Laing O'Rourke is using ground granulated blast-furnace slag (GGBS), a low-carbon cement alternative, at Everton FC's new stadium. Despite GGBS's longer cycle time, the team has been able to save three days per pour thanks to real-time maturity data from Converge sensors.
Laing O’Rourke are pouring a number of different concrete mixes at the new Everton FC stadium which consist of a higher volume of ground granulated blast-furnace slag (GGBS). GGBS is a low-carbon cement alternative that can be up to double its 28-day design strength after 10 years of curing.
The drawback, however, is that the cycle times are longer.
By using embedded Converge sensors in the slabs, and analysing real-time maturity data, Laing O’Rourke can claw back this time by striking falsework at the earliest opportunity, without delay.
After performing a calibration for each mix to be used, Laing O'Rourke were able to see real-time strength data on the ConcreteDNA platform. This allowed them to remove formwork as soon as each pour had reached strength (47 MPa), without delay.
Temperature/Strength graphs available in the platform were used by Engineers to document strike orders to remove formwork after strength had been reached.
On average, pour cycles were shortened by 3 days per pour. This translated to labour savings of 360 hours.
On a previous project, Laing O'Rourke had used an un-embedded solution which tended to get damaged and lose data.
Although you get value from the traditional test cube processes, being able to supplement these with more accurate real-time data from innovative sensors, has been beneficial in enabling us to determine actual in-situ strength gain within the poured slabs. While Converge Signal is more expensive, it works a lot better and we don't ever worry about losing data since we can collect it from our phones as a failsafe.
Gregory Deane, Senior Engineer, Laing O'Rourke
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