Water and chloride permeability of cement‐based mortar with additions of dehydrated cacti

Abstract

AbstractBACKGROUNDThis investigation presents experimental results concerning water and chloride permeability of cement‐based mortar specimens fabricated with botanical (green) dehydrated additions such as Nopal (Opuntia ficus‐indica) and Aloe vera. Mortar without such additions served as control. The natural dehydrated additions, Nopal or Aloe vera, were mixed with ordinary Portland cement and sand at different percentages of cement replacement (0%, 1%, 2%, 4%, or 8% of the cement mass). To characterize water and chloride ion transport in such mortars, 5 × 5 × 10‐cm prisms were fabricated (three prisms per mixture).RESULTSThe results showed improvements in both water absorption‐desorption (on average: 10% decrease in capillary absorption; 6% increase in water penetration resistance; 58% decrease in effective capillary porosity; and 2% decrease in capillary sorption) and chloride transport (14% decrease in surface chloride concentration, and 31% decrease in chloride concentration at 7 cm into the mortar) within the dehydrated Nopal replacement mixtures (≤2% of the cement mass). Aloe vera additions did not improve the corresponding parameters of water and chloride ion transport into the mortar.CONCLUSIONSAddition of dehydrated Nopal (≤2% of the cement mass) powder to cement‐based material (mortar) may increase its durability as most aspects of durability are related to the absorption of aggressive agents (water, chloride ions, etc.) into the material through its network of pores. Additions of dehydrated Aloe vera did not improve the protective performance of mortar against water and chloride ion transport and are, therefore, not suitable for increasing the durability of such cement‐based materials. © 2019 Society of Chemical Industry