable. The motivation is to relate the scientific approach of the structural analysis with real information coming from existing structures and not with those found in the literature. A case study about the probabilistic bending proof of a reinforced concrete bridge with statistically verified data from ultrasonic measurements shows that the measuring results fulfil the requirements concerning precision, trueness, objectivity and reliability.

Design and Property Analysis of the Metal Mesh Reinforced LVL

2010 ◽  
Vol 113-116 ◽  
pp. 2145-2149
Author(s):  
Ying Cheng Hu ◽  
Jin Li ◽  
Fang Chao Cheng ◽  
Xu Jie Zhang
Keyword(s):  
Mechanical Properties ◽  
Modulus Of Elasticity ◽  
Modulus Of Rupture ◽  
Bending Test ◽  
Metal Mesh ◽  
Fast Growing ◽  
Laminated Veneer Lumber ◽  
Property Analysis ◽  
Wood Grain

This study mainly analyzed the factors that affected the mechanical properties of laminated veneer lumber（LVL）. To increase the mechanical properties, metal mesh was inserted into LVL that made of fast-growing timber. Effects of different factors were evaluated on the mechanical properties of LVL, several enhancement modes of metal mesh were designed to reinforce the LVL. Then, the mechanical properties (modulus of rupture and modulus of elasticity) of the LVL specimens were measured by static bending test. The results of different enhancement modes were analyzed and compared to investigate the effects of different factors. The position of metal mesh and the mesh number of metal mesh make significant effects on the MOE; the type of metal mesh and the angle of metal mesh-wood grain do not have any obvious effects on the MOE. The type of metal mesh and the position of metal mesh make significant effects on the MOR; the mesh number of metal mesh and the angle of metal mesh-wood grain do not have any obvious effects on the MOR.

The Effect of Impregnation Process on the Performance of Veneer Composite Plank

2011 ◽  
Vol 239-242 ◽  
pp. 2411-2414
Author(s):  
Xing Zhen ◽  
Jiu Yin Pang ◽  
Shi Cheng Zhang ◽  
Ya Zhe Jiang
Keyword(s):  
Mechanical Properties ◽  
Drug Absorption ◽  
Modulus Of Elasticity ◽  
Absorption Rate ◽  
Normal Pressure ◽  
Modulus Of Rupture ◽  
Impregnation Process ◽  
Impregnation Time ◽  
Peak Value

This study focuses on the effect of impregnation process on the main mechanical properties in the production of veneer composite plank. The results showed that:①Under the normal pressure and temperature the drug absorption of impregnated veneer shall extend the volume with the growth in impregnation time, but growing faster early, the later change slowly. In the impregnation process under pressure, its absorption rate and speed are greatly increased. ②The Modulus of rupture (MOR) and modulus of elasticity (MOE) of veneer composite plank are gradually increased with the drug absorption increased, but after reached a certain peak value they gradually decrease, and the variation of MOE is smaller than MOR.

scholarly journals Mechanical properties of sandwich panels constructed from polystyrene/cement mixed cores and thin cement sheet facings

2015 ◽  
Vol 19 (4) ◽  
pp. 456-481 ◽  
Author(s):  
Hamid Reza Tabatabaiefar ◽  
Bita Mansoury ◽  
Mohammad Javad Khadivi Zand ◽  
Daniel Potter
Keyword(s):  
Mechanical Properties ◽  
Ultimate Strength ◽  
Mechanical Behaviour ◽  
Modulus Of Elasticity ◽  
Sandwich Panel ◽  
Sandwich Panels ◽  
Experimental Tests ◽  
Practical Applications ◽  
Building Components ◽  
Cement Board

Sandwich panels are made of two materials that are relatively weak in their separated state, but are improved when they are constructed together in a sandwich panel. Sandwich panels can be used for almost any section of a building including roofs, walls and floors. These building components are regularly required to provide insulation properties, weatherproofing properties and durability in addition to providing structural load bearing characteristics. Polystyrene/cement mixed cores and thin cement sheet facings sandwich panels are Australian products made of cement-polystyrene beaded mixture encapsulated between two thick cement board sheets. The structural properties of sandwich panels constructed of polystyrene/cement cores and thin cement sheet facings are relatively unknown. Therefore, in this study, to understand the mechanical behaviour and properties of those sandwich panels, a series of experimental tests have been performed and the outcomes have been explained and discussed. Based on the results of this study, values for modulus of elasticity and ultimate strength of the sandwich panels in dry and saturated conditions have been determined and proposed for practical applications.

scholarly journals Effects of thermo-hydro-mechanical treatments on various physical and mechanical properties of poplar (Populus) wood

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 9596-9610
Author(s):  
Yali Shao ◽  
Lili Li ◽  
Zhangjing Chen ◽  
Sunguo Wang ◽  
Ximing Wang
Keyword(s):  
Mechanical Properties ◽  
Thermal Treatment ◽  
Modulus Of Elasticity ◽  
Mechanical Treatment ◽  
Elasticity Modulus ◽  
Physical And Mechanical Properties ◽  
Modulus Of Rupture ◽  
Compression Rate ◽  
Thickness Swelling ◽  
Maximum Thickness

Poplar (Populus) wood was subjected in this work to thermo-hydro-mechanical treatment. The influence of the treatment parameters on the physical and mechanical properties were investigated. The wood samples were densified under three compression ratios (0%, 30%, and 50%), and thermally treated at three temperatures (180 °C, 200 °C, and 220 °C), at three thermal treatment durations (3 h, 4 h, and 5 h). The density, modulus of elasticity, modulus of rupture, radial hardness, and thickness swelling were measured. The results showed that the densities of the samples increased by 36.6% to 49.7%. As the compression rate increased, the temperature, duration, modulus of elasticity, modulus of rupture, and hardness increased. However, the dimensions of the densified samples were less stable. Compared to the densified samples, the maximum thickness swelling could be reduced by 74% (from 29.7% to 7.8%) when subjected to a thermal treatment at 220 °C for 3 h.

scholarly journals Weathering performance of mulberry wood with UV varnish applied and its mechanical properties

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 6791-6798
Author(s):  
Vedat Çavuş
Keyword(s):  
Mechanical Properties ◽  
Adhesion Strength ◽  
Modulus Of Elasticity ◽  
Morus Alba ◽  
Modulus Of Rupture ◽  
Pendulum Hardness ◽  
Yellow Color ◽  
Parallel Direction ◽  
Uv Lamps

Mulberry wood is used in carpentry, fences, turnery, and garden architecture. In this study, various mechanical properties (modulus of rupture, modulus of elasticity, Janka hardness, and screw holding resistance) of mulberry (Morus alba) wood and its weathering performance after applying 3- and 5-layer UV system parquet varnishes with different surface applications were investigated. The varnished materials were aged using UV lamps for 252 h and 504 h, and the aged specimens were compared with non-aged specimens. The results of the variance analyses found that all tests were significant. According to the results, it was found that while the yellow color (b*) tone value, lightness, and glossiness (perpendicular (⊥) and parallel (║) direction at 20°, 60°, and 85° angles) values decreased for both varnish applications, the pendulum hardness value increased. The adhesion strength (pull-off) test (MPa) to the surface first decreased and then increased.

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