81 Bay, a monumental, forty-nine storey, office and retail development in downtown Toronto was built leveraging EXACT’s state-of-the-art temperature, strength and formwork monitoring technology.

The project had very demanding requirements in terms of concrete design. It required a mix that could achieve a high early strength in order to keep to a very tight schedule, moving forms every 12 hours. The immense size of the building’s core made this particularly challenging. With pour volumes around 850m3 per pour, the concrete needed to remain sufficiently fluid to be placed monolithically. EXACT’s temperature monitoring solution for mass concrete elements offered the ideal tool to ensure the core remained within specified limits for maximum temperature and maximum temperature differential.

To keep to the tight schedule requirements, the project team also relied on EXACT’s maturity monitoring for the core and suspended lobby slabs. The system alerted them when concrete strength approached the requisite 16MPa for jacking the self climbing formwork system to the next level and the 75% strength required within the lobby slabs. Without insitu monitoring, such a quick floor turnaround simply would not have been possible to achieve — it would have been nearly impossible to rely on “field cured” cylinders to provide representative strengths at 81 Bay’s high elevations.

The project team also utilized EXACT’s pressure monitoring system to understand the limits of their pour rates. The concrete used was self-consolidating, and, due to long placement rates, the forms were designed for less than hydrostatic pressure. As such,  monitoring was necessary to understand the actual pressures exerted on the formwork based on mix and pour rate.

Finally, the use of EXACT’s monitoring systems throughout delivered an accurate understanding of how the highly-specialized concrete mixes performed. As a result, the project team could maintain concrete quality control over the mixes.