Effect of pig slurry on two cement mortars: Changes in strength, porosity and crystalline phases

The present article addresses the variations observed in porosity and flexural and compressive strength in two types of cement mortar when submerged in pig slurry. The tests were conducted in a 100 m3 experimental lagoon. The mortars were exposed to three types of environments for 36 months: two submerged in the test lagoon, at two different depths, and one outside it. Bending and compression measurements were taken after 3, 12, 24, 36 and 48 months. In addition, 3, 24, 36 and 48 month specimens were tested for total porosity and pore-size distribution. Changes in the mineralogical characteristics of the mortars after 24, 36 and 48 months were also recorded. The strength studies showed that the load capacity attained by the two cements was similar after 48 months, the use of more expensive 42.5 sulphate-resistant cement is not justified. The XRD results showed no evidence in any of the cements of precipitation originating in the ions in the aggressive medium.