Major seismic events around the world have displayed the close relationship between lateral displacements, and structural and non-structural damage in buildings. Whilst most seismic design standards are presently force-based, the majority have established limits on lateral drift.
This paper documents a study of the stiffness characteristics nominated in several seismic codes, focusing in particular on the requirement to control lateral drift. A method for evaluating and comparing the control of inter-storey displacements is proposed, and an evaluation of seismic codes is undertaken, including: Australia (1), Chile (2), Colombia (3), Europe (4), New Zealand (5), Panama (6), Peru (7), Turkey (8) and the USA (9, 10 & 11).
The results of this study show that the Chilean code is the most stringent in controlling lateral displacements. In the short period region (up to 0.13 sec) the Colombian, Peruvian and New Zealand codes are among the most stringent, while for periods in between 0.13 sec to 2.85 sec the Eurocode 8 is second only to the Chilean. For longer periods, the Colombian (2.85 sec), Peruvian (3.70 sec), Panamanian (4.00 sec), Turkish (4.75 sec), American (4.90 sec and 5.30 sec), New Zealand (7.70 sec), and Australian (9.65 sec) seismic standards, respectively, are all more stringent than the European normative. Among the least rigorous standards is the Panamanian for periods up to 2.65 sec, with the Australian standard the least stringent for periods up to 9.65 seconds. A direct comparison of the major seismic codes of the USA and Europe shows that the latter are more rigorous up to a period of 4.9 sec. The opposite applies thereafter, with American standards more stringent for longer period structures.