Fresh granular-pasty materials are considered as an intermediate class between solid and fluid. These materials are capable of showing their rheological behavior which can be close to either a pasty or granular system depending on properties and proportion of ingredients in the mixture. Therefore, quantification of such dependencies is a crucial factor in order to be able to predict the performance of this type of material. In this study a two phase model is considered in which a mixture is decomposed into a paste and a granular phase. The relation between the aggregate grading and the consistency of the mixture has been investigated for a concrete in which the pasty behavior is dominant. It was found that if the volume and property of the paste that remains after filling the space in between the aggregates in compacted state is kept constant, the consistency of a mixture can be characterized by the number of aggregates corresponding to each grain size regarding the sieve analysis test. The paper presents a modelling approach and experimental results.