DESIGN CRITERIA AND LOADS
Built Environment Hazards in the Urban Habitat
Farzad Naeim and Marshall Lew
As disastrous as major earthquakes are, earthquake disasters and building performance provide valuable insight to design professionals, owners, and public officials for development of planning guidelines and building design and construction mitigations that may be utilized to minimize death and destruction of the urban habitat caused by future seismic events. It is imperative that we do not ignore the recent lessons learned and press on to implement needed changes to current societal, design, and construction practices. This paper provides a basic understanding of the major earthquake performance issues of importance worldwide, the lessons we have learned during the recent past, and the promising paths to a less risk-prone future.
As disastrous as major earthquakes are, they teach us important lessons that we as earthquake engineers and public officials may utilize to minimize death and destruction caused by future events. We need to optimise our learning process so that we learn new lessons from each earthquake rather than re-learning old lessons. We owe it to the people in general and to our clients in particular, to eliminate unnecessary death and devastation. The major known structural issues causing devastation of the built environment include:
|• Soft and weak story building configurations |
|• Poor material quality and workmanship |
|• Poor structural detailing |
|• Unaccounted for torsional response |
|• Weak column strong floor configurations |
|• Lack of adequate load paths |
|• Influence of "non-structural" components on building response |
|• Lack of adequate correlation between the building as analysed and designed and the building as built. |
These issues are explored in more detail in the following sections of this paper.