Whilst many people associate Australia with extreme weather that can include very high temperatures, drought and powerful storms, they probably don’t immediately think of earthquakes as being a particular problem. However, although they occur only infrequently, they are more common than many people think and can be a severe threat. Most people will be aware […]
Whilst many people associate Australia with extreme weather that can include very high temperatures, drought and powerful storms, they probably don’t immediately think of earthquakes as being a particular problem. However, although they occur only infrequently, they are more common than many people think and can be a severe threat. Most people will be aware of the Christchurch, New Zealand, earthquake in February 2011 that had a devastating effect but there have been others closer to home although on a lesser scale.
The last time Australia was hit really badly was in 1989 when Newcastle in New South Wales suffered an earthquake measured at 5.6 magnitude, which caused thirteen deaths, over 150 injuries and damage to around 50,000 buildings. Lesser tremors have been experienced since then and regulations are now in place to reduce the effect of future seismic activity.
The country’s National Construction Code previously had no content regarding the need for provisions against earthquakes in new buildings. This changed in 1993 when the Australian Standard AS1170.4 was adopted and any buildings constructed since then should comply fully with it. If so, they will have sufficient structural resistance to both vertical and horizontal earthquake movements since they will be built to absorb energy from the seismic activity and so there should be little danger of collapse.
However, any buildings constructed after 1993 but up to 2019 are likely to have little or no resistance to seismic activity for their non-structural elements. These are generally considered to include mechanical plant and equipment, including HVAC, electrical fittings, plumbing, internal walls and ceilings. None of these are likely to satisfy the current seismic requirements for Sydney.
Section 8 of AS1170.4 now requires that non-structural components have to be considered in respect of vertical and horizontal earthquake movements. This section has been adopted by the Australian Building Codes Body and other authorities since 2019 so all non-structural components must now be designed and built with seismic capabilities so they can withstand severe movements. Components fitted to buildings should be completely secure and will be capable of holding secondary components so they are not shaken loose.
The National Construction Code, which contains the Building Code of Australia that includes AS1170.4, requires that all class 2 to 9 buildings have to perform adequately under design actions that can be reasonably expected, which includes the actions of earthquakes. This applies to all buildings except those in class 1 (individual dwellings) and class 10 (those that are not habitable). Nevertheless, class 1 buildings have to be designed and built to resist strong lateral wind forces, which means they’re also expected to be able to resist equivalent forces from earthquakes. So they all, effectively, require a good deal of compliance for seismic for non-structural in Sydney.
Ensuring seismic compliance for Sydney need not be an expensive or time-consuming business if you choose the right building supplier in Sydney. All Nashco’s lightweight steel wall framing in Canberra and suspended ceiling systems are designed and manufactured with in-built bracing and of sturdy materials that ensure they’ll give more than adequate resistance to seismic activity if fitted properly.
Earthquakes with a magnitude of five to six are predicted over the next few years. The last one of such a size caused extensive damage so, apart from the need to comply with regulations, it’s sensible and practical to ensure as far as possible that buildings are completely resistant to earthquake activity. This applies to the non-structural components for seismic activity in Sydney as well as the building itself and will avoid death and injury while also limiting damage and keeping buildings usable.
