The effects of five kinds of water reducing agents: calcium lignosulfonate (CLS), modified calcium lignosulfonate (GCL1-6A), amino-sulfonic based superplasticizer (ASP), sulfonated naphthalene formaldehyde (FDN) and sulfonated melamine urea formaldehyde resin (SMUF) on the mechanical performances of mortar were studied, which include the compressive strength and folding strength. The effects of water-reducing agents on the mechanical performances of mortar were evaluated by fuzzy mathematics comprehensively. The results indicated that the mechanical performances of added FDN concrete for the use of hydraulic structure and road surface or aerodrome pavement are optimum, added SMUF and GCL1-6A concrete are in the second and third place, the mechanical performances of added SMUF concrete for the use of girder, pole and so on prism components in civilian construction are optimum, which of concrete added FDN and GCL1-6A are in the second and the third place. If the factors of prices and environmental protection are considered, there are prodigious economic and environmental benefits for using GCL1-6A in concrete engineering.
