Concrete for Road Pavements

Abstract

To create a high performance road concrete it is advisable to use two complex additives simultaneously with the aim of increasing concrete density, strength, hardness, corrosion resistance and durability.A complex admixture on the basis of a mix of polycarboxylate polymers modified by inorganic substances including nanostructure elements SiO2×nН2О which are parts of silicic acid was developed as an admixture of polyfunctional action (activating and plasticizing actions).To increase crack resistance and tensile strength in bending and to decrease abrasion another complex admixture on the basis of sparingly soluble salts of magnesium modified by silica with different particle sizes was developed too.Concrete with these two additives used in rational quantities is characterized by 58-59% increase of compressive strength and 83-91% increase of tensile strength in bending, with coefficient of crack resistance rising by 17-20%. The concrete abrasion corresponds to the G1grade of concrete and the concrete freeze resistance – to F 2600 grade. The concrete water absorption is reduced by 40%. This increases the concrete density. Corrosion resistance of the modified concrete at the age of 360 days is raised more than 15%.The amount of sparingly soluble hydrated compounds is increased when these two additives are applied together. The concrete designed with given additives is recommended for creation of an effective pavement.