Fabrication of integrally hydrophobic self-compacting rubberized mortar with excellent waterproof ability, corrosion resistance and stable mechanical properties

Abstract

Ordinary cement-based materials exhibit strong hydrophilicity and brittleness after hardening, which is very detrimental to their durability and service life. In this study, a low-cost and nontoxic silane-based hydrophobic agent and waste tire rubber particles are used to make integrally hydrophobic self-compacting rubberized mortar (HSCRM). The fluidity of the HSCRM is enhanced and its setting time is prolonged with increasing hydrophobic agent content. When the content of the hydrophobic agent is 2%, the HSCRM exhibits integral overhydrophobicity, with the static contact angle (CA) on the surface larger than 120°. In addition, compared with the self-compacting mortar (SCM), the immersion water absorption and capillary water absorption of HSCRM decrease by 72.1% and 89.3%, respectively, while the corrosion resistance of the HSCRM is significantly enhanced and its surface deicing process is much easier. Moreover, the 28 d flexural strength, compressive strength and splitting tensile strength of the HSCRM are 18.9%, 32.3%, and 17.2% lower than those of the SCM, respectively, but the toughness and ductility of the HSCRM are significantly improved.