▎ 摘　　要

Cement mortar lining (CML) is commonly used for iron pipe internal corrosion inhibition in drinking water distribution system (DWDS), however, the corrosion of CML itself is still a problem, particularly under soft water conditions. In this study, both long-term experimental study and theoretical studies were conducted to evaluate the effects of graphene oxide (GO) and three-dimensional reduced graphene oxide (3D-rGO) as additives on the stability of CML and the corresponding water quality. Results showed that during a 182-day leaching experiment, the 3D-rGO modified cement had a higher ability to inhibit the cement constituent leaching than GO modified and original cements. Structural characterization indicated that the addition of 3D-rGO could slightly promote the degree of calcium hydroxide crystallization in CML. Molecular dynamics simulation demonstrated that the 3D-rGO nanosheets strengthened the tensile strain of the cement and restricted the movement of calcium ions by forming strong bonds with the calcium-silicate-hydrate gel network. In addition, compared with GO modified cement and original cement, the 3D-rGO modified cement could somewhat reduce the disinfection by-products formation and the microbial richness in drinking water. Thus, the reinforcement of cement by 3D-rGO could enhance the safety and durability of CML iron pipes in DWDS.