ACCURACY OF PREDICTION MODELS FOR SHRINKAGE OF CONCRETE

Seven shrinkage models were compared with data measured on 46 Australian concretes containing over 1500 data points, using the method of residual plotting. This method is superior to the current methods of presenting shrinkage data, as the method of plotting shrinkage residuals enables inaccuracies in the shape of shrinkage-time curves to be identified readily. The more complex shrinkage models were not necessarily more accurate than simple models. The introduction of such parameters as water-cement ratio, aggregate grading, and air content may not necessarily lead to improved accuracy of the models, and some of the recently presented models performced poorly for the Australian concretes used in this study. The simple Australian Code AS1481 performed better than the other models for the prediction of shrinkage.