Correlation of non-destructive and destructive testing of concrete modified with rice husk ash and brick aggregate

Abstract

Concrete structures may deteriorate over a period of time. Nowadays, to determine the extent of damage, various tests are being performed that are non-destructive by nature. A proper correlation between destructive testing (DT) and non-destructive testing (NDT) may enhance the use of NDT applications in the field of concrete structures. Although several correlations have been suggested by other authors for standard concrete, the correlation may change with the use of non-conventional materials such as rice husk ash (RHA) and brick aggregate (BA) in concrete. In this paper, NDT methods such as ultrasonic pulse velocity (UPV) testing and rebound hammer testing, as well as DT methods such as compressive strength testing, were performed on a special type of concrete in which BA was used as coarse aggregate and RHA was used as the partial replacement of cement. This modified concrete has been abbreviated as RHA-BA concrete. Material-specific prediction models based on linear regression and artificial neural network (ANN) were established after using the data from concrete specimens. A strong correlation was observed between NDT and DT when the RHA percentage was low. The best correlation between NDT and DT was found at 5% RHA. An RHA percentage beyond this yields a weaker correlation between NDT and DT. The linear regression model along with the k-fold validation technique and the ANN model have both proven to be efficient in predicting the compressive strength of RHA-BA concrete; however, the ANN model has proven to be more efficient than the linear regression model with a lower mean squared error (MSE) and higher R-square values.