<p>Within the domain of rock slopes characterized by intermittent fracturing, these fractures are the primary cause of slope instability, with the bearing capacity of rock bridges between fractures serving as the key to stabilizing the rock mass. This study conducted numerical investigation on rock masses with coplanar intermittent fractures based on continuous yield contact model. The mechanical properties under different loading conditions, size effect on fractured rock masses, and shear failure behaviors of rock bridges and their influencing factors were analyzed and discussed. The shear strength of rock masses is determined by peak strength, residual strength, and the load borne by the elastic deformation of rock bridges at various positions. Moreover, the strength of fractured rock masses exhibits negative size effect, which is further discussed and considered to be caused by the interaction between cohesive and internal friction angle during the loading process. The progressive failure behavior, a typical characteristic of rock masses with intermittent fractures, is manifested as the gradual breakdown and load transfer of the proximal bridge. Additionally, the multiple primary fractures elongate the elastoplastic deformation, and the lower elastic modulus promotes the progressive failure. The findings from this research are expected to contribute to understanding the failure process of complex fractured rock masses and revealing the disaster evolution mechanism of locked rock slopes.</p>