Property comparison of steel slag cement mortar with hydroxyethyl methyl cellulose having different degrees of substitution and PAAm modification

The aim of this study is to explore the influence of HEMC with different total substitution degrees and polyacrylamide (PAAm) modification on the properties of steel slag cement mortar. The results show that HEMC increases the water retention rate, consistency, tensile bond strength, and flexibility of all types of steel slag cement mortars. The addition of HEMC, however, leads to a decrease in compressive strength and flexural strength. The total substitution degree or PAAm modification of HEMC has a minor effect on the water retention rate, compressive strength, flexibility, and pore size distribution of steel slag cement mortar. HEMC with a higher total substitution degree is more beneficial to the development of tensile bond strength except for SL1 cement mortar at an early age (3 days and 7 days), whereas PAAm weakens the positive effect of HEMC on the tensile bond strength. Mercury intrusion porosimeter (MIP) tests show that the addition of HEMC increases the porosity of steel slag cement mortar.