- Published on Friday, 20 April 2018 00:12
Wellington building evacuation demonstrates the need for more timely, better quality information.
Despite it now being 18 months since the Kaikoura earthquake, its effects on New Zealand's capital city of Wellington continue to reverberate. Yet another buildling, previously considered "safe", has been evacuated. Despite two earlier engineering inspections, it seems that further structural investigations have revealed significant issues. Further cause for concern is given by what appears to be quite different interpreations of what the observed damage actually means or implies.
The owner is to be congratulated on pursuing a rigourous approach. However, visual inspection remains a limited tool without further infromation. Rapid inspections (red, yellow, green placards) have been shown by experience in both Christchurch and Wellington to be of minimal use - with results often bearing no relation to eventual follow-up Detailed Engineering Inspections. On the other hand, the DEE process, by its nature involving the removal of wall, ceiling and roof linings, is time-consuming, disruptive and expensive. DEE's in Wellington are costing in excess of $20,000 - just to remove linings and begin the inspection process.
In cases such as this, CSI Structure Monitoring systems are an invaluable tool for both the owner and engineer. Such a system would have rapidly identified whether the damage (visible or not) had resulted in changes to the building response characteristics. Significant changes would have signalled alarm bells much earlier. A lack of change would have given the inspecting engineers confidence that, despite appearances, the the building was performing normally. Better, more timely information delivers more certain which in turn means reduced risk.
A good case study of the effectiveness of this approach is here. Media links to the Wellington building story are here: