Prediction of concrete strength by hierarchical stepwise regression using ultrasonic pulse velocity and Schmidt rebound hammer

Non-destructive testing methods, such as the ultrasonic pulse velocity and Schmidt rebound hammer tests, are essential in determining the compressive strength of concrete. These methods have several benefits, including not needing sampling, being easy to execute, and delivering quick and efficient results. However, it’s crucial to understand that these methods can occasionally produce estimates that significantly deviate from the actual experimental values of compressive strength, resulting in a broader dispersion of results. Current research is centered on analyzing existing equations and formulating a new, improved model for predicting concrete’s compressive strength. Hierarchical stepwise regression is used to predict concrete compressive strength using experimental data from ultrasonic pulse velocity and Schmidt rebound hammer tests. The results showed that the accuracy of the new equation surpasses that of the existing equations in the literature, achieving an coefficient of determination R² value of 95.53%. Additionally, the new model outperforms the available equations by exhibiting lower errors (1.68, 5.00 and 2.23)% across various metrics such as (MAE, MSE and RMSE) respectively. As a result, this new equation can serve as a reliable and robust method for estimating the compressive strength of concrete.