Influence of crystallizing additives on stabilized mortars produced in plants

ABSTRACT

Stabilized mortar has emerged in the construction market as an industrialized alternative for increasing productivity. However, its performance is dependent on additives, making it relevant to assess the behavior of admixtures adapted from concrete technology. In this context, the influence of crystallizing additives—widely used for waterproofing concrete—is still incipient, representing a technical gap regarding their actual impact on mortar properties. In this scenario, this study investigates the influence of incorporating two types of crystallizing additives (Type 1 and Type 2) on the properties of stabilized mortars produced in plants. For this purpose, the effects of the additives were evaluated at three dosages (0.35%, 0.70%, and 1.00%) relative to the cement mass. Seven samples were tested: one reference and six with the admixtures, subjected to tests in the fresh state (consistency, air content) and hardened state (bond strength, compression, and flexural strength). The results indicate that although the crystallizing additives improve workability retention over the period of use, their impact in the hardened state is critical. It was found that certain dosages did not meet the minimum requirement for tensile bond strength, demonstrating that the addition of these components can compromise the mechanical performance of the mortar.

Keywords:
Stabilized Mortar; Properties; Additive; Crystallization; Permeability