Experimental Study on Angular Flexural Performance of Multiaxis Three Dimensional (3D) Polymeric Carbon Fiber/Cementitious Concretes

Multiaxis three-dimensional (3D) continuous polymeric carbon fiber/cementitious concretes were introduced. Their angular (off-axis) flexural properties were experimentally studied. It was found that the placement of the continuous carbon fibers and their in-plane angular orientations in the pristine concrete noticeably influenced the angular flexural strength and the energy absorption behavior of the multiaxis 3D concrete composite. The off-axis flexural strength of the uniaxial (C-1D-(0 degrees)), biaxial (C-2D-(0 degrees), and C-2D-(90 degrees)), and multiaxial (C-4D-(0 degrees), C-4D-(+45 degrees) and C-4D-(-45 degrees)) concrete composites were outstandingly higher (from 36.84 to 272.43%) than the neat concrete. Their energy absorption capacities were superior compared to the neat concrete. Fractured four directional polymeric carbon fiber/cementitious matrix concretes limited brittle matrix failure and a broom-like fracture phenomenon on the filament bundles, filament-matrix debonding and splitting, and minor filament entanglement. Multiaxis 3D polymeric carbon fiber concrete, especially the C-4D structure, controlled the crack phenomena and was considered a damage-tolerant material compared to the neat concrete.

Automated summary

The angular flexural properties of multiaxis three-dimensional continuous polymeric carbon fiber/cementitious concretes were experimentally studied, showing outstanding flexural strength and energy absorption behavior compared to neat concrete. The fracture behavior of the polymeric carbon fiber concrete was controlled, making it more damage-tolerant than neat concrete.