The Decay of the Historical Site of Malecon in Havana, Cuba: Salt Crystallization Damage at Repair Interfaces

Abstract

The buildings of the Malecon, the historical section of Havana along the coastline, suffer accelerated degradation due to the aggressive environment. The primary damage mechanism at play is the crystallization of sodium chloride at repair mortar interfaces, as shown in petrographic and SEM analysis. This preferential precipitation leads to crystallization pressures that reduce the adherence of the lime based mortars from the substrate. Environmental monitoring shows that the daily relative humidity fluctuates around the deliquescence point of sodium chloride, exacerbating the problem through continual cycles of dissolution and recrystallization. The potential for an alternative repair material such as limestone calcined clay cement based mortar is discussed.