Inclination Angle Effect of Carbon Fibers in Cementitious Composites

Abstract

This paper presents an analytic model, which describes the bridging load and fiber stress developed when an inclined brittle fiber bridges a crack. The coupled effect of fiber bending and axial loading is explicitly accounted for. The model also considers matrix spalling and concentration of friction load at the point where the fiber bends over the matrix. With this model, it is possible to test the influence of fiber and matrix parameters on the bridging load and fiber stress, in order to achieve more efficient use of the fibers. Good comparison of the model predictions with experimental results of the inclined carbon-fiber test was achieved, both for the bridging load and the spall length. The model can serve as a useful tool to predict the efficiency of inclined fibers bridging a matrix crack.