关键词: 镍渣;矿渣;地聚合物;增韧改性

Abstract: Nickel slag,a class of industrial wastes,was used as a major solid precursor in conjunction with an alkaline activator to produce the geopolymers.The mechanical properties of geopolymers were improved through the inclusion of blast furnace slag and fiber,and the strengthening and toughening effects were investigated by characterizing the pore structure and microstructure of the binders.The results show that an increase of compressive strength and the refinement of the inner pore structure of the geopolymers are mainly due to blast furnace slag addition.In comparison with the 50 ℃ 7 d-cured nickel slag-based geopolymers,the compressive strength of geopolymers with 50％blast furnace slag content increases by 209.7％,and the total porosity and maximal distribution pores diameter reduced by 32.7％and 53.1％,respectively.The inclusion of fiber is efficient in improving the toughness of the binders.When the fiber dosage is 1.6％,the flexural strength and impact work of the 50 ℃ 7 d-cured geopolymers increase by 42.0％and 114.3％,respectively.Pull-out and tensile fracture of the fiber in the binders consumed the loading energy,resulting in an improvement of the crack resistance of geopolymers.

Key words: nickel slag;slag;geopolymer;toughening modification