Abstract:[Abstract] Joints are ubiquitous in engineering rock mass and affect engineering safety. The study of creep characteristics and constitutive model of rock mass with joints is of great significance for revealing creep mechanism of rock slope and predicting slope instability. The non-persistent hard joints samples were made from cement mortar, and shear creep test was carried out, and the creep properties were analyzed. The integer-order viscous pot element is improved to a fractional-order calculus software element, and the integer-order viscous pot element in the Kelvin model is replaced. At the same time, a non-linear viscous element which can simulate the accelerated creep process of joints is introduced and denormalized. The creep constitutive model of rock hard joints based on fractional calculus is constructed by means of component combination. The constitutive model is validated and the parameters to be determined are identified, based on the shear creep test data of non-penetrating and penetrating hard structures. The results show that the correlation degree between the experimental value and the predicted value is high, and the non-persistent hard joints and the persistent hard joints R2 are 0.94 and 0.97, respectively. It shows that the model can simulate the creep characteristics of rock mass with non-persistent and persistent hard joints, and is of great significance for revealing the creep mechanism and time evolution of rock slope.[Abstract] Joints are ubiquitous in engineering rock mass and affect engineering safety. The study of creep characteristics and constitutive model of rock mass with joints is of great significance for revealing creep mechanism of rock slope and predicting slope instability. The non-persistent hard joints samples were made from cement mortar, and shear creep test was carried out, and the creep properties were analyzed. The integer-order viscous pot element is improved to a fractional-order calculus software element, and the integer-order viscous pot element in the Kelvin model is replaced. At the same time, a non-linear viscous element which can simulate the accelerated creep process of joints is introduced and denormalized. The creep constitutive model of rock hard joints based on fractional calculus is constructed by means of component combination. The constitutive model is validated and the parameters to be determined are identified, based on the shear creep test data of non-penetrating and penetrating hard structures. The results show that the correlation degree between the experimental value and the predicted value is high, and the non-persistent hard joints and the persistent hard joints R2 are 0.94 and 0.97, respectively. It shows that the model can simulate the creep characteristics of rock mass with non-persistent and persistent hard joints, and is of great significance for revealing the creep mechanism and time evolution of rock slope.