Determination of Concrete Strength for Concrete Pavement Opening Decision-Making

Improving early-age concrete strength measurement is an important step toward opening new pavements to traffic quickly without risking long-term performance due to early age damage. The maturity method is well established as an appropriate estimation of strength; however, it contains certain unavoidable limitations. Non-destructive ultrasonic testing using shear wave velocity can be used as a complementary testing. An in-situ comparison of these strength estimation methods was performed on a 200-mm thick concrete pavement for two weeks after placement. Both methods predicted reasonable concrete strength gain trends for in-situ pavement. The linear array ultrasonic method was found to have major advantages regarding portability, strength-gain variation and testing speed.