Rheological properties of mineral-cement mix with foamed bitumen with the addition of redispersible polymer powder

The main objective of the research presented in this article was the search for response concerning the influence of redispersible polymer powder (RPP) on the rheological properties (evaluation of the complex modulus and phase shift angle) of a mineral-cement mix with foamed bitumen (MCAS). Redispersible polymer powders are used in the construction industry as ingredients of mortar, cement concrete, plaster, adhesives and tile cement. However, literature related to an analysis of the influence of redispersible polymer powders on the properties of a mineral-cement mix with foamed bitumen (MCAS). The objective of the research was executed through the use of known identification methods in terms of rheological properties. The analysis of the complex modulus was conducted spanning linear viscoelasticity for deformation spanning 25 to 50 μstrain per PN-EN 12697-24 annex D. The test set-up assumes the determination of the complex modulus E* and the phase shift angle φ at the full sine wave for direct expansion and compression using cylindrical samples (DTC-CY). Using the redispersible polymer powder for MCAS can improve hydrophobic properties and limit rigidity, together with an improvement of the elasticity of the mineral-cement mix with foamed bitumen (MCAS). The increase of elasticity of the MCAS can be caused by a modification of the mineral matrix and a disclosure of interactions between the aggregate-cement and the polymer. In case of a recycled substructure, this phenomenon is significant due to the placement of the substructure in an arrangement of construction layers (increased humidification). Test results have shown a reduction of the complex modulus and the emergence of the effect of the polymer at high temperatures and after a prolonged load period.