Ductility demand on structures designed based on NBCC 1985 base shear specification.

A statistical analysis based on three sets of earthquake records is performed to investigate the significance of peak ground acceleration to velocity ratio (a/v) on the displacement ductility demand of simple inelastic systems. The yield strength of the systems is specified from the base shear formula in the 1985 National Building Code of Canada (NBCC 1985) and that in NBCC 1980 respectively. A comparison of the statistical results between the two methods shows that the a/v ratio of ground motion has a significant effect on the displacement ductility demand and the base shear provisions in NBCC 1985 provide an effective way to incorporate the a/v ratio into design base shear specification.- from Authors