Effective Highly Dispersed Additive for Concretes on the Basis of Natural Mineral Raw Materials

摘要

The composition of a highly dispersed additive for concrete based on the natural mineral raw material wollastonite is developed. The properties of the modified fine-grained concrete (FGC) are studied. The three-factor experiment planning made it possible to obtain mathematical dependences of the bending and compressive strength after 3 and 28 days of hardening, density, and water-cement ratio of the fine-grained concrete on such factors as the content of anionic surfactant of naphthalene-formaldehyde type in the composition of the raw material wollastonite being an activator of mechanic-chemical processing, the suspension stabilizer of the pre-activated material, and the content of S-3+wollastonite in powder after mechanic-chemical activation in the suspension. The dependence nomograms are built. The optimal strength parameters of the modified fine-grained concrete with the content of a highly dispersed additive of 5% by weight of cement in its composition, and the wollastonite concentration of 3 g/l in the water medium of the suspension stabilizer S-3 are ascertained. The developed highly dispersed additive allows obtaining finegrained concrete with the bending strength of 3.1 MPa and the compressive strength of 57.8 MPa.