A new earthquake resistant, fibre-reinforced composite material developed by Civil researchers has been taken out of the lab and into the real world for a trial application at a Vancouver elementary school.
Older buildings in cities like Victoria, Vancouver, and Portland, especially unreinforced masonry buildings, are at risk for structural damage or collapse in a major earthquake event. Unreinforced masonry walls, such as those built from bricks or hollow blocks, are prone to collapse when shaken, which can cause dangerous bursts of debris and significant loss of life. In Vancouver, many schools are housed in seismically vulnerable heritage buildings with walls like this, and the Ministry of Education has made retrofitting these buildings a priority.
In the ongoing search for new effective, low-cost techniques for seismic retrofits, UBC civil engineers have come up with a promising solution. Under the supervision of Professor Nemy Banthia, graduate students in the SIERA Group have developed a high ductile and bendable concrete material called eco-friendly ductile cementitious composite, or EDCC; and PhD candidate Salman Soleimani Dashtaki has demonstrated the efficacy of spraying a thin layer of EDCC on unreinforced masonry in significantly enhancing its resistance to earthquakes. EDCC is a concrete-like material made of a special blend of fibres and cement mortar that can be applied in thin layers as a reinforcement to masonry walls. Its unique composition means it can bend without breaking, allowing it to hold blocks and bricks in place and prevent collapse under violent shaking. EDCC also offers an environmental advantage. The production of cement, used in concrete, is responsible for a significant volume of greenhouse gas emissions. In the formula for EDCC, much of the cement used in typical concrete has been replaced with flyash, an industrial byproduct which is produced in excess of 500 MT annually around the world.
This innovative material has been shown in the UBC Civil laboratories to be effective – test walls with ten millimetre layers of EDCC applied stood up to simulated earthquakes, when the same walls without EDCC, subject to the same intensity of shaking, did not. To try out this promising new material in a real-world setting, the Civil researchers have applied EDCC to a wall at Dr. Annie B. Jamieson Elementary School in Vancouver.
This innovation has received extensive media coverage – selected stories are linked below.
CTV Vancouver video (at 18:30 mark): http://bc.ctvnews.ca/video?binId=1.1184759
Professor Banthia’s Interview on CBC On The Coast (at 59:30 mark)