Abstract: To reveal the effect of iron ore tailing(IOT) and sand mud powder(SMP)on workability of cement paste , measurement of electrokinetic potential and rheological parameters were employed as polycarboxylic superplasticizer ( PCA) and naphthalene superplasticizer ( FDN) respectively with the two sorts of powders were added into cement pastes .The results show that the influence of IOT and SMP on the workability of pastes make remarkable difference .The rate of change of plastic viscosity and change ofζpotential keep significantly lower in the paste containing IOT compared with SMP by adding PCA ,the influence of IOT to the slurry liquidity and rheological properties is significantly lower .As FDN is used as admixture,great fluctuation of plastic viscosities of the pastes occur with increasing amount of fine powder , however workability of pastes with SMP is superior to of IOT with prolongation of time .When the mass fraction of powder in paste is 7%,the fluxility of paste will decrease .

Key words: iron ore tailing;sand mud powder;electrokinetic potential;plastic viscosity