Bending Properties
Typical load-deflection curves of OSL tested
in static bending were plotted at 3 different strand
lengths and are given in Figure 5. The bending
modulus of elasticity is the slope of a chord in the
linear region, which is the slope of a line drawn
from 10% to 40% of the maximum stress (BS EN
310, 1993). Specimens failed under tension at the
bottom surface.
The modified Hankinson formula, represented
by equation (4), is used to describe the
bending strength.
UBSOSL = UBSSW
1
20 ⋅sin(arctan(2 / ζ)) + cos(arctan(2 / ζ))
(4)
where UBSSW 95.45MPa interpolated to SG 0.7
(Dhonanon and Cheuwichitchan, 1980). Equation
(4) is plotted in Figure 6 with R2
of 0.89. UBSOSL
at 150 mm strand length was about 70% of UBSSW.
According to this equation, UBSOSL would approach
90% of the maximum value (UBSSW) for the strand
length of 360 mm (1 mm thickness).
BMOE at any given slenderness ratio, was
represented by