Effect of metakaolin on rheology of polymer modified cement paste
The effects of metakaolin content on the fluidity,rheological parameters,thixotropy,and vis-coelasticity of polymer-modified cement pastes with different water-to-binder ratios were studied.The re-sults showed that the rheological properties of the fresh composite paste incorporating metakaolin conform to the H-B model during the initial mixing stage,and all the pastes show the rheological characteristics of shear thinning.With the increase of metakaolin content,the fluidity,yield stress,and plastic viscosity of the paste all increase.After adding 20％metakaolin,the thixotropic loop area of cement paste increases from its original value of 1 502 Pa·s-1 to 6 672.63 Pa·s-1,and lower water-to-binder ratio pastes corre-spond to a larger thixotropic area.All the composite pastes have obvious viscoelastic properties,and the critical strain amplitude and storage modulus values of linear viscoelastic range increase as the metakaolin content increases.
万方数据
维普
