NDT prediction of self-compacting concrete strength based on maturity method

Abstract

The maturity method is used as a non-destructive test to estimate the compressive strength of concrete. The main problem of this method is its dependence on the concrete mix design. This research presents a method for predicting the strength of self-compacting concrete in a specific range, without repeating the time-consuming and expensive standard calibration process. To demonstrate the ability of the method, 15 self-compacting concrete mix designs were prepared and their strength and maturity were determined at the ages of 2, 3, 7, 14, and 28 days. Based on the proposed method, the fc=a ln Ma+b relation was fitted to the mean of the data. Then scale factors for 3 mixes were calculated based on the early ages data (for example 3-day data) and the mix-specific strength-maturity curves were determined without a standard calibration process. The proposed method shows a high accuracy of more than 94% in these examples. Based on these results, it is not necessary to redo the entire calibration process within the reasonable range of changes in the mix design on the site, and the calibration curve can be presented in this way.