According to this standard A m is defined as 2.5 A o , which is an average
condition found in response spectra in general. It is also defined that T c = 0.5 sec for
Hard Soil, T c = 0.6 sec for Medium Soil and T c = 1.0 sec for Soft Soil, all of which
being approximate values.
Based on these conditions for each seismic zone, the
values of A o , A m and A r of the response spectra of the Design Earthquake are as
listed in Table 3.