Bending Strength of Magnesium Oxide Board

2021 ◽  
Vol 879 ◽  
pp. 169-178
Author(s):  
Teck Jung Chai ◽  
Tan Cher Siang ◽  
Tang Hing Kwong ◽  
Koh Heng Boon

Magnesium Oxide (MgO) board has been widely used in prefabricated lightweight steelframe wall systems and as the floor board covering component. It is a non-insulating sheathingboard product which consists of sustainable materials with the characteristics of fire resistance,weather-ability, strength, resistance to mold and mildew. Although MgO board has recentlyworldwide used in façade construction but the research data related to the laboratory work such asthe bending strength is still limited. The previous studies on the bending strength of MgO board arebased on various standards such as ASTM, JC688 and British Standard subjected to the productscharacteristics and patterns. Therefore, the bending strength values obtained were inconsistent andnot convincing. Thus, this paper aims to examine the bending strength of MgO board with threedifference thicknesses (6mm, 9 mm and 12 mm) based on BS EN 310:1993 subjected to threepoints bending test. The failure modes during three points bending test was observed and theexperimental results obtained were compared with the theoretical values and others relevantstandards. A total of thirty six specimens with twelve specimens for each thickness in two groupdirections namely longitudinal (length) and transverse (width) direction were tested. The specimenswere prepared based on BS EN 326-1:1994 and BS EN 325:2012. The maximum flexure load of thespecimens was recorded and arithmetic mean bending strength for each thickness was presented.The experimental results showed the tested MgO board was not achieved minimum bendingstrength for load bearing used. It is recommended to be used in non-load bearing façade claddingconstruction.

2019 ◽  
Vol 89 (19-20) ◽  
pp. 4046-4059 ◽  
Author(s):  
Hongjian Zhang ◽  
Junhua Guo ◽  
Weidong Wen ◽  
Haitao Cui ◽  
Shu He

In this paper, a kind of T-shaped hook-connected structure, which consists of a T-shaped plate made of two-and-a-half-dimensional woven composites and a groove structure made of T300/BMP316 laminated composites, was designed as the simulator specimen of the connection structure between the vane and the case in an aero-engine. As the bending strength and tensile strength are important mechanical properties, bending tests and tensile tests, respectively, of the T-shaped hook-connected structure were conducted to study the mechanical properties and failure modes under bending and tensile loads on web. Experimental results showed that the initial damages both occur at the root-edge, and then the damages extend to the root-middle during the bending test or extend perpendicular to the root-edge to the margin of the flange during the tensile test. Then, a strength prediction method based on the progressive damage theory was developed to simulate the mechanical properties and damage processes of the T-shaped hook-connected structure under bending and tensile loads, respectively. Compared with experimental results, the maximum error is less than 10%, and the damage modes are similar.


2019 ◽  
Vol 4 (1) ◽  
pp. 41-53
Author(s):  
Nor Jihan Abd Malek ◽  
◽  
Sadiq Azizi Othman ◽  

Timber is one of the oldest materials used as main structural element prior concrete and steel which have greater ability to sustain load. The greater demand for timber as construction materials, the wood engineering introduced a new timber type called Engineered Wood Product (EWP). The crucial problem in the timber structure which focuses on the structural timber connection. The load-carrying capacity of the timber connection and the failure modes can be determined according to the European Yield Model (EYM). Three-point bending test was used to determine yield moment of the fastener, My, bolt bending strength, Fyb and average R-value for three selected different bolt diameters which are 12, 16 and 20 mm. The results were obtained for comparing between three bolt diameters with F2%, F5% and Fmax respectively. The F2% for 12, 16 and 20 mm yield moment of the fastener, My was obtained 596.4, 1631.5 and 4650 kNmm accordingly while for bolt bending strength, Fyb was 2.1, 2.4 and 3.5 kN correspondingly. The F5% for 12, 16 and 20 mm yield moment of the fastener, My was obtained 631.1, 1668.3 and 4895.6 kNmm accordingly while for bolt bending strength, Fyb was 2.2, 2.4 and 3.7 kN correspondingly. The Fmax for 12, 16 and 20 mm yield moment of the fastener, My was obtained 828.2, 2290.8 and 6545.4 kNmm accordingly while for bolt bending strength, Fyb was 2.9, 3.4 and 4.9 kN correspondingly. The average R-value for 12, 16 and 20 mm bolt diameter was 0.50214, 0.42768 and 0.42038 individually. In conclusion, the percentage difference for F2% bolt bending strength, Fyb between 12 and 16 mm has raised about 14% whereas 16 and 20 mm has shown 46% increased.


Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2602
Author(s):  
Huaqiao Wang ◽  
Jihong Chen ◽  
Zhichao Fan ◽  
Jun Xiao ◽  
Xianfeng Wang

Automated fiber placement (AFP) has been widely used as an advanced manufacturing technology for large and complex composite parts and the trajectory planning of the laying path is the primary task of AFP technology. Proposed in this paper is an experimental study on the effect of several different path planning placements on the mechanical behavior of laminated materials. The prepreg selected for the experiment was high-strength toughened epoxy resin T300 carbon fiber prepreg UH3033-150. The composite laminates with variable angles were prepared by an eight-tow seven-axis linkage laying machine. After the curing process, the composite laminates were conducted by tensile and bending test separately. The test results show that there exists an optimal planning path among these for which the tensile strength of the laminated specimens decreases slightly by only 3.889%, while the bending strength increases greatly by 16.68%. It can be found that for the specific planning path placement, the bending strength of the composite laminates is significantly improved regardless of the little difference in tensile strength, which shows the importance of path planning and this may be used as a guideline for future AFP process.


2019 ◽  
Vol 28 ◽  
pp. 096369351987741
Author(s):  
Gyula Szabó ◽  
Károly Váradi

The aim of this study is to investigate the global buckling of a relatively long composite cord–rubber tube subjected to axial compression and its cross-sectional instability due to bending by a macromechanical nonlinear finite element (FE) model (nonlinear buckling analysis). Composite reinforcement layers are modelled as transversely isotropic ones, while elastomer liners are described by a hyperelastic material model that assumes incompressibility. Force–displacement, equivalent strain, equivalent stress results along with oblateness and curvature results for the complete process have been presented. It is justified that bending leads to ovalization of the cross section and results in a loss of the load-carrying capacity of the tube. Strain states in reinforcement layers have been presented, which imply that the probable failure modes of the reinforcement layers are both delamination and yarn-matrix debonding. There is a significant increase in strains due to cross-sectional instability, which proves that the effect of cross-sectional instability on material behaviour of the tube is crucial. A parametric analysis has been performed to investigate the effect of the member slenderness ratio on cross-sectional instability of the composite tube. It shows that Brazier force is inversely proportional to the slenderness ratio. It further shows that higher oblateness parameters occur in case of a lower slenderness ratio and that cross-sectional instability takes place at a lower dimensionless displacement in case of a lower slenderness ratio. FE results have been validated by a compression/bending test experiment conducted on a tensile test machine.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3030
Author(s):  
Łukasz Smakosz ◽  
Ireneusz Kreja ◽  
Zbigniew Pozorski

Edgewise compression response of a composite structural insulated panel (CSIP) with magnesium oxide board facings was investigated. The discussed CSIP is a novel multifunctional sandwich panel introduced to the housing industry as a part of the wall, floor, and roof assemblies. The study aims to propose a computational tool for reliable prediction of failure modes of CSIPs subjected to concentric and eccentric axial loads. An advanced numerical model was proposed that includes geometrical and material nonlinearity as well as incorporates the material bimodularity effect to achieve accurate and versatile failure mode prediction capability. Laboratory tests on small-scale CSIP samples of three different slenderness ratios and full-scale panels loaded with three different eccentricity values were carried out, and the test data were compared with numerical results for validation. The finite element (FE) model successfully captured CSIP’s inelastic response in uniaxial compression and when flexural action was introduced by eccentric loads or buckling and predicted all failure modes correctly. The comprehensive validation showed that the proposed approach could be considered a robust and versatile aid in CSIP design.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Fuminobu Ozaki ◽  
Takumi Umemura

PurposeIn this study, the bending strength, flexural buckling strength and collapse temperature of small steel specimens with rectangular cross-sections were examined by steady and transient state tests with various heating and deformation rates.Design/methodology/approachThe engineering stress and strain relationships for Japan industrial standard (JIS) SN400 B mild steels at elevated temperatures were obtained by coupon tests under three strain rates. A bending test using a simple supported small beam specimen was conducted to examine the effects of the deformation rates on the centre deflection under steady-state conditions and the heating rates under transient state conditions. Flexural buckling tests using the same cross-section specimen as that used in the bending test were conducted under steady-state and transient-state conditions.FindingsIt was clarified that the bending strength and collapse temperature are evaluated by the full plastic moment using the effective strength when the strain is equal to 0.01 or 0.02 under fast strain rates (0.03 and 0.07 min–1). In contrast, the flexural buckling strength and collapse temperature are approximately evaluated by the buckling strength using the 0.002 offset yield strength under a slow strain rate (0.003 min–1).Originality/valueRegarding both bending and flexural buckling strengths and collapse temperatures of steel members subjected to fire, the relationships among effects of steel strain rate for coupon test results, heating and deformation rates for the heated steel members were minutely investigated by the steady and transient-state tests at elevated temperatures.


2017 ◽  
Vol 2017 ◽  
pp. 1-20
Author(s):  
Ulf Arne Girhammar ◽  
Bo Källsner

The authors present an experimental and analytical study of slotted-in connections for joining walls in the Masonite flexible building (MFB) system. These connections are used for splicing wall elements and for tying down uplifting forces and resisting horizontal shear forces in stabilizing walls. The connection plates are inserted in a perimeter slot in the PlyBoard™ panel (a composite laminated wood panel) and fixed mechanically with screw fasteners. The load-bearing capacity of the slotted-in connection is determined experimentally and derived analytically for different failure modes. The test results show ductile postpeak load-slip characteristics, indicating that a plastic design method can be applied to calculate the horizontal load-bearing capacity of this type of shear walls.


2005 ◽  
Vol 297-300 ◽  
pp. 2046-2051 ◽  
Author(s):  
Jin Wook Kim ◽  
B.W. Park ◽  
Seok Hwan Ahn ◽  
Ki Woo Nam

This paper reports for signal characteristics of before-and-after healing treatment SiC ceramics with crack healing ability. The elastic wave signals generated during the compress load by a Vickers indenter on the brittle materials were recorded in real time, and the waveforms of the individual signals were examined and classified based on their spectral characteristics. The compress loads were applied with the range from 9.8N to 294N. In a bulk SiC specimen, the AE signals occurred only when the load was compressive loading and unloading. But, in the after crack healing specimen of 294N only, even though the external compressive load was stopped and kept on holding constant load states, the AE signals occurred irregularly and continuously. The results of the WT and frequency analysis showed that these existed as the property of frequency in the limited range between 100kHz and about 200kHz. Three-point bending test was performed for the cracked and healed SiC specimens. Consequently the bending strength of the crack healed specimens was recovered completely, but most of the samples with the crack healed showed that the properties of the dominant frequency were comparatively lower than that of the bulk SiC samples. The classification of the wave signals can be used to develop algorithms for autonomous health monitoring systems of brittle material structures.


2012 ◽  
Vol 184-185 ◽  
pp. 1163-1166
Author(s):  
Xi An Xie ◽  
Gao Feng Quan

Through the four-point bending test of lath-shaped heat treated AZ31 magnesium alloy, the bending properties and damage characteristics were explored. The results show that the optimal bending strength of the magnesium alloy were 355.1MPa and 259.2MPa for extruded and cast samples, respectively, after corresponding heat treatment with 350°C, 90min and 400°C, 30min. The initial cracks both occurred at the loading point after applied load exceeded the yield limit of AZ31 magnesium alloy. Surface bump, cracks and other damage morphology accompanied by a large number of twinning organizations were found on the surface of the samples.


Author(s):  
Kobra Tajaddodi Talab ◽  
Mohd. Nordin Ibrahim ◽  
Sergey Spotar ◽  
Rosnita A. Talib ◽  
Kharidah Muhammad

Abstract Glass transition temperatures (Tg) of MR219 rice variety were measured by differential scanning calorimeter (DSC). State diagram was developed and used to evaluate drying process in this study. Glass transition temperatures range of 9.65- 61.79°C were observed for gains with moisture content of 26.8 – 7.4% (w.b.). For mechanical properties and milling test, statistical analysis was performed by using a two factor experiment in completely randomized design (CRD). Two selected factors were drying temperatures at 5 levels (40, 45, 50, 55, and 60°C) and final moisture content (FMC) at 4 levels (10-10.5, 11-11.5, 12-12.5 and 13-13.5%). Three–point bending test was applied to measure the mechanical properties of rice kernel. Generally, bending strength, apparent modulus of elasticity and fracture energy of brown rice kernel increased with decreasing the grain moisture content. Maximum bending strength was 35.69 and 33.64 MPa for 55, and 60°C, respectively. All samples that were dried at 55 and 60°C experienced to go through the glass transition line after reaching their temperature to the room temperature at the end of drying process. The effect of drying temperature, paddy FMC and their interactions on whole kernel percentage (WKP) and mechanical properties were significant (α = 0.05). An inverse relationship was observed between WKP and the percentage of strong kernels for all treatments.


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