Challenges for the Next Generation of Seismic Codes - Earthquake Engineering for Structural Design - page 479

Distance (km)
Fault normal
Directivity
Fault parallel
Figure 10. 3 Distribution of maximum story drifts for thrust ground motions:
(after Park et al, 2004)
The particularity of the frame response to near-source ground motions is again
prevalent. Contrary to the far-source earthquake (as are the requirements of
common codes), the distribution of the demands over the height of the structure is
highly non-uniform for the near-source records and depends on the designed
ductility of the structure. For moderate designed ductility (rigid structure), the
maximum ductility demands are concentrated at the top stories of the structure.