Analytical analysis of drying shrinkage of SFRC based on experimental results

Abstract

In order to find out the influence of different fibre dosages on the drying shrinkage of SFRC, an experiment was carried out at the Faculty of Civil Engineering–Skopje. The experiment consists of 9 specimens which were manufactured with concrete class C30/37, and according to the type of material they were divided in three series: Series A, ordinary concrete (C30/37); Series B, SFRC with 30 kg/m3 steel fibres (C30/37 FL1.5/1.5) and Series C, SFRC with 60 kg/m3 steel fibres (C30/37 FL2.5/2.0). According to the experimental results at the age of concrete of 400 days, the addition of steel fibres has almost no influence on the free drying shrinkage (decrease up to 2%). Based on the experimental results up to an age of 400 days, the analytical analyses of drying shrinkage were performed by the B3 model and fib Model code 2010 and were prolonged up to the age of service life of structures of 100 years. It was concluded that the fib Model Code 2010 underestimates the drying shrinkage strain for 29%, while the original B3 model for 11.5%. An improvement of the B3 model is proposed by updating the drying shrinkage strain with calculation of a scaling parameter p6.