Simulation the Effects of Fiber on the Poisson's Ratio of Self-Compacting Concrete

The present paper studies experimental research on the effects of fiber on the strain and the Poisson's ratio of self-compacting concrete (SCC). The experiment was carried out on 48 cubic concrete samples and 68 standard cylindrical samples of 4 different mixes with compressive strengths of 25, 28, 30, and 33 MPa. The percentage of fiber in the mixes increases from 0 to 12. Axial and lateral strains of the samples were calculated simultaneously, with respect to the stress exerted by uniaxial compressive loading. Having compared the stress-strain curves for axial and lateral strain, Poisson's ratios were calculated by taking the number of the loadings into account. One of the implications of the results was that the ratio of the inner area in lateral stress-strain curve to those in axial stress-strain curve relate to the square of Poisson's ratio in the same percent of fiber. At the end, with respect to the concrete's compressive strength and percentage of fibers, an integrated model was formulated for Poisson's ratio of fiber SCC under compressive loading. The results show that an increase in fiber (only 2%) causes a significant increase in Poisson's ratio (more than 5%) after the second compressive loading. Also, the third lateral strain provides maximum strength in all self-compacting concrete mixes.