Space-Averaged Constitutive Model for HPFRCCs with Multi-Directional Cracking

摘要

This paper focuses on the numerical modeling of high-performance fiber-reinforced cementitious composites (HPFRCCs), specifically polyvinyl alcohol engineered cement composites (PVA-ECCs) in the context of a space-averaged, fixed-crack approach. Compression, tension, and shear models are proposed. The compression and tension models include internal unloading and reloading paths. The shear model considers the shear stress transfer contributed by surface friction and fiber bridging in a phenomenological manner. The applicability of the models is verified against recent experiments on precracked PVA-ECC plates subjected to principal stress rotation, demonstrating that the proposed models replicate various responses of the plates. The degradation of initial stiffness and the overall strength of plates with precracks at different angles is represented well. Finally, this paper demonstrates the ability of the models to replicate the average strains spanning bidirectional multiple cracks occurring at the bottom surface of the precracked plates.