▎ 摘　　要

Early-age strength and fracture toughness of alkali-activated geopolymer cementitious materials are important factors affecting their engineering application. In this paper, early-age mechanical properties of reduced Graphene Oxide(rGO) geopolymer cement composites were investigated. By contrast to Graphene Oxide(GO), rGO have showed a competitive advantage in early-age mechanical properties of alkali-activated geopolymer cement. With 0.06 wt% rGO geopolymer cement composite, 1 day and 3 days flexural strength increased by 66.7% and 40%, 1 day and 3 days compressive strength increased by 28.5% and 23.9%, respectively, compared to the blank sample without rGO. The results indicated that the incorporation of rGO played a greater role in the flexural strength of geopolymer cement than on the compressive strength and promoted the development of fracture toughness. This provided a basis for application of rGO in geopolymer cement based materials. (C) 2020 Elsevier B.V. All rights reserved.