Hiroyuki Yamanouchi

Standardized mathematical expression for stress-strain relations of structural steel under monotonic and uniaxial tension loading

SummaryTension tests on 36 specimens of steel plates produced in Japan are carried out according to the testing method proposed by RILEM TC 83. The stress-strain curves obtained from the tests are mathematically expressed by determining the material constants included in a modified Menegotto-Pinto model. These results give standardized stress-strain relations with respect to SS41 and SM50A steels generally used in Japan as structural steels for building structures. These kinds of data are expected to be accumulated by many countries and should be then compared internationally to establish a more reasonable stress-strain relationship usable for structural analyses.

Statistical features of mechanical properties of current Japanese steels

As part of the work of RILEM T/C83-CUS, a statistical survey on mechanical properties of recent Japanese steels was performed on the basis of mill sheet data collected from six major mill makers of Japan. As a major result, wide scatter bands of yield point strength were found; this caused higher yield ratios of supplied steels than those based on the specified lower limits of yield strength and tensile strength. A high yield ratio is not preferable for ductility design of steel yield strength and tensile strength. A high yield ratio is not preferable for ductility design of steel structures. Thus, the upper limit of yield strength or yield ratio should be specified for such design use.