Q&A WITH OUR STRUCTURAL EXPERTS
Understanding Seismic Design A thorough comprehension of seismic design is essential in creating a building structure that can withstand earthquakes. However, seismic design considerations vary for different infrastructure projects, ranging from low-rise to high-rise buildings, metros and bridges. In addition, new trends have emerged over the past years which might form important design considerations. In this discussion, we have invited representatives from our structural specialist groups to explore these topics and discuss the possibilities of future collaboration.
What makes an effective seismic design? Juneid: The essence of successful seismic design is the collaboration within the design team, especially the architect and the structural engineer. Seismic design is unique in the sense that, unlike other common load conditions such as gravity or wind, design forces are based on the assumption that a significant amount of inelastic behaviour will take place in the structure during a design earthquake. In nearly all buildings designed today, survival in large earthquakes depends directly on the ability of the building’s structural system to dissipate energy while undergoing large inelastic deformations. The key to an effective structural seismic design therefore lies in the initial concept design of the structure which needs close collaboration with the architect. The broad guiding principles of a good seismic structural
Juneid Qureshi Group Design Director – Structural Meinhardt Singapore jq@meinhardt.com.sg
Peter Placzek Design Director/ Specialist Engineering Manager - Structures Meinhardt Australia peter.placzek@meinhardtgroup.com
design are:
Ensuring competent load path with direct transmission of seismic forces to the ground Providing redundancy Avoiding configuration irregularities through uniformity and symmetry Avoiding excessive mass Providing appropriate torsional resistance Detailing for controlled energy dissipation Limiting deformation demands
Mark Hennessy Director/ General Manager - Structures Meinhardt Australia mark.hennessy@meinhardtgroup.com
Doug Wallace Senior Engineer - Structures Meinhardt Australia doug.wallace@meinhardtgroup.com
It is important to note that complex analysis or design techniques should not be used to justify a poor concept design flouting the above fundamentals.