Southeast Asia Construction – May – Jun 2010
Technologies for waterproofing concrete from the inside out are gaining in popularity. This has led to a plethora of new products that work within the concrete itself to create a watertight structure that lasts The East Bayfront development in Toronto, Ontario, Canada is currently underway to offer 7,000 residential units, more than 5 ha of parks and public spaces, and employment for 8,000 people. At the heart of the project is Sherbourne Park, a spectacular new waterfront park that will transform a formerly industrial area into much needed public greenspace on the lake.
Located just east of Lower Sherbourne Street, the 1.5 ha Sherbourne Park spans more than two city blocks, from Lake Ontario in the south to Lake Shore Blvd in the north, on both sides of Queens Quay. The north side of the park features a grove of pacific sunset maple trees, benches and play structures creating an outdoor living room for East Bayfront residents. Wide open greenspace on the south side of the park provides ample space for festivals, concerts and other city-wide events overlooking Lake Ontario. In total, the park includes 182 new trees, 26 play structures and 49 benches.
Construction of the park, which started in July 2009, began on the south side of Queens Quay where the Sherbourne Park Pavilion is located. This 144 sq m zinc clad and glass structure will house a cafe and facilities designed to enliven the park year-round. It is surrounded by a 920 sq m pond that will be frozen in the winter for a skating ring and act as a splash pad in the summer for waterplay. The park is expected to open to the public in the middle of this year.
Sherbourne Park is designed by landscape architects Phillip Farevaag Smallenberg in association with The Planing Partnership. Eastern Construction Company is the construction manager for the project along with multiple subtrade partners. The federal government has committed CA$20.8 million for the project, with the city of Toronto and province of Ontario funding the remaining $CA8 million.
An impressive feature is the stunning 240 m long water channel that runs the entire length of the park. The channel transports Ultra Violet-treated stormwater from the treatment facility under the Pavilion to Lake Ontario. A biofiltration bed is incorporated at the north end of the channel, which further treats the water, making it clean before discharging it into the lake.
Kryton’s integral crystalline waterproofing admixture, Krystol Internal Membrane (KIM), is being used to waterproof the water channel, which is made of concrete with a light sandblasted finish. It is particularly applied to the walls and slab of the channel to ensure a watertight seal. This is not only to prevent leaks and contamination, but it is also to withstand freeze-thaw cycles during icy winters in Toronto.
Kryton’s KIM offers an excellent waterproofing solution by turning the concrete itself into the water barrier. When combined with water, proprietary chemicals that make up KIM react to form millions of needle-like crystals. These crystals grow and fill the capillary pores and micro-cracks in the concrete, blocking the flow of water. As time passes and stresses form new cracks, any incoming moisture causes the crystals to reactivate, ensuring continuous waterproofing over the years.
By waterproofing from the inside out, integral crystalline waterproofing products have several major advantages. They are invulnerable to damage in that they cannot be scraped, punctured or torn. There are also no workmanship issues to be concerned with because installation of a membrane is not required. And because time is not wasted on surface preparation and membrane installation, backfilling and other crucial construction processes can proceed without delay.
Kryton’s KIM is also an environment-friendly alternative for creating waterproof concrete. It extends the life of concrete structures, reduces jobsite waste by being available in pulpable bags that go directly into the ready mix trucks, and enables the future recycling of concrete materials.
Furthermore, KIM contains no volatile organic compounds. It is non-toxic and safe for contact with potable water.
The concrete started to be poured into the wooden formwork – which acts as a mould for the channel – early this year. By March, nearly 50 percent of the pour had been completed. Work is carried out under a large white tent to protect the concrete from the winter elements.
In all, more than 12,000 kg of KIM has been used to waterproof the channel.