The Maturity Method has gained popularity in Canada over the last 10 years. While historically, it was used on mass pours, now we often see it being used on high-rise condo projects looking to quickly strip forms.
It is based on ASTM C1074 and an alternative to breaking cylinders, while also providing fast results that are more representative of a structure. You can estimate the Compressive Strength of Concrete using the time-temperature history of in-place concrete. A calibration curve is generated for a particular mix-design and then converted using a maturity index (Nurse-Saul or Arrhenius). this provides an estimated in-place concrete strength in real-time.