Early life performance of a dual crystalline and a polymeric cementitious coating in concrete protection

Abstract

This paper reports results from a comprehensive laboratory investigation evaluating the performance of a dual crystalline and a polymeric cementitious protective material for underground concrete structures and structures subjected to water exposure. The amount of pollutants in terms of total dissolved solids (TDS); Potassium Chloride (KCl), 442TM and Sodium Chloride (NaCl) from the coating at the early stage, for the first 21 days after application, was compared against the standard criteria set by the World Health Organization (WHO) for drinking water quality. The results showed that both types of materials are effective in protecting the surface and the rate of pollutants decreases with curing time. The effective curing period for crystalline coating was 120-240 hours, while polymeric coating took shorter period 72 hours. In terms of water absorption, the crystalline coating outperforms its polymer counterpart at all curing times. The pull off test of polymer coatings on the rough and smooth substrates yielded results greater than 1MPa after 120 hours curing, while crystalline coating after 240 hours of curing. Cohesive failure was more common in the crystalline system, whilst adhesive failure was dominant in the polymer system.