The answer to Earthquake-proofing: EDCC
Approximately 14,000 earthquakes occur in and around New Zealand each year, of which at least 150 are big enough to be felt. The last decade has seen over 25 of those reach a magnitude higher than 6.0. Officials have been researching ways to increase safety and prevent buildings from collapsing under an earthquake with such high magnitudes.
EDCC (eco-friendly ductile cementitious composite) may be the solution they have been looking for. Essentially, this coating is a combination of cement and polymer-based fibres, flyash and other industrial additives. Developed by University of British Columbia, Vancouver, EDCC is engineered at the molecular scale to be strong, flexible and malleable – similar to steel. This dramatically improves the earthquake resistance of a seismically vulnerable structure when applied as a thin coating on the surface.
EDCC can withstand an intense earthquake
In 2011, Japan was rocked by what is now known as the Great East Japan Earthquake. The earthquake had a magnitude of 9.0 – 9.1 – the fourth most powerful in the world. Researchers took this as a benchmark for EDCC and tested the composite using this high intensity as seen in the video below:
The highest magnitude recorded in New Zealand was 8.2 back in 1855. Between the rebuilding of cities and the use of appropriate building methods, this coating would be more than capable of withstanding Kiwi earthquakes.
Wellington in need of Earthquake-resistant Coating
If it was possible, the capital city would undergo a city-wide earthquake-proofing exercise. The city is in the highest-risk zone and is most susceptible to earthquakes and tremors.
Property mogul, Ian Cassels, has plans to implement EDCC in his Wellington buildings, stating that the price of NZ$ 12 per meter is a reasonable price for this engineered type of coating. Erskine College and other properties on Cuba Street are in line to be coated.
Salman Soleimani-Dashtaki, a researcher, also believes this coating is perfect for Wellington’s heritage buildings. EDCC can be applied to just the rear of a wall, without changing the appearance of the front.
How can you buy EDCC ?
EDCC is still in its pilot phase with the technology being used to retrofit British Columbia’s seismic retrofit program. Schools in Canada and India will be upgraded soon to protect them from collapsing in the event of an earthquake.
For the use of EDCC to be permitted in New Zealand, its manufacturers would first have to prove it meets the Building Code guidelines. Provided it does meet these standards, it would only make it to your local Bunnings store long past March 2018. In the meantime, house owners are being advised to secure their masonry using alternative avenues such as;
- Wood to secure façades
- Precast concrete
Not only safe for humans but for the environment too
EDCC was developed with the environment in mind. Approximately 70% of cement is replaced with flyash. Consequently, reduction in the amount of cement used translates to a significant decrease in the amount of carbon dioxide released into the atmosphere during production.
Considering that the cement industry contributes almost 7% of global greenhouse emissions, the use of EDCC would be a step in the right direction for the future.