As-molded PDO without annealing showed 27.7 MPa yield strength, 10.4% yield strain
, elastic modulus of 593.5 MPa, and elongation at break of 215.7% tested under dry condition (namely without contact with PBS solution), as shown in Table 1.
Among these, the yielding state is defined as the state when the strain of the tensile reinforcement at the critical section reaches the yield strain
. The nominal flexural strength of the critical section is reached when the strain in the extreme compressed fibre reaches the ultimate strain , which is defined as the nominal ultimate limit state in this paper.
Keaveny, "Yield strain
behavior of trabecular bone," Journal of Biomechanics, vol.
With the increase in the model size, the decreasing speeds of the plastic yield stress and corresponding yield strain
The material testing obtained steel headed bar yield strains
of 3600 x [10.sup.-6].
Considering the flexural reinforcements, results were consistent because after recording the yield strain
, there was a little increase of the loading up to failure.
where [epsilon] and [sigma] are the strain and stress, respectively; [E.sub.s] is the elastic modulus; [[epsilon].sub.y] and [f.sub.y] are the yield strain
and yield stress, respectively; [e.sub.[mu]] is the ultimate strain.
As a benchmark, high-carbon steel offers a Young's modulus of about 200 GPa, a yield strain
of just under 1 percent, and a mass density of about 7.75 g/[cm.sup.3], for a maximum stored energy density in bending of about 0.4 kJ/kg.
Table 2 gives a comparison of the values of E, [R.sub.p02] (elastic limit at 0.2%), [[sigma].sub.y] (maximum yield stress), [[sigma].sub.y] (yield strain
), [[epsilon].sub.rupt] (strain at failure), [[sigma].sub.CD] (mean drawing stress or the stress plateau) and [DELTA][[epsilon].sub.CD] (extent of drawing in terms of % strain) for the HDPE exposed to considered environments.
The present study attempted to investigate the relationship between column parameters like slenderness ratio and thickness of FRP wrap and performance parameters like yield stress, axial yield strain
, lateral yield strain
, ultimate compressive stress, ultimate axial strain and ultimate lateral strain.
The applied strains for the peened strips are more than 1%, above the yield strain
of the strips.
Significant structural changes have probably occurred before that point, and due to the slightly different shape of stress-strain curves of weak specimens compared to stronger specimens, a yield strain
close to and even larger than the ultimate strain is sometimes found in weak specimens.