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

Abstract

BACKGROUND: This 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). RESULTS:The 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. (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. Figure 1 shows the typical results obtained with this method, showing the change in mass of the cubes ([W t −W 0 ] A −1 ) as a function of t for the tested mixtures. Specimen designations in all J Chem Technol Biotechnol 2019; 94: 3488-3494 CONCLUSIONS: Addition 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 permeability

Opuntia Ficus-Indica (OFI) Mucilage as Corrosion Inhibitor of Steel in CO2-Contaminated Mortar

“…As observed in Figure 7 , the average IE% values for all OFI mucilage mortars were quite variable, and presented negative values when the mortar was in both dry cycles. This performance could be due to the fact that OFI mucilage retains water inside the mortar, as observed from previous investigations regarding the water absorption/desorption of mortars containing this biopolymer [ 3 , 4 , 5 , 6 , 7 , 8 ]. Nevertheless, i corr ranges in the dry cycle were very small, similar to passive steel in cement-based materials (between 0.01 and 0.06 μA·cm −2 ), thus no detrimental effects could be found in this dry environment for such low average i corr values.…”

“…Two OFI additions, for cement-based material durability improvements, were evaluated previously: OFI mucilage [ 1 , 2 , 3 , 4 , 5 , 6 ] and dehydrated OFI [ 7 , 8 , 9 , 10 ]. As explained in previous investigations, based on scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) characterization, OFI mucilage is a polysaccharide with several amino acids and sugars (arabinose, galactose, galacturonic acid, rhamnose, and xylose residues), as well as minerals such as calcium, potassium, and sodium [ 1 , 2 , 3 , 11 ].…”

Waste Matter of Cactus Cladodes (Opuntia spp.) Produced in Mexico for Innovation and Sustainable Development

“…Is considered as a natural organic additive, managed to be classified as a retarding agent, due to the moisturizing properties of the mucilage polysaccharide, increasing the setting time, incorporating it in cement pastes and mortar mixes replacing the water in the mix 38 . In addition, its use as a natural coating in facades built with adobe has been investigated to improve impermeability and decrease humidity 39 .…”

Effect of Dry-Wet Cycles on the Transport and Mechanical Properties of Cement Mortar Subjected to Sulfate Attack

“…At present, the permeability of cement-based materials under the coupled activity of dry-wet cycles and sulfate attack is rarely researched, especially with regard to gas permeability under osmotic pressure corrosion. The permeability of cement-based materials is one of the most important indicators of long-term durability [17,18], and the transport of internal material is closely related to changes in the pore structure [19][20][21]. There are many methods for measuring the permeability of cement-based materials [22][23][24][25][26], and among them, the gas permeability test method is easy to operate and has high accuracy [27].…”