The Kaushal and Tomita's () model, which has already been found satisfactory for broadly graded multisized particulate zinc tailings slurry with moderate concentration up to 26%, flow velocity up to 3.5 m/s in 105 mm diameter pipe, mean diameter 140 mu m, and geometric standard deviation of particles of 4.0, is tested for concentration distribution data collected by Kaushal et al. () on two sizes of glass beads, of which mean diameter and geometric standard deviation are 440 mu m and 1.2, and 125 mu m and 1.15, respectively, with concentration up to 50% and flow velocity up to 5 m/s in 54.9 mm diameter pipe. Kaushal and Tomita's (2002a) model gives more asymmetric concentration distributions. A modified model is proposed by alleviating some of the restrictive assumptions used in the existing model. Comparison of experimental data by Kaushal et al. (), Gillies and Shook (), and Matousek () with the proposed model is satisfactory.