Abstract This study presents a new method for measuring the shrinkage of repair materials in repaired concrete structures. Three cylindrical models and a half-scale beam were constructed; these included three types of repair materials and three types of interface surfaces between substrate and repair materials. The unrestrained shrinkage of repair materials was measured and compared with that of restrained samples. The proposed cylindrical model with a smooth concrete interface had the best conformity with the beam model for all repair materials. This new model can be considered for prediction of the real shrinkage in repaired structures.