水泥基体参数对水泥砂浆干缩性能的影响

采用干缩实验研究水灰比、灰砂比、水泥细度等水泥基体参数对水泥浆干缩性能的影响。结果表明,水灰比在0.35～0.60时,砂浆的干缩率随水灰比增大而增大;其它条件不变时,砂浆的干缩率随胶砂比增大而明显增大,随水泥细度提高而增大;高标号水泥的干缩率大于低标号水泥,水泥标号相同时,P.II>P.F>P.S;矿渣微粉比粉煤灰更适用于生产高性能水泥和高性能混凝土;减缩剂能明显减小水泥砂浆的干缩率。

Influence of cement parameters on the drying shrinkage of cement mortar

The influence of cement parameters (including water and cement ratio, cement and sand ratio and cement fineness etc.)on the drying shrinkage of cement mortar were studied. The results show that the drying shrinkage of cement mortars increases with increaseing of w/c ratio when w/c is ranged from 0.35 to 0.60. Given the same other conditons, drying shrinkage of cement mortar increases obviously with the increasing of c/s (cement to sand) ratio as well as with the increasing of cement finenessss.Cement shrinkage of higher strength grade cement is more than that of lower strength grade cement, Given the same strength grade, the drying shrinkage of different types of Portland cement has the following order: P. II>P. F >P. S. Compared to fly ash, ground granulated blast slag (GGBS) is a better kind of material for producing high performance cement or concrete. Shrinkage reducing agent decreases significantly the drying shrinkage of cement mortars.