Modulus of rupture, MOR -

Sugar maple was reacted with propylene and butylene oxide (Rowell etal., 1982). The modulus of elasticity (MOE) and modulus of rupture (MOR), fibre stress at proportional limit, and maximum crushing strength all exhibited a reduction, compared to unmodified samples. Nilsson and Rowell (1983) reacted ponderosa pine with butylene oxide and exposed the wood in an unsterile soil decay test. At low WPGs, severe surface decay due to soft rot and tunnelling bacteria was observed. Such attack was reduced at 15 % WPG,... 

Gerhards (57) reviewed the results of 12 separate studies on strength properties of fire-retardant-treated wood conducted at the FPL and other laboratories. He concluded that modulus of rupture (MOR) is consistently lower and modulus of elasticity (MOE) and work to maximum load are generally lower for fire-retardant-treated wood than for untreated wood if fire-retardant treatment is followed by kiln drying. The effect may be less or negligible if the fire-retardant-treated wood is air dried instead of kiln dried. The most significant loss was in work to maximum load, a measure of shock resistance or brashness, which averaged 34 percent reduction. 

The values of the axial and tangential modulus of rupture (MOR) at high temperature, which impact the filter s thermal durability, are summarized in Table 8. Again, the EX-80 filter excels in this property relative to other filter compositions. Similarly, the axial" E-modulus data in Table 9 show that the EX-80 filter has similar stiffness to that of the EX-47 and EX-54 filters, notably at or below 600°C (representative of the filter s peripheral temperature during regeneration). 

After conditioning the boards at 25 C and RH 65% for one month, bending specimens measuring 50 mm in width and 280 mm in length were cut. The three-point bending test was conducted according to the JIS (Japanese Industrial Standard) A 5908, and modulus of rupture (MOR) of each type of board were determined. 

Board properties determined were modulus of rupture (MOR), modulus of elasticity (MOE), swelling and water absorption after 24-hour water soak. Testing was done according to Japanese Industrial Standard (JIS) 5906 except that 130x 25 mm bending specimens were tested over a 50 mm span. 

It is obvious that flexure tests should be directly proportional to specimen width. Numerous tests on both types of machines have confirmed this. The modulus of rupture (MOR) formula predicts that flexural strength should be inversely proportional to the span. Combining these relationships we can calculate that the test on the 12 by 16 specimen should be 12/10 X 10/14 = 0.857 times the strength of the 10 by 12 specimen. This is reasonably close to the slope of 0.8 found for the correlation equation. Gypsum wallboard is not a homogeneous material as is assumed in the calculation of MOR. 

Reduction of furfural leads to furfuryl alcohol 63 which can be easily transformed into resins, thus replacing phenol formaldehyde resins (Scheme 21) [115]. A recent apphcation concerns impregnation of wood (furfurylated wood). For instance, high retention of grafted or polymerized furfuryl alcohol improves a variety of properties such as an increased hardness, resistance to microbial decay and insect attack, as well as resistance to chemical degradaticai. Modulus of rupture (MOR), elasticity (MOE), and the dimensional stabihty are also significantly increased. 

Figure 1. Improvement factor ratio of modulus of rupture (MOR) (bending strength) values of wood treated with Butvar B98 and untreated wood for deteriorated Douglas-fir at various levels of residual bending strength (degrees...

The maximum tensile stress in the surface of the beam when it breaks is called the modulus of rupture (MOR), o,. For an elastic beam it is related to the maximum moment in the beam, M... 

The modulus of rupture (MOR), modulus of elasticity (MOE) in bending, and tensile strength (TS) parallel to the board surface are shown in Table 7.16 for fiberboards made from control and acetylated kenaf fiber. Acetylation results in a small decrease in MOR, but about... 

Modulus of Rupture (MOR), Modulus of Elasticity (MOE), and Tensile Strength (TS) Parallel to the Board Surface of Fiberboards Made from Control or Acetylated Kenaf Fiber and 8% Phenolic Resin... 

Modulus of rupture, MOR. was obtained on polished samples by four point bend tests (4 X 20 mm) with 1 mmmin deformation rate using Instron equipment. The elastic modulus, E, was measured at room temperature, by the acoustic resonance method using a self-assembled apparatus and, at high temperature, from the stress-strain curve obtained in the four point bend tests. 

Figure 10. Evolution of the flexural strength, modulus of rupture (MOR), of the ceramic samples pyrolized at 1000°C, 1 h, with the Al/Si ratio.

Table II. four-point modulus of rupture (MOR) of aluminum phosphate-coated BAS parts.

Table 3 summarizes the Analysis of Variance (ANOVA) results for the effects of treatment (untreated and treated), veneer layer and adhesive spread amount. The results show that there were highly significant interactions between these three variables in terms of Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) of OPS plywood. However, it was also observed that the effect of adhesive spread amount was only moderately significant on the bond integrity of OPS plywood in terms both dry and wet shear strengths. 

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