超塑化剂在不同混凝土强度等级下的减缩性能研究

Study on Shrinkage Reducing Performance of Multi-functional Comb-like Superplasticizer for the Different Strength Grades of Concrete

研究了不同混凝土强度等级下新型多功能混凝土超塑化剂SRPCA的减缩性能。无论是C30、C40或C50等级的混凝土,SRPCA在不影响混凝土强度的情况下,都能大幅度降低混凝土的干燥收缩,同掺萘系减水剂的混凝土相比,28d和60d龄期干燥收缩值降低幅度在40%～45%,基本上与掺2%减缩剂的效果接近,但SRPCA掺量不到减缩剂的10%。

The shrinkage reducing performance of multi-functional comb-like superplasticizer（SRPCA） is investigated for the different strength grades of concrete.Without reducing the concrete strength,the SRPCA can greatly decrease the drying shrinkage of concrete for C30,C40 and C50 concrete.Compared with conventional sulfonated naphthalene formaldehyde condensate superplasticizer（FDN）,the SRPCA can decrease the drying shrinkage of concrete by 40%～50% at the age of 28 days or 60 days,which is almost similar to the effort by adding 2% shrinkage reducing admixtures（SRA）.And the dosage of SRPCA is less than 10% of the combined admixture of FDN and SRA.