Estimation of fractional critical tractive stress from fractional bed load transport measurements of unimodal and bimodal sediments

Experimental investigation on estimation of fractional critical tractive stress of nonuniform unimodal and bimodal sediment mixtures is reported. The observed data on fractional bed load transport rates for different flow strength, under equilibrium condition, have been used to estimate critical tractive stress (CTS) of each size fraction in sediment mixture from reference transport method (RTM). Further, the accuracy of these estimated CTS values are assessed by comparing the same with CTS values estimated using largest grain method (LGM). The estimated CTS values of individual size fractions for different sediment mixtures have been used to assess the performance of CTS relationship recently proposed by Patel et al. [12].