On the Design of High-Rise Buildings for Multihazard: Fundamental Differences between Wind and Earthquake Demand

摘要

In the past few decades, high-rise buildings have received a renewed interest in many city business locations, where land is scarce, as per their economics, sustainability, and other benefits. Taller and taller towers are being built everywhere in the world. However, the increased frequency of multihazard disasters makes it challenging to balance between a resilient and sustainable construction. Accordingly, it is essential to understand the behavior of such structures under multihazard loadings, in order to apply such knowledge to design. The results obtained from the dynamic analysis of two different high-rise buildings (54-story and 76-story buildings) investigated in the current study indicate that earthquake loads excite higher modes that produce lower interstory drift, compared to wind loads, but higher accelerations that occur for a shorter time. Wind-induced accelerations may have comfort and serviceability concerns, while excessive interstory drifts can cause security issues. The results also show that high-rise and slender buildings designed for wind may be safe under moderate earthquake loads, regarding the main force resisting system. Nevertheless, nonstructural components may present a significant percentage of loss exposure of buildings to earthquakes due to higher floor acceleration. Consequently, appropriate damping/control techniques for tall buildings are recommended for mitigation under multihazard.